气候变化领域集成服务门户(CCPortal): Fault zone processes and fluid history in Austin Chalk; Southwest Texas

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DOI	10.1306/04241918168
	Fault zone processes and fluid history in Austin Chalk; Southwest Texas
	Ferrill D.A.; Evans M.A.; McGinnis R.N.; Morris A.P.; Smart K.J.; Lehrmann D.; Gulliver K.D.H.; Sickmann Z.
发表日期	2020
ISSN	0149-1423
起始页码	245
结束页码	283
卷号	104 期号:2
英文摘要	Faults are commonly the largest fractures in a fracture network, forming the backbone of the permeability system in low-permeability rocks. Faults in outcrops of the Austin Chalk - an important oil and gas reservoir in south Texas, Louisiana, and westernmost Mississippi - exemplify deformation and fluid histories of subseismic-scale faults in mechanically layered chalk-dominated strata. Exposures of near-horizontal Austin Chalk in southwest Texas contain northwest- and southeast-dipping normal faults with exposed heights of meters to tens of meters and displacements of centimeters to decimeters. Local fault dips are steep to vertical through chalk and limestone beds and moderate through marl, mud rock, and clay-rich ash beds, producing refracted fault profiles. Failure surface characteristics indicate various failure modes, including tensile, hybrid, shear, and (locally) compactive shear behavior depending on the host lithology. Dilational zones associated with steep fault segments host calcite veins. Crack-seal textures in fault zone veins record repeated reactivation of refracted fault profiles. Fluid inclusion and stable isotope geochemistry analyses of fault veins indicate formation at depths of 1.4 to 2.9 km (4593 to 9514 ft) and possibly of 4.2 km (13,780 ft). Fluids include locally sourced saline waters and externally sourced waters and oil in rocks that did not reach oil maturation conditions. Inclusions of 30° API to greater than 50° API oil are found in veins 30 km (19 mi) updip from the Eagle Ford Formation oil zone. These results illustrate the migration of oil and other fluids within subseismic-scale Austin Chalk faults and fundamental control of lithology on fault zone architecture. © 2020. The American Association of Petroleum Geologists. All rights reserved.
语种	英语
scopus关键词	Calcite; Exploratory geochemistry; Fertilizers; Lime; Lithology; Petroleum reservoir engineering; Petroleum reservoirs; Structural geology; Textures; Failure surface; Fault zone architecture; Fluid inclusion; Fracture network; Fundamental control; Low permeability rock; Oil and gas reservoir; Stable isotopes; Limestone; bedrock; chalk; fault zone; fracture network; geochemical survey; isotopic composition; limestone; marl; permeability; reservoir characterization; seismic response; vein (geology); Louisiana; Texas; United States
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/143728
作者单位	Space Science and Engineering Division, Southwest Research Institute, San Antonio, TX, United States; Department of Geological Sciences, Central Connecticut State University, New Britain, CT, United States; Department of Geosciences, Trinity University, San Antonio, TX, United States; Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX, United States
推荐引用方式 GB/T 7714	Ferrill D.A.,Evans M.A.,McGinnis R.N.,et al. Fault zone processes and fluid history in Austin Chalk; Southwest Texas[J],2020,104(2).
APA	Ferrill D.A..,Evans M.A..,McGinnis R.N..,Morris A.P..,Smart K.J..,...&Sickmann Z..(2020).Fault zone processes and fluid history in Austin Chalk; Southwest Texas.AAPG Bulletin,104(2).
MLA	Ferrill D.A.,et al."Fault zone processes and fluid history in Austin Chalk; Southwest Texas".AAPG Bulletin 104.2(2020).