The book attempts to draw together the various strands of evidence that have led to present knowledge of the distribution of density throughout the interior of the Earth. Details are also given of other properties with which the density is closely linked, including pressure, compressibility and compression, rigidity, seismic velocities, Poisson's ratio and gravitational intensity. Questions of thermodynamics and chemical composition and phase enter discussions where they bear more or less sharply on the density determination; but the book does not purport to be a comprehensive text on the Earth's internal tem perature distribution and composition. The density distributions of other planets are discussed. The quest for clues on the Earth's internal densities has long been an exciting one, and an aim of the book is to present a developing story which has fascinated the author over much of his worl(ing life. The early chapters refer to key developments from ancient times to around 1930. The later chapters recount, in greater detail, develop ments since 1930. The stage has now been reached where numerous published papers bearing on the Earth's density seem to do little more than fidget around the resolving power of long accumulated observational data. So the present seems an appropriate time to try to put some perspec tive into the story. Of course, the story will never be quite finished: in describing the interior of the Earth, there will always be extra decimal places to add as further significant evidence arises.

This book is an appealing, concise, and factual account of the chemistry of the solar system. It includes basic facts about the chemical composition of the different bodies in the solar system, the major chemical processes involved in the formation of the Sun, planets, and small objects, and the chemical processes that determine their current chemical make-up. The book summarizes compositional data but focuses on the chemical processes and where relevant, it also emphasizes comparative planetology. There are numerous informative summary tables which illustrate the similarities (or differences) that help the reader to understand the processes described. Data is presented in graphical form which is useful for identifying common features of the major processes that determine the current chemical state of the planets. The book will interest general readers with a background in chemistry who will enjoy reading about the chemical diversity of the solar system's objects. It will serve as an introductory textbook for graduate classes in planetary sciences but will also be very popular with professional researchers in academia and government, college professors, and postgraduate fellows.

Geology - The Key Ideas is a definitive introduction to the nature and workings of the Earth. Extensively illustrated it covers everything from earthquakes and plate tectonics to the formation of rocks and minerals. With clear explanations of complex geological processes, and a glossary of specialist terms, this book will give you a new understanding of the planet we live on. NOT GOT MUCH TIME? One, five and ten-minute introductions to key principles to get you started. AUTHOR INSIGHTS Lots of instant help with common problems and quick tips for success, based on the author's many years of experience. EXTEND YOUR KNOWLEDGE Extra online articles at www.teachyourself.com to give you a richer understanding. THINGS TO REMEMBER Quick refreshers to help you remember the key facts.

In the dozen years since the first edition appeared, there has been a great advance in understanding of the Earth's deep interior. This is not because there have been breakthroughs in understanding, or even many changes of ideas, but largely because of many small advances, often the result of improved tech niques. This has led to a complete revision of the book. For instance, we have a much better idea of how the cloud of gas that formed the Solar Nebula evolved into the Sun and the planets, and of the chemical processes that accompanied its evolution and determined the mix of elements in the Earth. We have a better understanding of convection and how plates are an essential part of it, and how it is accompanied by chemical processes that have extracted the materials to build continents. Although the major variation within the Earth is radial, improved geophysical and geochemical techniques have made progress in investigating and under standing the lateral heterogeneities, and it is encouraging that when geochemists and geophysicists talk about lateral heterogeneities they can sometimes be referring to the same thing. Plumes have become very fashionable as the cause of hot-spot magmatism and associated geochemical anomalies, probably origi nating at the base of the mantle (though clear evidence for their existence is lacking).

The past few decades have witnessed the growth of the Earth Sciences in the pursuit of knowledge and understanding of the planet that we live on. This development addresses the challenging endeavor to enrich human lives with the bounties of Nature as well as to preserve the planet for the generations to come. Solid Earth Geophysics aspires to define and quantify the internal structure and processes of the Earth in terms of the principles of physics and forms the intrinsic framework, which other allied disciplines utilize for more specific investigations. The first edition of the Encyclopedia of Solid Earth Geophysics was published in 1989 by Van Nostrand Reinhold publishing company. More than two decades later, this new volume, edited by Prof. Harsh K. Gupta, represents a thoroughly revised and expanded reference work. It brings together more than 200 articles covering established and new concepts of Geophysics across the various sub-disciplines such as Gravity, Geodesy, Geomagnetism, Seismology, Seismics, Deep Earth Processes, Plate Tectonics, Thermal Domains, Computational Methods, etc. in a systematic and consistent format and standard. It is an authoritative and current reference source with extraordinary width of scope. It draws its unique strength from the expert contributions of editors and authors across the globe. It is designed to serve as a valuable and cherished source of information for current and future generations of professionals.