aving considered the Earth’s formation in the last chapter, let’s now use the tools of geochemistry we acquired in the first eight chapters to consider how the Earth works. The Earth, unlike many of its neighbors, has evolved over its long history and it remains geologically active. Four and a half billion years later, it is very different place than it was first formed. Certainly one of the ma...

Samples of the Moon obtained from the Apollo and Luna missions, as well as from lunar meteorites found haphazardly on Earth, are a testament to the violent origin and early evolution of the Earth–Moon system. The prevailing paradigm for the origin of the Moon derived from these samples posits that a Mars-sized object collided with the proto-Earth about 4.5 billion years ago, placing in Earth or...

The distribution of the count rate of neutrons (per second) near the Earth’s surface for two directions: towards the Earth and away from it, is studied using the experimental data, obtained in Moscow during 1996. The analysis shows that the mathematical approximation of the neutron count rate distribution can be described by a sum of two functions: a Poison distribution and a log-normal distrib...

Antineutrinos born in the U and Th decay chains inside the Earth (“Geoneutrinos”) carry out information on the amount and distribution of radiogenic heat sources, which is of fundamental importance for geophysics. Models of the Earth distribute U and Th masses mainly between the continental crust and the lower mantle. It has been much discussed recently that a number of detectors stationed at a...

The long-favored paradigm for the development of continental crust is one of progressive growth beginning at approximately 4 billion years ago (Ga). To test this hypothesis, we measured initial 176Hf/177Hf values of 4.01- to 4.37-Ga detrital zircons from Jack Hills, Western Australia. epsilonHf (deviations of 176Hf/177Hf from bulk Earth in parts per 10(4)) values show large positive and negativ...