This site describes how and when 100-year floods occur. It states that flood designations are based on statistical averages, not on the number of years between big floods. It also suggests that it would make more sense to refer to 100-year floods as 1-in-100 chance floods. This resource is a United States Geological Survey (USGS) Fact Sheet. It can be used in teaching quantitative skills.
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This USGS site explains what an aquifer is and defines the different types of aquifers based on six principal lithologies; sandstone, carbonate, sandstone-carbonate, igneous and metamorphic, sand and gravel, and other rock types. The site features maps and descriptions of the major aquifers in the United States as well as general information about groundwater occurrence and quality. The site also provides links to additional maps and data about specific aquifers across the nation.
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 website features multiple links to geologic resources relating to the Columbia River Plateau and Columbia River Basalt Group. The types of resources available include background information, special items of interest, maps, graphics, images, and educational outreach for multiple levels of experience.
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.
This resource contains an organized database of resources that provide geoscience data and interpretations to the Federal Land Management Agencies (FLMA) that are basic to sound policy and land-stewardship practices. U.S. Forest Service (USFS) National Forest and Bureau of Land Management (BLM) Resource Area Management Plans for the Headwaters Province are in revision, with completion dates from 1999-2003. USFS Regions 1 and 4 have made National Priority Requests for Mineral Resources Program (MRP) to provide interim products that help them meet their planning cycles. MRP is to provide geologic maps and topical studies to meet longer range goals of integrating geoscience into decision making. This project will emphasize development of digital geoscience data, GIS analyses, and interpretations to ensure that data is available for GIS-based science integration and planning.
This USGS fact sheet summarizes the occurrence of Balkan Endemic Nephropathy, a serious kidney disease that occurs only in tributary valleys of the Danube River in Romania, Bulgaria, and the former Yugoslavia. There is a close correspondence between the location of affected villages and the occurrence of local coal deposits.
This USGS report provides information about the effects of coal combustion on human health. It explains the hazards associated with emissions from both large-scale coal burning electrical plants and domestic cook stoves used in developing nations. In particular, the report discusses specific instances of disease related to the emission of arsenic, fluorine, selenium, thorium, uranium, and polycyclic aromatic hydrocarbons released by burning low-grade coal in poorly vented cook stoves in China.
This website is a cooperative research project between the U.S. Geological Survey (USGS), NASA, the U.S. Army Corps of Engineers, and the University of New Orleans. The goal of the project is to investigate coastal change that occurred as a result of Hurricane Katrina. The site includes aerial video, still photography, and laser altimetry surveys of post-storm beach conditions that were collected August 31 and September 1, 2005 for comparison with earlier data. The comparison data can be used to refine predictive models of coastal impacts from severe storms and aid in disaster recovery and erosion mitigation.
This site is a report presented as an abridged guide for laboratory technicians and students interested in X-ray powder diffraction methodology. Also included, in condensed form, are the principles of diffractometry and descriptions of clay mineralogy, plus many preparatory and interpretive procedures.
This site examines how we have used land since the 1700s and how the land has changed. Topics include population settlement and farmland, urban sprawl and soil resources, flora species, urbanization in the Baltimore-Washington corridor, landcover changes in the Great Lakes region, vegetation along the upper Mississippi River, biodiversity in the Yellowstone ecosystem, and landscape changes in the Southwest.
Louisiana’s Lake Pontchartrain Basin is home to 1.5 million people and an estuary ecosystem with enormous biodiversity. Activities in the educator’s guide help students in grades 5-12 gain an understanding and appreciation of the Basin and teaches them the skills to identify environmental concerns, make changes, and solve problems.
This USGS site provides access to data sets collected by the National Water-Quality Assessment Program. It features fact sheets, reports, bibliographies, additional data sets and links to other resources about nutrients in streams, rivers and aquifers of the United States. The site briefly explains what nutrients are, how they are used in the agricultural industry, how they react chemically in the environment, some of the transport processes that introduce them to surface and groundwater, and why excessive nutrients create water quality problems.
This handbook provides information about the threat posed by earthquakes in the San Francisco Bay region and explains how you can prepare for, survive, and recover from these inevitable events. If you live or work in the region, you need to know why you should be concerned with earthquakes, what you can expect during and after a quake, and what you need to do beforehand to be safe and reduce damage.
This site tells why the April 18, 1906, earthquake along the San Andreas Fault was one of the most significant earthquakes of all time. See photos, eyewitness accounts, the 1906 seismogram, and casualty and damage statistics. Learn about the flurry of scientific investigation unleashed by the quake and the advances that followed.
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.
- Material Type:
- U.S. Geological Survey
- Anna B. Wilson
- Arthur A. Bookstrom
- Bradley S. Van Gosen
- David E. Boleneus
- Gregory N. Green
- Helen Z. Kayser
- J. Douglas Causey
- Jeremy C. Larsen
- Karl V. Evans
- Kenneth C. Assmus
- Mary H. Carlson
- Michael L. Zientek
- Pamela D. Derkey
- Robert J. Miller
- Thomas P. Frost
- William N. Kelley
- Date Added:
This USGS report focuses on Cretaceous rocks in Montana with respect to natural gas and coalbed methane. The study includes the stratigraphy from the top of the Mowry Shale to the base of the Judith River Formation. The project integrates geologic, structural, hydrologic and engineering studies with known and new geochemical data on the gas and co-produced water. The report also facilitates an understanding of the controls on the spatial distribution of potential gas accumulations. Figures, tables, cross-sections and maps can be accessed in PDF format from this location.
The principal purpose of this study guide is to provide a broad selection of study materials that comprise a beginning course in ground-water hydrology. These study materials consist primarily of notes and exercises. The notes are designed to emphasize ideas and to clarify technical points that commonly cause difficulty and confusion to inexperienced hydrologists and may not receive adequate treatment in standard textbooks. Some of the exercises are more extensive than those usually found in textbooks to provide an additional level of detail and to focus on concepts that we consider to be particularly important. Detailed answers to exercises with explanatory comments are available in a companion publication. The most important and unique technical feature of this course is the emphasis on the concept of a ground-water system. Generally, this concept is first developed extensively in a more advanced rather than a beginning course in ground-water hydrology.
This table provides a summary of notable events at Mount Rainier. Events include lahars, bomb-bearing flows, block and ash flows, pyroclastic surges, tephra, lava flows, debris flows, geothermal melting of the glacier, and avalanches. The events range in age from older than 8,750 years to the late 1960s. The table is provided by the USGS Cascades Volcano Observatory, which gathered most of the information from Sedimentology, Behavior, and Hazards of Debris Flows at Mount Rainier, Washington: Geological Survey Professional Paper 1547 by Scott et al., 1995. The table can be used to teach recurrence intervals.
The USGS has developed a national inventory of significant topographic changes based on seamless multitemporal elevation data and land cover data. The National Elevation Dataset (NED) and the Shuttle Radar Topography Mission (SRTM) data form a unique pair of seamless elevation datasets that can be used to detect and analyze 20th century topographic surface changes in the United States.
The need for more comprehensive information on the nature and extent of recent human geomorphic activity led to a spatial emphasis for the first ever accounting of topographic change across the United States. Historical NED data values were subtracted from the recently collected SRTM data to determine significant topographic changes. The National Land Cover Dataset (NLCD) provided land cover information at a 30-meter resolution that matched the NED and SRTM data.
The primary types of topographic changes resulting from human geomorphic activity include surface mining, road construction, urban development, dam construction, and landfills.