Mapping LCT Pegmatites: An Aeromagnetic Signature for Lithium Mineralization in Boki, South-South, Nigeria

Mapping LCT Pegmatites: An Aeromagnetic Signature for Lithium Mineralization in Boki, South-South, Nigeria | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Mapping LCT Pegmatites: An Aeromagnetic Signature for Lithium Mineralization in Boki, South-South, Nigeria Jaiyeola Gabriel Bowale, Ebilomah Prayer Adejoh, Oyudo Ifeanyi, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8113861/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: More attention has been drawn to Nigeria’s solid minerals sector in recent years, in an attempt to divert from over reliance on oil produce to grow its economy. Boki south-south which is a part of the oban massif possess the potential to host economical quantity of lithium due to its geologic and structural settings. Methods: Geophysical survey was employed to map the suspected lithium-rich pegmatic veins in the study area. Aeromagnetic survey was utilised for the survey. the survey was carried out using flight lines spaced at 500 meters, with tie lines at 2- kilometer intervals. An average terrain clearance of 80 meters was maintained to ensure highresolution detection of subsurface features. The flight lines were oriented northwest–southeast (NW–SE), while tie lines followed a northeast–southwest (NE–SW) orientation. Results: A geologically favorable environment for lithium exploration were delineated with high magnetic anomalies, elevated potassium concentrations and presence of numerous intersecting lineaments which all together indicate a structurally complex and potentially mineralized terrain. Conclusions: The northeastern and central parts of the study area exhibits signatures consistent with felsic lithologies, potassic alteration, and possible hydrothermal activity. Geophysical survery Aeromagnetic signature Lithium LCT Pegmatites Anomaly Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1. Introduction Nigeria holds vast reserves of valuable mineral resources, and regions like Boki Local Government Area in Cross River State are gaining attention for their mineral potential, especially due to the dominance of hornblende granite and extensive stream channel systems [ 1 ][ 2 ]. Among the many critical minerals, tantalite, mica, beryl, and lithium are becoming increasingly important due to their applications in clean energy, modern electronics, aerospace, and industrial technologies [ 3 ][ 4 ]. These minerals are often linked to rare-metal-bearing pegmatites, which are typically hosted within granitic terrains such as those found in Boki [ 5 ][ 6 ]. The growing demand for these strategic minerals, especially lithium, a key component in rechargeable batteries for electric vehicles, mobile phones, and energy storage systems, highlights the importance of regions like Boki, where favorable geology aligns with global resource needs[ 7 ]. Similarly, associated minerals like beryl and columbite-tantalite (coltan) play essential roles in manufacturing components for the tech and aerospace industries [ 8 ][ 9 ]. In Boki, the hornblende-rich granites, alongside weathering and erosion processes, have likely contributed to the accumulation of heavy minerals within nearby stream beds, creating conditions favorable for the formation of placer deposits [ 10 ][ 11 ]. These alluvial settings are ideal for concentrating minerals like gold, cassiterite, and tantalite, which are resistant to chemical breakdown and tend to settle in slow-moving water channels [ 12 ]. To evaluate the mineral prospect of the area, an initial desktop geological assessment was conducted, using a combination of available high-resolution airborne geophysical data, including aeromagnetic and radiometric surveys as well as satellite imagery and regional geological maps [ 13 ][ 14 ]. This analysis aimed to pinpoint areas of interest by identifying lithological boundaries, fault systems, and geophysical anomalies commonly associated with mineralized pegmatites [ 15 ][ 16 ]. This integrated desktop approach provides a cost-effective framework for early-stage mineral exploration, guiding future field mapping, stream sediment sampling, trenching, and geochemical verification [ 17 ]. With its distinctive geology and favorable geomorphology, Boki LGA represents a promising area for future investment in critical mineral development, aligned with both national economic priorities and global clean energy trends [ 18 ]. 2. Location and Accesibility This study focuses on Boki Local Government Area (LGA), located in the southeastern part of Cross River State, Nigeria [ 1 ][ 3 ]. The area lies approximately between latitudes 6°10′N to 6°25′N and longitudes 8°55′E to 9°20′E (Fig. 1 ), with an eastern boundary adjoining Cameroon [ 19 ]. It shares borders with Obanliku and Bekwarra LGAs to the north, Ikom to the west, and Etung to the south [ 10 ]. Initial access during this study was facilitated through existing community trails and farm paths, which allowed for on-site verification of satellite and geophysical data [ 14 ]. Handheld GPS devices were used to capture key coordinates and verify terrain features, enabling accurate spatial mapping for subsequent field investigations [ 5 ]. Boki LGA offers a geologically favorable environment for rare-metal exploration, with an adequate level of access that supports early-stage geological mapping, stream sediment sampling, and geochemical fieldwork [ 6 ]. 3. Geologic Settings 3.1 Regional Geology Boki Local Government Area, located in southeastern Cross River State, is geologically positioned within the Oban Massif, a southeastern extension of the Nigerian Basement Complex [ 20 ][ 21 ]. This massif is part of the Pan-African Mobile Belt, which extends eastward into the Cameroon Highlands [ 22 ][ 23 ]. The rocks in this region are of Precambrian origin and were extensively affected by the Pan-African orogeny (~ 600 Ma), a major tectono-metamorphic event that reworked earlier crustal blocks across West Africa [ 24 ][ 25 ]. The regional geology of Boki is thus shaped by ancient crustal evolution, involving multiple episodes of deformation, high-grade metamorphism, and intrusive magmatism [ 5 ]. The dominant rock types within the study area terrain include hornblende-biotite granite(Fig. 2 ), granite gneiss, migmatites, and minor quartz-mica schists [ 20 ][ 21 ]. These are characteristic of the Nigerian Basement Complex and often occur as large crystalline bodies. The hornblende-rich granites are typically coarse-grained, with evidence of post-tectonic emplacement [ 26 ][ 30 ]. These granitoids are important not only as major lithologies but also as potential hosts for rare-metal pegmatites, which intrude them in structurally weak zones [ 6 ][ 15 ]. In addition, minor occurrences of amphibolites and metavolcanic enclaves have been reported in the surrounding terrain, suggesting localized greenstone remnants within the basement [ 21 ][ 31 ]. 3.2 Local Geology The study area covers portions that have basement rocks and have undergone extensive ductile and brittle deformation, resulting in the development of major shear zones, fractures, and fault systems that control the structural grain of the area [ 20 ][ 26 ]. These structural features are significant because they not only influence the emplacement of younger intrusives like granites and pegmatites, but also serve as fluid pathways for hydrothermal mineralizing systems [ 5 ][ 25 ]. Notably, the presence of pegmatitic intrusions and potassic granites within the Boki terrain is indicative of a late- to post-tectonic magmatic phase, often associated with rare metal enrichment (e.g., tantalum, niobium, lithium, and rare earth elements) [ 6 ][ 15 ]. These rocks typically occur along structural corridors such as faults, shear zones, and contact zones, which are commonly targeted in mineral exploration due to their metallogenic potential [ 14 ][ 17 ]. In addition, the area exhibits signs of hydrothermal alteration, especially along zones of structural weakness, which may be conducive to the formation of gold-bearing quartz veins and associated polymetallic mineralization [ 8 ][ 10 ]. The geological history of repeated deformation and intrusive activity makes the Boki region highly prospective, particularly for structurally controlled mineral deposits [ 22 ][ 24 ]. 