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Partnerships - Working Together to Build The National Map

Through The National Map, the U.S. Geological Survey (USGS) is working with partners to ensure that current, accurate, and complete base geographic information is available for the Nation. Designed as a network of online digital databases, it provides a consistent geographic data framework for the country and serves as a foundation for integrating, sharing, and using data easily and reliably. It provides public access to high quality geospatial data and information from multiple partners to help inform decisionmaking by resource managers and the public, and to support intergovernmental homeland security and emergency management requirements.

Fact Sheet↗

Earthquake hazard in the New Madrid Seismic Zone remains a concern

There is broad agreement in the scientific community that a continuing concern exists for a major destructive earthquake in the New Madrid seismic zone. Many structures in Memphis, Tenn., St. Louis, Mo., and other communities in the central Mississippi River Valley region are vulnerable and at risk from severe ground shaking. This assessment is based on decades of research on New Madrid earthquakes and related phenomena by dozens of Federal, university, State, and consulting earth scientists. Considerable interest has developed recently from media reports that the New Madrid seismic zone may be shutting down. These reports stem from published research using global positioning system (GPS) instruments with results of geodetic measurements of strain in the Earth's crust. Because of a lack of measurable strain at the surface in some areas of the seismic zone over the past 14 years, arguments have been advanced that there is no buildup of stress at depth within the New Madrid seismic zone and that the zone may no longer pose a significant hazard. As part of the consensus-building process used to develop the national seismic hazard maps, the U.S. Geological Survey (USGS) convened a workshop of experts in 2006 to evaluate the latest findings in earthquake hazards in the Eastern United States. These experts considered the GPS data from New Madrid available at that time that also showed little to no ground movement at the surface. The experts did not find the GPS data to be a convincing reason to lower the assessment of earthquake hazard in the New Madrid region, especially in light of the many other types of data that are used to construct the hazard assessment, several of which are described here.

Arkansas, Illinois, Kentucky, Missouri, Tennessee↗

From ridge to reef—linking erosion and changing watersheds to impacts on the coral reef ecosystems of Hawai‘i and the Pacific Ocean

Coral reef ecosystems are threatened by unprecedented watershed changes in the United States and worldwide. These ecosystems sustain fishing and tourism industries essential to the economic survival of many communities. Sediment, nutrients, and pollutants from watersheds are increasingly transported to coastal waters, where these contaminants damage corals. Although pollution from watersheds is one of many factors threatening coral survival, it is one that local people can have a profound influence on. U.S. Geological Survey scientists are using mapping, monitoring, and computer modeling to better forecast the effects of watershed changes on reef health. Working with communities in Hawai‘i and on other U.S. islands in the Pacific, they are helping to provide the science needed to make informed decisions on watershed and coral reef management.

Hawai'i↗

Water resources of the Lake of the Woods watershed, north-central Minnesota

The Lake of the Woods watershed is an area of about 2,900 square miles (7,500 km), the northern limit of which is part of the boundary between the United States and Canada. Drainage is to Lake of the Woods, either directly or by the Rainy River. The watershed includes about 470 square miles (1,220 km2) of Lake of the Woods, one-third of the lake’s total area. The watershed, a part of the plain of glacial Lake Agassiz, is an area of low relief and slopes generally northward. Details of topography may be obtained from U.S. Geological Survey 7 1/2-minute quadrangle maps, as indexed. Surficial materials consist mainly of peat, lake-washed till, and beach deposits. Extensive wetlands typify much of the watershed. Bedrock is exposed in places near Lake of the Woods and the Rainy River. Except where cleared for cultivation, most of the watershed is covered by coniferous forests. Harvest of forest products, agriculture, and fishing are major economic activities. The 1970 population of the watershed was bout 6,600, concentrated chiefly along the Rainy River and the south shore of Lake of the Woods.

