Study on Wellbore Instability Considering the Weak Plane- Seepage-Stress Coupled Effect

Study on Wellbore Instability Considering the Weak Plane- Seepage-Stress Coupled Effect | 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 Article Study on Wellbore Instability Considering the Weak Plane- Seepage-Stress Coupled Effect Yang Wang, Zhibo Wang, Lin Zhong, Zhiming Xu, Huaqing Wu, Jiang Feng This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8942921/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 12 You are reading this latest preprint version Abstract Wellbore instability is a critical challenge in deep and unconventional oil and gas drilling, with mechanisms particularly complex in fractured reservoirs due to the coupling effects of weak planes, seepage, and stress. Conventional models struggle to accurately describe wellbore instability under conditions involving multiple weak planes and anisotropic seepage. This study establishes a weak plane-seepage-stress coupling model, integrating in-situ stress, wellbore trajectory, and fracture orientation through coordinate system transformation. The weak plane strength criterion and Newton's iterative method are employed to predict wellbore collapse pressure. Results indicate that the presence of weak planes significantly disrupts the symmetry of stress distribution around the wellbore, leading to highly heterogeneous collapse pressure contours. Wellbore stability is primarily controlled by weak plane orientation, with the optimal drilling direction ranging from 200° to 280°. Meanwhile, the sealing efficiency of drilling fluid, characterized by the seepage coefficient δ, exerts a notable influence on wellbore stability: as δ increases from 0 (no sealing) to 1 (complete sealing), the collapse pressure decreases significantly, with the improvement being particularly pronounced under high sealing efficiency. Changes in the seepage field interact synergistically with the geometric attributes of weak planes, affecting the spatial distribution of collapse pressure. This study clearly demonstrates that enhancing wellbore sealing is the most effective engineering measure to control wellbore instability, providing an important theoretical basis for safe drilling design in fractured formations. Physical sciences/Engineering Earth and environmental sciences/Natural hazards Earth and environmental sciences/Solid earth sciences Weak planes Seepage-stress coupling In-situ stress Building foundation stability Underground construction Engineering design Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 23 Apr, 2026 Reviews received at journal 22 Apr, 2026 Reviewers agreed at journal 13 Apr, 2026 Reviewers agreed at journal 12 Apr, 2026 Reviews received at journal 13 Mar, 2026 Reviewers agreed at journal 07 Mar, 2026 Reviewers agreed at journal 06 Mar, 2026 Reviewers invited by journal 06 Mar, 2026 Editor invited by journal 05 Mar, 2026 Editor assigned by journal 02 Mar, 2026 Submission checks completed at journal 02 Mar, 2026 First submitted to journal 22 Feb, 2026 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-8942921","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":602341104,"identity":"d8d2e2db-edda-4c53-a3d6-64c9087877a3","order_by":0,"name":"Yang 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Conventional models struggle to accurately describe wellbore instability under conditions involving multiple weak planes and anisotropic seepage. This study establishes a weak plane-seepage-stress coupling model, integrating in-situ stress, wellbore trajectory, and fracture orientation through coordinate system transformation. The weak plane strength criterion and Newton's iterative method are employed to predict wellbore collapse pressure. Results indicate that the presence of weak planes significantly disrupts the symmetry of stress distribution around the wellbore, leading to highly heterogeneous collapse pressure contours. Wellbore stability is primarily controlled by weak plane orientation, with the optimal drilling direction ranging from 200\u0026deg; to 280\u0026deg;. Meanwhile, the sealing efficiency of drilling fluid, characterized by the seepage coefficient δ, exerts a notable influence on wellbore stability: as δ increases from 0 (no sealing) to 1 (complete sealing), the collapse pressure decreases significantly, with the improvement being particularly pronounced under high sealing efficiency. Changes in the seepage field interact synergistically with the geometric attributes of weak planes, affecting the spatial distribution of collapse pressure. This study clearly demonstrates that enhancing wellbore sealing is the most effective engineering measure to control wellbore instability, providing an important theoretical basis for safe drilling design in fractured formations.\u003c/p\u003e","manuscriptTitle":"Study on Wellbore Instability Considering the Weak Plane- Seepage-Stress Coupled Effect","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-11 18:47:15","doi":"10.21203/rs.3.rs-8942921/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-23T08:25:46+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-22T07:10:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"221459181021043000024646704834912121109","date":"2026-04-13T15:18:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"258355117832865748882519456182021994227","date":"2026-04-12T12:39:44+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-13T07:30:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"295580539573718698859540560015862938186","date":"2026-03-07T13:15:33+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"289704152135359152546533336967977666954","date":"2026-03-06T09:22:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-06T09:09:52+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-05T17:59:21+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-03T01:56:20+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-03T01:55:25+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-02-23T04:43:54+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"836201e6-67ee-489c-9224-f2745b95a485","owner":[],"postedDate":"March 11th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[{"id":64102640,"name":"Physical sciences/Engineering"},{"id":64102641,"name":"Earth and environmental sciences/Natural hazards"},{"id":64102642,"name":"Earth and environmental sciences/Solid earth sciences"}],"tags":[],"updatedAt":"2026-04-23T08:40:29+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-11 18:47:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8942921","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8942921","identity":"rs-8942921","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}