On January 26, 2001, the Kachchh region in western India
suffered the most deadly earthquake in Indias history. This shaded topography
view of landforms northeast of the city of Bhuj depicts geologic structures
that are of interest in the study the tectonic processes that may have led to
that earthquake. However, preliminary field studies indicate that these
structures are composed of Mesozoic rocks that are overlain by younger rocks
showing little deformation. Thus these structures may be old, not actively
growing, and not directly related to the recent earthquake.
The Haro Hills are on the left and the Kas Hills are on the right. The Haro
Hills are an anticline, which is an upwardly convex elongated fold of layered
rocks. In this view, the anticline is distinctly ringed by an erosion resistant
layer of sandstone. The east-west orientation of the anticline may relate to
the crustal compression that has occurred during Indias northward movement
toward, and collision with, Asia. In contrast, the largest of the Kas Hills
appears to be a tilted (to the south) and faulted (on the north) block of
layered rocks. Also seen here, the linear feature trending toward the southwest
from the image center is an erosion-resistant dike, which is an igneous
intrusion into older host rocks along a fault plane or other crack. These
features are simple examples of how shaded topography can provide a direct
input to geologic studies.
In this image, colors show the elevation as measured by the Shuttle Radar
Topography Mission (SRTM). Colors range from green at the lowest elevations,
through yellow and red, to purple at the highest elevations. Elevations here
range from near sea level to about 300 meters (about 1000 feet). Shading has
been added, with illumination from the north (image top).
Elevation data used in this image was acquired by the Shuttle Radar Topography
Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM
used the same radar instrument that comprised the Spaceborne Imaging
Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the
Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional
measurements of the Earths surface. To collect the 3-D data, engineers added a
60-meter-long (200-foot) mast, installed additional C-band and X-band antennas,
and improved tracking and navigation devices.
Size: 26.3 x 16.6 kilometers (16.3 x 10.3 miles)
Location: 23.4 deg. North lat., 69.8 deg. East lon.
Orientation: North toward the top
Date Acquired: February 2000