Collaborative Research: Solid Earth response of the Patagonia Andes to post-Little Ice Age glacial retreat

GSTDTAP

项目编号	1714662
	Collaborative Research: Solid Earth response of the Patagonia Andes to post-Little Ice Age glacial retreat
	Maria Beatrice Magnani
主持机构	Southern Methodist University
项目开始年	2017
	2017-09-01
项目结束日期	2021-08-31
资助机构	US-NSF
项目类别	Standard Grant
项目经费	514025(USD)
国家	美国
语种	英语
英文摘要	The goal of this project is to understand how the Earth responds to a cryospheric mass imbalance on a time scale of centuries in a compact, well-monitored region of Patagonia, a region of complex Neogene ridge subduction and youthful volcanism. The problem of glacial isostatic adjustment (GIA) is an important problem and critical to understanding the viscosity and time-scales of deformation in the upper mantle. The PI team will try to quantify and model the isostatic response to ice and sediment loading and unloading. A primary driver of modern rock uplift beneath and surrounding the Southern Patagonia Icefield (SPI) is interpreted to be ice loss following the peak advances of the Little Ice Age (LIA). Recent geodetic studies reveal remarkably rapid uplift rates (up to 40 mm/yr and averaging ~20 mm/yr around the SPI). These rates are the fastest modern geologic uplift rates; ones that demand a low viscosity mantle. In Patagonia, the presence of a somewhat poorly understood slab window that developed during Late Cenozoic time supports speculation that a low-viscosity zone underlies the region where GIA is very rapid. This team will explore the causes of high rates and spatial-temporal pattern of the inferred GIA using: (1) a regional broadband seismological array to delineate the crustal and upper mantle structure and viscosity and observe seismicity (currently undefined) along the subducting Austral slab; (2) shipboard reflection seismic data and sediment cores to image and date the young pro- and subglacial sediments deposited in the glacial troughs (now fiord-like lakes) carved by advancing ice with a goal of defining both the geometry of ice and volume of deposited sediment through time; (3) new mapping and dating of the subaerial morainal sequence to define the time-varying spatial geometry of the SPI along its two largest outlet glaciers; and (4) improved geophysical models of glacier and solid earth responses.
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/71909
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Maria Beatrice Magnani.Collaborative Research: Solid Earth response of the Patagonia Andes to post-Little Ice Age glacial retreat.2017.