气候变化领域集成服务门户(CCPortal): Mini thief zones: Subcentimeter sedimentary features enhance fracture connectivity in shales

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DOI	10.1306/0918181610617114
	Mini thief zones: Subcentimeter sedimentary features enhance fracture connectivity in shales
	McCay A.T.; Shipton Z.K.; Lunn R.J.; Gale J.F.
发表日期	2019
ISSN	0149-1423
卷号	103 期号:4
英文摘要	This study examines the influences on fluid flow within a shale outcrop where the networks of two distinct paleoflow episodes have been recorded by calcite-filled veins and green alteration halos. Such direct visualization of flow networks is relatively rare and provides valuable information of fluid-flow behavior between core and seismic scale. Detailed field mapping, fracture data, and sedimentary logging were used over a 270 m2 (2910 ft2) area to characterize the paleo–fluid-flow networks in the shale. Distal remnants of turbidite flow deposits are present within the shale as very thin (1–10 mm [0.04–0.4 in.]) fine-grained sandstone bands. The shale is cut by a series of conjugate faults and an associated fracture network, all at a scale smaller than seismic detection thresholds. The flow episodes used fluid-flow networks consisting of subgroups of both the fractures and the thin turbidites. The first fluid-flow episode network was mainly comprised of thin turbidites and shear fractures, whereas the network of the second fluid-flow episode was primarily small joints (opening mode fractures) connecting the turbidites. The distribution of turbidite thicknesses follows a negative exponential trend. which reflects the distribution of thicker turbidites recorded in previous studies. Fracture density varies on either side of faults and is highest in an area between closely spaced faults. Better predictions of hydraulic properties of sedimentary-structural networks for resource evaluation can be informed from such outcrop subseismic scale characterization. These relationships between the subseismic features could be applied when populating discrete fracture networks models, for example, to investigate such sedimentary-structural flow networks in exploration settings. Copyright ©2019. The American Association of Petroleum Geologists. All rights reserved.
语种	英语
scopus关键词	Calcite; Fracture; Sedimentology; Seismology; Shale; Shear flow; Direct visualization; Discrete fracture network; Fracture connectivity; Hydraulic properties; Negative exponential; Opening mode fracture; Resource evaluation; Scale characterization; Flow of fluids; calcite; connectivity; fine grained sediment; fluid flow; fracture; logging (geophysics); outcrop; paleohydrology; sandstone; sedimentary basin; shale; turbidite; vein (geology); visualization
来源期刊	AAPG Bulletin
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/125030
作者单位	Engineering Geosciences and Geomechanics, Department of Civil and Environmental Engineering, University of Strathclyde, Glasgow, United Kingdom; Systems, Power and Energy Research Division, School of Engineering, University of Glasgow, Glagsow, United Kingdom; Bureau of Economic Geology, University of Texas at Austin, Austin, TX, United States
推荐引用方式 GB/T 7714	McCay A.T.,Shipton Z.K.,Lunn R.J.,et al. Mini thief zones: Subcentimeter sedimentary features enhance fracture connectivity in shales[J],2019,103(4).
APA	McCay A.T.,Shipton Z.K.,Lunn R.J.,&Gale J.F..(2019).Mini thief zones: Subcentimeter sedimentary features enhance fracture connectivity in shales.AAPG Bulletin,103(4).
MLA	McCay A.T.,et al."Mini thief zones: Subcentimeter sedimentary features enhance fracture connectivity in shales".AAPG Bulletin 103.4(2019).