Geography Topics

The Lehman discontinuity separates the solid inner core from the liquid outer core. The Gutenberg discontinuity separates the mantle from the core, while the Mohorovicic separates the crust from the mantle.

Convective removal or delamination of the dense lithospheric root replaces cold lithosphere with hot, buoyant asthenosphere, causing rapid regional isostatic uplift without horizontal crustal shortening.

Walther's Law states that a vertical sequence of facies reflects environments that were originally laterally adjacent, provided the sequence contains no major depositional unconformities.

Mogotes are steep-sided, isolated limestone towers that rise from flat alluvial plains in deep tropical karst landscapes. Uvalas and poljes are larger erosional depression complexes.

The uppermost layer of a glacier behaves as a brittle solid under low hydrostatic pressure, forming crevasses. Below 30-40 meters, high pressure induces plastic deformation, closing fractures.

An accretionary prism or accretionary wedge is a mass of deformed sedimentary and volcanic rock scraped off the subducting plate onto the overriding plate.

A fault-line scarp is formed by differential erosion along an old fault line where tectonic activity has ceased, as opposed to an active fault scarp directly exposing the slip plane.

Granular disintegration occurs when different minerals expand and contract at different rates due to temperature swings, shattering the rock into individual grains.

Trellis drainage patterns feature primary parallel valleys aligned with structural folds, where tributaries intersect the main stream channels at nearly 90-degree angles.

The old-age stage of W.M. Davis's cycle is characterized by the formation of a peneplain, which is a low-relief rolling plain containing isolated residual hills called monadnocks.