Latest Plate tectonics Stories
Topics in the 26 March posting of GEOLOGY include anthropogenic impacts on the Indus River into the Arabian Sea; possible electrical conductivity beneath the Yellowstone hotspot track; mountain-forming volcanoes and deadly debris flows; melting beneath the Colorado Plateau; widespread weathered glass on Mars; and a new view into Mars' global aqueous history. GEOLOGY articles published ahead of print can be accessed online at http://geology.gsapubs.org/content/early/recent. When articles...
Scientists have recently finalized an expedition in an effort to learn more about an undersea mountain they say may have formed in a very different way than the rest of the seafloor. Aboard the JOIDES (Joint Oceanographic Institutions for Deep Earth Sampling) research ship, these scientists studied the formations and makeup of Atlantis Massif. This undersea mountain has been found to be made up of rocks typically found much deeper in the oceans crust. Other volcanic seamounts are usually...
A layer of partially molten rock about 22 to 75 miles underground can't be the only mechanism that allows continents to gradually shift their position over millions of years, according to a NASA-sponsored researcher. The result gives insight into what allows plate tectonics – the movement of the Earth's crustal plates – to occur. "This melt-rich layer is actually quite spotty under the Pacific Ocean basin and surrounding areas, as revealed by my analysis of seismometer data," says Dr....
Scientists interested in the construction of the rock layers immediately under the Earth’s crust, the lithosphere and asthenosphere, have new tools to help analyze these layers and further understand plate tectonics. The researchers have been using seismic waves to study the lithosphere-asthenosphere boundary, or LAB. This boundary is where the hot, convecting mantle asthenosphere and the overlying cold and rigid lithosphere meet. It has been found that seismic waves move faster...
GREENBELT, Md., March 22, 2012 /PRNewswire-USNewswire/ -- A layer of partially molten rock about 22 to 75 miles underground can't be the only mechanism that allows continents to gradually shift their position over millions of years, according to a NASA-sponsored researcher. The result gives insight into what allows plate tectonics - the movement of the Earth's crustal plates - to occur. (Logo: http://photos.prnewswire.com/prnh/20081007/38461LOGO) "This melt-rich layer is actually...
The ESA’s GOCE satellite has produced the first global high-resolution map of the boundary between the Earth’s mantle and its crust, according to an ESA press release. Understanding the mantle-or MoHo-could provide us with clues about the Earth’s interior. The Earth’s crust makes up only 1% total volume of our planet and is just the outermost shell. However, this 1% is very important to the overall makeup of the Earth. Geological resources such as oil and minerals are found in...
Highlights include several studies based in the U.S. Sierra Nevada, including a description of "magma fingers" and the formation of granite in the high Sierra crest near Yosemite National Park. Other studies investigate knickzones in the South Fork of the Eel River, California; the Rodgers Creek-Maacama fault system in the northern California Coast Ranges and its relation to the San Andreas fault; and the frequency and severity of destructive debris flows in the Pacific Northwest....
Geologists at the Universities of Bonn and Cologne have come up with a new idea as to how the earliest continents were formed The earth's structure can be compared to an orange: its crust is the peel supported by the earth's heavy mantle. That peel is made up of a continental crust 30 to 40 kilometers thick. It is much lighter than the thinner oceanic crust and protrudes from the earth's mantle because of its lower density, like an iceberg in the sea. "According to the current theory, the...
The first global high-resolution map of the boundary between Earth’s crust and mantle – the Moho – has been produced based on data from ESA’s GOCE gravity satellite. Understanding the Moho will offer new clues into the dynamics of Earth’s interior. Earth’s crust is the outermost solid shell of our planet. Even though it makes up less than 1% of the volume of the planet, the crust is exceptionally important not just because we live on it, but because is the place where all our...
Latest Plate tectonics Reference Libraries
The Pacific Ring of Fire, or Ring of Fire for short, is an area where a large number of earthquakes and volcanic eruptions occur in the basin of the Pacific Ocean. In a 25,000 mile horseshoe shape, it’s associated with an almost continuous series of oceanic trenches, volcanic belts, volcanic arcs and/or plate movement. The Ring of Fire contains 452 volcanoes and is home to over 75 percent of the world’s active and dormant volcanoes. It’s sometimes called the circum-Pacific belt or the...
Alfred Lothar Wegener (November 1, 1880 "“ November 2, 1930) was a German scientist, geologist, and meteorologist. He is best known for establishing the theory of the continental drift. His 1915 theory of continental drift surmised that the continents were slowly floating around the Earth. Most of his basis was strictly circumstantial evidence, and further he was not able to exhibit a mechanism for continental drift, which resulted in an unaccepted hypothesis until the 1950s. At that...
Peridotite is a dense, coarse grained ultrabasic rock, consisting mainly of the minerals olivine and pyroxene. Peridotite is also a group of mantle derived igneous rocks. They all are ultramafic or ultrabasic meaning they contain less than 45% silica and are high in iron and magnesium. Members of the peridotite family include: Dunite - predominately composed of olivine, with minor enstatite pyroxene and chromite. Harzburgite - composed of olivine, enstatite, and minor chromite....
Scoria is a term used by geologists to describe an igneous rock containing many gas bubbles, or vesicules. Scoria forms when magma rich in dissolved gases is vented. As the magma encounters lower pressures, the gasses are able to escape and form bubbles. These bubbles are trapped when the magma cools and solidifies. Volcanic cones of scoria can be left behind after eruptions, usually forming mountains with a crater at the summit. An example is Mount Wellington, Auckland in New Zealand....
Earth -- in geology and astronomy, fifth largest planet of the solar system and the only planet definitely known to support life. Gravitational forces have molded the earth, like all celestial bodies, into a spherical shape. However, the earth is not an exact sphere, being slightly flattened at the poles and bulging at the equator. The equatorial diameter is c.7,926 mi (12,760 km) and the polar diameter 7,900 mi (12,720 km); the circumference at the equator is c.24,830 mi (40,000 km)....
