Both Longitudinal and Transverse Extension Controlling Gas Migration Through Submarine Anticlinal Ridges, New Zealand's Southern Hikurangi Margin

Author:

Crutchley Gareth J.1ORCID,Hillman Jess I. T.2ORCID,Kroeger Karsten F.2ORCID,Watson Sally J.34ORCID,Turco Francesco5,Mountjoy Joshu J.3ORCID,Davy Bryan2ORCID,Woelz Susi3ORCID

Affiliation:

1. GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany

2. GNS Science Wellington New Zealand

3. National Institute of Water and Atmospheric Research (NIWA) Wellington New Zealand

4. Institute of Marine Science University of Auckland Auckland New Zealand

5. University of Otago Dunedin New Zealand

Abstract

AbstractSub‐seabed fluid flow, gas hydrate accumulation and seafloor methane seepage are tightly interwoven processes with implications for marine biodiversity, ocean chemistry and seafloor stability. We combine long‐offset seismic reflection data with high‐resolution seismic data to investigate shallow structural deformation and its relationship to focused gas migration and hydrate accumulation in the southern Hikurangi subduction wedge. Anticlines, effective traps for focusing free gas, are characterized by both normal faults and vertical zones of hydraulic fracturing within the hydrate stability zone. The normal faults form as a result of sediment layer folding and gravitational collapse of ridges during uplift. We document both longitudinal (ridge‐parallel) and transverse (ridge‐perpendicular) extensional structures (normal faults and elongated hydraulic fracture zones) in the sub‐seafloor of anticlinal ridges. Intriguingly, gas flow through ridges close to the deformation front of the wedge exploits longitudinal structures, while ridges further inboard are characterized by gas flow along transverse structures. This highlights pronounced changes in the shallow deformation of ridges in different parts of the wedge, associated with a switching of the least and intermediate principal stress directions. It is critical to understand these shallow stress fields because they control fluid flow patterns and methane seepage out of the seafloor.

Funder

Ministry for Business Innovation and Employment

Publisher

American Geophysical Union (AGU)

Subject

Space and Planetary Science,Earth and Planetary Sciences (miscellaneous),Geochemistry and Petrology,Geophysics

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3