4. Methodology For this study, data acquisition focused on evaluating the rare-metal mineral potential of Boki Local Government Area in Cross River State, using a combination of high-resolution airborne magnetic data, geological maps, and digital elevation models (DEM) [ 5 ][ 14 ]. These datasets were selected to help identify and interpret geological structures and lithological features associated with pegmatite-hosted mineralization within the hornblende granite terrain that characterizes the study area [ 6 ][ 31 ]. The primary geophysical dataset utilized was aeromagnetic data obtained from the Nigerian Geological Survey Agency (NGSA) as part of its nationwide airborne survey program [ 32 ][ 33 ]. In this region, the survey was carried out using flight lines spaced at 500 meters, with tie lines at 2-kilometer intervals. An average terrain clearance of 80 meters was maintained to ensure high-resolution detection of subsurface features [ 32 ]. The flight lines were oriented northwest–southeast (NW–SE), while tie lines followed a northeast–southwest (NE–SW) orientation. This layout provided optimum coverage for resolving linear features such as fractures, faults, and pegmatite-hosting shear zones [ 14 ]. In addition to the aeromagnetic data, geological maps at scales of 1:250,000 were reviewed to understand the regional lithological distribution, especially areas dominated by hornblende granite, gneiss, and pegmatite intrusions. Remote sensing imagery from Landsat 8 and Google Earth Pro was used to trace surface lineaments and identify terrain variations [ 31 ]. Previous studies and artisanal mining records from nearby localities were consulted to highlight known zones of mineral occurrence, particularly for muscovite, beryl, and columbite-tantalite [ 10 ][ 15 ]. Together, these datasets formed the foundation for a multi-layered geoscientific interpretation[ 6 ][ 14 ]. 5. Results Total Magnetic Intensity : Color Scale of the TMI ranges from deep blues (low magnetic intensity) to greens, yellows, oranges, and reds/purples (high magnetic intensity). The legend on the right shows values ranging from − 31 (blue) to 59 (magenta/purple) (Fig. 3 ). Blues and Greens (Low Intensity): These areas generally correspond to rocks with lower magnetic susceptibility, such as sedimentary rocks, felsic igneous rocks, or areas of thicker overburden. In the TMI map, there are significant blue and green zones, particularly in the southwestern and parts of the northern and eastern sections of the overall mapped area. Yellows, Oranges, and Reds/Purples (High Intensity): These colors indicate rocks with higher magnetic susceptibility, often associated with mafic to ultramafic igneous rocks, some metamorphic rocks, or iron-rich formations. The map shows several distinct anomalies. Elongated Red/Purple Anomalies: There are prominent linear or curvilinear high-intensity anomalies, particularly trending roughly NW-SE to E-W across the map. These often represent magnetic lineaments, which could be dikes, sills, faults, or contacts between different rock units. Some localized, irregular high-intensity features could indicate discrete magnetic bodies, such as intrusive plugs or isolated ore bodies. Within the study area there's a mix of green, yellow, and some orange/red features. This suggests the presence of varying magnetic susceptibilities within this specific target zone, implying diverse lithologies or structural features. The western part of the outlined area appears to have generally lower magnetic intensity (greener), while the eastern part shows some higher intensity features (yellows and oranges). First Vertical Derivative (1VD) The 1VD map (Fig. 3 ) enhances the edges of magnetic anomalies and helps detect the top edges of buried magnetic bodies [ 34 ]. The First Vertical Derivative (FVD) map is a special type of magnetic map used in mineral exploration to enhance shallow geological features [ 34 ]. It works by mathematically highlighting areas where there is a sharp change in magnetic intensity, which often occurs at the edges of rock units or faults [ 34 ]. Within the licence area, the red and purple zones outline zones of sharp magnetic contrasts, commonly linked to lithologic contacts or shear zones [ 10 ]. Also, a significant linear trend from the southwest to northeast is clearly visible, suggesting a major structural alignment, possibly an avenue for pegmatite intrusion or fault-controlled mineralization [ 5 ][ 17 ]. The Analytical Signal The Analytical Signal Map (Fig. 5 ) is very useful for pinpointing the exact locations of magnetic sources within the study area [ 35 ]. The brightest spots (in red and purple) mark where magnetic rocks are most concentrated. Unlike the Total Magnetic Intensity (TMI) map, this map gives a much clearer view of individual magnetic bodies. This map is particularly strong for directly locating magnetic sources within the study area, as the maxima (bright red/purple) are situated over the magnetic bodies [ 36 ]. Bright colors (pink, red) indicate areas where magnetic rocks are closer to the surface or strongly magnetic. In the central and southwestern parts of the block, there are well-defined high-amplitude anomalies; these are likely to be magnetic rock bodies such as mafic intrusions or magnetite-bearing pegmatites, while blue zones are low-magnetic areas, possibly sedimentary or deeply weathered zones [ 10 ][ 5 ]. The Tilt Derivative The tilt derivative map (Fig. 6 ) enhances the edges of magnetic sources and highlights geological contacts. The alternating color bands (red, green, blue) reveal linear features and structural alignments. These are interpreted as fault zones or fracture systems, which are significant for controlling the emplacement of pegmatites. The central and northeastern portions of the map show high contrast zones, suggesting prospective areas for detailed follow-up work. Source parameter Imaging This map (Fig. 7 ) is critical for understanding the 3D geometry of the magnetic sources within the study area. The color scale ranges from deep blue (91 meters) representing shallow depths to green, yellow, orange, red, and magenta/purple (661 meters) representing deeper depths. This map directly estimates the depth to the top of magnetic sources, shallow sources which are Blues/Greens Prevalent in the northern and central-eastern parts of the overall map, indicating magnetic sources closer to the surface. Deeper Sources (Reds/Purples) dominate the southern and some scattered central parts, suggesting that magnetic basement or strong magnetic units are deeper in these areas. The SPI map effectively illustrates the "topography" of the magnetic basement or major magnetic horizons. Areas of deeper sources (reds/purples) could represent sedimentary basins or troughs, while shallow sources (blues/greens) could indicate basement highs or uplifted blocks. The study area shows a mixture of depths. The larger western block appears to have relatively shallow to moderate depths (greens and yellows). The eastern, smaller blocks show a range of depths, with some shallow "hot spots" (blues) and deeper sections (oranges/reds). This variability in depth within the target area is crucial for understanding the geological setting and potential exploration targets. Radiometric Ternary Image This map is a ternary (three-component) radiometric image, combining measurements of Potassium (K), Thorium (Th), and Uranium (U) (Fig. 8 ). The radiometric map shows the natural gamma radiation levels emitted from the surface rocks. This form of geophysical survey measures the concentration of three key radioactive elements,potassium (K), thorium (Th), and uranium (U). These elements provide valuable geochemical clues about the lithology, alteration zones, and potential mineralization within the mapped region. The color scheme employed in the map follows a ternary color blending system where red indicates potassium, blue represents thorium, and green signifies uranium. Areas with mixed colors such as magenta, purple, or cyan suggest combinations of these elements in varying proportions. Within the Boki study area, the central and northeastern sections display a dominance of magenta and pink coloration. This indicates a high potassium signature, often associated with felsic rocks like granites and pegmatites that contain K-feldspar and muscovite. The presence of these rocks is significant because they are common hosts of rare-metal pegmatites, particularly those enriched in lithium, tantalum, and niobium. Consequently, these potassium-rich zones represent high-priority targets for follow-up exploration. Toward the southern and western margins of the map, a shift in color toward darker blue a violet tones is evident. These suggest an increase in thorium concentration, which is typically found in accessory minerals such as monazite and zircon. Thorium is geochemically immobile and often reflects the primary mineral composition of mature granitic terrains. The implication of these blue zones is that they may mark the presence of evolved, resistant source rocks that could also contribute to rare-element concentrations in nearby pegmatitic intrusions. In some area, especially in the eastern part of the map, greenish tints become more