This indicates the first sign of this type of surface-shifting geological activity on a world other than Earth. However, they could not find areas where the old crust was destroyed to make room for the new. Surface blocks are known to have shifted in the same way blocks of Earth's outer ground layer on either side of the San Andreas fault move past each in California.
Forces acting to pull the lunar crust apart formed the Virtanen graben, informally named for a nearby crater. These graben are located on a rise with several hundred meters of relief revealed in topography derived from Lunar Reconnaissance Orbiter Camera.
These new findings raise questions about how the moon formed and evolved, researchers said. Now, images collected by the Lunar Reconnaissance Orbiter hints the moon has probably seen tectonic activity within the last 50 million years.
In these photos, researchers spotted a dozen or so narrow, trenchlike features known as graben in the lunar highlands and in the dark plains of volcanic rock known as the mare basalts.
Graben are essentially troughs with two faults or cracks in the surface on either side of them. They are thought to have formed as the lunar crust was stretched. The graben the scientists detected, which reach up to about 1, feet meters wide and 1.
This suggests they formed recently — otherwise, they would be marred more often by craters from meteor impacts over time. Locations of newly discovered young graben red stars — trenchlike scars — on the moon along with recently detected white dots and previously known black dots contractional lobate scarps.
The newfound graben are widely distributed and located near lobate scarps. The locations of 26 shallow moonquakes recorded by the Apollo seismic network with stations at the Apollo 12, 14, 15, and 16 landing sites are shown by the black triangles.
However, if this was true, such compression would have suppressed the creation of graben — these ditches typically form when the crust stretches, not crinkles. Instead, these findings suggest the moon was not completely molten after it was formed. If this were the case, the moon would not contract strongly enough to suppress the emergence of graben.
A series of graben in a patch of mare basalts that occupy a valley south of Mare Humorum cut across and deformed several small diameter impact craters. The walls and floors of the graben crosscut a degraded 27 m diameter crater inset, upper white arrow and a 7 m diameter crater inset, lower white arrow.
Since small craters only have a limited lifetime before they are destroyed by other impacts, their deformation by graben indicates that these fault-bound troughs are relatively young. He and his colleagues detailed their findings online Feb.Geologic Activity. Lava River. A recent example of these on-going forces was the Mount Borah earthquake.
During that event the highest point in Idaho, Mount Borah, got a bit higher when a magnitude earthquake occurred across the base of the Lost River Range. Craters of the Moon National Monument and Preserve P.O.
Box 29 Arco. Sep 22, · The Passive Seismic Experiment was the first seismometer placed on the Moon’s surface. It detected lunar "moonquakes" and provided information about the internal structure of the Moon. This experiment studied the propagation of seismic waves through the Moon and provided the first detailed look at.
Earth's Moon appears seismically quiet: its major volcanic and tectonic activity is confined to its distant past, as evidenced by the lack of new large-scale features on the surface. However, recent images from the Lunar Reconnaissance Orbiter (LRO) have revealed smaller features that had escaped earlier notice.
More Evidence That The Moon Contributes To Earthquakes.
Not all large earthquakes are caused by the moon’s movements. But some of them might be, and so we’d do well to pay closer attention. Scientists find deeper meaning for Moon rumblings -- (NY Times) more information about deep rather than shallow moonquakes.
New computers uncover old quakes on the Moon -- (Discover Magazine) Mr. Moonquake -- Yosio Nakamura, a colleague of Neal, is a leading authority on moonquakes. At present all evidence points to the Moon as a body in which, given its small size, all heat-driven internal processes have run down.
Seismic activity is probably far less than that of Earth, though this conclusion needs to be verified by longer-running observations than Apollo provided.