: a large dome-shaped rock mass (as of granite) produced by exfoliation.
What is an exfoliation dome and how does it form?
Exfoliation is a form of mechanical weathering in which curved plates of rock are stripped from rock below. This results in exfoliation domes or dome-like hills and rounded boulders. … One after another these layers are spalled off resulting in rounded or dome-shaped rock forms.
What causes exfoliation domes?
UNLOADING–removal of rock overburden causes rocks that were under pressure to expand, creating joints, cracks in a rock that have not had appreciable movement of rock along the cracks. The process of expansion by unloading leads to “sheeting” that forms exfoliation domes (such as in Yosemite National Park, CA).
What is exfoliation in geology?
Exfoliation is a process in which large flat or curved sheets of rock fracture and are detached from the outcrop due to pressure release: As erosion removes the overburden from a rock that formed at high pressure deep in the Earth´s crust, it allows the rock to expand, thus resulting in cracks and fractures along sheet …
What is granite exfoliation dome?
Exfoliating granite is a granite undergoing exfoliation, or onion skin weathering (desquamation). The external delaminated layers of granite are gradually produced by the cyclic variations of temperature at the surface of the rock in a process also called spalling.
What is a good example of an exfoliation dome?
This process is called exfoliation; large rounded landforms (usually intrusive rocks) that result from this process are called exfoliation domes. Examples of exfoliation domes are Stone Mountain, Georgia, and Half Dome in Yosemite National Park.
What is exfoliation and sheeting?
Exfoliation is the term used to describe the peeling away of sheets of rock millimeters to meters in thickness from a rock’s surface due a range of physical and chemical processes during exhumation and weathering .
Where is exfoliation most likely to occur?
Where is exfoliation most likely to occur? Exfoliation occurs mostly in mountain regions where intrusive igneous rock has been uplifted and exposed by erosion.
What causes exfoliation in granite?
Exfoliation is common in granite, an intrusive igneous rock which is formed deep within the crust and under great pressure from the overlying materials. When granitic rocks are moved to the surface by tectonic processes, the pressure is released and the granite expands slightly, resulting in exfoliation.
What is the difference between exfoliation domes and exfoliated tors?
Exfoliated tors are formed due to expansion and unloading of rocks. Exfoliation domes are formed due to the expansion of rocks caused by change in temperature.
What is exfoliation in geography where it is commonly found?
exfoliation, separation of successive thin shells, or spalls, from massive rock such as granite or basalt; it is common in regions that have moderate rainfall. The thickness of individual sheet or plate may be from a few millimetres to a few metres.
What is exfoliation of soil?
Exfoliation: When temperature of rocks rapidly changes that can expand or crack rocks. This especially happens with granitic rocks as they were cooling, like at Yosemite National Park. … If moisture seeps into cracks before winter, it can then freeze, driving the rocks apart.
What is unloading and exfoliation?
The first type of weathering is exfoliation, also called unloading, which is when the outer layers of rock break away from the rest of the rock. … An example of exfoliation is Half Dome in Yosemite National Park, which formed after glaciers caused surface rock to be removed.
Why is granite so susceptible to unloading and exfoliation?
Granitic rock tends to exfoliate parallel to the exposed surface because the rock is typically homogenous, and it doesn’t have predetermined planes along which it must fracture. … Frost wedging is the process by which water seeps into cracks in a rock, expands on freezing, and thus enlarges the cracks (Figure 5.5).