What is a fan fold in geography?

Fan Fold: This is a system of folds consisting of anticlines and synclines but with limbs having contrasting features. In this case the limbs of anticlines dip towards each other and the limbs of synclines dip away from each other.

What is symmetrical fold?

A symmetrical fold is one in which the axial plane is vertical. An asymmetrical fold is one in which the axial plane is inclined. An overturned fold, or overfold, has the axial plane inclined to such an extent that the strata on one limb are overturned.

How do chevron folds form?

Chevron folds are a structural feature characterized by repeated well behaved folded beds with straight limbs and sharp hinges. Well developed, these folds develop repeated set of v-shaped beds. They develop in response to regional or local compressive stress. Inter-limb angles are generally 60 degrees or less.

What is recumbent fold?

A recumbent fold is one in which the axial plane is essentially horizontal, with the limit of variation of axial-planar dip, and the resulting limit of plunge, being 10° (Turner and Weiss, 1963; Fleuty, 1964). It is a sideways-closing neutral structure that is neither a synformal nor an antiformal fold.

What is a closed fold?

[¦klōzd ¦fōld] (geology) A fold whose limbs have been compressed until they are parallel, and whose structure contour lines form a closed loop. Also known as tight fold.

What are drag folds?

Definition of drag fold : a minor geological fold produced in soft or thinly laminated beds lying between harder or more massive beds in the limbs of a major fold.

What does a symmetrical fold look like?

A symmetrical fold is one in which the axial plane is vertical. A recumbent fold has an essentially horizontal axial plane. When the two limbs of a fold are essentially parallel to each other and thus approximately parallel to the axial plane, the fold is called isoclinal.

Why do rocks fold?

Causes of Geological Folds The folds arise as a result of the tectonic pressure and stress in the rocks and rather than fracture, they fold. They are easily visualized by the loss of horizontality of the strata. When tectonic forces acting on sedimentary rocks are a number of characteristic forms.

What is conjugate fold?

A set of paired, asymmetric folds whose axial planes dip towards one another. Limbs are commonly straight, and hinge zones short and angular. Conjugate folds are thought to be formed during the final stages of deformation.

What kind of stress causes recumbent fold?

Overturned and recumbent folds The stress of tectonic compression is commonly applied more forcefully in one direction as one tectonic plate collides with another. The directionally applied stress may result in folding that appears to be “pushed” from one direction.

What is open fold?

An open fold is a broad feature in which the limbs dip at a gentle angle away from the crest of the fold. Isoclinal folds have undergone greater stress that has compressed the limbs of the folds tightly together.

What is suprataneous folding in geology?

Suprataneous Folding: When folding and sedimentation are contemporaneous suprataneous folding is formed. The beds near the crest are thinner because the beds were rising. The beds near the troughs are thicker because the basin was sinking during sedimentation.

What is the function of the supraspinatus muscle?

It is a member of the rotator cuff, commonly remembered by the mnemonic “SITS” (supraspinatus, infraspinatus, teres minor, subscapularis). These muscles contribute to help form the glenohumeral joint, which aids in shoulder joint motion and stability.

What are the different types of folding?

1 Similar Folding: In this fo 2 Parallel Folding: In this t 3 Diaper Fold: This type of f 4 Disharmonic Folding: In thi 5 Suprataneous Folding: When 6 Decollement Fold:

What are isoclinal folds and chevron folds?

Isoclinal Fold: In Greek Isoclinal fold means the two limbs dip in the same direction but at the same angle. 7. Chevron Fold: Usually the crest and troughs of a fold are rounded, but sometimes the folds are characterised by sharp crests and troughs. Such folds where the crests and troughs are sharp and angular are called Chevron Folds.