apparent. These signify uranium-enriched areas. Unlike thorium, uranium is mobile under oxidizing conditions and may migrate along fractures or faults. Therefore, these green zones may point to hydrothermal alteration zones, fault-controlled mineralization, or even radioactive pegmatites. While further investigation is required to verify these zones, they remain of interest due to the potential for structurally hosted rare-metal mineralization. Structural Interpretation Linear features were interpreted from the geophysical data, with the study area outlined. The lineament map (Fig. 8 ) of the study area reveals several linear features interpreted as faults or fractures, with dominant NW–SE and NE–SW trends. Within the defined study block, a moderate density of lineaments is observed, with notable intersections in the central and southeastern parts.These intersecting structures suggest zones of increased permeability and structural preparation, which are favorable for mineralization and fluid migration. The alignment of some lineaments with regional trends further indicates potential deep-seated structural influence.Based on this interpretation, the study area holds significant exploration potential. Key recommendations include ground-truthing, geophysical surveys, and geochemical sampling focused on zones of lineament intersection to refine targets for mineral exploration. 5.1 Result Discussion This report presents the integrated interpretation of aeromagnetic datasets and structural features across the Boki region in Cross River State, Nigeria. The processed data include the Total Magnetic Intensity (TMI), First Vertical Derivative (1VD), Second Vertical Derivative (2VD), Tilt Derivative, and Lineament Map. These datasets collectively provide insight into the magnetic properties of subsurface rocks, their structural arrangement, and potential zones for mineral exploration within the defined study area. The Total Magnetic Intensity (TMI) map displays variations in magnetic intensity across the area, with the highest anomalies occurring predominantly within and around the study block. These high magnetic values are interpreted as responses from magnetite-rich rock units or intrusive bodies, while the low magnetic zones likely correspond to sedimentary cover or structurally demagnetized zones such as faults. The magnetic anomaly trends observed, particularly the northwest–southeast and northeast–southwest alignments, reflect regional tectonic influences and underline the structural complexity of the basement. Further refinement of the magnetic signatures is evident in the First Vertical Derivative (1VD) map, which highlights the shallow and near-surface features by sharpening magnetic boundaries. Within the study area, the 1VD map reveals strong linear anomalies and pronounced gradients, interpreted as lithological contacts, fault boundaries, and zones of fracturing. These features correspond with major geologic discontinuities and provide preliminary indicators of structurally controlled mineralization. The Second Vertical Derivative (2VD) map enhances even finer structural details, offering an intensified view of abrupt magnetic contrasts. The 2VD anomalies occur as narrow, high frequency signatures that likely represent minor fault systems, narrow dykes, or small-scale fractures. These features are especially useful in identifying shallow sources with high exploration potential, particularly where they align or intersect with larger structures observed in the TMI and 1VD maps. The Tilt Derivative map simplifies the interpretation of magnetic contacts by stabilizing amplitude variations across broad anomalies. It delineates well-defined boundaries and enhances both subtle and sharp transitions. The tilt map reveals a network of structurally significant lineaments, many of which pass through or terminate within the study area. These are interpreted as magnetic contacts, faults, or shear zones, and their continuity across the survey area suggests deep-rooted structural control. Complementing the geophysical interpretations is the Lineament Map, which captures structural elements directly from filtered magnetic data. It depicts a dense network of linear features trending predominantly in NW–SE and NE–SW directions. The study area hosts several of these lineaments, with some showing clear intersections and clusters. Such areas of structural convergence are geologically significant, as they may serve as conduits for hydrothermal fluids or host zones of mineralization. The central and southern parts of the study block are especially promising, where lineament intersections coincide with magnetic highs and abrupt gradients identified in the derivative maps. Given the results of this interpretation, it is recommended that exploration activities prioritize areas within the study block where high magnetic anomalies align with derivative gradients and lineament intersections. Field validation, supported by ground geophysical surveys such as Induced Polarization (IP) or resistivity, will be crucial for delineating specific targets. Additionally, geochemical sampling should be carried out in structurally complex zones to confirm mineral presence at the surface or near-surface. In conclusion, the Boki area presents significant exploration potential based on the aeromagnetic and structural interpretations. The convergence of key geophysical anomalies, fault-controlled structures, and defined lineament patterns within the study area supports the presence of subsurface mineralization. Follow-up studies are highly recommended to assess the economic viability of these targets. 6. Conclusion The integrated interpretation of aeromagnetic, radiometric, and structural data over the Boki area has revealed a geologically favorable environment for mineral exploration. High magnetic anomalies, elevated potassium concentrations, and the presence of numerous intersecting lineaments collectively indicate a structurally complex and potentially mineralized terrain. Within the study area, specific zones,particularly in the northeastern and central parts exhibit signatures consistent with felsic lithologies, potassic alteration, and possible hydrothermal activity. While these remote sensing and geophysical results are promising, they do not independently confirm the presence of economic mineral deposits. Therefore, systematic ground validation is essential. Through geological mapping, geochemical sampling, and targeted geophysical surveys, the current interpretations can be refined and upgraded into concrete exploration targets. With proper follow-up, the area holds significant potential for the discovery of valuable mineral resources such as gold, rare earth elements, and associated pegmatite-hosted minerals. 7. Recommendation The radiometric and structural analysis within the study block indicates a highly prospective geological setting for mineral exploration. Notably, elevated potassium levels detected in the northeastern portion of the area suggest the presence of felsic rocks like granites, or zones of potassic alteration, both of which are commonly associated with hydrothermal activity and potential mineralization. Additionally, the widespread network of intersecting lineaments across the terrain increases its exploration potential, as such structural features often act as pathways for mineralizing fluids. Nevertheless, while these radiometric signatures are encouraging, they do not serve as conclusive proof of mineral occurrences such as gold or rare earth elements. Therefore, these preliminary findings must be validated and expanded upon through detailed ground-based surveys. Initiate geochemical sampling immediately upon identifying positive field indicators such as Pegmatitic intrusions, alteration zones,Structurally controlled outcrops. Declarations Acknowledgement: Special thanks to the management of Dexter Roy Geoconsult Limited for granting the permission to use the dataset and providing the workstation to interpret the data. Funding: No funding was received to assist with the preparation of this manuscript. Conflicts of Interest: The authors have no conflicts of interest to declare that are relevant to the content of this article. Ethics Statement: Not applicable. Consent to Publish Declaration: All authors has read and agreed to the publication of the original manuscript. Consent to Participate Declaration: Not applicable Author Contribution J.G. and E.P. conceptualize the project, E.P. O.E device the methodology. O.E., O.I. acquire the dataset and analyses, O.E wrote the main manuscript text. O.I., A.M. and L.A. prepared all the figures and maps. 