Amazing stuff!
"A new study suggests that, beneath its cold and dormant exterior, the moon is more dynamic than previously thought.
“Knowing that the moon is still geologically dynamic has very real implications for where we’re planning to put our astronauts, equipment and infrastructure on the moon,” says Jaclyn Clark, an assistant research scientist at the University of Maryland in the US.
Scientists have been examining the moon’s surface in detail for decades. Evidence from dark, flat areas filled with solidified lava called lunar maria has previously revealed that the moon’s surface experienced significant compression in its distant past. Large, arching ridges on the surface were caused by contractions billions of years ago. ...
A study ... suggests that, beneath the surface, the moon might still be quite active.
The ridges on the far side of the moon are notably younger than those on its near side, the researchers found. This suggests subsurface dynamics much more recently than expected. ..."
From the abstract:
"The timing and scale of lunar tectonism provide a crucial insight into the geologic evolution of Earth's Moon. Within the nearside lunar maria, wrinkle ridges formed during and after the emplacement of the mare basalts as a result of subsidence-induced contraction. Past analyses of lunar wrinkle ridges and associated fault structures have helped to constrain lunar tectonic and thermal history. However, contractional tectonics in the lunar maria may not be limited to the formation of large-scale structures in the distant geologic past.
In contrast to larger, subsidence-induced lunar wrinkle ridges, recent investigations have identified contractional structures within the nearside lunar maria that are dimensionally small and recently formed via a combination of global stresses.
The identification of those small mare ridges (SMRs) demonstrated that the lunar nearside maria are subject to compressional stresses that are recently and potentially currently active, but the presence of such features in the lunar farside maria was never investigated.
Furthermore, the exact timing of SMR formation and the geometry of the associated fault structures remain poorly constrained.
Here, we present the first observations of widespread SMRs in the lunar farside maria and South Pole–Aitken Basin. We also derive absolute model age estimates for SMR formation, and we constrain SMR-forming fault geometries via elastic dislocation modeling. Our analysis provides the first globally complete perspective of recent lunar tectonics, and we show that lunar fault structures may be recently and potentially currently active within regions of interest for upcoming lunar missions."
Figure 1. (A) Distribution of farside SMRs (yellow polylines) relative to lunar maria (red polygons) and overlaid onto an LROC Wide Angle Camera global mosaic centered at a 180° meridian. (B) Small-scale image (LROC NAC M1392716156LE) of the SPA SMR cluster showing individual ridge segments (white arrows). (C) Farside SMR cluster directional means (orange lines) overlaid onto the predicted feature orientations that would result from the combination of global contraction, orbital recession, and solid body tides
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