The purpose of this communication is to summarize and make available a large amount of data on the content of major and minor elements in the host rocks and ores of the Carlin gold deposit and to show the changes in the abundance of these elements as a result of hydrothermal mineralization and subsequent oxidation. Other aspects of the study of minor elements in the Carlin deposit, including the correlation between elements in various types of ore and the influence of geologic features on spatial distribution, will be presented in a later paper. The Carlin gold deposit is located about 33 miles northwest of Elko, Nevada (Fig. 1).

The deposit is characterized by large disseminated replacement-type ore bodies in the upper beds of the Silurian Roberts Mountains Formation. Several of these ore bodies are currently exposed in the West, Main, and East Pit areas of the mine. Although detailed information on the depth of gold deposition and the geometry of individual ore bodies cannot be disclosed (by agreement with Newmont Mining Corporation), the host rocks have been hydro-thermally altered in some parts of the deposit to a depth of 800+ feet. Small amounts of gold are scattered throughout this depth, and larger amounts, concentrated in several zones, make up the ore bodies.

The host rocks for the ore bodies are dark- to medium-gray, thin-bedded, siliceous, argillaceous, dolomitic limestones. Mineralogically the rocks are made up of large and widely varying amounts of calcite, dolomite, illite, and quartz, plus minor kaolin, montmorillonite( ?), chlorite, K-feldspar, plagioclase, pyrite, zircon, barite, rutile, sphene, and carbonaceous materials.    Complete chemical analyses of the fresh carbonate rocks are given by Hausen (1967), Hausen and Kerr (1968), and Radtke and Scheiner (1970).

A wide diversity of techniques is now available to help constrain the timing and duration of fluid flow events and fluid-rock interactions in sedimentary basins. Dating methods in rocks traditionally focus on the use of minerals that contain radiogenic isotopes (U-Pb, Pb-Pb, K-Ar, Rb-Sr in particular). I do not intend to dwell on this approach as it is covered adequately elsewhere (e.g. Faure 1986), but it is worthwhile emphasizing that certain phases that are commonly precipitated during diagenesis in sedimentary basins are suitable for such techniques (see below). The range of techniques summarized below were mostly presented in a Queen's University Geofluids Group International Seminar on Dating of Fluid Flow, incorporated within the Geofluids II conference held at Belfast in March 1997. <...>

The last decade has witnessed the expansion of field work and the recovery of many important new fossil vertebrates from a number of areas in the Rocky Mountain Interior. This has resulted in (among other things) discovery of many previously unknown taxa and of much better preserved specimens of known forms, significant geographic and temporal range extensions, the development of greater temporal resolution and sampling density for many taxa (leading to much more precise biochronology), and the creation and applicaton of models for examining faunal relations and evolutionary patterns. When the opportunity for this symposium arose, we were faced with the dilemma of how to incorporate as much of this new information as possible, yet limit the resulting monograph to manageable proportions. We decided to confine the subject matter geographically and temporally, to a region and a time span with which we are most familiar and within which much of the exciting new research is now being conducted—the latest Cretaceous and early Tertiary of the northern Rocky Mountain region. This volume is derived from papers presented at that symposium on May 2,1987, at the annual regional meeting of the Rocky Mountain Section of the Geological Society of America, held at the University of Colorado in Boulder <...>

A typical debris flow is a torrential flow of a mixture of water, mud and debris that suddenly pushes ahead with a vanguard of huge, jostling and roaring boulders. It is certainly a very fearful phenomenon that causes disasters, but it is also truly a wonder of nature exciting the curiosity of researchers as to how such a phenomenon can arise. The phenomena themselves had been recognized since ancient times in Japan and given various mnemonic names to make people aware of the dangers. Although there were several detailed witness records around in 1965 when I began working for the Disaster Prevention Research Institute of Kyoto University (hereafter called DPRI), the characteristics and mechanisms of debris flows were still vague, and it was called a ‘phantasmal disaster’.