基于航空地球物理探测的东南极Lambert裂谷—Amery冰架地区冰下环境与地质结构研究

Lambert裂谷—Amery冰架地区具有东南极最大的冰流系统，对该地区开展系统的探测研究具有重要意义。本项研究拟通过对东南极Lambert裂谷—Amery冰架地区实施系统的航空地球物理观测，以揭示冰盖/冰架结构、冰下环境和地质构造的特征和相互关系。通过冰雷探测获取冰厚数据、冰下地形高程和Amery冰架接地线位置，分析Lambert冰川/Amery冰架底部冰下环境特征。通过重力异常和磁异常描述局部地壳的结构特征、地块的趋向性、上地幔的起伏特征、基地岩性特征及分布规律；开展重力和磁法的正反演模拟研究，解析物性异常与地质体形态的关系，研究Lambert裂谷—Amery冰架地区冰下基底的形成机制和沉积年代，推断Lambert裂谷/Amery基底与印度板块Mahanadi盆地和Godavari盆地的构造关系，为了解冈瓦纳大陆裂解的过程提供科学的信息。

It is of great significance to carry out systematic exploration and research on the area of Lambert rift - Amery ice shelf which has the largest ice flow system of the East Antarctica. This proposal aim to build a complete systematic description on aero geophysical exploration for the Lambert rift - Amery ice shelf region, to reveal the characteristics and relationships of structure of the ice sheet /ice shelf, subglacial environment and geological construction. The ice thickness, subglacial topography elevation, the accurate grounding line of Amery shelf are obtained from the aero ice radar, and the subglacial environment characteristics and the processes of change of the Lambert glacier /Amery ice shelf are analyzed. The gravity anomalies and magnetic anomalies are used to describe the structural characteristics of the local crust, the trends of the blocks, the undulating characteristics of the upper mantle, the characteristics and the distribution of the lithologic basement. The forward and inverse modeling of gravity and magnetic is used to analyze the relationship between the physical anomalies and geological body shape. Analyze the formation mechanism and depositional history of subglacial basement for the region of Lambert rift - Amery ice shelf, infer to the relationship between the basement of the Lambert rift/ Amery and the Mahanadi basin & the Godavari basin of the India plate, provide scientific information for the understanding of the breakup of the Gondwana supercontinent.