Metal deposits in sedimentary rocks are frequently of controversial origin. This being so, any new approach that has bearing on the genesis of ores in sediments is important. Both epigenetic and syngenetic theories have been invoked for most stratabound deposits. Also, the relative importance of normal sedimentary processes and unusual processes, such as volcanogenic exhalations, has been debated at length. Trace- or minor-element studies of most types of metal deposit have been undertaken by a number of geologists with varying success. This paper reviews some of the more recent geochemical work on certain classes of ores in sediments and relates the geochemical data to the prevalent theories of origin of the deposits.  <...>

Numerous detailed studies of stratiform  copper deposits reported in recent years have rejected the classic igneous-hydrothermal epithermal/telethermal origin for such mineralization, and have instead suggested that an origin intimately related to the processes of sedimentation would be much more suited to the observed character of these deposits. Overwhelming features, such as the widespread continuity of mineralization within a sedimentary basin and the distribution of mineralization within narrow stratigraphic limits, are commonly cited as evidence of sedimentary origins. However, such features do not exclude the possibility of diagenetic additions of ore metals to particularly favorable stratigraphic horizons, and in fact recent studies indicate repeatedly that one or more diagenetic events preceded the deposition of ore metals. For example, the deposition of iron sulfides, and in some cases sulfate-bearing minerals, is commonly observed to have occurred before the introduction of ore-stage metals. <...>

Many important decisions, ranging from locating an oil prospect or a land-fill site to determining the location and size of an earthquake-producing fault, are based on geological maps. Because a map-scale structure is never completely sampled in three dimensions, geological maps and the cross sections derived from maps are always interpretations. The interpretation may be complicated by direct structural observations, like bedding attitudes, that are misleading because they represent a local structure, not the map-scale structure.

Milestones mark great events: walking on the moon, analyzing rocks on Mars, flying a self-propelled, heavier-than-air machine, using a Bunsen burner for flame atomic spectrometry, and perhaps employing an atmospheric pressure plasma mass spectrometry as an ion source for solution mass spectrometry. Yes, inductively coupled plasma mass spectrometry (ICP-MS) ranks among the milestone inventions of spectrochemical analysis during the 20th century.

It is necessary for those using this book to have some fundamental understanding of the basics of rock engineering. In this chapter, the basics will be explained in a simplified manner while the formal scientific treatment can be found in Appendix A. Some mathematics have to be used, but the more complex equations will be avoided. Another important element of the chapter is to define some of the terms that are used in the rest of the book. To avoid confusion later, it is necessary to provide this material first.

Geophysical methods play a vital role in exploring both the Earth’s surface and its subsurface, addressing complex challenges across the lithosphere, atmosphere, hydrosphere, and cryosphere. Recent advancements in observational systems and computational techniques have significantly enhanced the effectiveness of these methods. Nonetheless, geoscientists continue to face the challenge of accurately detecting deep‑seated structures by estimating the physical parameters of different subsurface layers.

This book has been written for those studying petroleum geology or engineering, for whom the role of the petrophysicist can become a lucrative and satisfying career. The handbook will be equally useful to students and practioners of environmental science and hydrogeology, where the understanding of groundwater flow is an important part of their technical remit.

At a time when the DNA of Neanderthal Man has been sequenced and Jurassic World hints at possible future breakthroughs, however improbable, fossils have an undoubtedly high profile. Collecting fossils is a popular hobby. There is a wealth of helpful literature and websites which will help you to put an accurate name on your latest find, and to identify the various component parts of the skeleton.

Laboratory Manual in Physical Geology is the most widely adopted, user-friendly manual available for teaching laboratories in introductory geology and geoscience. The manual has been produced under the auspices of the American Geological Institute (AG1) and the National Association of Geoscience Teachers (NAGT). It is backed up by an Internet site, GeoTools (ruler, protractor, UTM grids, sediment grain size scale, etc.), Instructor Resource Guide, Instructor Transparency Set, and an Instructor Resource Center (IRC) on CD-ROM.