How are Crenulations formed?

How are Crenulations formed?

Formation. Crenulations form when an early planar fabric is overprinted by a later planar fabric. The angular intersection of the two foliations causes a diagnostic texture called a crenulation, which may involve folding of the earlier mica foliations by the later foliation.

What does crenulated mean in biology?

crenulated. adj. (Biology) having a margin very finely notched with rounded projections, as certain leaves.

What does the term crenellations mean?

/ˌkren. əlˈeɪ.ʃənz/ a wall around the top of a castle, with regular spaces in it through which the people inside the castle can shoot: The towers were topped by medieval crenellations.

What are Crenulation folds?

Crenulation cleavages are zones of mineral differentiation that are coincident with the limbs of microfolds in crenulated fabrics. They consist of subplanar domains of highly oriented micaceous material that constitute preferred sites of parting in the rock.

What do Crenulations do?

Crenellation is a feature of defensive architecture, most typically found on the battlements of medieval castles. A battlement is a low, defensive parapet. The act of crenellation is the cutting of crenels into a previously solid and straight parapet wall.

What is sheath fold?

Sheath folds are cone-shaped struc- tures with an opening angle of less than 90° (Ramsay, 1979; Skjernaa, 1989; Marques et al., 2008). Entire sheath folds are rarely found in outcrops; more commonly cross-sections are exposed where the fold geometry is manifested by closed layers, so-called eye-structures (e.g. fig.

What does shoddily mean?

shoddily adverb (BADLY MADE) in a way that is careless, of poor quality, and that uses low quality materials: These clothes are very shoddily made. Many buildings in the area are shoddily constructed.

What is the meaning of schistose foliation?

External Websites. Schistosity, mode of foliation that occurs in certain metamorphic rocks as a consequence of the parallel alignment of platy and lath-shaped mineral constituents. It reflects a considerable intensity of metamorphism—i.e., changes resulting from high temperatures, pressures, and deformation.