Minnesota↗

Geologic map of the western equatorial region of Mars

The r egional topographic swell centered in the Tharsis Montes and Syria Planum extends over one-third of the map area (U.S. Geological Survey, 1976). Within this high region are the four largest and youngest volcanoes on Mars: Olympus Mons, Arsia Mons, Pavonis Mons, and Ascrae us Mons. The latter three collectively form the large northeast-trending, volcanic mountain chain of the Tharsis Montes. This volcanic chain lies athwart the global highland - lowland boundary that transects the western equatorial region. The boundary, where not covered b young lava flow s, is marked by a gentle, irregular scarp bordered by clusters of low knobby hills. It separates the relatively smooth, flat, spar sely cratered northern plains from the higher, rougher, more densely cratered plateau terrain of the southern highlands . A vast system of canyons, the Valles Marineris , originates in Noctis Labyrinthus , just east of the Tharsis -Sy ria swell, and extends eastward for several thousand kilo meters. Ancient rivers channels appear to have sources in canyons and chaotic terrain north of Valles Ma rineris and in a large fissure at the head of the Mangala V alles. Visible remnants of large circular basins are not as common on Mars as on the Moon, probably because of more active erosion and deeper burial on Mars by eolian and fluvial activity and by widespread volcanism on both the highlands and plains. The youngest and b est preserved impact basin on Mars, lying in the western hemisphere , is more than 1,00 0 km across. It has a broad flat floor ( Argyre Planitia) covered by eolian materials and volcanic flows ; the floor is several kilometers below its encompassing rough mountainous rim.

IMAP↗

Map of surficial deposits and materials in the eastern and central United States (east of 102 degrees West longitude)

This data set contains surficial geologic units in the Eastern and Central United States, as well as a glacial limit line showing the position of maximum glacial advance during various geologic time periods. The geologic units represent surficial deposits and other surface materials that accumulated or formed during the past 2+ million years, such as soils, alluvium, and glacial deposits. These surface materials are referred to collectively by many geologists as regolith, the mantle of fragmented and generally unconsolidated material that overlies the bedrock foundation of a continent. This data set and the printed map produced from it, U.S. Geological Survey (USGS) Geologic Investigation Series I-2789, were based on 31 published maps in the USGS's Quaternary Geologic Atlas of the United States map series (USGS Miscellaneous Investigations Series I-1420). The data were compiled at 1:1,000,000 scale, to be viewed as a digital map at 1:2,000,000 nominal scale and to be printed as a conventional paper map at 1:2,500,000 scale.

IMAP↗

Geologic map and digital database of the Apache Canyon 7.5' quadrangle, Ventura and Kern counties, California

The Apache Canyon 7.5-minute quadrangle is located in southwestern California about 55 km northeast of Santa Barbara and 65 km southwest of Bakersfield. This report presents the results of a geologic mapping investigation of the Apache Canyon quadrangle that was carried out in 1997-1999 as part of the U.S. Geological Survey's Southern California Areal Mapping Project. This quadrangle was chosen for study because it is in an area of complex, incompletely understood Cenozoic stratigraphy and structure of potential importance for regional tectonic interpretations, particularly those involving the San Andreas fault located just northwest of the quadrangle and the Big Pine fault about 10 km to the south. In addition, the quadrangle is notable for its well-exposed sequences of folded Neogene nonmarine strata including the Caliente Formation of Miocene age from which previous workers have collected and described several biostratigraphically significant land-mammal fossil assemblages. During the present study, these strata were mapped in detail throughout the quadrangle to provide an improved framework for possible future paleontologic investigations. The Apache Canyon quadrangle is in the eastern part of the Cuyama 30-minute by 60-minute quadrangle and is largely part of an erosionally dissected terrain known as the Cuyama badlands at the east end of Cuyama Valley. Most of the Apache Canyon quadrangle consists of public lands in the Los Padres National Forest.

