The book summarizes the occurrence, geochemistry, mineralogy, petrology and phase-equilibria studies in air and under high pressures related to the most intriguing group of potassium-rich mafic and ultramafic rocks, often including host of exotic mineral assemblages including feldspathoids. Mantle-derived K-rich melts had intrigued most of the founders of Geology and many of the later experts in the field of Igneous Petrology, because they are sometimes associated with carbonatites and even diamond. They tend to contain anomalous concentration of many such elements as K, Rb, Sr, U, F, P, etc., along with Ni, Co and Cr indicating a mixture of crust and mantle materials. Although these rocks occur rarely in ancient geologic time, they have been erupting mostly in modern geological history (less than last 120 Ma or so). Are the old age data real or the result of a sampling problem? Modern observations leave no doubt that sediments must be subducted on a large scale. There is now evidence that the upper mantle (and perhaps even the lower mantle) is not homogeneous but rather like a fruit cake, and that there are thermal anomalies in the mantle resulting from deep mantle plumes or subduction. Is this related to release of these unusual rocks clearing the mantle of left over subduction materials? This volume, written for those interested in the geochemistry of K-rich melts from the deep Earth, reviews the present state of knowledge of these unique igneous rocks. The author is an expert in the field of Igneous Petrology and the book will serve as a valuable reference book for researchers and academicians in the discipline.

The book summarizes the occurrence, geochemistry, mineralogy, petrology and phase-equilibria studies in air and under high pressures related to the most intriguing group of potassium-rich mafic and ultramafic rocks, often including host of exotic mineral assemblages including feldspathoids. Mantle-derived K-rich melts had intrigued most of the founders of Geology and many of the later experts in the field of Igneous Petrology, because they are sometimes associated with carbonatites and even diamond. They tend to contain anomalous concentration of many such elements as K, Rb, Sr, U, F, P, etc., along with Ni, Co and Cr indicating a mixture of crust and mantle materials. Although these rocks occur rarely in ancient geologic time, they have been erupting mostly in modern geological history (less than last 120 Ma or so). Are the old age data real or the result of a sampling problem? Modern observations leave no doubt that sediments must be subducted on a large scale. There is now evidence that the upper mantle (and perhaps even the lower mantle) is not homogeneous but rather like a fruit cake, and that there are thermal anomalies in the mantle resulting from deep mantle plumes or subduction. Is this related to release of these unusual rocks clearing the mantle of left over subduction materials? This volume, written for those interested in the geochemistry of K-rich melts from the deep Earth, reviews the present state of knowledge of these unique igneous rocks. The author is an expert in the field of Igneous Petrology and the book will serve as a valuable reference book for researchers and academicians in the discipline.

The Indian National Science Academy was established in January 1935 with the objective of promoting science in India and harnessing scientific knowledge for the cause of humanity and national welfare. In 1968 it was designated as the adhering organisation in India to the International Council for Scientific Union (ICSU) on behalf of the Government of India. Over the years, the Academy has published a number of journals, volumes, biographical memoirs, etc. The year 2009-2010 will be specially celebrated to mark the Platinum Jubilee of the Academy. Many programmes are planned in different centres in India on this occasion. In addition, the Academy has decided to publish a number of special volumes on different s- jects ranging from earth sciences to life sciences. This volume is on Physics and Chemistry of the Earth's Interior. One of the main objectives of geophysicists is to establish the internal structure of the earth as revealed by seismic tomography. It is also their primary goal to correlate geophy- cal data to reveal thermal and chemical state of the crust, mantle and core of the earth. In - der to interpret seismic velocities and associated density and elastic properties in terms of mineralogical and petrological models of the earth's interior, thermodynamic and hi- pressure temperature data from mineral physics are essential. With the advent of different types of multi-anvil and laser-heated diamond anvil equipment, it is now possible to simulate conditions prevalent even in the lower mantle and core of the earth.