Martian intracrater splotches: Occurrence, morphology, and colors

Abstract Martian intracrater splotches and related streaks are studied with global data on their occurrence and regional data on color and morphology. The fraction of craters with splotches is greatest at high latitudes. Splotch occurrence is not strongly correlated with surface properties such as albedo and thermal inertia except where these correlate with substantial sediment cover. Large numbers of splotches are or include dunes, especially at high southern latitudes. Color data show that the dune and nondune materials in splotches are part of one related group of materials that may be of similar composition but varying particle sizes. The color data also show that some streaks are simply material deflated from splotches and mixed with local plains material while other streaks are more complex and may involve erosion of thin surface layers by material blown from the splotches. Splotches appear to be trapped eolian sand but probably have been formed by a great variety of mechanisms. A large percentage of craters with splotches show evidence of complex histories of sediment deposition and erosion. Many splotches may be lag deposits from erosion of regional sediment cover. Present sediment budgets in splotches are not known, but there is some evidence for loss of material and no evidence for resupply from outside the craters.

[1]  P. Gierasch,et al.  A model of Martian slope winds - Implications for eolian transport , 1982 .

[2]  R. Arvidson.  Wind-blown streaks, splotches, and associated craters on Mars: Statistical analysis of Mariner 9 photographs , 1974 .

[3]  Steven W. Lee.  Mars - Wind streak production as related to obstacle type and size , 1984 .

[4]  S. Morse.  Adcumulus Growth of Anorthosite at the Base of the Lunar Crust , 1982 .

[5]  M. Carr,et al.  Martian channels and valleys: Their characteristics, distribution, and age , 1981 .

[6]  John F. McCauley,et al.  Morphology and distribution of common ‘sand’ dunes on Mars: Comparison with the Earth , 1979 .

[7]  R. Hosker,et al.  Diffusion-deposition patterns in Martian streaks , 1978 .

[8]  E. Eliason,et al.  Global color variations on the Martian surface , 1978 .

[9]  David L. Evans,et al.  Mars: Definition and Characterization of Global Surface Units, with Compositional Emphasis. , 1979 .

[10]  P. Gierasch,et al.  Wind streaks on Mars: Meteorological control of occurence and mode of formation , 1981 .

[11]  Farouk El-Baz,et al.  Eolian features in the western desert of Egypt and some applications to Mars , 1979 .

[12]  E. Miner,et al.  Time variability of Martian bolometric albedo , 1981 .

[13]  T. Thorpe.  Viking Orbiter photometric observations of the Mars phase function July through November 1976 , 1977 .

[14]  Classification of surface units in the equatorial region of Mars based on Viking Orbiter color, albedo, and thermal data , 1982 .

[15]  P. Thomas,et al.  North-south asymmetry of eolian features in Martian polar regions - Analysis based on crater-related wind markers , 1981 .

[16]  Ronald Greeley,et al.  Rate of wind abrasion on Mars , 1982 .

[17]  P. Thomas.  Present wind activity on Mars: Relation to large latitudinally zoned sediment deposits , 1982 .

[18]  P. Christensen,et al.  Martian dust mantling and surface composition: Interpretation of thermophysical properties , 1982 .

[19]  J. Veverka,et al.  Classification of wind streaks on Mars , 1981 .

[20]  Joshua Lederberg,et al.  Variable features on Mars 2: Mariner 9 global results , 1973 .

[21]  J. Burns,et al.  The astronomical theory of climatic change on Mars , 1980 .

[22]  V. Woerkom.  The Astronomical Theory of Climate Changes , 1953 .

[23]  P. Christensen.  Eolian intracrater deposits on Mars: Physical properties and global distribution , 1983 .

[24]  W. Ward.  Climatic variations on Mars: 1. Astronomical theory of insolation , 1974 .

[25]  J. Pollack,et al.  Properties and effects of dust particles suspended in the Martian atmosphere , 1979 .

[26]  L. Soderblom,et al.  Mars' global properties: maps and applications. , 1982 .

[27]  R. Arvidson,et al.  Differential aeolian redistribution rates on Mars , 1979, Nature.

[28]  J. Veverka,et al.  Seasonal and secular variation of wind streaks on Mars - An analysis of Mariner 9 and Viking data , 1979 .

[29]  Joshua Lederberg,et al.  Variable features on Mars: Preliminary mariner 9 television results , 1972 .

[30]  K P Klaasen,et al.  Inflight performance of the Viking visual imaging subsystem. , 1977, Applied optics.

[31]  A. Peterfreund.  Visual and infrared observations of wind streaks on Mars , 1981 .

[32]  F. Palluconi,et al.  Thermal inertia mapping of Mars from 60°S to 60°N , 1981 .