California↗

Publications of the Western Earth Surface Processes Team 2000

The Western Earth Surface Processes Team (WESP) of the U.S. Geological Survey (USGS) conducts geologic mapping and related topical earth science studies in the western United States. This work is focused on areas where modern geologic maps and associated earth-science data are needed to address key societal and environmental issues such as ground-water quality, potential geologic hazards, and land-use decisions. Areas of primary emphasis in 2000 included southern California, the San Francisco Bay region, the Pacific Northwest, the Las Vegas urban corridor, and selected National Park lands. The team has its headquarters in Menlo Park, California, and maintains smaller field offices at several other locations in the western United States. The results of research conducted by the WESPT are released to the public as a variety of databases, maps, text reports, and abstracts, both through the internal publication system of the USGS and in diverse external publications such as scientific journals and books. This report lists publications of the WESPT released in 2000 as well as additional 1999 publications that were not included in the previous list (USGS Open-file Report 00-215). Most of the publications listed were authored or coauthored by WESPT staff. The list also includes some publications authored by non-USGS cooperators with the WESPT, as well as some authored by USGS staff outside the WESPT in cooperation with WESPT projects. Several of the publications listed are available on the World Wide Web; for these, URL addresses are provided. Many of these Web publications are USGS open-file reports that contain large digital databases of geologic map and related information.

Open-File Report↗

Publications of Western Earth Surface Processes Team 2001

The Western Earth Surface Processes Team (WESPT) of the U.S. Geological Survey (USGS) conducts geologic mapping and related topical earth-science studies in the Western United States. This work is focused on areas where modern geologic maps and associated earth-science data are needed to address key societal and environmental issues, such as ground-water quality, landslides and other potential geologic hazards, and land-use decisions. Areas of primary emphasis in 2001 included southern California, the San Francisco Bay region, the Pacific Northwest, and the Las Vegas urban corridor. The team has its headquarters in Menlo Park, California, and maintains smaller field offices at several other locations in the Western United States. The results of research conducted by the WESPT are released to the public as a variety of databases, maps, text reports, and abstracts, both through the internal publication system of the USGS and in diverse external publications such as scientific journals and books. This report lists publications of the WESPT released in 2001, as well as additional 1999 and 2000 publications that were not included in the previous list (USGS Open-File Report 00–215 and USGS Open-File Report 01–198). Most of the publications listed were authored or coauthored by WESPT staff. The list also includes some publications authored by non-USGS cooperators with the WESPT, as well as some authored by USGS staff outside the WESPT in cooperation with WESPT projects. Several of the publications listed are available on the World Wide Web; for these, URL addresses are provided. Many of these web publications are USGS Open-File Reports that contain large digital databases of geologic map and related information.

Open-File Report↗

Water-level changes 1977-87, 1987-95, and 1995-2000 in the Chicot and Evangeline Aquifers, Houston-Galveston region, Texas

This report depicts long-term water-level changes in the Chicot and Evangeline aquifers in the Houston-Galveston region. The Houston-Galveston region comprises Harris, Galveston, Fort Bend, Waller, and Montgomery Counties and adjacent parts of Brazoria, Grimes, Walker, San Jacinto, Liberty, and Chambers Counties. The report was prepared in cooperation with the Harris-Galveston Coastal Subsidence District and the Fort Bend Subsidence District. For the Chicot and Evangeline aquifers, maps show approximate water-level changes for the periods 1977 to 1987 (figs. 1 and 4), 1987 to 1995 (figs. 2 and 5), and 1995 to 2000 (figs. 3 and 6). Nineteen seventy-seven was the first year that water levels in a network of wells were measured and water-levelaltitude maps made for the Chicot and Evangeline aquifers. Nineteen eighty-seven, 1995, and 2000 were years in which land-surface altitudes throughout Harris, Galveston, and Fort Bend Counties were releveled using spirit leveling (1987) and Global Positioning Satellite technology (1995 and 2000); thus the selection of those years for the maps. The U.S. Geological Survey (USGS) has published annual reports of water-level altitudes and water-level changes for the Chicot and Evangeline aquifers in the Houston-Galveston region since 1979 and separate similar annual reports for the Fort Bend subregion since 1990. Beginning with 2002, the separate annual reports were combined into one report.

