Tectonic Style And Formation Process Of Mare Ridge Of Copernicus In Mare Imbrium Region

Mare ridge is a kind of linear structure which distributed most widely in the mare onthe moon surface. Although the topographic characteristics of it have been wellrecognized, its mechanism and process of evolution have been contesting. It has beenfound that the lobate scarp which is another kind of linear structure formatting inCopernicus which is the newest lunar geological history period. This changed theconcept that the moon has no tectonic activity since the3.1billion years, butformation of the times of mare ridges is unclear. Thus, the study of causes of processand the formation of the times of mare ridges is the key to recognize the structureformation mechanism and evolution process in lunar surface. This paper is based onthe data of American Orbiter(LRO). Mare ridges in Mare Imbrium are interpreted. Itconfirmed by the diameter and morphology of small craters relative dating methodand the cross-cut relationship of mare ridges and small impact craters that some mareridges began to develop in Copernicus, further demonstrating there still is tectonicmovement on the moon surface. Physical modeling experiments are designed forsimulating mare ridge in basal contraction mechanism and simulated with differentparameters. The top surface, the profile shape, as well as structural features of thesimulation results are comparative analyzed with the actual mare ridges. The resultsshow that basal contraction may be the mechanism of the mare ridges whichdeveloped in Copernicus. In addition, it is found that the mare ridges are evolved bythe lobate scarps in this mechanism, and there are new lobate scarps formatting aftermare ridges developed. Through the monitoring of the experiment and estimates ofthe data, the mare ridge evolutionary process contains the plastic deformation period,the lobate scarps development period, mare ridge formation period and lobate scarpsre-development period. Mare ridges and lobates scarps are not two kinds of linearstructures which completely independent developed limited by materials andenvironments.