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Geophysics, 37(3), 507–517. https://doi.org/10.1190/1.1440276 Roest, W. R., Verhoef, J., & Pilkington, M. (1992). Magnetic interpretation using the 3-D analytic signal. Geophysics, 57(1), 116–125. https://doi.org/10.1190/1.1443174 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8113861","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":559060236,"identity":"9f8662bf-c359-46cb-9ad0-3e83a709c31b","order_by":0,"name":"Jaiyeola Gabriel Bowale","email":"","orcid":"","institution":"Dexter Roy Geoconsult Limited","correspondingAuthor":false,"prefix":"","firstName":"Jaiyeola","middleName":"Gabriel","lastName":"Bowale","suffix":""},{"id":559060240,"identity":"fc003e5f-373f-436c-8720-d24b9cab5eae","order_by":1,"name":"Ebilomah Prayer Adejoh","email":"","orcid":"","institution":"Dexter Roy Geoconsult 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1","display":"","copyAsset":false,"role":"figure","size":357588,"visible":true,"origin":"","legend":"\u003cp\u003eMap showing Boki local government area.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/6d80fc4780cde92836e66453.png"},{"id":98065117,"identity":"39110d7a-bb2d-419a-a637-0079cd9dc74d","added_by":"auto","created_at":"2025-12-12 11:40:07","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":400646,"visible":true,"origin":"","legend":"\u003cp\u003eGeologic map of the study area(Adapted from NGSA, 2011)\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/5000a391aa89ba76500975f6.png"},{"id":98065113,"identity":"ae95d263-f900-4d78-bdd1-06542cdc3780","added_by":"auto","created_at":"2025-12-12 11:40:07","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1282722,"visible":true,"origin":"","legend":"\u003cp\u003eTotal Magnetic Field Intensity\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/bf2bafce5949302adf74b4b6.png"},{"id":98428485,"identity":"eb66abf4-f988-430d-a7f4-75da6724893a","added_by":"auto","created_at":"2025-12-17 16:42:03","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1660060,"visible":true,"origin":"","legend":"\u003cp\u003eFirst Vertical Derivative Map\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/09f49768bac6dcd094b3229b.png"},{"id":98065119,"identity":"07fbc6bf-a1e9-4ba0-93af-83ec5d27503e","added_by":"auto","created_at":"2025-12-12 11:40:07","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":1785507,"visible":true,"origin":"","legend":"\u003cp\u003eAnalytic Signal Map\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/1771eb9e3f80dde7cbc591b9.png"},{"id":98428822,"identity":"24ad0c43-534b-4f6b-a877-e0b384425fe8","added_by":"auto","created_at":"2025-12-17 16:42:26","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":1466089,"visible":true,"origin":"","legend":"\u003cp\u003eTilt Derivative Map\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/0bd138cfb1f39063054002dc.png"},{"id":98426597,"identity":"b44c702f-38c7-493c-bedf-3194efe0f7d8","added_by":"auto","created_at":"2025-12-17 16:37:31","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":1497239,"visible":true,"origin":"","legend":"\u003cp\u003eSource Parameter Imaging\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/1e7458da6b4670e047b44923.png"},{"id":98065125,"identity":"04d8142f-590a-4e3f-85ed-6890b4f7ddb1","added_by":"auto","created_at":"2025-12-12 11:40:07","extension":"jpeg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":1211671,"visible":true,"origin":"","legend":"\u003cp\u003eRadiometric Ternary image\u003c/p\u003e","description":"","filename":"floatimage8.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/0be5e3cfd9774256ddb10b77.jpeg"},{"id":98428606,"identity":"3d1e0602-3c7b-4550-b867-c082d647c034","added_by":"auto","created_at":"2025-12-17 16:42:11","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":237342,"visible":true,"origin":"","legend":"\u003cp\u003eLineaments showing structural trend\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/c4e83086b83b036e4a78413a.png"},{"id":105896171,"identity":"080d477b-e992-49cd-adda-ed00bbb08f01","added_by":"auto","created_at":"2026-04-01 08:44:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":11533451,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8113861/v1/60f8df2d-af45-4d4a-9025-e64976933240.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Mapping LCT Pegmatites: An Aeromagnetic Signature for Lithium Mineralization in Boki, South-South, Nigeria","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eNigeria holds vast reserves of valuable mineral resources, and regions like Boki Local Government Area in Cross River State are gaining attention for their mineral potential, especially due to the dominance of hornblende granite and extensive stream channel systems [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e][\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Among the many critical minerals, tantalite, mica, beryl, and lithium are becoming increasingly important due to their applications in clean energy, modern electronics, aerospace, and industrial technologies [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e][\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. These minerals are often linked to rare-metal-bearing pegmatites, which are typically hosted within granitic terrains such as those found in Boki [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e][\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. The growing demand for these strategic minerals, especially lithium, a key component in rechargeable batteries for electric vehicles, mobile phones, and energy storage systems, highlights the importance of regions like Boki, where favorable geology aligns with global resource needs[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Similarly, associated minerals like beryl and columbite-tantalite (coltan) play essential roles in manufacturing components for the tech and aerospace industries [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e][\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In Boki, the hornblende-rich granites, alongside weathering and erosion processes, have likely contributed to the accumulation of heavy minerals within nearby stream beds, creating conditions favorable for the formation of placer deposits [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e][\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. These alluvial settings are ideal for concentrating minerals like gold, cassiterite, and tantalite, which are resistant to chemical breakdown and tend to settle in slow-moving water channels [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. To evaluate the mineral prospect of the area, an initial desktop geological assessment was conducted, using a combination of available high-resolution airborne geophysical data, including aeromagnetic and radiometric surveys as well as satellite imagery and regional geological maps [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e][\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. This analysis aimed to pinpoint areas of interest by identifying lithological boundaries, fault systems, and geophysical anomalies commonly associated with mineralized pegmatites [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e][\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. This integrated desktop approach provides a cost-effective framework for early-stage mineral exploration, guiding future field mapping, stream sediment sampling, trenching, and geochemical verification [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. With its distinctive geology and favorable geomorphology, Boki LGA represents a promising area for future investment in critical mineral development, aligned with both national economic priorities and global clean energy trends [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e"},{"header":"2. Location and Accesibility","content":"\u003cp\u003eThis study focuses on Boki Local Government Area (LGA), located in the southeastern part of Cross River State, Nigeria [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e][\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The area lies approximately between latitudes 6\u0026deg;10\u0026prime;N to 6\u0026deg;25\u0026prime;N and longitudes 8\u0026deg;55\u0026prime;E to 9\u0026deg;20\u0026prime;E (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), with an eastern boundary adjoining Cameroon [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. It shares borders with Obanliku and Bekwarra LGAs to the north, Ikom to the west, and Etung to the south [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Initial access during this study was facilitated through existing community trails and farm paths, which allowed for on-site verification of satellite and geophysical data [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Handheld GPS devices were used to capture key coordinates and verify terrain features, enabling accurate spatial mapping