Lunar landforms are the results of geological and geomorphic processes on the lunar surface.It is very important to identify the types of lunar landforms.Geomorphology is the scientific study of the origin and evoluti...Lunar landforms are the results of geological and geomorphic processes on the lunar surface.It is very important to identify the types of lunar landforms.Geomorphology is the scientific study of the origin and evolution of morphological landforms on planetary surfaces.Elevation and relief amplitude are the most commonly used geomorphic indices in geomorphological classification studies.Previous studies have determined the elevation classification criteria of the lunar surface.In this paper,we focus on the classification criteria of the topographic relief amplitude of the lunar surface.To estimate the optimal window for calculating the relief amplitude of the lunar surface,we use the mean change-point method based on LOLA(Lunar Orbiter Laser Altimeter)Digital Elevation Model(DEM)data and SLDEM2015 DEM data combining observations from LOLA and SELenological and Engineering Explorer Terrain Camera(SELENE TC).The classification criterion of the lunar surface relief amplitude is then determined according to the statistical analysis of basic lunar landforms.Taking the topographic relief amplitudes of 100 m,200 m,300 m,700 m,1500 m and 2500 m as thresholds,the lunar surface is divided into seven geomorphic types,including minor microrelief plains(<100 m),minor microrelief platforms[100 m,200 m),microrelief landforms[200 m,300 m),small relief landforms[300 m,700 m),medium relief landforms[700 m,1500 m),large relief landforms[1500 m,2500 m)and extremely large relief landforms(≥2500 m).The minor microrelief plains are mainly distributed in the maria and the basalt filled floors of craters and basins,while the minor microrelief platforms are mainly in the transition regions between the maria and highlands.The microrelief landforms are mainly located in regions with relatively high topography,such as wrinkle ridges and sinuous rilles in the mare.The small relief landforms are mainly scattered in the central peak and floor fractures of craters.The medium relief landforms are mainly distributed in the transition regions betw展开更多
Based on an analysis of full-cover multi-beam bathymetric data,seismic and sub-bottom profiling data,and other geological-geophysical data sets,the geomorphologic features of the Ryukyu trench-arc-backarc(T-A-BA)syste...Based on an analysis of full-cover multi-beam bathymetric data,seismic and sub-bottom profiling data,and other geological-geophysical data sets,the geomorphologic features of the Ryukyu trench-arc-backarc(T-A-BA)system are delineated,and a geomorphologic map of the system is compiled.The re-sults show that the evolution and spatial distribution patterns of the geomorphologic types of the Ryukyu T-A-BA system are controlled mainly by tectonic move-ments.The tectonic geomorphologic characteristics of the Ryukyu Arc(RA) differ distinctly from those of the East China Sea(ECS) continental shelf and slope.In term of geological structures,RA consists of the Tokara volcanic ridge,the Ryukyu folded ridge,the fore-arc accre-tion-wedge ridge and the Amami Depression and the fore-arc depressions between the ridges,which is com-posed of a complex of alternating island-slope ridges and fault basins.The slope of the ECS is a passive continental margin with stepwise faults.The Okinawa Trough (OT)is a backarc rift in which tectonic movements are inten-sive,with active volcanic and hydrothermjal eruptions and sea floor spreading.The development of geomorphic features of the OT is controlled by the central en echelon spreading axes,the faults along the ECS slope and the marginal faults to the west of the Tokara vol-canic ridge.The geomorphic complex of the OT is ar-ranged in the following pattern:the en echelon grabens and volcanic chains formed by rifting and spreading lie in the central part of the trough,the turbidite plains inclining eastwards-southeastwards from the slope foot of the ECS lie in the western-northwestern parts of the OT,and the volcaniclastic deposit plains inclining westward-northwestwards from the western slope foot of the RA lie in the eastern-southeastern parts of the OT. In term of tectonic geomorphology,the OT forms a natural division between the shelf of the ECS and the RA.展开更多
基金Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDB41000000National Natural Science Foundation of China,No.42130110,No.41571388Key Project of National Basic Work of Science and Technology,No.2015FY210500。
文摘Lunar landforms are the results of geological and geomorphic processes on the lunar surface.It is very important to identify the types of lunar landforms.Geomorphology is the scientific study of the origin and evolution of morphological landforms on planetary surfaces.Elevation and relief amplitude are the most commonly used geomorphic indices in geomorphological classification studies.Previous studies have determined the elevation classification criteria of the lunar surface.In this paper,we focus on the classification criteria of the topographic relief amplitude of the lunar surface.To estimate the optimal window for calculating the relief amplitude of the lunar surface,we use the mean change-point method based on LOLA(Lunar Orbiter Laser Altimeter)Digital Elevation Model(DEM)data and SLDEM2015 DEM data combining observations from LOLA and SELenological and Engineering Explorer Terrain Camera(SELENE TC).The classification criterion of the lunar surface relief amplitude is then determined according to the statistical analysis of basic lunar landforms.Taking the topographic relief amplitudes of 100 m,200 m,300 m,700 m,1500 m and 2500 m as thresholds,the lunar surface is divided into seven geomorphic types,including minor microrelief plains(<100 m),minor microrelief platforms[100 m,200 m),microrelief landforms[200 m,300 m),small relief landforms[300 m,700 m),medium relief landforms[700 m,1500 m),large relief landforms[1500 m,2500 m)and extremely large relief landforms(≥2500 m).The minor microrelief plains are mainly distributed in the maria and the basalt filled floors of craters and basins,while the minor microrelief platforms are mainly in the transition regions between the maria and highlands.The microrelief landforms are mainly located in regions with relatively high topography,such as wrinkle ridges and sinuous rilles in the mare.The small relief landforms are mainly scattered in the central peak and floor fractures of craters.The medium relief landforms are mainly distributed in the transition regions betw
文摘Based on an analysis of full-cover multi-beam bathymetric data,seismic and sub-bottom profiling data,and other geological-geophysical data sets,the geomorphologic features of the Ryukyu trench-arc-backarc(T-A-BA)system are delineated,and a geomorphologic map of the system is compiled.The re-sults show that the evolution and spatial distribution patterns of the geomorphologic types of the Ryukyu T-A-BA system are controlled mainly by tectonic move-ments.The tectonic geomorphologic characteristics of the Ryukyu Arc(RA) differ distinctly from those of the East China Sea(ECS) continental shelf and slope.In term of geological structures,RA consists of the Tokara volcanic ridge,the Ryukyu folded ridge,the fore-arc accre-tion-wedge ridge and the Amami Depression and the fore-arc depressions between the ridges,which is com-posed of a complex of alternating island-slope ridges and fault basins.The slope of the ECS is a passive continental margin with stepwise faults.The Okinawa Trough (OT)is a backarc rift in which tectonic movements are inten-sive,with active volcanic and hydrothermjal eruptions and sea floor spreading.The development of geomorphic features of the OT is controlled by the central en echelon spreading axes,the faults along the ECS slope and the marginal faults to the west of the Tokara vol-canic ridge.The geomorphic complex of the OT is ar-ranged in the following pattern:the en echelon grabens and volcanic chains formed by rifting and spreading lie in the central part of the trough,the turbidite plains inclining eastwards-southeastwards from the slope foot of the ECS lie in the western-northwestern parts of the OT,and the volcaniclastic deposit plains inclining westward-northwestwards from the western slope foot of the RA lie in the eastern-southeastern parts of the OT. In term of tectonic geomorphology,the OT forms a natural division between the shelf of the ECS and the RA.