[3] The Compton–Belkovich Thorium Anomaly was found in 1998 by the Gamma Ray Spectrometer (GRS) instrument on board the Lunar Prospector (LP) and subsequently identified as a hotspot, located around 61°06′N 99°30′E / 61.1°N 99.5°E / 61.1; 99.5.

[5] High resolution images from the Lunar Reconnaissance Orbiter LRO made it possible to analyze the surface features of the Compton–Belkovich Thorium Anomaly in 2011.

[9] A direct analysis of Apollo program samples revealed that most lunar volcanism occurred around 3 to 4 billion years ago.

However, volcanic activity on the unsampled lunar back side could have occurred around 1 billion years ago.

[10] As the lava cooled, it would have crystallized to produce a silicate structure; incompatible elements such as thorium would have been excluded from the process and formed thorium-rich pockets in the remaining liquid rock.

[5][11] The eruption associated with the thorium anomaly could have created the elevated features to the west and the low and broad area to the east.

[12] The latest possible eruptions of lava would have made domes with steeper slopes, and also would have caused small bulges, as they would barely reach the surface.