A study of a possible lunar batholith

The author suggests that a particular foothills feature located northwest of, but nearly parallel to, the Apennine Mountains of the moon is a batholith which was generated deep beneath the Apennines as a result of the Imbrium impact. Confirmation of this theory depends upon whether batholiths can be generated on the moon. The Apollo 11 rock samples apparently originated by a small degree of partial melting at depths between 200 and 600 km. The lava produced by the melt was chemically different from the anorthositic highlands. Once the lunar crust had congealed, any magmatic flow from the interior would find movement toward the surface increasingly hampered by the continually thickening and hardening crust. Though faulting caused by meteorite impact would result in easier access locally through the crust by the migrating magma, that access would be blocked off once the lava reached the surface and congealed over the fault. It is suggested that the lava collected in a series of secondary magma chambers located closer and closer to the surface. As the continuing lava stream fed the original secondary chamber, pressure build-up on the roof caused brecciation and cracking. The stream then migrated through the new cracks upward to a point where it could not proceed further, so that another secondary chamber was established. This process continued until the lava reached the surface or until the radioactive heat source cooled.