Mantle (geology)

Mantle (geology) is the thick layer of rock beneath the Earth's crust, extending from a depth of about 35 kilometers to 2,900 kilometers, making up about 84% of the Earth's volume, and is divided into the upper mantle and the lower mantle. The mantle is composed of silicate minerals and is separated from the Earth's core by the Gutenberg discontinuity, a boundary discovered by Benno Gutenberg. The study of the mantle is crucial to understanding the Earth's plate tectonics, as it is the driving force behind the movement of tectonic plates, such as the Pacific Plate and the North American Plate. This movement is influenced by the Earth's rotation and the Moon's gravitational pull.

Introduction

The Earth's mantle is a complex and dynamic system, with its own unique geological processes, such as convection currents and subduction zones, which are studied by geologists like Harry Hess and Marie Tharp. The mantle plays a crucial role in shaping the Earth's surface, with its movement influencing the formation of mountain ranges, such as the Himalayan mountain range and the Andes mountain range. The study of the mantle is also closely tied to the study of volcanology, as volcanic eruptions are often the result of magma rising from the mantle, as seen in the 1980 eruption of Mount St. Helens and the 2010 eruption of Eyjafjallajökull. The United States Geological Survey (USGS) and the National Oceanic and Atmospheric Administration (NOAA) are two organizations that study the Earth's mantle and its effects on the environment.

Composition

The mantle is composed of silicate minerals, such as olivine, pyroxene, and garnet, which are rich in iron, magnesium, and calcium. The exact composition of the mantle is still a topic of research, with scientists like Inge Lehmann and Beno Gutenberg making significant contributions to our understanding of the Earth's interior. The mantle also contains water and carbon dioxide, which can affect its viscosity and density, as studied by geophysicists like Adam Dziewonski and Don L. Anderson. The International Union of Geological Sciences (IUGS) and the Geological Society of America (GSA) are two organizations that study the composition of the Earth's mantle.

Temperature_and_Pressure

The temperature and pressure conditions in the mantle vary greatly with depth, ranging from about 500°C to 3000°C and 2.5 to 140 GPa, respectively, as measured by seismologists like John Michell and Charles Francis Richter. The Earth's core is the hottest part of the planet, with temperatures reaching up to 6000°C, as studied by geophysicists like Francis Birch and Orson Anderson. The pressure in the mantle is so great that it causes the minerals to undergo phase transitions, resulting in changes to their crystal structure and physical properties, as researched by scientists like Pierre-Simon Laplace and William Thomson (Lord Kelvin).

Mantle_Dynamics

The mantle is a dynamic system, with convection currents driving the movement of tectonic plates, as described by Alfred Wegener and Arthur Holmes. The mantle is also home to hotspots, such as the Hawaii hotspot and the Iceland hotspot, which are thought to be the result of plumes rising from the Earth's core-mantle boundary, as studied by geologists like Jason Morgan and W. Jason Morgan. The European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA) are two organizations that study the dynamics of the Earth's mantle.

Boundary_Layers

The mantle is bounded by several distinct layers, including the Mohorovičić discontinuity (Moho), which separates the mantle from the Earth's crust, and the Gutenberg discontinuity, which separates the mantle from the Earth's core. The D'' layer is a thin layer at the base of the mantle, characterized by a unique seismic signature, as researched by seismologists like Bullen Keith Edward and Hiroo Kanamori. The Earth's lithosphere is the outermost solid layer of the planet, comprising the crust and the uppermost part of the mantle, as studied by geologists like James Hutton and Charles Lyell. The American Geophysical Union (AGU) and the Royal Astronomical Society (RAS) are two organizations that study the boundary layers of the Earth's mantle. Category:Geology