Key points are not available for this paper at this time.
The martian tropical water ice spatial and temporal distribution was characterized using impact crater ejecta type, location, size, and age in one of two epochs, 3.4 Ga, using statistical models designed for spatial and temporal correlation structures. The indicator thought to identify the presence of ice is craters with layered ejecta, while the indicator thought to identify no ice is craters with radial ejecta. These indicators imply the location (longitude and latitude) and, potentially, depth (crater diameter as a proxy) of ice, and when the ice was present. The spatial and temporal distribution of layered ejecta versus radial ejecta may inform on the geography and evolution of ice. A statistical spatial point analysis was conducted on a 54-sample data set (craters with diameters 2.77 km to 10.00 km) for an equatorial region (0o to -30o S, and 10o E to 340o W. The analysis shows there is insufficient evidence to support a non-random spatial and temporal distribution of tropical ice.
Riggs et al. (Wed,) studied this question.