The origin of selected lunar geochemical anomalies: Implications for early volcanism and the formation of light plains
The origin of selected lunar geochemical anomalies: Implications for early volcanism and the formation of light plains
复制标题
选定的月球地球化学异常的起源：对早期火山活动和光平原形成的影响
DOI：
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发表时间：
1985
期刊：
影响因子：
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通讯作者：
P. Clark
中科院分区：
文献类型：
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作者：
B. Hawke;P. Spudis;P. Clark
阿波罗轨道地球化学、光地质学和其他遥感数据集被用来识别和描述月球东侧和远侧的地球化学异常，并调查其形成过程。异常位于以下区域：(1)巴尔默盆地，(2)Mare Smythii东北地形，(3)朗格马克陨石坑附近，(4)巴斯德陨石坑，(5)Milne盆地西北部，(6)门捷列夫盆地东北部，(7)科罗廖夫盆地北部和东北部，(8)Tarunus陨石坑以北，(9)Orientale盆地以北。这些异常通常与英布里亚或死神时代的轻平原单元有关，这些单元显示出暗晕的撞击坑。最近对暗晕陨石坑的光谱反射率研究的结果加上对异常表面化学的考虑有力地表明，与显示暗晕陨石坑的浅平原沉积物有关的那些地球化学异常是由于玄武岩单元的存在，这些玄武岩单元要么被不同厚度的高地碎片覆盖，要么表面被大量的高地物质污染。古代火山表面被不同数量的高地物质掩埋或污染，似乎是形成月球光平原的一个重要(尽管不是主要的)过程。月球东部和背面的玄武岩火山活动在空间和时间上都比人们所接受的要广泛得多。
The Apollo orbital geochemistry, photogeologic, and other remote sensing data sets were used to identify and characterize geochemical anomalies on the eastern limb and farside of the Moon and to investigate the processes responsible for their formation. The anomalies are located in the following regions: (1) Balmer basin, (2) terrain northeast of Mare Smythii, (3) near Langemak crater, (4) Pasteur crater, (5) terrain northwest of Milne basin, (6) northeast of Mendeleev basin, (7) north and northeast of Korolev basin, (8) terrain north of Taruntius crater, and (9) terrain north of Orientale basin. The anomalies are commonly associated with Imbrian- or Nectarian-aged light plains units which exhibit dark-haloed impact craters. The results of recent spectral reflectance studies of dark-haloed impact craters plus consideration of the surface chemistry of the anomalies strongly indicate that those geochemical anomalies associated with light plains deposits which display dark-haloed impact craters result from the presence of basaltic units that are either covered by varying thickness of highland debris or have a surface contaminated with significant amounts of highlands material. The burial or contamination of ancient volcanic surfaces by varying amounts of highland material appears to have been an important (though not the dominant) process in the formation of lunar light plains. Basaltic volcanism on the eastern limb and farside of the Moon was more extensive in both space and time than has been accepted.