for subsequent field investigations [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Boki LGA offers a geologically favorable environment for rare-metal exploration, with an adequate level of access that supports early-stage geological mapping, stream sediment sampling, and geochemical fieldwork [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"3. Geologic Settings","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e3.1 Regional Geology\u003c/h2\u003e\u003cp\u003eBoki Local Government Area, located in southeastern Cross River State, is geologically positioned within the Oban Massif, a southeastern extension of the Nigerian Basement Complex [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e][\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. This massif is part of the Pan-African Mobile Belt, which extends eastward into the Cameroon Highlands [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e][\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. The rocks in this region are of Precambrian origin and were extensively affected by the Pan-African orogeny (~\u0026thinsp;600 Ma), a major tectono-metamorphic event that reworked earlier crustal blocks across West Africa [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e][\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The regional geology of Boki is thus shaped by ancient crustal evolution, involving multiple episodes of deformation, high-grade metamorphism, and intrusive magmatism [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The dominant rock types within the study area terrain include hornblende-biotite granite(Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), granite gneiss, migmatites, and minor quartz-mica schists [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e][\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. These are characteristic of the Nigerian Basement Complex and often occur as large crystalline bodies. The hornblende-rich granites are typically coarse-grained, with evidence of post-tectonic emplacement [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e][\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. These granitoids are important not only as major lithologies but also as potential hosts for rare-metal pegmatites, which intrude them in structurally weak zones [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e][\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. In addition, minor occurrences of amphibolites and metavolcanic enclaves have been reported in the surrounding terrain, suggesting localized greenstone remnants within the basement [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e][\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e3.2 Local Geology\u003c/h2\u003e\u003cp\u003eThe study area covers portions that have basement rocks and have undergone extensive ductile and brittle deformation, resulting in the development of major shear zones, fractures, and fault systems that control the structural grain of the area [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e][\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. These structural features are significant because they not only influence the emplacement of younger intrusives like granites and pegmatites, but also serve as fluid pathways for hydrothermal mineralizing systems [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e][\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Notably, the presence of pegmatitic intrusions and potassic granites within the Boki terrain is indicative of a late- to post-tectonic magmatic phase, often associated with rare metal enrichment (e.g., tantalum, niobium, lithium, and rare earth elements) [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e][\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. These rocks typically occur along structural corridors such as faults, shear zones, and contact zones, which are commonly targeted in mineral exploration due to their metallogenic potential [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e][\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In addition, the area exhibits signs of hydrothermal alteration, especially along zones of structural weakness, which may be conducive to the formation of gold-bearing quartz veins and associated polymetallic mineralization [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e][\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The geological history of repeated deformation and intrusive activity makes the Boki region highly prospective, particularly for structurally controlled mineral deposits [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e][\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Methodology","content":"\u003cp\u003eFor this study, data acquisition focused on evaluating the rare-metal mineral potential of Boki Local Government Area in Cross River State, using a combination of high-resolution airborne magnetic data, geological maps, and digital elevation models (DEM) [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e][\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. These datasets were selected to help identify and interpret geological structures and lithological features associated with pegmatite-hosted mineralization within the hornblende granite terrain that characterizes the study area [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e][\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. The primary geophysical dataset utilized was aeromagnetic data obtained from the Nigerian Geological Survey Agency (NGSA) as part of its nationwide airborne survey program [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e32\u003c/span\u003e][\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. In this region, the survey was carried out using flight lines spaced at 500 meters, with tie lines at 2-kilometer intervals. An average terrain clearance of 80 meters was maintained to ensure high-resolution detection of subsurface features [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. The flight lines were oriented northwest\u0026ndash;southeast (NW\u0026ndash;SE), while tie lines followed a northeast\u0026ndash;southwest (NE\u0026ndash;SW) orientation. This layout provided optimum coverage for resolving linear features such as fractures, faults, and pegmatite-hosting shear zones [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn addition to the aeromagnetic data, geological maps at scales of 1:250,000 were reviewed to understand the regional lithological distribution, especially areas dominated by hornblende granite, gneiss, and pegmatite intrusions. Remote sensing imagery from Landsat 8 and Google Earth Pro was used to trace surface lineaments and identify terrain variations [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e\u003cp\u003ePrevious studies and artisanal mining records from nearby localities were consulted to highlight known zones of mineral occurrence, particularly for muscovite, beryl, and columbite-tantalite [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e][\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Together, these datasets formed the foundation for a multi-layered geoscientific interpretation[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e][\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e"},{"header":"5. Results","content":"\u003cp\u003e\u003cb\u003eTotal Magnetic Intensity\u003c/b\u003e: Color Scale of the TMI ranges from deep blues (low magnetic intensity) to greens, yellows, oranges, and reds/purples (high magnetic intensity). The legend on the right shows values ranging from \u0026minus;\u0026thinsp;31 (blue) to 59 (magenta/purple) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Blues and Greens (Low Intensity): These areas generally correspond to rocks with lower magnetic susceptibility, such as sedimentary rocks, felsic igneous rocks, or areas of thicker overburden. In the TMI map, there are significant blue and green zones, particularly in the southwestern and parts of the northern and eastern sections of the overall mapped area. Yellows, Oranges, and Reds/Purples (High Intensity): These colors indicate rocks with higher magnetic susceptibility, often associated with mafic to ultramafic igneous rocks, some metamorphic rocks, or iron-rich formations. The map shows several distinct anomalies. Elongated Red/Purple Anomalies: There are prominent linear or curvilinear high-intensity anomalies, particularly trending roughly NW-SE to E-W across the map. These often represent magnetic lineaments, which could be dikes, sills, faults, or contacts between different rock units. Some localized, irregular high-intensity features could indicate discrete magnetic bodies, such as intrusive plugs or isolated ore bodies. Within the study area there's a mix of green, yellow, and some orange/red features. This suggests the presence of varying magnetic susceptibilities within this specific target zone, implying diverse lithologies or structural features. The western part of the outlined area appears to have generally lower magnetic intensity (greener), while the eastern part shows some higher intensity features (yellows and oranges).