This five day field trip is a general overview of the geology and tectonic history of central Colorado and of the geology of seven famous mining districts. Some of these mining districts had their most productive years in the latter decades of the 19th century, whereas others reached their peak production more recently. At present mining activity in some of them has ceased. In others it is at low levels compared to earlier years. The regional geology and the road log are compiled from numerous sources. The principal ones are field trip guides by Tweto (1978), Reed and others (1988), Lipman (in press) and unpublished field guides of the Colorado Scientific Society and the Society of Economic Geologists. Figure 1 shows the principal geographic features along the route of the trip. <...>

Day 1 questa caldera and associated porphyry molybdenum Mineralization, latir volcanic field, sangre de Cristo mountains, and rio grande rift
Day 2 san juan mountains, southeast caldera complex and Acid-sulfate epithermal mineralization at summitville
Day 3 central san juan caldera cluster and adularia-sericite Epithermal mineralization at creede
Day 4 western san juan caldera complex and multistage mineralization around the lake city caldera

Duane Allan Smith has been called many things, but no one can deny he is Colorado’s most prolific historian, surpassing even the late, great LeRoy Hafen. The Trail of Gold and Silver is Smith’s fiftieth book. The University Press of Colorado’s Timberline Books series, which features the best current work on Colorado as well as classic reprints, proudly presents this master historian’s survey of 150 years of Colorado gold and silver mining. <...>

Recent quantitative studies of gneisses in the Laramie Range by Newhouse and Hagner (1947) have resulted in the idea that structure of the host rock is a dominant factor controlling the composition of gneisses and schists. The Sherman granite, which is exposed in the southern part of the Laramie Range (Fig. 1), was selected for a quantitative study for three reasons: (1) a similar study had been made by Newhouse and Hagner on associated gneissic rocks which made it possible to correlate and compare results; {'d) most of the geologic contacts were mapioed previously, and thus nearly all of the field time could be devoted to a study of the granite; and (3) the area is of batholithic dimensions and is readily accessible. The problem was to determine whether any relationship existed between structure and composition of the granite, to explain the significance of any correlation or lack of correlation discovered, and to determine the relation of the Sherman granite to the Raggedtop gneisses studied by Newhouse and Hagner. <...>

1. Выявление коренного источника россыпного золота района Ханс-Пик (штат Колорадо) с помощью изотопов свинца и других данных

2. Интерпретация содержания гидроксильных групп в биотитах и мусковитах

3. Выяснение механизма повреждения синтетических содалитов с помощью электронной микроскопии

Since fossil vertebrates were first discovered at Porcupine Cave on the rim of South Park, Colorado, in 1981, the site has become the world’s most important source of information about animals that lived in the high elevations of North America in the middle part of the ice ages, between approximately one million and 600,000 years ago. Beginning in 1985, teams of scientists and volunteers from three major research institutions —the Carnegie Museum of Natural History, the Denver Museum of Nature and Science, and the University of California Museum of Paleontology—spent some 15 field seasons excavating and studying tens of thousands of fossil specimens that have opened a window onto past evolutionary and ecological adjustments. This window into the past allows us to visualize how ongoing global change could affect our living communities. This book reports the results of nearly two decades of research and has been written to appeal to three overlapping audiences