气候变化领域集成服务门户(CCPortal): The many double BSRs across the northern Hikurangi margin and their implications for subduction processes

CCPortal

DOI	10.1016/j.epsl.2021.116743
	The many double BSRs across the northern Hikurangi margin and their implications for subduction processes
	Han S.; Bangs N.L.; Hornbach M.J.; Pecher I.A.; Tobin H.J.; Silver E.A.
发表日期	2021
ISSN	0012821X
卷号	558
英文摘要	The bottom simulating reflection (BSR) is widely observed along continental margins and is believed to mark the base of gas hydrate stability zone (BGHSZ). In some regions, double or multiple overlapping BSRs are observed, yet their formation mechanisms and geologic implications are not well understood. Here we present 3D seismic images from the 2018 NZ3D experiment that covers a 14×60km2 survey area on New Zealand's northern Hikurangi subduction margin. We observe double BSRs in five locations. Beneath the Tuaheni Basin in the mid-slope, a secondary BSR (BSR2) lies ∼100-360 m deeper than the primary BSR (BSR1) and its 3D geometry mimics the unconformity at the base of the basin. At three thrust ridges located 18-38 km from the deformation front, BSR2 lies ∼55-130 m below and is sub-parallel to BSR1. At another thrust ridge ∼14 km from the deformation front, BSR2 forms above the BSR1, and the two BSRs converge towards the peak of the ridge. Through 3D modeling of BGHSZ and analysis of the geometry and reflection characteristics of the double BSRs, we identify three potential mechanisms for their formation (1) rapid sedimentation, (2) tectonic uplift, (3) overpressure/heat advection caused by fluid migration. Our study demonstrates that formation of double BSRs is closely linked to subduction processes along the northern Hikurangi margin, and double BSRs may be used as indicators for areas with recent sedimentation, tectonic and/or fluid activities. © 2021 Elsevier B.V.
关键词	double bottom-simulating reflections (BSR)fluid migration gas hydrate Hikurangi subduction zone rapid sedimentation tectonic uplift
英文关键词	Deformation; Gas hydrates; Tectonics; Bottom simulating reflection; Formation mechanism; Gas hydrate stability zones; Hikurangi subduction margins; Potential mechanism; Rapid sedimentation; Recent sedimentation; Reflection characteristics; 3D modeling; continental margin; deformation; gas hydrate; sedimentation; subduction zone; tectonic structure; thrust; uplift; Hikurangi Margin; Pacific Ocean
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203114
作者单位	Institute for Geophysics, The University of Texas at Austin, Austin, TX 78758, United States; Southern Methodist University, Dallas, TX 75205, United States; University of Auckland, Auckland, 1010, New Zealand; University of Washington, Seattle, WA 98115, United States; University of California at Santa Cruz, Santa Cruz, CA 95064, United States
推荐引用方式 GB/T 7714	Han S.,Bangs N.L.,Hornbach M.J.,et al. The many double BSRs across the northern Hikurangi margin and their implications for subduction processes[J],2021,558.
APA	Han S.,Bangs N.L.,Hornbach M.J.,Pecher I.A.,Tobin H.J.,&Silver E.A..(2021).The many double BSRs across the northern Hikurangi margin and their implications for subduction processes.Earth and Planetary Science Letters,558.
MLA	Han S.,et al."The many double BSRs across the northern Hikurangi margin and their implications for subduction processes".Earth and Planetary Science Letters 558(2021).