Free gas distribution and basal shear zone development in a subaqueous landslide – Insight from 3D seismic imaging of the Tuaheni Landslide Complex, New Zealand
Free gas distribution and basal shear zone development in a subaqueous landslide – Insight from 3D seismic imaging of the Tuaheni Landslide Complex, New Zealand
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水下滑坡中的游离气体分布和基底剪切带发育 â 新西兰 Tuaheni 滑坡综合体 3D 地震成像的见解
DOI：
10.1016/j.epsl.2018.09.002
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发表时间：
2018
影响因子：
5.3
通讯作者：
Pecher
中科院分区：
文献类型：
--
作者：
Mountjoy;Crutchley;Böttner;Bialas;Pecher
希库朗吉边缘是新西兰北岛以东的一个活跃大陆边缘。它是公认的地震活跃带，并以浅层沉积物中游离天然气和天然气水合物的存在而闻名。在边缘可以观察到各种水下滑坡，包括贫穷湾附近的Tuaheni滑坡综合体。这个滑坡复合体以前被解释为缓慢蠕动的地貌，因为它的形态和内部变形与陆地泥石流和岩石冰川相当。2014年，我们获得了一个高分辨率的三维地震体，覆盖了Tuaheni南部滑坡的主要部分。三维数据显示了滑前沉积单元和滑坡系统下部单元的多种流体运移指标、游离气聚集和天然气水合物稳定性基础的表现。数据还表明，滑坡系统是由一个上部和下部单元，由内部碎片负极性反射分离。滑坡单元正下方的游离气藏表明，碎屑作为上升流体的边界，在滑坡的远端部分，只有很少的迁移路径到碎屑内反射层。滑坡的碎片内的变形集中在上部滑坡单元，我们解释内的碎片反射层作为一个基础剪切带或“滑动面”上的碎片已被重新激活。碎片内反射层的起源尚不清楚，但我们认为它可能是一个相对粗粒的层位，易于流体流动集中和过度流体压力的发展。我们的地震研究提供了一个水下滑坡系统的最详细的例子之一，揭示了流体流动系统和潜在的基底剪切带的Tuaheni滑坡复杂的发展的见解。
The Hikurangi margin is an active continental margin east of New Zealand's North Island. It is well recognized as a seismically active zone and is known for the occurrence of free gas and gas hydrates within the shallow sediments. A variety of subaqueous landslides can be observed at the margin, including the Tuaheni Landslide Complex off Poverty Bay. This slide complex has been interpreted previously as a slowly creeping landform, as its morphology and internal deformation is comparable to terrestrial earthflows and rock glaciers. In 2014, we acquired a high-resolution 3D seismic volume covering major parts of the Tuaheni South landslide. The 3D data show a variety of fluid migration indicators, free gas accumulations and manifestations of the base of gas hydrate stability in the pre-slide sedimentary units and the lower unit of the landslide system. The data also show that the landslide system is composed of an upper and lower unit that are separated by an intra-debris negative-polarity reflection. Free gas accumulations directly beneath the landslide units suggest that the debris acts as a boundary for rising fluids and only few migration pathways to the intra-debris reflector are observed in the distal parts of the landslide. Deformation within the landslide's debris is focused in the upper landslide unit, and we interpret the intra-debris reflector as a basal shear zone or ‘glide plane’ upon which the debris has been remobilized. The origin of the intra-debris reflector is unclear, but we suggest it could be a relatively coarse-grained horizon that would be prone to fluid flow focusing and the development of excess fluid pressure. Our seismic study provides one of the most detailed examples of a subaqueous landslide system and reveals insights into the fluid flow system and potential basal shear zone development of the Tuaheni Landslide Complex.
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影响因子：
16.6
作者：
Elger J;Berndt C;Rüpke L;Krastel S;Gross F;Geissler WH
通讯作者：
Geissler WH
浅层气体和海底扩散过程中薄弱层的形成，Hikurangi 边缘（新西兰）
DOI：
10.1007/978-3-319-20979-1_42
发表时间：
2016
期刊：
影响因子：
--
作者：
Micallef;Mountjoy;Krastel;Crutchley
通讯作者：
Crutchley
沉积混杂岩中与质量传输相关的地层破坏：来自亚平宁山脉北部（意大利）和比利牛斯山脉中南部（西班牙）的例子
DOI：
--
发表时间：
2012
期刊：
影响因子：
--
作者：
K. Ogata;E. Mutti;G. Pini;R. Tinterri
通讯作者：
R. Tinterri
质量传输沉积物的高分辨率研究：了解现代海底斜坡破坏和相关自然灾害的露头视角
DOI：
10.1007/978-3-319-08660-6_40
发表时间：
2014
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
K. Ogata;G. Pini;A. Festa;Ž. Pogačnik;Giorgio Tunis;J. Mountjoy;K. Senger;M. Strasser
通讯作者：
M. Strasser
影响因子：
2.9
作者：
A. Orpin
通讯作者：
A. Orpin