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eFirst Vertical Derivative (1VD)\u003c/strong\u003e\u003cp\u003eThe 1VD map (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) enhances the edges of magnetic anomalies and helps detect the top edges of buried magnetic bodies [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. The First Vertical Derivative (FVD) map is a special type of magnetic map used in mineral exploration to enhance shallow geological features [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. It works by mathematically highlighting areas where there is a sharp change in magnetic intensity, which often occurs at the edges of rock units or faults [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. Within the licence area, the red and purple zones outline zones of sharp magnetic contrasts, commonly linked to lithologic contacts or shear zones [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Also, a significant linear trend from the southwest to northeast is clearly visible, suggesting a major structural alignment, possibly an avenue for pegmatite intrusion or fault-controlled mineralization [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e][\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eThe Analytical Signal\u003c/strong\u003e\u003cp\u003eThe Analytical Signal Map (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e) is very useful for pinpointing the exact locations of magnetic sources within the study area [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. The brightest spots (in red and purple) mark where magnetic rocks are most concentrated. Unlike the Total Magnetic Intensity (TMI) map, this map gives a much clearer view of individual magnetic bodies. This map is particularly strong for directly locating magnetic sources within the study area, as the maxima (bright red/purple) are situated over the magnetic bodies [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. Bright colors (pink, red) indicate areas where magnetic rocks are closer to the surface or strongly magnetic. In the central and southwestern parts of the block, there are well-defined high-amplitude anomalies; these are likely to be magnetic rock bodies such as mafic intrusions or magnetite-bearing pegmatites, while blue zones are low-magnetic areas, possibly sedimentary or deeply weathered zones [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e][\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eThe Tilt Derivative\u003c/strong\u003e\u003cp\u003eThe tilt derivative map (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e) enhances the edges of magnetic sources and highlights geological contacts. The alternating color bands (red, green, blue) reveal linear features and structural alignments. These are interpreted as fault zones or fracture systems, which are significant for controlling the emplacement of pegmatites. The central and northeastern portions of the map show high contrast zones, suggesting prospective areas for detailed follow-up work.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eSource parameter Imaging\u003c/strong\u003e\u003cp\u003eThis map (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e) is critical for understanding the 3D geometry of the magnetic sources within the study area. The color scale ranges from deep blue (91 meters) representing shallow depths to green, yellow, orange, red, and magenta/purple (661 meters) representing deeper depths. This map directly estimates the depth to the top of magnetic sources, shallow sources which are Blues/Greens Prevalent in the northern and central-eastern parts of the overall map, indicating magnetic sources closer to the surface. Deeper Sources (Reds/Purples) dominate the southern and some scattered central parts, suggesting that magnetic basement or strong magnetic units are deeper in these areas. The SPI map effectively illustrates the \"topography\" of the magnetic basement or major magnetic horizons. Areas of deeper sources (reds/purples) could represent sedimentary basins or troughs, while shallow sources (blues/greens) could indicate basement highs or uplifted blocks. The study area shows a mixture of depths. The larger western block appears to have relatively shallow to moderate depths (greens and yellows). The eastern, smaller blocks show a range of depths, with some shallow \"hot spots\" (blues) and deeper sections (oranges/reds). This variability in depth within the target area is crucial for understanding the geological setting and potential exploration targets.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eRadiometric Ternary Image\u003c/strong\u003e\u003cp\u003eThis map is a ternary (three-component) radiometric image, combining measurements of Potassium (K), Thorium (Th), and Uranium (U) (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e). The radiometric map shows the natural gamma radiation levels emitted from the surface rocks. This form of geophysical survey measures the concentration of three key radioactive elements,potassium (K), thorium (Th), and uranium (U). These elements provide valuable geochemical clues about the lithology, alteration zones, and potential mineralization within the mapped region. The color scheme employed in the map follows a ternary color blending system where red indicates potassium, blue represents thorium, and green signifies uranium. Areas\u003c/p\u003e\u003c/p\u003e\u003cp\u003ewith mixed colors such as magenta, purple, or cyan suggest combinations of these elements in varying proportions. Within the Boki study area, the central and northeastern sections display a dominance of magenta and pink coloration. This indicates a high potassium signature, often associated with felsic rocks like granites and pegmatites that contain K-feldspar and muscovite. The presence of these rocks is significant because they are common hosts of rare-metal pegmatites, particularly those enriched in lithium, tantalum, and niobium. Consequently, these potassium-rich zones represent high-priority targets for follow-up exploration. Toward the southern and western margins of the map, a shift in color toward darker blue a violet tones is evident. These suggest an increase in thorium concentration, which is typically found in accessory minerals such as monazite and zircon. Thorium is geochemically immobile and often reflects the primary mineral composition of mature granitic terrains. The implication of these blue zones is that they may mark the presence of evolved, resistant source rocks that could also contribute to rare-element concentrations in nearby pegmatitic intrusions. In some area, especially in the eastern part of the map, greenish tints become more apparent. These signify uranium-enriched areas. Unlike thorium, uranium is mobile under oxidizing conditions and may migrate along fractures or faults. Therefore, these green zones may point to hydrothermal alteration zones, fault-controlled mineralization, or even radioactive pegmatites. While further investigation is required to verify these zones, they remain of interest due to the potential for structurally hosted rare-metal mineralization.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eStructural Interpretation\u003c/b\u003e\u003c/p\u003e\u003cp\u003eLinear features were interpreted from the geophysical data, with the study area outlined. The lineament map (Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e) of the study area reveals several linear features interpreted as faults or fractures, with dominant NW\u0026ndash;SE and NE\u0026ndash;SW trends. Within the defined study block, a moderate density of lineaments is observed, with notable intersections in the central and southeastern parts.These intersecting structures suggest zones of increased permeability and structural preparation, which are favorable for mineralization and fluid migration. The alignment of some lineaments with regional trends further indicates potential deep-seated structural influence.Based on this interpretation, the study area holds significant exploration potential. Key recommendations include ground-truthing, geophysical surveys, and geochemical sampling focused on zones of lineament intersection to refine targets for mineral exploration.