Morphology and Morphometry of Double Layered Ejecta Craters on Mars

Double layered ejecta (DLE) craters display two distinct layers of ejecta that appear to have been emplaced as a mobile, ground-hugging flow. While volatile content within the target, atmosphere, or some combination of the two is generally considered a major variable enhancing the mobility of ejecta, the presence of unconsolidated surface materials may also have some effect. This statement is studied further here, aiming to determine whether bulk target lithology and/or attributes of the surface have any effect on morphometric properties between DLEs situated on sedimentary targets to those on volcanic ones. Results suggest that ejecta mobility (the distance ejecta travels from the crater rim) generally increases with increasing latitude and may reflect volatile concentrations on Mars, while lobateness (sinuosity of the perimeter of ejecta) generally decreases with increasing latitude. Furthermore, DLEs on sedimentary targets appear to have a higher EM, on average, than those on volcanic targets

MU-3 Stream Surveys \u2013 Mussels

EO4152This report summarizes the freshwater mussel survey results from 12 western Pennsylvania streams. Over 12,600 mussels were observed representing 28 species. Data and analyses collected for these surveys now represents the best available scientific data in these stream reaches