دورية أكاديمية

Paleo‐Permeability Structure of the Crustal Section of the Samail Ophiolite Based on Automated Detection of Veins in X‐Ray CT Core Images From the Oman Drilling Project

التفاصيل البيبلوغرافية
العنوان: Paleo‐Permeability Structure of the Crustal Section of the Samail Ophiolite Based on Automated Detection of Veins in X‐Ray CT Core Images From the Oman Drilling Project
المؤلفون: Y. Akamatsu, I. Katayama, K. Okazaki, K. Michibayashi
المصدر: Geochemistry, Geophysics, Geosystems, Vol 24, Iss 6, Pp n/a-n/a (2023)
بيانات النشر: Wiley, 2023.
سنة النشر: 2023
المجموعة: LCC:Geophysics. Cosmic physics
LCC:Geology
مصطلحات موضوعية: permeability, oceanic crust, hydrothermal circulation, X‐ray computed tomography, image processing, Oman Drilling Project, Geophysics. Cosmic physics, QC801-809, Geology, QE1-996.5
الوصف: Abstract To assess the paleo‐permeability structure of oceanic crust, we used 3‐D X‐ray Computed Tomography (XCT) images to quantify the distribution and geometry of mineral veins in core samples from Oman Drilling Project Holes GT1A, GT2A, and GT3A, which correspond to the upper to lower crustal sections of the Samail ophiolite. We developed a new method that automatically detects veins in the XCT core images based on iterative adaption of the two‐step Hough transform combined with multiscale Hessian filtering for identifying an elongate structure. Application of the developed method allowed us to identify the geometry and Computed Tomography number of more than 1500 veins with millimeter‐scale apertures in core sections with a total length of ∼1,200 m. High‐CT (HCT) veins in the drilled cores can be related to relatively high‐temperature fluid circulation near the mid‐ocean ridge, whereas Low‐CT (LCT) veins can be related to subsequent low‐temperature fluid circulation. Applying fracture fluid‐flow models to the geometric information for the detected veins, we found that the HCT and LCT vein systems both yielded bulk permeability of 10−13–10−9 m2 for each hole. This indicates that millimeter‐wide fractures can control crustal‐scale permeability, even in the lower oceanic crust. However, these vein systems show different depth dependencies and anisotropies of permeability, possibly reflecting the different spatial variations of high‐ and low‐temperature fluid circulation in oceanic crust.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1525-2027
العلاقة: https://doaj.org/toc/1525-2027Test
DOI: 10.1029/2022GC010792
الوصول الحر: https://doaj.org/article/46d2e18ca86f43afbf042623c3e56424Test
رقم الانضمام: edsdoj.46d2e18ca86f43afbf042623c3e56424
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:15252027
DOI:10.1029/2022GC010792