| Autor: |
Slee, Adrian, McIntosh, Peter D. |
| Předmět: |
|
| Zdroj: |
Helictite: Journal of Australasian Speleological Research; 2019, Vol. 45, p27-37, 11p |
| Abstrakt: |
The discovery of significant cave and karst landscapes formed in quartzites and sandstones in South America, Africa and Australia has led to a debate among scientists over the definitions of karst and the processes forming karst in quartzites. In the past these caves were listed under the ambiguous definition of 'pseudokarst' landforms. It is now generally agreed that the chemical dissolution of silica within massive quartzite or sandstone units plays a significant role in the development of certain types of quartzite caves and the term syngenetic karst may better describe non-carbonate landscapes where dissolution and sediment transportation by erosion processes both play major roles in karst development. The recent discovery of towers formed within Precambrian orthoquarzite rock adjacent to Tertiary basalt on the edge of the Borradaile Plains in northern Tasmania poses questions regarding the processes of quartzite dissolution and karst development in silica rich rocks in an area that has had a subalpine or glacial climate for much of the Quaternary. It is suggested that the overlying basalt has been stripped from around the towers by Quaternary erosion and the caves have formed by arenisation induced by acidic upland soils. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
