The scientific theory of plate tectonics explains how landforms are created as a result of Earth’s subterranean movements. This relates to the undersea Flor Structure for the reason that in the 1960s a map flora showed a massive undersea mountain range that almost circled across the Earth scientist Harry Hess proposed that these ridges were the result of molded rocks, rising from the asthenosphere. it came to the surface, the rocks cold, making a new crush that was spreading away from seafloor and the ridge in a conveyer-belt motion. Decades later, the crash disappeared into the ocean trenches in a place called subduction zones and circled back into the earth. Magnetic data from the seafloor and related young age of oceanic crust, supported Hess’s theory of seafloor spreading.

The Sea of Cortés exists geographically because of plate tectonics. Movement of the Pacific and North American crustal plates began ripping the Baja peninsula and the western half of Southern California from mainland Mexico some six million years ago, opening up the Sea of Cortés in the process. Since then, the Pacific plate has moved some 330 km 200 miles northwards carrying Baja California and peninsular Southern California with it.

It all started in the late Jurassic period 140 million years ago geologist I have studied the rock formations at this time. And have discovered that conditions here were much more difficult than right now western northern America looked much like western Indonesia, with many offshore for Canik, islands and deep oceanic trench. The North America plate bears sediments brought in by rivers and streams along with volcanic deposits, reaching a thickness of many thousands of feet. The Farallon Plate, formed from igneous rock called basalt and shown here in black, slides underneath the North American Plate. Volcanic islands fed by the partial melting of the Farallon Plate, due to high pressure and temperature at great depth, form just east of the deep ocean trench that marks the boundary between the North American Plate and the Farallon Plate.

In the Middle Cretaceous Period which was 80 million years later the great thickness of Continental Sediments and volcanic rocks deposited upon the North American Plate are compressed into a great mountain range similar to the Andes in South America. The cold massive basaltic slab of the Farallon Plate continues to slide underneath the North American Plate. Giant magma bodies melt up into the overlying crumpled Jurassic age sediments, destroying much and cooking the rest to form a metamorphic rock. New volcanoes form on top of this great mountain range. Continuing the Late Cretaceous, which was 85 million years later 

Mountain building begins to slow down. Erosion reduces the great Andean style mountain ranges. The giant magma bodies cool into large masses of igneous rock. These large structures are called batholiths and continued erosion eventually brings them to the surface. The volcanoes of previous times are eroded away and are replaced by new volcanoes. The Farallon Plate continues to slide slowly beneath the North American Plate

citation:

illustration :https://education.nationalgeographic.org/resource/plate-tectonics/

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Last Updated

August 17, 2022