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EARTH SCIENCE > Land Surface > Geomorphology > Tectonic Landforms/Processes

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  • Key geological boundaries were identified and mapped onto aerial photos and satellite images.

  • The collection consists of over 1 tonne of rock samples from the Theron Mountains, with an emphasis on the mainline of the enscarpment, which was reached by climbing the scree slopes at the base of the cliffs or by traversing the skyline, during the 2004/2005 field season.

  • Field observations made during the 2004-2005 field season, using such features as sill steps, sill bridges, orientated phenocrysts and asymmetric structures to determine regional magma flow directions in the Theron Mountains. A full photographic record of the cliffs was made at a transit of 1km out from the cliffs.

  • Laboratory AMS (Anisotropy of Magnetic Susceptibility) measurements made on a collection of sill samples collected from the Theron Mountains, Antarctica, during the 2004-2005 field season. AMS involves the collection of some 1 metric tonne of oriented samples and the lab-based determination of the magmatic flow fabric of the rock. Models concerning the location of mantle plumes and triple junctions associated with the Mesozoic break-up of Gondwana in the Antarctic-southern Africa sector are not capable of independent testing, other than by geochemical and age dating methods. We determined the regional flow directions of the magmas in dyke and sill complexes in the areas of postulated plume heads and related triple points on the opposing conjugate margins. AMS was utilised to determine magmatic flow directions and constrain these with macroscopic observations of flow indicators.

  • The British Antarctic Survey holds one of the most extensive collections of Antarctic rocks and fossils anywhere in the world. These are predominately from the Antarctic Peninsula region and Scotia Arc, although there is also important material from areas such as the Ellsworth Mountains, Marie Byrd Land and the Transantarctic Mountains. Some of these specimens go back to the very earliest days of the Falkland Islands Dependencies Survey in the 1940s, and include collections made by the pioneer geologists at bases such as Hope Bay and Deception Island. Right from the outset, every specimen collected in Antarctica has been numbered and catalogued, and a vast reference archive is now available for use by the geoscience community. We currently have information relating to 150,000 field samples often with associated analysis data such as geochemistry. Additionally we hold a variety of data for nearly 500 marine cores. Metadata and data are stored digitally within a number of Oracle 10g database tables and for some datasets such as the type and figured fossil collection there is external access through a web interface. However, a significant number of datasets exist only in analog form and are held within the BAS archives organised by individual geologist. This abstract acts as an overview of the BAS geological data - both terrestrial and marine.

  • The dataset consists of Ar-Ar isotope dating, field data, and selected geochemical analysis of igneous dykes and sills collected from Dronning Maud Land during the 2000-2001 field season. The aim was to measure ages of volcanism during flood basalt events in Dronning Maud Land associated with the breakup of Gondwana.The style and volume of magmatism varies between margins from large volume flood basalts such as the Parana or Deccan provinces to less volumetric margins such as the southern part of the South Atlantic. This case (Collaborative Awards in Science and Engineering) studentship was intended to provide support to study the evolution of the break-up of Africa and East Antarctica which occurred in the early Jurassic. An extended period of magmatism has been suggested for this margin associated with complex extensional tectonics. A combined geochronological / geochemical approach was used to understand the evolution of the crust and sub-continental lithospheric mantle during the break-up of one central portion of the Gondwana super continent.

  • Igneous dykes and sills were collected from Dronning Maud Land during the field season 2000-2001. The aim was to measure ages of volcanism during flood basalt events in Dronning Maud Land associated with the breakup of Gondwana. The style and volume of magmatism varies between margins from large volume flood basalts such as the Parana or Deccan provinces to less volumetric margins such as the southern part of the South Atlantic. This CASE (Collaborative Awards in Science and Engineering) studentship was intended to provide support to study the evolution of the break-up of Africa and East Antarctica which occurred in the early Jurassic. An extended period of magmatism has been suggested for this margin associated with complex extensional tectonics. A combined geochronological / geochemical approach was used to understand the evolution of the crust and sub-continental lithospheric mantle during the break-up of one central portion of the Gondwana super continent.