What is a Cratonic basin?
Cratonic basins are sites of prolonged, broadly distributed but slow subsidence of the continental lithosphere, and are commonly filled with shallow water and terrestrial sedimentary rocks. They remain poorly understood geodynamically.
How do cratonic basins form?
Basins are commonly found along aulacogens that formed prior to the basin. Domes and arches are found between aulacogens. It is possible that cooling of the lithosphere and upper mantle following a period of heating, crustal stretching, and erosion along aulacogens is responsible for the subsidence of cratonic basins.
What is cratonic River?
Introduction. Amongst the half a dozen cratons of the Indian shield, the Dharwar Craton is considered to be one of the ancient Precambrian terrains of the world. The Kaveri (also Cauvery) River drains this ancient land surface. A significant portion of the river basin is underlain by rocks of Archaean–Proterozoic age.
What is sedimentary zone?
Sedimentary basins are regions of the Earth where long-term subsidence creates accommodation space for accumulation of sediments. As the sediments are buried, they are subject to increasing pressure and begin the processes of compaction and lithification that transform them into sedimentary rock.
What are cratons made of?
Cratons are generally found in the interiors of continents and are characteristically composed of ancient crystalline basement crust of lightweight felsic igneous rock such as granite. They have a thick crust and deep roots that extend into the mantle beneath to depths of 200 km.
What are cratons known for?
craton, the stable interior portion of a continent characteristically composed of ancient crystalline basement rock. The term craton is used to distinguish such regions from mobile geosynclinal troughs, which are linear belts of sediment accumulations subject to subsidence (i.e., downwarping).
What is Purana basin?
Purana Basins – summary • Includes only sedimentary successions of Proterozoic age that. occur in numerous basins in the peninsular India. • They are largely unmetamorphosed, undeformed (only. slightly) deformed at basin margins, without body fossils (any. part of the actual animal or plant)
Why are cratons so old?
Cratons are made up of lighter (chemically buoyant) materials, they are highly viscous (100–1,000 times more than surrounding rock), and they are almost twice as thick as younger lithosphere. With these conditions working in their favor, it makes sense that cratons have remained stable over billions of years.
How do you identify a craton?
Structure. Cratons have thick lithospheric roots. Mantle tomography shows that cratons are underlain by anomalously cold mantle corresponding to lithosphere more than twice the typical 100 km (60 mi) thickness of mature oceanic or non-cratonic, continental lithosphere.
What is a cratonic basin?
Cratonic basins are sites of prolonged, broadly distributed but slow subsidence of the continental lithosphere, and are commonly filled with shallow water and terrestrial sedimentary rocks. They remain poorly understood geodynamically.
Is there a mechanism for continental erosion in the cratonic interior?
In the cratonic interior, however, glaciation remains the only plausible mechanism that satisfies the required timing, magnitude, and broad spatial pattern of continental erosion revealed by our thermochronological inversions.
What is the Centralian basin?
The Centralian oriented at a high angle to the plate margin. with or without the involvement of mantle plumes. history of selected basins. basin known. It overlies deeply eroded (during the or and Natal’in 1996). Table 30.1. Selection of basins on the North American, South American and African plates with their ages of initiation of the basin.
How did the breakup of Rodinia supercontinent affect the Tarim Basin?
During the Rodinia supercontinent cycle, the breakup of Rodinia supercontinent affected the development and evolution of main cratonic basin in the world (Allen and Armitage, 2011; Persaudet al., 2017). The Tarim Basin, initialed in a continental rifting environment, was related to the breakup of Rodinia supercontinent.