This resource is a part of the USGS document entitled "Preliminary Compilation of Descriptive Geoenvironmental Mineral Deposit Models". This chapter of the document describes gold, silver and tellurium vein deposits. Topics include a summary of relevant geologic, environmental, and geophysical information, geologic factors that influence potential environmental effects, and environmental signatures.

This resource presents a brief overview the glaciation that created the Bering Land Bridge National Preserve. Links are provided to maps of the region, information about coastal geology, glaciers, volcanoes, mountains, and recommended reading.

This USGS site contains information on the geology units, topography, and precipitation rates of the Black Hills as it relates to the hydrology. Included is a map defining the study area, precipitation graphs, a stratigraphic column, a map denoting the distribution of hydrogeologic units, a geologic cross section, and a photo of the hydrogeologic setting. Links to an introduction to this study, objectives, products, references, and digital map services are also available through this site.

In this activity students study some applications of knowing the density of rocks. One set of applications involves the stress, strength, and factor of safety for a rock roof resting on one or more columns in an underground room. A second set of applications involves the normal and shear stresses, cohesion force, and inclination angle for a slab of rock resting on an inclined surface. Students recreate spreadsheets shown in a Powerpoint module with formulas that answer various pieces of an overall question. This module is the fourth in a series of six that examines the density of planets and rocks, and was designed for an undergraduate class where students are asked to look at geological questions mathematically and may spend more time on the math than on the geology. This site includes teaching notes and tips, and links to teaching materials and additional resources.

This USGS document provides a summary of characteristics of gold-silver-tellurium vein deposits. The data includes the geological environment of the deposits such as rock types, textures, age ranges, depositional environment, tectonic setting, and associated deposit types. The deposit description includes information about mineralogy, texture/structure, alteration, ore controls, and weathering. Also included is a list of examples where these vein deposits are found.

In this activity students devise a way of graphically plotting the density variations vs. depth in the Earth. They recreate spreadsheets, shown in the Powerpoint module, with formulas that answer various pieces of the overall question. This module is the sixth in a series of six that examine the density of planets and rocks, and was designed for an undergraduate class where students are asked to look at geological questions mathematically and may spend more time on the math than on the geology. The site includes teaching notes and tips, and links to teaching materials and additional resources.

In this activity students explore the combination of densities and shell thicknesses that produce an aggregate density of the Earth of 5.5 g/cm3. They recreate spreadsheets shown in the Powerpoint module with formulas that answer various pieces of the overall question. This is the fifth module in a series of six that examine the density of planets and rocks, and was designed for an undergraduate class where students are asked to look at geological questions mathematically and may spend more time on the math than on the geology. The site includes teaching notes and tips, and links to teaching materials and additional resources.

In this activity students calculate the pressure at the depth of compensation along a cross section of North America. They recreate spreadsheets, shown in the Powerpoint module, with formulas that answer various pieces of the overall question. This module is the third in a set of three dealing with isostasy, and was designed for an undergraduate class where students are asked to look at geological questions mathematically and may spend more time on the math than on the geology. The site includes teaching notes and tips, and links to teaching materials and additional resources.

This activity lays the mathematical underpinning for studying isostasy in the earth. Students numerically and then analytically determine the relations governing the depth of compensation in a variety of situations including a block of ice floating in water. They recreate spreadsheets shown in a Powerpoint module with formulas that answer various pieces of the overall question. This module is the first in a set of three exploring isostasy, and was designed for an undergraduate class where students are asked to look at geological questions mathematically and may spend more time on the math than on the geology. The site includes teaching notes and tips, and links to teaching materials and additional resources.

This interactive mapping system is one component of the U. S. Geological Survey's Framework Studies and Assessment of the Gulf Coast Project. This project provides the geologic, geophysical, and geochemical framework for the region. The mapping system displays different aspects of the energy resources which reside in the Gulf of Mexico Basin, one of the major hydrocarbon producing areas of the world.

Mount St. Helens erupted on May 18, 1980, devastating more than 150 square miles of forest in southwestern Washington state. This animation shows Landsat images of the Mount St. Helens area in 1973, 1983, and 2000, illustrating the destruction and regrowth of the forest. The 1983 image clearly shows the new crater on the northern slope where the eruption occurred, the rivers and lakes covered with ash, and the regions of deforestation. The 2000 image, taken twenty years after the eruption, still shows the changed crater, but much of the devastated area is covered by new vegetation growth.

In this activity students determine the sizes of the various planets in the solar system, scaled such that the orbit of Saturn fits on campus. The students also compare the planet sizes, given the scale, to the grain sizes of different sediment types. Students recreate spreadsheets, shown in a Powerpoint module, with formulas that answer various pieces of the overall question. This module is the second in a series of four on the Galilean Solar System, and was designed for an undergraduate class where students are asked to look at geological questions mathematically and may spend more time on the math than on the geology. The site includes teaching notes and tips, and links to teaching materials and additional resources.

This 206-page PDF is a regionally consistent and integrated geologic spatial database for the Northern Rocky Mountains of Montana, Idaho, and eastern Washington. It brings forty-three 1:100,000- to 1:250,000-scale digital geologic maps into a common database format. The regional geologic database features ArcInfo coverage (NR_GEO) that contains spatial data for both lines (contacts, faults, fold axes, dikes, sills, veins, garnet isograd, boundaries) and polygons (geologic units). The database represents the original content of the published maps and provides easily used and consistent content.

The discipline of structural geology studies the architecture of the solid Earth and other planets. Rock deformation patterns are exciting features beacause of their aesthetic beauty and their economic interest to man. Knowledge of the subsurface structure is vital for the success of a variety of engineering and mineral exploration pograms. A thorough understanding of rock structures is essential for strategic planning in the petroleum and mining industry, in construction operations, in waste disposal surveys and for water exploration. Deformation structures in the country rock are important further for locallizing hazard zones, such as potential rockslide masses, ground subsidence, and seismic faults. Research activities concentrate on rock defomation structures in he shallow continental crust.