SHARAD study on the structures and permittivity of a buried impact crater in Martian Central Elysium Planitia  

作　　者：Peng FANG Wenzhe FA Jinhai ZHANG Yangting LIN 

机构地区：[1]Key Laboratory of Earth and Planetary Physics,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China [2]Engineering Laboratory for Deep Resources Equipment and Technology,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China [3]College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100029,China [4]Institute of Remote Sensing and Geographical Information System,School of Earth and Space Sciences,Peking University,Beijing 100871,China

出　　处：《Science China Earth Sciences》2023年第11期2452-2462,共11页中国科学（地球科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.41941002);the Key Research Program of the Institute of Geology and Geophysics,CAS(Grant No.IGGCAS-202203);the Key Research Program of the Chinese Academy of Sciences(Grant No.ZDBS-SSW-TLC001);the Open Research Program of the International Research Center of Big Data for Sustainable Development Goals(Grant No.CBAS2022GSP06)。

摘　　要：The Elysium Planitia,located in the transition zone between the northern and southern hemispheres,is one of the key areas for studying the stratigraphic structure and geological history of Mars.Previous studies have shown that this plain has undergone complex surface modification processes including fluvial and volcanic processes,and systematic progress has been made in the study of macro-geological processes.However,there are relatively few studies on the regional structure of the plain,which restricts our understanding of the regional geological processes.A buried impact crater in the central part of the Elysium Planitia could have recorded the surface modification process since the formation of the impact crater,however,it is difficult to distinguish the subsurface stratigraphy due to the weak orbital radar reflection signal.In this study,we denoised Shallow Radar data and obtained a radargram with clear subsurface reflectors.We estimated the permittivity of subsurface materials via a multilayer reflection model.The results show that two subsurface reflectors divide the structure of the buried impact crater into three layers(overlying layer,underlying layer,and bottom layer).The shallow subsurface reflector covers almost the whole impact crater,while the deep subsurface reflector covers only the southwest part of the impact crater.Combining the permittivity inversion results with the geological background of lava activity in the Elysium Planitia area,we argue that the overlying layer may be a mixture of regolith and lava flow with low density,while the underlying layer and bottom layer are dense lava flows.The reflector between the underlying layer and bottom layer is probably a thin deposit derived from weathering between two lava activities,and its possible formation mechanism is as follows:the crater rim and peripheral ejecta has undergone relatively strong wind erosion and the eroded material was transport to the southwestern part of the impact crater,forming continuous thin deposits,between the emplacemen

关 键 词：MARS Elysium Planitia SHARAD Buried crater Permittivity inversion 

分 类 号：P185.3[天文地球—天文学]