Constraining paleo-dynamics and sediment transport of Antarctic stream flow across grounding lines - from source to sink

限制南极溪流穿过接地线的古动力学和沉积物输送——从源头到汇

基本信息

批准号：
275409824
负责人：
Professor Dr. Todd Alan Ehlers
金额：
--
依托单位：
Alfred-Wegener-Institut (AWI) Helmholtz-Zentrum für Polar- und Meeresforschung
依托单位国家：
德国
项目类别：
Infrastructure Priority Programmes
财政年份：
2015
资助国家：
德国
起止时间：
2014-12-31 至 2019-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/275409824?language=en
关键词：
Constraining paleo dynamics sediment transport

项目摘要

This interdisciplinary project integrates high-resolution seismic imaging with numerical models of ice dynamics, erosion, and sediment transport to quantify past and present interactions between glaciers and the solid Earth. In doing this, we test the hypothesis that sub-ice sediment production, transport, and deposition are key controls on past and present day ice dynamics and stability in Antarctica. We will produce a physics based understanding of how ice flow interacts with the solid earth by comprehensivly employing a source-to-sink concept within one of the best geographically constrained glacial catchments, the Ekströmisen in Dronning Maud Land, Antarctica. Within the contemporary discussion of climate change, ice sheet stability, and paleoclimatic conditions, we will contribute to answering the following imminent scientific questions: How did Antarctic drainage basins behave during several glacial cycles? How did grounded ice retreat into the Holocence? What are the governing basal conditions for ice stream flow in drainage basins? To what degree do erosional and depositional processes and underlying strata influence ice dynamics and stability? To address these questions, we will integrate existing seismic data of subglacial strata (e.g. geomorphology and sediment basins) with aero-geophysical information (ice thickness and englacial stratigraphy from radar, geology from gravimetry and magnetics) and satellite remote sensing products (surface elevation and ice-flow velocity). A higher-order numerical ice-flow and subglacial hydrology model will be used to quantify Ekströmisens ice-flow dynamics. Initial conditions (distribution of liquid water, and properties of basal sediment and bedrock) will be derived from radar and seismic data. Ice flow simulations will be coupled with a numerical model for glacial erosion, transport and deposition. These models will quantify the development of Ekströmisens catchment areas geometry, mass transport and basal conditions over multiple glacial-interglacial cycles and enable investigation of possible feedbacks between basal sediment and ice dynamics. Observed sedimentary structure and core records are used to validate the simulated flow behaviour and erosion/sedimentation processes. Taking advantage of the Ekström basins confined geometry, the project will overcome the limitation of previous large-scale sediment source-to-sink studies with multiple source areas and unconfined deposition zones. We will quantify in unprecedented detail ice-dynamic interactions with the underlying strata and the coupling between glacial and solid Earth systems.

这个跨学科的项目将高分辨率的地震成像与冰动力学，侵蚀和沉积物传输的数值模型相结合，以量化冰川与固体地球之间的过去和现在相互作用。在此过程中，我们检验了一个假设，即亚冰沉积物的产生，运输和沉积是过去和现在的南极冰动力学和稳定性的关键控制。我们将通过在最佳地理位置约束的冰川流域之一，即Dronning Maud Land，Antarctica中的Ekströmisen中全面地采用源头对链接概念来对冰流如何与固体地球相互作用。在当代关于气候变化，冰盖稳定性和古气候条件的讨论中，我们将为回答以下即将到来的科学问题做出贡献：在几个冰川周期中，南极排水鲈鱼的表现如何？将冰撤退到整个全体状态是如何将其陷入困境的？排水低音中冰流的基本条件是什么？侵蚀和沉积过程以及基础地层在多大程度上影响冰的动力学和稳定性？为了解决这些问题，我们将将现有的地震数据（例如地貌和沉积物贝斯）与空气地面物理信息（来自雷达的冰厚度和英语层次造影，地质学的地质学和磁石）以及卫星远程感应产物（表面Everation and Ice-Flow Velocity）结合在一起。高阶数值冰流和冰河水文学模型将用于量化Ekströmisens冰流动力学。初始条件（液态水的分布以及基本沉积物和基岩的特性）将源自雷达和地震数据。冰流模拟将与用于冰川侵蚀，运输和沉积的数值模型相结合。这些模型将量化Ekströmsens集水区域的几何形状，大规模运输和基本条件的发展，并在多个冰川间冰期循环中的发展，并能够在基本沉积物和冰动力学之间投资可能的反馈。观察到的沉积结构和核心记录用于验证模拟的流动行为和侵蚀/沉积过程。利用EkströmBasses限制了几何形状，该项目将克服具有多个源区域和未限定沉积区域的先前大规模沉积物源对链接研究的限制。我们将以前所未有的细节与基础地层以及冰川和固体地球系统之间的耦合进行量化的冰脱水相互作用进行量化。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Bathymetry Beneath Ice Shelves of Western Dronning Maud Land, East Antarctica, and Implications on Ice Shelf Stability

DOI：
10.1029/2019gl086724
发表时间：
2020-06-28
期刊：
GEOPHYSICAL RESEARCH LETTERS
影响因子：
5.2
作者：
Eisermann, Hannes;Eagles, Graeme;Jokat, Wilfried
通讯作者：
Jokat, Wilfried

Detailed Seismic Bathymetry Beneath Ekström Ice Shelf, Antarctica: Implications for Glacial History and Ice‐Ocean Interaction

南极洲埃克斯特罗姆冰架下详细的地震测深：对冰川历史和冰海相互作用的影响

DOI：
10.1029/2019gl086187
发表时间：
期刊：
Geophysical Research Letters
影响因子：
5.2
作者：
Hattermann;Gaedicke;Berger;Ehlers;T. A. ;Franke;Gromig;Hofstede;Lambrecht;Laeufer;Tiedemann;Wilhelms
通讯作者：
Wilhelms

Coring of Antarctic Subglacial Sediments