Retrieving volume FeO and TiO_2 abundances of lunar regolith with CE-2 CELMS data using BPNN method

作     者：Cai Liu Hong-Yan Sun Zhi-Guo Meng Yong-Chun Zheng Yu Lu Zhan-Chuan Cai Jin-Song Ping Alexander Gusev Shuo Hu 

作者机构：College of Geoexploration Science and Technology Jilin University State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and Technology Key Laboratory of Lunar and Deep Space Exploration National Astronomical Observatories Chinese Academy of Sciences School of Geography and Ocean Science Nanjing University Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Institute of Geology Kazan Federal University 

出 版 物：《Research in Astronomy and Astrophysics》 (天文和天体物理学研究（英文版）)

年 卷 期：2019年第19卷第5期

页      面：31-42页

核心收录：

学科分类：07[理学] 

基　　金：supported in part by the Key Research Program of the Chinese Academy of Sciences under Grant (XDPB11) in part by opening fund of State Key Laboratory of Lunar and Planetary Sciences (Macao University of Science and Technology) (Macao FDCT Grant No. 119/2017/A3) in part by the National Natural Science Foundation of China (Grant Nos. 41490633, 41371332 and 41802246) in part by the Science and Technology Development Fund of Macao (Grant 0012/2018/A1) 

主　　题：planetary systems Moon evolution imaging spectroscopy data analysis 

摘      要：The volume FeO and TiO_2 abundances(FTAs) of lunar regolith can be more important for understanding the geological evolution of the Moon compared to the optical and gamma-ray results. In this paper, the volume FTAs are retrieved with microwave sounder(CELMS) data from the Chang E-2 satellite using the back propagation neural network(BPNN) method. Firstly, a three-layered BPNN network with five-dimensional input is constructed by taking nonlinearity into account. Then, the brightness temperature(TB) and surface slope are set as the inputs and the volume FTAs are set as the outputs of the BPNN ***, the BPNN network is trained with the corresponding parameters collected from Apollo, Luna,and Surveyor missions. Finally, the volume FTAs are retrieved with the trained BPNN network using the four-channel TBderived from the CELMS data and the surface slope estimated from Lunar Orbiter Laser Altimeter(LOLA) data. The rationality of the retrieved FTAs is verified by comparing with the Clementine UV-VIS results and Lunar Prospector(LP) GRS results. The retrieved volume FTAs enable us to re-evaluate the geological features of the lunar surface. Several important results are as follows. Firstly, very-low-Ti( 5 wt.% constitute less than 10% of the maria. Also, two linear relationships occur between the FeO abundance(FA) and the TiO_2 abundance before and after the threshold, 16 wt.% for FA. Secondly, a new perspective on mare volcanism is derived with the volume FTAs in several important mare basins, although this conclusion should be verified with more sources of data. Thirdly, FTAs in the lunar regolith change with depth to the uppermost surface,and the change is complex over the lunar surface. Finally, the distribution of volume FTAs hints that the highlands crust is probably homogeneous, at least in terms of the microwave thermophysical parameters.