气候变化领域集成服务门户(CCPortal): Differential compaction over Late Miocene submarine channels in SE Brazil: Implications for trap formation

CCPortal

DOI	10.1130/B31659.1
	Differential compaction over Late Miocene submarine channels in SE Brazil: Implications for trap formation
	Ward N.I.P.; Alves T.M.; Blenkinsop T.G.
发表日期	2018
ISSN	167606
起始页码	208
结束页码	221
卷号	130 期号:2021-01-02
英文摘要	We used high-quality three-dimensional (3-D) seismic data to quantify the timing and magnitude of differential compaction over a Late Miocene submarine channel complex in SE Brazil (Espírito Santo Basin). A thicknessrelief method was applied to quantify the thickness variations in strata deposited over the channel complex. We found that differential compaction started after the channel complex was buried by ~200 m of strata, as revealed by thinning horizons observed over a compaction-related anticline. The size of the anticline is greatest in the south of the study area, reaching heights of 41 ms (~50 m). Fluid expelled through faults on the margins of the channel complex formed large depressions. These depressions increased in size after deep-water currents removed the fluid-rich sediment filling them. Differential compaction also occurred over deposits downslope of knickpoints, reaching maximum heights of 29 ms (~35 m). Seismic reflections onlap the knickpoint face and are believed to comprise slumped strata and debrites. Two-way traveltime isochron and amplitude maps indicate that there are limited connectivity and lateral continuity of the coarse-grained units. Differential compaction over these deposits created anticlines with four-way dip closure. As a consequence, isolated reservoirs were closed vertically by the compaction anticlines and laterally by strata onlapping the knickpoint face. These unique reservoirs could have been charged by migration of hydrocarbons along sands at the base of the channel complex. A fill-to-spill model is hypothesized using the above mechanism: Once an isolated anticlinal trap reached spill point, hydrocarbons migrated upslope into the next trap. Traps like these could form above submarine channels in similar basins around the world (e.g., Gulf of Mexico, west coast of Africa) after early burial. © 2017 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185102
作者单位	3D Seismic Laboratory, School of Earth and Ocean Sciences, Cardiff University, Main Building Park Place, Cardiff, CF10 3AT, United Kingdom
推荐引用方式 GB/T 7714	Ward N.I.P.,Alves T.M.,Blenkinsop T.G.. Differential compaction over Late Miocene submarine channels in SE Brazil: Implications for trap formation[J],2018,130(2021-01-02).
APA	Ward N.I.P.,Alves T.M.,&Blenkinsop T.G..(2018).Differential compaction over Late Miocene submarine channels in SE Brazil: Implications for trap formation.Bulletin of the Geological Society of America,130(2021-01-02).
MLA	Ward N.I.P.,et al."Differential compaction over Late Miocene submarine channels in SE Brazil: Implications for trap formation".Bulletin of the Geological Society of America 130.2021-01-02(2018).