Texas↗

Beowulf Distributed Processing and the United States Geological Survey

Introduction In recent years, the United States Geological Survey's (USGS) National Mapping Discipline (NMD) has expanded its scientific and research activities. Work is being conducted in areas such as emergency response research, scientific visualization, urban prediction, and other simulation activities. Custom-produced digital data have become essential for these types of activities. High-resolution, remotely sensed datasets are also seeing increased use. Unfortunately, the NMD is also finding that it lacks the resources required to perform some of these activities. Many of these projects require large amounts of computer processing resources. Complex urban-prediction simulations, for example, involve large amounts of processor-intensive calculations on large amounts of input data. This project was undertaken to learn and understand the concepts of distributed processing. Experience was needed in developing these types of applications. The idea was that this type of technology could significantly aid the needs of the NMD scientific and research programs. Porting a numerically intensive application currently being used by an NMD science program to run in a distributed fashion would demonstrate the usefulness of this technology. There are several benefits that this type of technology can bring to the USGS's research programs. Projects can be performed that were previously impossible due to a lack of computing resources. Other projects can be performed on a larger scale than previously possible. For example, distributed processing can enable urban dynamics research to perform simulations on larger areas without making huge sacrifices in resolution. The processing can also be done in a more reasonable amount of time than with traditional single-threaded methods (a scaled version of Chester County, Pennsylvania, took about fifty days to finish its first calibration phase with a single-threaded program). This paper has several goals regarding distributed processing technology. It will describe the benefits of the technology. Real data about a distributed application will be presented as an example of the benefits that this technology can bring to USGS scientific programs. Finally, some of the issues with distributed processing that relate to USGS work will be discussed.

Open-File Report↗

Major- and trace-element concentrations in rock samples collected in 2004 from the Taylor Mountains 1:250,000-scale quadrangle, Alaska

The Kuskokwim mineral belt of Bundtzen and Miller (1997) forms an important metallogenic region in southwestern Alaska that has yielded more than 3.22 million ounces of gold and 400,000 ounces of silver. Precious-metal and related deposits in this region associated with Late Cretaceous to early Tertiary igneous complexes extend into the Taylor Mountains 1:250,000-scale quadrangle. The U.S. Geological Survey is conducting geologic mapping and a mineral resource assessment of this area that will provide a better understanding of the geologic framework, regional geochemistry, and may provide targets for mineral exploration and development. During the 2004 field season 137 rock samples were collected for a variety of purposes. The 4 digital files accompanying this report reflect the type of analysis performed and its intended purpose and are available for download as an Excel workbook, comma delimited format (*.csv), dBase 4 files (*.dbf) or as point coverages in ArcInfo interchange format (*.e00). Data values are provided in percent, pct (1gram per 100grams), or parts per million, ppm (1gram per 1,000,000grams) per the column heading in the table. All samples were analyzed for a suite of 42 trace-elements (icp42.*) to provide data for use in geochemical exploration as well as some baseline data. Selected samples were analyzed by additional methods; 104 targeted geochemical exploration samples were analyzed for gold, arsenic, and mercury (auashg.*); 21 of these samples were also analyzed to obtain concentrations of 10 loosely bound metals (icp10.*); 33 rock samples were analyzed for major element oxides to support the regional mapping program (reg.*), of which 28 sedimentary rock samples were also analyzed for total carbon, and carbonate carbon.

Open-File Report↗

Publications of the Western Earth Surface Processes Team 2006

The Western Earth Surface Processes Team (WESPT) of the U.S. Geological Survey (USGS) conducts geologic mapping, earth-surface process investigations, and related topical earth science studies in the western United States. This work is focused on areas where modern geologic maps and associated earth-science data are needed to address key societal and environmental issues such as ground-water quality, landslides and other potential geologic hazards, and land-use decisions. Areas of primary emphasis in 2006 included southern California, the San Francisco Bay region, the Mojave Desert, the Colorado Plateau region of northern Arizona, and the Pacific Northwest. The team has its headquarters in Menlo Park, California, and maintains smaller field offices at several other locations in the western United States. This compilation gives the bibliographical citations for 123 new publications, most of which are available online using the hyperlinks provided.

