气候变化领域集成服务门户(CCPortal): Effect of Plate Length on Subduction Kinematics and Slab Geometry: Insights From Buoyancy-Driven Analog Subduction Models

CCPortal

DOI	10.1029/2020JB020514
	Effect of Plate Length on Subduction Kinematics and Slab Geometry: Insights From Buoyancy-Driven Analog Subduction Models
	Xue K.; Schellart W.P.; Strak V.
发表日期	2020
ISSN	21699313
卷号	125 期号:11
英文摘要	Subduction style is controlled by a variety of physical parameters. Here we investigate the effect of subducting plate length on subduction style using laboratory experiments of time-evolving buoyancy-driven subduction in 3-D space. The investigation includes two experimental sets, one with a lower (~740) and one with a higher (~1,680) subducting plate-to-mantle viscosity ratio (ηSP/ηM). Each set involves five models with a free-trailing-edge subducting plate and variable plate length (20–60 cm, scaling to 1,600–4,800 km), and one model with a fixed-trailing-edge subducting plate representing an infinitely long plate. Through determining the contact area between subducting plate and underlying mantle, plate length affects the resistance to trenchward motion of the subducting plate and thus controls the partitioning of the subduction velocity (vS) into the subducting plate velocity (vSP) and trench velocity (vT). This subduction partitioning thereby determines the subduction style by controlling the dip angle of the slab tip once it first touches the 660 km discontinuity. The low ηSP/ηM models display two subduction styles. Short plates (≤40 cm) induce a higher subduction partitioning ratio (vSP/vS), promoting trench advance and slab rollover geometries, whereas longer plates (≥50 cm) lead to a lower vSP/vS, producing continuous trench retreat and backward slab draping geometries. In contrast, the high ηSP/ηM models exclusively show trench retreat with draping geometries, as the high ηSP/ηM enables less slab bending before its tip touches the 660 km discontinuity. Our study indicates that future modeling work should consider the effects of plate length on the style and evolution of subduction. ©2020. The Authors.
英文关键词	geodynamics; plate kinematics; slab bending; slab dip; subduction; trench migration
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187511
作者单位	Department of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
推荐引用方式 GB/T 7714	Xue K.,Schellart W.P.,Strak V.. Effect of Plate Length on Subduction Kinematics and Slab Geometry: Insights From Buoyancy-Driven Analog Subduction Models[J],2020,125(11).
APA	Xue K.,Schellart W.P.,&Strak V..(2020).Effect of Plate Length on Subduction Kinematics and Slab Geometry: Insights From Buoyancy-Driven Analog Subduction Models.Journal of Geophysical Research: Solid Earth,125(11).
MLA	Xue K.,et al."Effect of Plate Length on Subduction Kinematics and Slab Geometry: Insights From Buoyancy-Driven Analog Subduction Models".Journal of Geophysical Research: Solid Earth 125.11(2020).