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| Triple junctions of wrinkle ridges at the western edge of Bolyai crater floor. Image field of view is 1270 meters, LROC Narrow Angle Camera (NAC) observation M134368363L, LRO orbit 4935, July 21, 2010; incidence angle 72.2° at 1.27 meters resolution from 61.04 kilometers. Sunlight is from the west. View the larger (~80%) original LROC Featured Image HERE [NASA/GSFC/Arizona State University]. |
LROC News System
Today's Featured Image involves sinuous ridges observed at the western edge of the mare basalt deposit on the floor of Bolyai crater. Bolyai is a ~100 km diameter crater located at 33.85°S, 126.12°E, about 400 km south of Tsiolkovskiy crater. The northern part of the crater floor is filled by a mare basalt deposit (see WAC context image at the bottom of this post). Notice that the sunlight is from the left side of the image, thus the circular features (craters) are negative relief and sinuous line-features are positive relief.
The ridges show bifurcations at the middle of the image, and two ridge branches extending toward the northeast and southeast of this image gradually become less apparent. The southwestern branch strongly meanders and eventually disappears as well. On the other hand, the northwestern branch extends on the crater slopes all the way along the western boundary of the mare deposit (see the NAC context image below), about 80 to 300 m away from this "shoreline". How did all these ridge systems form? Could they really be "splash marks" like in Tuesday's post, or are they something else?
In many cases, splash marks include boulders that were deposited at the "wave front" of the melt, which is not the case in today's image. The wrinkle ridges, a compressional deformation feature caused by thrust faults, can crosscut each other, which would explain the bifurcation of the ridges in the top image. But then, did the whole western part of the lava pond slip, forming the surrounding wrinkle ridges? Obviously, a series of complicated geologic events happened in this particular mare deposit within Bolyai.
Explore this set of sinuous ridges full LROC NAC frame for yourself, HERE.
Related Posts:
Constellation Region of Interest at Mare Tranquillitatis
Wrinkle ridge in Oceanus Procellarum
Stress and pull
Tectonics in Mare Frigoris
Bulging Wrinkle
The ridges show bifurcations at the middle of the image, and two ridge branches extending toward the northeast and southeast of this image gradually become less apparent. The southwestern branch strongly meanders and eventually disappears as well. On the other hand, the northwestern branch extends on the crater slopes all the way along the western boundary of the mare deposit (see the NAC context image below), about 80 to 300 m away from this "shoreline". How did all these ridge systems form? Could they really be "splash marks" like in Tuesday's post, or are they something else?
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| Western edge of mare basalt deposits, traced by wrinkle ridges on the slopes of Bolyai crater wall. A section of the width of LROC NAC frame M134368363L is layered on the Google Earth lunar digital terrain model. Section field of view is approximately 2.4 km across, and the area in the Featured Image is outlined by the white box [NASA/GSFC/JAXA/USGS/ASU]. |
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| Northern part of Bolyai crater, once again in Google Moon, and as the scene might be viewed from 47 km over a point southeast of the area of interest. LROC Wide Angle Camera (WAC) monochrome (604nm) mosaic stitched from observations gathered during 9 sequential orbital opportunities averaging 46.8 km, and at 62 meters resolution, November 25, 2011. The locations of the full NAC frame M134368363L is outlined by the blue rectangle and the yellow arrow marks the approximate location of the field of view highlighted in the LROC Featured Image released August 2, 2012 [NASA/GSFC/Arizona State University]. |
Explore this set of sinuous ridges full LROC NAC frame for yourself, HERE.
Related Posts:
Constellation Region of Interest at Mare Tranquillitatis
Wrinkle ridge in Oceanus Procellarum
Stress and pull
Tectonics in Mare Frigoris
Bulging Wrinkle
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