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e5.1 Result Discussion\u003c/h2\u003e\u003cp\u003eThis report presents the integrated interpretation of aeromagnetic datasets and structural features across the Boki region in Cross River State, Nigeria. The processed data include the Total Magnetic Intensity (TMI), First Vertical Derivative (1VD), Second Vertical Derivative (2VD), Tilt Derivative, and Lineament Map. These datasets collectively provide insight into the magnetic properties of subsurface rocks, their structural arrangement, and potential zones for mineral exploration within the defined study area. The Total Magnetic Intensity (TMI) map displays variations in magnetic intensity across the area, with the highest anomalies occurring predominantly within and around the study block. These high magnetic values are interpreted as responses from magnetite-rich rock units or intrusive bodies, while the low magnetic zones likely correspond to sedimentary cover or structurally demagnetized zones such as faults. The magnetic anomaly trends observed, particularly the northwest\u0026ndash;southeast and northeast\u0026ndash;southwest alignments, reflect regional tectonic influences and underline the structural complexity of the basement. Further refinement of the magnetic signatures is evident in the First Vertical Derivative (1VD) map, which highlights the shallow and near-surface features by sharpening magnetic boundaries. Within the study area, the 1VD map reveals strong linear anomalies and pronounced gradients, interpreted as lithological contacts, fault boundaries, and zones of fracturing. These features correspond with major geologic discontinuities and provide preliminary indicators of structurally controlled mineralization. The Second Vertical Derivative (2VD) map enhances even finer structural details, offering an intensified view of abrupt magnetic contrasts. The 2VD anomalies occur as narrow, high frequency signatures that likely represent minor fault systems, narrow dykes, or small-scale fractures. These features are especially useful in identifying shallow sources with high exploration potential, particularly where they align or intersect with larger structures observed in the TMI and 1VD maps. The Tilt Derivative map simplifies the interpretation of magnetic contacts by stabilizing amplitude variations across broad anomalies. It delineates well-defined boundaries and enhances both subtle and sharp transitions. The tilt map reveals a network of structurally significant lineaments, many of which pass through or terminate within the study area. These are interpreted as magnetic contacts, faults, or shear zones, and their continuity across the survey area suggests deep-rooted structural control. Complementing the geophysical interpretations is the Lineament Map, which captures structural elements directly from filtered magnetic data. It depicts a dense network of linear features trending predominantly in NW\u0026ndash;SE and NE\u0026ndash;SW directions. The study area hosts several of these lineaments, with some showing clear intersections and clusters. Such areas of structural convergence are geologically significant, as they may serve as conduits for hydrothermal fluids or host zones of mineralization. The central and southern parts of the study block are especially promising, where lineament intersections coincide with magnetic highs and abrupt gradients identified in the derivative maps. Given the results of this interpretation, it is recommended that exploration activities prioritize areas within the study block where high magnetic anomalies align with derivative gradients and lineament intersections. Field validation, supported by ground geophysical surveys such as Induced Polarization (IP) or resistivity, will be crucial for delineating specific\u003c/p\u003e\u003cp\u003etargets. Additionally, geochemical sampling should be carried out in structurally complex zones to confirm mineral presence at the surface or near-surface. In conclusion, the Boki area presents significant exploration potential based on the aeromagnetic and structural interpretations. The convergence of key geophysical anomalies, fault-controlled structures, and defined lineament patterns within the study area supports the presence of subsurface mineralization. Follow-up studies are highly recommended to assess the economic viability of these targets.\u003c/p\u003e\u003c/div\u003e"},{"header":"6. Conclusion","content":"\u003cp\u003eThe integrated interpretation of aeromagnetic, radiometric, and structural data over the Boki area has revealed a geologically favorable environment for mineral exploration. High magnetic anomalies, elevated potassium concentrations, and the presence of numerous intersecting lineaments collectively indicate a structurally complex and potentially mineralized terrain. Within the study area, specific zones,particularly in the northeastern and central parts exhibit signatures consistent with felsic lithologies, potassic alteration, and possible hydrothermal activity. While these remote sensing and geophysical results are promising, they do not independently\u003c/p\u003e\u003cp\u003econfirm the presence of economic mineral deposits. Therefore, systematic ground validation is essential. Through geological mapping, geochemical sampling, and targeted geophysical surveys, the current interpretations can be refined and upgraded into concrete exploration targets. With proper follow-up, the area holds significant potential for the discovery of valuable mineral resources such as gold, rare earth elements, and associated pegmatite-hosted minerals.\u003c/p\u003e"},{"header":"7. Recommendation","content":"\u003cp\u003eThe radiometric and structural analysis within the study block indicates a highly prospective geological setting for mineral exploration. Notably, elevated potassium levels detected in the northeastern portion of the area suggest the presence of felsic rocks like granites, or zones of potassic alteration, both of which are commonly associated with hydrothermal activity and potential mineralization. Additionally, the widespread network of intersecting lineaments across the terrain increases its exploration potential, as such structural features often act as pathways for mineralizing fluids. Nevertheless, while these radiometric signatures are encouraging, they do not serve as conclusive proof of mineral occurrences such as gold or rare earth elements. Therefore, these preliminary findings must be validated and expanded upon through detailed ground-based surveys. Initiate geochemical sampling immediately upon identifying positive field indicators such as Pegmatitic intrusions, alteration zones,Structurally controlled outcrops.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgement:\u003c/strong\u003e Special thanks to the management of Dexter Roy Geoconsult Limited for granting the permission to use the dataset and providing the workstation to interpret the data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eNo funding was received to assist with the preparation of this manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest:\u003c/strong\u003e The authors have no conflicts of interest to declare that are relevant to the content of this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics Statement:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish Declaration:\u003c/strong\u003e All authors has read and agreed to the publication of the original manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate Declaration:\u003c/strong\u003e Not applicable\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eJ.G. and E.P. conceptualize the project, E.P. O.E device the methodology. O.E., O.I. acquire the dataset and analyses, O.E wrote the main manuscript text. O.I., A.M. and L.A. prepared all the figures and maps. R.M., E.P., and J.G. supervise the project and all authors reviewed the manuscript.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe data used in this research can be obtain from the Nigerian Geological Survey Agency.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eObaje, N. G. (2009). Geology and Mineral Resources of Nigeria. Springer.\u003c/li\u003e\n\u003cli\u003eOshin, O. (2020). The geology of Nigeria and its mineral resources. Nigerian Mining Journal, 12(3), 15\u0026ndash;28.\u003c/li\u003e\n\u003cli\u003eKogbe, C. A. (1989). Geology of Nigeria (2nd ed.). Elizabethan Publishing Co.\u003c/li\u003e\n\u003cli\u003eBritish Geological Survey. (2021). Critical raw materials for green energy transition. UK Research and Innovation Report.\u003c/li\u003e\n\u003cli\u003eGarba, I. (2003). Geochemical and geotectonic evolution of Pan-African rare-metal pegmatites in Nigeria. Journal of African Earth Sciences, 37(3\u0026ndash;4), 145\u0026ndash;153. https://doi.org/10.1016/S0899-5362(03)00062-8\u003c/li\u003e\n\u003cli\u003eAkande, S. O., \u0026amp; Abimbola, A. F. (2015). Geological and geochemical constraints on pegmatite mineralization in Nigeria. Nigerian Journal of Mining and Geology, 51(1), 59\u0026ndash;76.