Scientists have studied the moon's surface for decades to help piece together its complex geological and evolutionary history. Evidence from the lunar maria (dark, flat areas on the moon filled with solidified lava) suggested that the moon experienced significant compression in its distant past. Researchers suspected that large, arching ridges on the moon's near side were formed by contractions that occurred billions of years ago—concluding that the moon's maria has remained dormant ever since.
What an exciting study. The TL;DR:
GEOlogy is the study of the earth and how it changes over time. At a high level the Earth is sustained by the geodynamo - electromagnetic fluid movement in the core and mantle that sustains mantle convection and plate tectonics. The Moon doesn’t have any of that, so geological processes on the Moon is of intense study. In this paper they found pretty good evidence of contractional tectonics - the surface wrinkling from the Moon shrinking and changes in orbit - effecting all sides of the Moon in the form of scarps which induce moonquakes. This has implications for mapping the surface for future exploratory missions and long-term habitation (don’t want to have a colony in a seismically unstable place).