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A shield is a large area of exposed Precambrian crystalline igneous and high-grade metamorphic rocks that form tectonically stable areas. [1] These rocks are older than 570 million years and sometimes date back to around 2 to 3.5 billion years.
Straight, which are found in the most tectonically incised/active areas. This is more of a hypothetical end-member, and are not often found in nature. Straight-type channels can be found at alluvial fans. Braided rivers, which form in (tectonically active) areas that have a larger sedimentary load than the discharge of the river and a high ...
The thickness of alluvial fans forming due to basin margins are influenced tectonically. [3] If the alluvial fan gets thicker and the grains become more coarse heading up the fan, this indicates that the basin margin is tectonically active and the building of the alluvial fan being more active than the deposition rate.
For purposes of this list, a major plate is any plate with an area greater than 20 million km 2 (7.7 million sq mi) African plate – Tectonic plate underlying Africa – 61,300,000 km 2 (23,700,000 sq mi) Antarctic plate – Major tectonic plate containing Antarctica and the surrounding ocean floor – 60,900,000 km 2 (23,500,000 sq mi)
The only active volcanism in the last 200 years has been on Hawaiʻi and on the submerged but growing volcano to the extreme southeast, Kamaʻehuakanaloa (formerly Loʻihi). Almost all of the magma of the hotspot has the composition of basalt , and so the Hawaiian volcanoes are composed almost entirely of this igneous rock.
The volcano formed in a tectonically active area known for phreatomagmatic eruptions. These eruptions are the interaction of magma and water, which cause explosive eruptions that can eject such ...
Seismotectonics is the study of the relationship between earthquakes, active tectonics, and individual faults in a region. It seeks to understand which faults are responsible for seismic activity in an area by analysing a combination of regional tectonics, recent instrumentally recorded events, accounts of historical earthquakes, and ...
Plate tectonics (from Latin tectonicus, from Ancient Greek τεκτονικός (tektonikós) 'pertaining to building') [1] is the scientific theory that Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago.