The eclogites and garnet-chloritoid schists occur in the the Alag Khadny metamorphic complex, Chandman district, Lake Zone, SW Mongolia, which are located in the central parts of the Central Asian Orogenic Belt. The ophiolite belts and basement block (microcontinent) are geologically associated with the metamorphic complex. The eclogites and associated garnet-chloritoid schists occur as lenses and boudins in the matrix of marbles.

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Extreme thermal condition of metamorphism in continental deep crust is an enigmatic issue. Moreover, the post-peak thermal relaxation history of such orogenic deep crust is also not properly known. In view of this, we have chosen an aluminous granulite from Eastern Ghats, India to study their thermal history and to calculate cooling rate(s). Compositional profile across the interface between garnet-orthopyroxene reveals homogeneous garnet composition yielding near-peak temperature of 930^oC, while that across garnet-(Ti-F)biotite yields temperature of 800-875^oC with a zoning profile in garnet. Diffusion kinetics modeling of such zoning profile yields anomalously high cooling rate of ~12-25^oC/ky at 875^oC.

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The Hiraodai Karst Plateau is mainly consist of crystalline limestone, and is designated as natural monument, so strictly prohibited from breaking exposure.  We tried to measure the crystal size distribution from the photograph of exposure surface.  According to the relationship between the grain size and temperature discussed in Covey-Crump & Rutter (1989), more than 640 degree of centigrade temperature is estimated.

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