A tor, which is also known by geomorphologists as either a castle koppie or kopje, is a large, free-standing rock outcrop that rises abruptly from the surrounding smooth and gentle slopes of a rounded hill summit or ridge crest. In the South West of England, the term is commonly also used for the hills themselves – particularly the high points of Dartmoor in Devon and Bodmin Moor in Cornwall.
Karlu Karlu / Devils Marbles Conservation Reserve is a protected area in the Northern Territory of Australia located in the locality of Warumungu about 105 km (65 mi) south of Tennant Creek, and 393 km (244 mi) north of Alice Springs. The nearest settlement is the small town of Wauchope located 9 km (5.6 mi) to the south.
In geomorphology and geology, a peneplain is a low-relief plain formed by protracted erosion. This is the definition in the broadest of terms, albeit with frequency the usage of peneplain is meant to imply the representation of a near-final stage of fluvial erosion during times of extended tectonic stability. Peneplains are sometimes associated with the cycle of erosion theory of William Morris Davis, but Davis and other workers have also used the term in a purely descriptive manner without any theory or particular genesis attached.
An inselberg or monadnock is an isolated rock hill, knob, ridge, or small mountain that rises abruptly from a gently sloping or virtually level surrounding plain. In Southern Africa a similar formation of granite is known as a koppie, an Afrikaans word from the Dutch diminutive word kopje. If the inselberg is dome-shaped and formed from granite or gneiss, it can also be called a bornhardt, though not all bornhardts are inselbergs. An inselberg results when a body of rock resistant to erosion, such as granite, occurring within a body of softer rocks, is exposed by differential erosion and lowering of the surrounding landscape.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
Spheroidal weathering is a form of chemical weathering that affects jointed bedrock and results in the formation of concentric or spherical layers of highly decayed rock within weathered bedrock that is known as saprolite. When saprolite is exposed by physical erosion, these concentric layers peel (spall) off as concentric shells much like the layers of a peeled onion. Within saprolite, spheroidal weathering often creates rounded boulders, known as corestones or woolsack, of relatively unweathered rock. Spheroidal weathering is also called onion skin weathering,concentric weathering,spherical weathering, or woolsack weathering.
A shield is a large area of exposed Precambrian crystalline igneous and high-grade metamorphic rocks that form tectonically stable areas. These rocks are older than 570 million years and sometimes date back to around 2 to 3.5 billion years. They have been little affected by tectonic events following the end of the Precambrian, and are relatively flat regions where mountain building, faulting, and other tectonic processes are minor, compared with the activity at their margins and between tectonic plates. Shields occur on all continents.
In glaciology, a roche moutonnée is a rock formation created by the passing of a glacier. The passage of glacial ice over underlying bedrock often results in asymmetric erosional forms as a result of abrasion on the "stoss" (upstream) side of the rock and plucking on the "lee" (downstream) side. Some geologists limit the term to features on scales of a metre to several hundred metres and refer to larger features as crag and tail.
Wave Rock is a natural rock formation that is shaped like a tall breaking ocean wave. The "wave" is about 15 m (50 ft) high and around 110 m (360 ft) long. It forms the north side of a solitary hill, which is known as "Hyden Rock". This hill, which is a granite inselberg, lies about 3 km (2 mi) east of the small town of Hyden and 296 km (184 mi) east-southeast of Perth, Western Australia. Wave Rock and Hyden Rock are part of a 160 ha (395-acre) nature reserve, Hyden Wildlife Park. More than 100,000 tourists visit every year.
Granite outcrops of Western Australia are weathered landforms that occur throughout the state of Western Australia, composed primarily of the rock type granite. All recognised types of this landform can be observed, commonly as bornhardts, but also as inselbergs, castle koppies and nubbins. Rising abruptly from the surrounding landscape they create a variety of microhabitats for plants, and provide seasonal resources and refuge for a range of animals. These areas thus have rich biodiversity and many endemic species. They are significant locations that tie in with the Aboriginal and European cultural heritage of Western Australia.
