Mars Viking Geologic Map I-2087 of West Mangala Valley
The west Mangala Valles area merits detailed geologic study because it contains several small channels whose ages can be determined relative to geologic units that range in age from early (Noachian) to late (Amazonian) periods of Martian history. Because the small channels are of three ages and channels of each age are of a geomorphic type unique to that age, their study increases our understanding of the continuity of fluvial processes in the evolutionary history of Mars. For these reasons, part of the area is a proposed site for a sample-return mission to Mars.
- Mimetype
- application/zip
- Filename
- Mars-Viking-Geologic-Map-I-2087-of-West-Mangala-Valley.zip
- Publisher
- USGS Astrogeology Science Center
- Author
- Mary G. Chapman, Harold Masursky, and Arthur L. Dial Jr.
- Originator
- USGS Astrogeology Science Center
- Group
- MRCTR
- Added to Astropedia
- 27 September 2013
- Modified
- 16 June 2021
General
- Purpose
Mars geological mapping
- Geospatial Data Presentation Form
- Geologic Map, Vector Data, Raster Data
- Series Id
- I-2087
- Edition
- 1
Keywords
- Target
- Mars
- Search Terms
- Mars, Geology, West Mangala Valley
Contact and Distribution
- Access Constraints
- none
- Use Constraints
- none
Data Status and Quality
- Process Description
The map base is a composite of parts of two Viking 1:500, 000-scale photomosaics (U.S. Geological Survey, 1985). These photomosaics are based on high-resolution images except in the area hat now forms the northwest corner of the composite, for which only lower resolution images are available. Because the latter images were acquired at sun angles opposite these on the high-resolution images, the "mesa" that appears in this area is actually a depression. Some map units correspond or are partly equivalent to units on smaller scale maps (Mutch and Morris, 1979, Scott and Tanaka, 1986). However, in many places interpretations and contacts have been revised to reflect information visible on high-resolution Viking images, geomorphic details on these images were clarified by spatial filtering (Condit and Chavez, 1979). The depths of channels, thicknesses of geologic units, and heights of scarps were obtained in places using photoclinometric methods of Davis and Scott (1984). The relative ages of geologic units and geomorphic features such as small channels and faults were established by stratigraphic relations and supported by crater counts.
Geospatial Information
- Quad Name