\u003c/li\u003e\n\u003cli\u003eU.S. Geological Survey. (2022). Mineral Commodity Summaries 2022: Lithium. U.S. Department of the Interior.\u003c/li\u003e\n\u003cli\u003eOlade, M. A. (1987). Metallogenesis and mineral evaluation of the Pan-African Province of Nigeria. Journal of African Earth Sciences, 6(5), 655\u0026ndash;664. https://doi.org/10.1016/0899-5362(87)90004-1\u003c/li\u003e\n\u003cli\u003eGhosh, S., Roy, A., \u0026amp; Banerjee, S. (2019). Global supply chain analysis of critical minerals in clean energy technologies. Elsevier.\u003c/li\u003e\n\u003cli\u003eOkon, A. O., Etim, E. A., \u0026amp; Ekpo, B. O. (2016). Stream sediment geochemistry and heavy mineral potential of parts of southeastern Nigeria. Natural Resources Research, 25(4), 523\u0026ndash;536. https://doi.org/10.1007/s11053-016-9302-3\u003c/li\u003e\n\u003cli\u003eAbaa, S. I. (1983). The structure and petrography of the Older Granite Suite around Bauchi, northern Nigeria. Journal of African Earth Sciences, 1(1), 39\u0026ndash;44. https://doi.org/10.1016/S0899-5362(83)80030-3\u003c/li\u003e\n\u003cli\u003eSalminen, R., Batista, M. J., Bidovec, M., \u0026amp; Demetriades, A. (2005). Geochemical atlas of Europe: Part 1\u0026mdash;Background information, methodology and maps. Geological Survey of Finland.\u003c/li\u003e\n\u003cli\u003eOdeyemi, I. B. (1981). A review of the orogenic events in the Precambrian Basement of Nigeria. Precambrian Research, 14(3\u0026ndash;4), 177\u0026ndash;188.\u003c/li\u003e\n\u003cli\u003eOdewumi, S. G., Abimbola, A. F., \u0026amp; Yakubu, T. A. (2019). Integrated geophysical mapping of mineralized pegmatite zones in southwestern Nigeria. Journal of Applied Geophysics, 163, 144\u0026ndash;154. https://doi.org/10.1016/j.jappgeo.2019.02.010\u003c/li\u003e\n\u003cli\u003eGarba, I. (2000). Origin of Pan-African rare-metal pegmatites in Nigeria. Mineralium Deposita, 35(2), 208\u0026ndash;221. https://doi.org/10.1007/s001260050229\u003c/li\u003e\n\u003cli\u003eYakubu, T. A., Mohammed, S. B., \u0026amp; Odewumi, S. G. (2022). Aeromagnetic interpretation of pegmatite-hosted rare-metal mineralization in Nigeria. Journal of African Earth Sciences, 195, 104650. https://doi.org/10.1016/j.jafrearsci.2022.104650\u003c/li\u003e\n\u003cli\u003eOden, M. I., Ukaegbu, V. U., \u0026amp; Akpan, A. E. (2021). Integrated geophysical and geological exploration for strategic minerals in southeastern Nigeria. Environmental Earth Sciences, 80(3), 97\u0026ndash;113. https://doi.org/10.1007/s12665-021-09315-7\u003c/li\u003e\n\u003cli\u003eHund, Kirsten; La Porta, Daniele; Fabregas , Thao P; Laing, Tim; Drexhage, John. 2023. Minerals for Climate Action: The Mineral Intensity of the Clean Energy Transition. \u0026copy; World Bank. http://hdl.handle.net/10986/40002 License: CC BY-NC 3.0 IGO.\u0026rdquo;\u003c/li\u003e\n\u003cli\u003eNigerian Geological Survey Agency (2011). Geological Map of Cross River State, Nigeria. Nigerian Geological Survey Agency.\u003c/li\u003e\n\u003cli\u003eRahaman, M. A. (1988). Recent advances in the study of the Basement Complex of Nigeria. In Precambrian Geology of Nigeria (pp. 11\u0026ndash;43). Geological Survey of Nigeria.\u003c/li\u003e\n\u003cli\u003eEkwueme, B. N. (1990). The Precambrian geology and evolution of the Southeastern Nigerian Basement Complex. University of Calabar Press.\u003c/li\u003e\n\u003cli\u003eCaby, R. (1989). Precambrian terranes of Benin\u0026ndash;Nigeria and northeast Brazil and the late Proterozoic South Atlantic fit. Geological Society of America Special Paper, 230, 145\u0026ndash;158. https://doi.org/10.1130/SPE230-p145\u003c/li\u003e\n\u003cli\u003eToteu, S. F., Penaye, J., \u0026amp; Poudjom Djomani, Y. (2004). Geodynamic evolution of the Pan-African Belt in central Africa with special reference to Cameroon. Canadian Journal of Earth Sciences, 41(1), 73\u0026ndash;85. https://doi.org/10.1139/e03-079\u003c/li\u003e\n\u003cli\u003eAjibade, A. C., Woakes, M., \u0026amp; Rahaman, M. A. (1987). Proterozoic crustal development in the Pan-African regime of Nigeria. In Proterozoic Lithospheric Evolution (pp. 259\u0026ndash;271). American Geophysical Union.\u003c/li\u003e\n\u003cli\u003eFerr\u0026eacute;, E. C., Gleizes, G., \u0026amp; Caby, R. (2002). Obliquely convergent tectonics and granite emplacement in the Pan-African belt of Nigeria. Tectonophysics, 361(1\u0026ndash;2), 85\u0026ndash;102. https://doi.org/10.1016/S0040-1951(02)00626-1\u003c/li\u003e\n\u003cli\u003eAjibade, A. C., \u0026amp; Wright, J. B. (1989). The Togo-Benin-Nigeria shield: Evidence of crustal aggregation in the Pan-African belt. Tectonophysics, 165(1\u0026ndash;4), 125\u0026ndash;129. https://doi.org/10.1016/0040-1951(89)90069-0\u003c/li\u003e\n\u003cli\u003eEkwueme, B. N. (2003). The Precambrian geology and evolution of the Southeastern Nigerian Basement Complex. Calabar University Press.\u003c/li\u003e\n\u003cli\u003eOden, M. I., Ukaegbu, V. U., \u0026amp; Akpan, A. E. (2021). Integrated geophysical and geological exploration for strategic minerals in southeastern Nigeria. Environmental Earth Sciences, 80(3), 97\u0026ndash;113. https://doi.org/10.1007/s12665-021-09315-7\u003c/li\u003e\n\u003cli\u003eNigerian Geological Survey Agency (NGSA). (2009). Airborne Geophysical Survey Data of Nigeria. NGSA Publication, Abuja, Nigeria.\u003c/li\u003e\n\u003cli\u003eAnakwuba, E. K., \u0026amp; Onwuemesi, A. G. (2013). Interpretation of aeromagnetic anomalies over parts of the Lower Benue Trough and surrounding areas of southeastern Nigeria. Advances in Applied Science Research, 4(4), 302\u0026ndash;316.\u003c/li\u003e\n\u003cli\u003eReid, A. B., Allsop, J. M., Granser, H., Millet, A. J., \u0026amp; Somerton, I. W. (1990). Magnetic interpretation in three dimensions using Euler deconvolution. Geophysics, 55(1), 80\u0026ndash;91. https://doi.org/10.1190/1.1442774\u003c/li\u003e\n\u003cli\u003eNabighian, M. N. (1972). The analytic signal of two-dimensional magnetic bodies with polygonal cross-section: Its properties and use for automated anomaly interpretation. Geophysics, 37(3), 507\u0026ndash;517. https://doi.org/10.1190/1.1440276\u003c/li\u003e\n\u003cli\u003eRoest, W. R., Verhoef, J., \u0026amp; Pilkington, M. (1992). Magnetic interpretation using the 3-D analytic signal. Geophysics, 57(1), 116\u0026ndash;125. https://doi.org/10.1190/1.1443174\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Geophysical survery, Aeromagnetic signature, Lithium, LCT Pegmatites, Anomaly","lastPublishedDoi":"10.21203/rs.3.rs-8113861/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8113861/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e More attention has been drawn to Nigeria’s solid minerals sector in recent years, in an attempt to divert from over reliance on oil produce to grow its economy. Boki south-south which is a part of the oban massif possess the potential to host economical quantity of lithium due to its geologic and structural settings.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Geophysical survey was employed to map the suspected lithium-rich pegmatic veins in the study area. Aeromagnetic survey was utilised for the survey. the survey was carried out using flight lines spaced at 500 meters, with tie lines at 2- kilometer intervals. An average terrain clearance of 80 meters was maintained to ensure highresolution detection of subsurface features. The flight lines were oriented northwest–southeast (NW–SE), while tie lines followed a northeast–southwest (NE–SW) orientation. Results: A geologically favorable environment for lithium exploration were delineated with high magnetic anomalies, elevated potassium concentrations and presence of numerous intersecting lineaments which all together indicate a structurally complex and potentially mineralized terrain.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e The northeastern and central parts of the study area exhibits signatures consistent with felsic lithologies, potassic alteration, and possible hydrothermal activity.\u003c/p\u003e","manuscriptTitle":"Mapping LCT Pegmatites: An Aeromagnetic Signature for Lithium Mineralization in Boki, South-South, Nigeria","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-12 11:39:58","doi":"10.21203/rs.3.rs-8113861/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7d6adaa6-633a-4ba2-8575-fedd9adc0f51","owner":[],"postedDate":"December 12th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-01T08:42:44+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-12 11:39:58","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8113861","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8113861","identity":"rs-8113861","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}