Improving the Locations of Local/Regional Earthquakes Using the Circle Method with Fuzzy Logic

Improving the Locations of Local/Regional Earthquakes Using the Circle Method with Fuzzy Logic | 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 Improving the Locations of Local/Regional Earthquakes Using the Circle Method with Fuzzy Logic Hüseyin GÖKALP This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7141712/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract In this study, the hypocenter location method based on the “circle method,” developed with a fuzzy logic approach, was used to resolve local/regional earthquake locations. To evaluate the performance and usefulness of the method in various situations, it was initially tested on synthetic models. After gaining experience, it was tested on real earthquake data. Three artificial seismic networks with different station distribution geometries were selected to investigate the effect of network shape on the solution. Additionally, all networks took into account the earthquake's proximity to the networks, whether the earthquake was inside, near, or far away from them. The hypocenter location was determined in three ways within the same method. One approach involved defuzzifying the output of the intersection process on three fuzzy logic output matrices. The second method applied defuzzification only to the grid points with the highest fuzzy output values. The last method used defuzzification on values of 1 obtained through a normalization process based on the highest membership value among the fuzzy outputs. While the results for earthquakes occurring away from the network were considered slightly more successful, in these cases, the volumes of the fuzzy logic output matrices being processed significantly increased, leading to much longer computation times. The proposed method was used to estimate the hypocenter locations of 122 shallow earthquakes that occurred in the eastern Black Sea region and was found to produce results comparable to those obtained by other seismic agencies. Compared to classical methods, most earthquakes show an average total spatial difference of approximately 5 km. This method is considered highly effective for local earthquakes within the station network, as well as for regional earthquakes occurring outside the network, particularly when the hypocenter-station distance is significantly greater than the distances between stations, resulting in substantial azimuthal gaps. Earthquake location circle method hypocenter fuzzy logic eastern Black Sea earthquakes Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 10 Sep, 2025 Reviews received at journal 10 Sep, 2025 Reviewers agreed at journal 30 Aug, 2025 Reviews received at journal 29 Aug, 2025 Reviewers agreed at journal 03 Aug, 2025 Reviewers invited by journal 24 Jul, 2025 Editor assigned by journal 23 Jul, 2025 Submission checks completed at journal 23 Jul, 2025 First submitted to journal 16 Jul, 2025 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. 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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-7141712","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":486439309,"identity":"97df3ef2-dede-46f4-8f6c-2b1fee678400","order_by":0,"name":"Hüseyin GÖKALP","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAx0lEQVRIiWNgGAWjYFACNgaGBww2BmA2D9FaEhjSDHigWiSI1XKYBC3y7m2JHxJ3nDe2l0hgfPC2jaHOvIGAFsMzxw5LJJ65bcYjkcBsOLeNQULmACEtM9IbJBLbbtsAtbBJ8wK1EHQZUEvzj8S2cyAt7L+J0iIvkXYMaMsBkMPYmInSYsBzLM0i8UyyMc+Zh82Sc85JSM4gaEt7m/GNjzvsDNvbkw9+eFNmw0/YlgNAgrGBAUYSEZPyDXAto2AUjIJRMApwAAAJCzld1xSPrgAAAABJRU5ErkJggg==","orcid":"","institution":"Karadeniz Technical University","correspondingAuthor":true,"prefix":"","firstName":"Hüseyin","middleName":"","lastName":"GÖKALP","suffix":""}],"badges":[],"createdAt":"2025-07-16 15:38:53","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7141712/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7141712/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":86931976,"identity":"34f3360a-a393-4566-b392-368659ee2d17","added_by":"auto","created_at":"2025-07-17 09:53:29","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4438229,"visible":true,"origin":"","legend":"","description":"","filename":"HseyinGkalpCirclemethodwithfuzzylogicfinalctedfinal.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7141712/v1_covered_455459a0-64fe-45f9-b8e8-fff5e22d7f78.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eImproving the Locations of Local/Regional Earthquakes Using the Circle Method with Fuzzy Logic\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-seismology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jose","sideBox":"Learn more about [Journal of Seismology](http://link.springer.com/journal/10950)","snPcode":"10950","submissionUrl":"https://submission.nature.com/new-submission/10950/3","title":"Journal of Seismology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Earthquake location, circle method, hypocenter, fuzzy logic, eastern Black Sea earthquakes","lastPublishedDoi":"10.21203/rs.3.rs-7141712/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7141712/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"In this study, the hypocenter location method based on the “circle method,” developed with a fuzzy logic approach, was used to resolve local/regional earthquake locations. 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