Global inventory of craters on Mars with alluvial fans and putative deltas (scarp-fronted fans) using CTX data

<p>Dataset ds01 is a delimited text file with the results of our global inventory of craters with alluvial fans and putative deltas (scarp-fronted fans). The dataset contains the following fields from this study along with relevant data from the Robbins & Hynek (2012) crater database and the global geologic map of Mars (Tanaka et al., 2014). </p><p><br></p> <p>Column heading descriptions: </p> <p> </p> <p><br></p><p>CRATER_ID (Robbins and Hynek, 2012): Crater ID is of the format ##-######. The first two numbers indicate the Mars subquad and the last six are craters in order of largest to smallest diameter within that subquad.</p><p> </p><p><br></p><p>LATITUDE_CIRCLE_IMAGE (Robbins and Hynek, 2012): Latitude from the derived center of a nonlinear least squares circle fit to the vertices selected to manually identify the crater rim. Units are decimal degrees North. Column format is variable width, signed decimal to the thousandths place.</p><p> </p><p><br></p><p>LONGITUDE_CIRCLE_IMAGE (Robbins and Hynek, 2012): Longitude from the derived center of a nonlinear least squares circle fit to the vertices selected to manually identify the crater rim. Units are decimal degrees East. Column format is variable-width, signed decimal to the thousandths place.</p><p> </p><p><br></p><p>DIAM_CIRCLE_IMAGE (Robbins and Hynek, 2012): Diameter from a nonlinear least squares circle fit to the vertices selected to manually identify the crater rim. Units are km. Column format is variable-width, decimal to the hundredths place.</p><p> </p><p><br></p><p>DEPTH_RIM_TOPOG (Robbins and Hynek, 2012): Average elevation of each of the manually determined N points along the crater rim. Points are selected as relative topographic highs under the assumption they are the least eroded so most original points along the rim. Units are km. Column format is variable width, signed decimal to the hundredths place.</p><p> </p><p><br></p><p>DEPTH_FLOOR_TOPOG (Robbins and Hynek, 2012): Average elevation of each of the manually determined N points inside the crater floor. Points were chosen as the lowest elevation that did not include visible embedded craters. Units are km. Units are km. Column format is variable-width, signed decimal to the hundredths place.</p><p> </p><p><br></p><p>DEPTH_RIMFLOOR_TOPOG (Robbins and Hynek, 2012): Defined as DEPTH_ RIM_TOPOG - DEPTH_FLOOR_TOPOG Units are km. Column format is variable-width, signed decimal to the hundredths place.</p><p> </p><p><br></p><p>CRATER_NAME (Robbins and Hynek, 2012): Drawn from the USGS’s online Gazetteer of Planetary Nomenclature, maintained by Jennifer Blue (http://planetarynames.wr.usgs.gov/). Column format is variable-width string. Craters that have been named since 2012 may not be included.</p><p> </p><p><br></p><p>FAN_LATITUDE: Latitude (degrees North) of fan apex (defined by the intersection of the fan and catchment). FAN_LATITIDE and FAN_LONGITUDE were collected using Mars 2000 Sphere (radius=3,396,190 m) coordinate system.</p><p> </p><p><br></p><p>FAN_LONGITUDE: Longitude (degrees East) of fan apex (defined by the intersection of the fan and catchment). FAN_LATITIDE and FAN_LONGITUDE were collected using Mars 2000 Sphere (radius=3,396,190 m) coordinate system.</p><p> </p><p><br></p><p>FAN_CLASS: Classification of fan-shaped deposit based on morphology: Alluvial fan, scarp-fronted fan (delta), or equivocal fan (see Section 2 of Wilson et al., GRL for further explanation).</p><p> </p><p><br></p><p>FAN_AZIMUTH_BEARING: The azimuth (relative to zero degrees at North) of each alluvial fan apex (the intersection of the fan and catchment) within its host crater relative to the crater center. For craters with coalesced fans (bajadas) or broad pediments, we identified individual fans by their source basins and apices.</p><p> </p><p><br></p><p>TANAKA_UNIT (Tanaka et al., 2014): Unit name of the geologic unit.</p><p> </p><p><br></p><p>TANAKA_UNIT_DESCRIPTION (Tanaka et al., 2014): Short geologic description of the geologic unit (TANAKA_UNIT).</p><p> </p><p><br></p><p>REFERENCE: The source of the initial identification of the fan feature. Note that many of those marked as “this paper” may have been previously identified by other workers but we identified them independently. Data in this column attempts to capture most publications but it is not intended to be comprehensive. </p><p> </p><p> </p> <p> </p>