Evidence for Mantle Plume-Rift-Continent Interaction

Hot ascending mantle plumes in the Earth’s mantle are an important driving force in plate tectonics. With an assumed diameter of the plume heads of up to several thousand kilometers, the amount of hot material ascending from the core mantle boundary at 2900 km depth is sufficient to migrate through the continental lithosphere.

ocean_bottom_magma

This process leads to the eruption of large volcanic material (flood basalts) at the Earth’s surface. This is also the case for Southern Africa and South America: the Parana/Etendeka/ flood basalt provinces are the direct consequences of the Gondwana break-up starting some 130 million years ago. Traces of the break-up process can be found on the newly formed ocean floor – the Walvis Ridge off the coast of Northern Namibia images the track of the mantle plume.

In order to study these processes, German scientists investigated structures which are related to the break-up process of Gondwana in the South Atlantic. The upwelling of large amounts of hot mantle material produces regions of crustal and mantle rocks with different seismic velocities (with respect to the surrounding, unaffected regions). In cooperation with colleagues from AWI and GEOMAR, and with the support of the Geological Survey of Namibia, scientists from GFZ have carried out extensive seismic investigations on and offshore Northern Namibia. The crustal structure was investigated along several seismic lines.

“For the first time we could obtain images of the deeper crustal structure in the region where the Walvis Ridge joins the African continent, in order to study the impact of a mantle plume” explains Trond Ryberg from GFZ. “Our seismic investigations found a distinctive high-velocity anomaly in the lower crust between 20 and 40 km depth.”

This region of anomalously high seismic velocities can be related to the intrusion of magmatic material in the lower crust of the Earth. This was expected according to the current perception. But surprisingly, the size of the anomaly was far too small to be created by a large plume head playing an active role in the break-up process. Trond Ryberg: “The crustal structure in the investigated region reflects the general process of continental break-up rather than the immediate impact of the plume head on the lithosphere. In addition, we were able to reconstruct the direction of the mantle plume flow”.

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About Earth Changes Media w/ Mitch Battros

Mitch Battros is a scientific journalist who is highly respected in both the scientific and spiritual communities due to his unique ability to bridge the gap between modern science and ancient text. Founded in 1995 – Earth Changes TV was born with Battros as its creator and chief editor for his syndicated television show. In 2003, he switched to a weekly radio show as Earth Changes Media. ECM quickly found its way in becoming a top source for news and discoveries in the scientific fields of astrophysics, space weather, earth science, and ancient text. Seeing the need to venture beyond the Sun-Earth connection, in 2016 Battros advanced his studies which incorporates our galaxy Milky Way - and its seemingly rhythmic cycles directly connected to our Solar System, Sun, and Earth driven by the source of charged particles such as galactic cosmic rays, gamma rays, and solar rays. Now, "Science Of Cycles" is the vehicle which brings the latest cutting-edge discoveries confirming his published Equation.
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