Map of ancient tectonic forces on Mars - Visualization of a global stress-field model based on the new geologic map of the Red Planet
ISBN 978-85-88783-11-9
Authors
1Albert, G.; 2Ungvári, Z.; 3Merk, Z.; 4Gede, M.
1EÖTVÖS LORÁND UNIVERSITY Email: albert@ludens.elte.hu
2EÖTVÖS LORÁND UNIVERSITY
3EÖTVÖS LORÁND UNIVERSITY
4EÖTVÖS LORÁND UNIVERSITY
Abstract
In 2014 a new geological map of Mars was published by the USGS (Tanaka et. al 2014). It contains information about the extensional and compressional forces once were active on the planet. This information can be publicly accessed in the geodatabase of the map (i.e. structural lines: wrinkle ridges and grabens). These structures are in geological units mainly from the Noachian and the Hesperian periods (4.1-3.7 and 3.7-3.0 billion years bp. respectively), but a few of them appears in Amazonian units as well (younger than 3.0 billion years). Thus, the force-field which produced these objects vanished long time ago. Despite of this, the analysis and visualization of the stress-tensors may help to fine-tune and understand the global models of the Red Planet. The analysis is based on a projected 2D tensor field which was generated from the lineament pattern. The dynamics (i.e. tension or contraction) of the lines were explained in the original map database (Tanaka et. al 2014). To calculate the tensors, the linear elements were classified according to the dynamical parameters. The polyline sections of the map lineaments were considered vectors (i.e. line sections), and the tensor directions were generated attributes of these vectors. Subsequently, an irregular point cloud of the tensors was generated and processed with a component-wise interpolation. The interpolated values appear on contour/heat and tensor maps, and show the relative stress field of Mars approximately at the end of the Hesperian Period. The generated maps are displayed as overlays on the virtual globe of Google Mars. Reference: Tanaka, K.L., Skinner, J.A., Jr., Dohm, J.M., Irwin, R.P., III, Kolb, E.J., Fortezzo, C.M., Platz, T., Michael, G.G., and Hare, T.M., 2014, Geologic map of Mars: U.S. Geological Survey Scientific Investigations Map 3292, scale 1:20,000,000, pamphlet 43 p., http://dx.doi.org/10.3133/sim3292.
Keywords
Mars geology; tectonic map; virtual globe