OMAN OPHIOLITES - A GULF HAVEN OF A DIFFERENT KIND

摘要

The face of the Earth is being continually remodelled thanks to the processes like tectonic activity, volcanism and erosion. Looked on a broader scale, behind all these 'peripheral' activities there is one underlying cause, which is solid-state convection in the mantle. Mantle convection is essentially driven by contrasts in density induced by the thermal expansion of silicates. At the characteristic temperature of around 1000 deg C, the silicate minerals that make up the mantle can flow at rates of several centimetres per year. One of the most important objectives of Earth science studies therefore is to determine the thermal structure of the mantle.