GENERAL GEOLOGY

Detailed explanation-1: -Sills are horizontal igneous rocks that were formed by igneous intrusions that flowed horizontally through existing rock. Laccoliths are larger sill-like igneous intrusions, but are arched upward.

Detailed explanation-2: -laccolith, in geology, any of a type of igneous intrusion that has split apart two strata, resulting in a domelike structure; the floor of the structure is usually horizontal.

Detailed explanation-3: -A laccolith is a dome shaped intrusive body that has intruded between layers of sedimentary rock. The rising magma forces the overlying layers to rise up into a dome. A sill is similar to a dike with the exception that sills run parallel to the existing rock bed instead of cutting through it.

Detailed explanation-4: -A dike could be horizontal and a sill could be vertical-it all depends on the orientation of features in the surrounding rocks. A laccolith is a sill-like body that has expanded upward by deforming the overlying rock. If a sill forms, but magma pools and sags downward, it creates a lopolith.