Title: Fold (geology)
Content: active buckling of the layers, whereas similar folds usually form by some form of shear flow where the layers are not mechanically active. Ramsay has proposed a classification scheme for folds that often is used to describe folds in profile based upon curvature of the inner and outer lines of a fold, and the behavior of "dip isogons". that is, lines connecting points of equal dip: (A homocline involves strata dipping in the same direction, though not necessarily any folding.) Folds appear on all scales, in all rock types, at all levels in the crust. They arise from a variety

Title: Fold (geology)
Content: spectrum of metamorphic rocks, and even as primary flow structures in some igneous rocks. A set of folds distributed on a regional scale constitutes a fold belt, a common feature of orogenic zones. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar fault ("fault bend fold"), at the tip of a propagating fault ("fault propagation fold"), by differential compaction or due to the effects of a high-level igneous intrusion e.g. above a laccolith. Folds are classified by their size, fold shape, tightness, and dip of the axial

Title: Anticline
Content: the same direction on both sides of the axial plane. If the angle between the limbs is large (70–120 degrees), then the fold is an "open" fold, but if the angle between the limbs is small (30 degrees or less), then the fold is a "tight" fold. If an anticline plunges (i.e., the anticline crest is inclined to the Earth's surface), it will form "V"s on a geologic map view that point in the direction of plunge. A plunging anticline has a hinge that is not parallel to the earth's surface. All anticlines and synclines have some degree of plunge.

Title: Geology
Content: Movement along faults can result in folding, either because the faults are not planar or because rock layers are dragged along, forming drag folds as slip occurs along the fault. Deeper in the Earth, rocks behave plastically and fold instead of faulting. These folds can either be those where the material in the center of the fold buckles upwards, creating "antiforms", or where it buckles downwards, creating "synforms". If the tops of the rock units within the folds remain pointing upwards, they are called anticlines and synclines, respectively. If some of the units in the fold are facing downward, the

Title: Fold mountains
Content: Fold mountains Fold mountains are mountains that form mainly by the effects of folding on layers within the upper part of the Earth's crust. Before either plate tectonic theory developed, or the internal architecture of thrust belts became well understood, the term was used for most mountain belts, such as the Himalayas. The term is still fairly common in physical geography literature but has otherwise generally fallen out of use except as described below. The forces responsible for formation of fold mountains are called orogenic movements. The term "orogenic" has derived from a Greek word meaning mountain building. These forces

Question: What is the term for a fold of the Earth's crust in which the layers of rock dip inwards?
Answer: Syncline