Granite domes are domical hills composed of granite with bare rock exposed over most of the surface. Generally, domical features such as these are known as bornhardts. Bornhardts can form in any type of plutonic rock but are typically composed of granite and granitic gneiss. As granitic plutons cool kilometers below the Earth's surface, minerals in the rock crystallize under uniform confining pressure. Erosion brings the rock closer to Earth's surface and the pressure from above the rock decreases; as a result the rock fractures. These fractures are known as exfoliation joints, or sheet fractures, and form in onionlike patterns that are parallel to the land surface. These sheets of rock peel off the exposed surface and in certain conditions develop domical structures. Additional theories on the origin of granite domes involve scarp-retreat and tectonic uplift.
The Kamiesberg or Kamiesberge, is a mountain range of jumbled granite inselbergs or bornhardts dotted over sandy plains and centered on Kamieskroon in Namaqualand in South Africa. This range is very like the Matopos of Zimbabwe in appearance. It stretches for about 140 km (60 mi) from Garies in the south to Springbok in the north and forms a plateau between the Sandveld of the Cape West Coast and Bushmanland in the east, with the Hardveld of the mountainous central Kamiesberg escarpment in the midst.
A bornhardt is a dome-shaped, steep-sided, bald rock outcropping at least 30 metres (100 ft) in height and several hundred metres in width. They are named after Wilhelm Bornhardt (1864–1946), a German geologist and explorer of German East Africa, who first described the feature.
Saprolite is a chemically weathered rock. Saprolites form in the lower zones of soil profiles and represent deep weathering of the bedrock surface. In most outcrops, its color comes from ferric compounds. Deeply weathered profiles are widespread on the continental landmasses between latitudes 35°N and 35°S.
In Earth science, a pothole is a smooth, bowl-shaped or cylindrical hollow, generally deeper than wide, found carved into the rocky bed of a watercourse. Other names used for riverine potholes are pot, (stream) kettle, giant's kettle, evorsion, hollow, rock mill, churn hole, eddy mill, and kolk. Although somewhat related to a pothole in origin, a plunge pool is the deep depression in a stream bed at the base of a waterfall. It is created by the erosional forces of turbulence generated by water falling on rocks at a waterfall's base where the water impacts. Potholes are also sometimes referred to as swirlholes. This word was created to avoid confusion with an English term for a vertical or steeply inclined karstic shaft in limestone. However, given widespread usage of this term for a type of fluvial sculpted bedrock landform, pothole is preferred in usage to swirlhole.
The Gornaya Shoria megaliths, meaning Mount Shoria megaliths, are rock formations forming part of Mount Shoriya in southern Siberia, Russia, lying to the east of the Altay Mountains.
A flared slope is a landform consisting in a rock-wall with a smooth transition into a concavity at the foot zone. Flared slopes form due to various weathering patterns that are more effective at the regolith or soil-covered base of rock walls. These landforms are common in granitic rocks but can also occur in other rock types such as ignimbrite. Flared slopes are found in a variety of different lithological and climatic environments in Australia, Spain, South Africa, and the western United States.
An etchplain is a plain where the bedrock has been subject to considerable "etching" or subsurface weathering. Etchplanation is the process forming etchplains. Contrary to what the name might suggest, etchplains are seldom completely flat and usually display some relief, as weathering of the bedrock does not advance uniformly. This means that weathering is unrelated to the flatness which might be derivative of various other processes of planation including peneplanation and pediplanation. Erosion of etchplains can result in the exposure of inselbergs such as bornhardt and tors. Generally the topography exposed at a stripped etchplain, that is an etch surface, after erosion of regolith is one with many irregularities as result of structurally defined areas of rock strength.
Climatic geomorphology is the study of the role of climate in shaping landforms and the earth-surface processes. An approach used in climatic geomorphology is to study relict landforms to infer ancient climates. Being often concerned about past climates climatic geomorphology considered sometimes to be an aspect of historical geology. Since landscape features in one region might have evolved under climates different from those of the present, studying climatically disparate regions might help understand present-day landscapes. For example, Julius Büdel studied both cold-climate processes in Svalbard and weathering processes in tropical India to understand the origin of the relief of Central Europe, which he argued was a palimpsest of landforms formed at different times and under different climates.