Open-File Report↗

Seismic hazard of American Samoa and neighboring South Pacific Islands--methods, data, parameters, and results

American Samoa and the neighboring islands of the South Pacific lie near active tectonic-plate boundaries that host many large earthquakes which can result in strong earthquake shaking and tsunamis. To mitigate earthquake risks from future ground shaking, the Federal Emergency Management Agency requested that the U.S. Geological Survey prepare seismic hazard maps that can be applied in building-design criteria. This Open-File Report describes the data, methods, and parameters used to calculate the seismic shaking hazard as well as the output hazard maps, curves, and deaggregation (disaggregation) information needed for building design. Spectral acceleration hazard for 1 Hertz having a 2-percent probability of exceedance on a firm rock site condition (Vs30=760 meters per second) is 0.12 acceleration of gravity (1 second, 1 Hertz) and 0.32 acceleration of gravity (0.2 seconds, 5 Hertz) on American Samoa, 0.72 acceleration of gravity (1 Hertz) and 2.54 acceleration of gravity (5 Hertz) on Tonga, 0.15 acceleration of gravity (1 Hertz) and 0.55 acceleration of gravity (5 Hertz) on Fiji, and 0.89 acceleration of gravity (1 Hertz) and 2.77 acceleration of gravity (5 Hertz) on the Vanuatu Islands.

South Pacific Islands↗

First comprehensive list of non-native species established in three major regions of the United States

Invasive species are a subset of non-native (or alien) species, and knowing what species are non-native to a region is a first step to managing invasive species. People have been compiling non-native and invasive species lists ever since these species started causing harm, yet national non-native species lists are neither universal, nor common. Non-native species lists serve diverse purposes: watch lists for preventing invasions, inventory and monitoring lists for research and modeling, regulatory lists for species control, and nonregulatory lists for raising awareness. This diversity of purpose and the lists’ variation in geographic scope make compiling comprehensive lists of established (or naturalized) species for large regions difficult. However, listing what species are non-native in an area helps measure Essential Biodiversity Variables for invasive species monitoring and mount an effective response to established non-native species. In total, 1,166 authoritative sources were reviewed to compile the first comprehensive non-native species list for three large regions of the United States: Alaska, Hawaii, and the conterminous United States (lower 48 States). The list contains 11,344 unique names: 598 taxa for Alaska, 5,848 taxa for Hawaii, and 6,675 taxa for the conterminous United States. The list is available to the public from U.S. Geological Survey ScienceBase ( https://doi.org/10.5066/P9E5K160 ), and the intent, though not a guarantee, is to update the list as non-native species become established in, or are eliminated from, the United States. The list has been used to annotate non-native species occurrence records in the U.S. Geological Survey all-taxa mapping application, Biodiversity Information Serving Our Nation (BISON, https://bison.usgs.gov ).

Open-File Report↗

Preliminary report on the Nelson and Radovan copper prospects, Nizina district, Alaska

Renewed copper exploration by Alaska Copper Mines, Incorporated, at the Nelson and Radovan prospects, Nizina district, Alaska, led the Geological Survey in 1951 to map in detail the Nelson fault block, and to re-examine the old workings. In addition, two new prospects were studied. The Nelson fault block is cut by many dominantly strike-slip faults of small displacement, and by bedding faults. Slickensided chalcocite shows post-mineral movement, and chalcocite veinlet in a filled solution cavity indicates that some of the chalcocite is secondary, perhaps very recent. Structural relations indicate two overthrust faults cut the block. The Radovan Greenstone prospect shows massive chalcocite, up to 3 feet wide, in a silicified, epidotized fault zone in the Nikolai greenstone. Ore indicated by surface exposures may amount to 450 tons of chalcocite. The Radovan Low-Contact prospect is on a continuation of the same fault approximately 3 miles southwest of the Greenstone prospect, and 150 feet above the contact of the Nikolai greenstone and the overlying Chitistone limestone. Limonite staining is widespread in bedding planes and small faults near the fault zone; mineralization in the fault zone consists of pyrite, chalcocite, bornite, malachite, realgar, orpiment and stibnite. The sulphides in the fault zone, plus the widespread silicification and epidotization indicate a strong zone of hydrothermal activity which merits extensive prospecting.

Open-File Report↗

Report on exploration of the Wadi Yiba copper prospect, Tihamat Ash Sham quadrangle, Kingdom of Saudi Arabia

The first phase of an exploration program at The Wadi Yiba copper prospect consisted of geologic mapping, prospecting, sampling, geophysical surveys, and diamond drilling. Copper mineralization is in a sedimentary rock sequence comprised mostly of siliceous, calcareous, and dolomitic rocks metamorphosed to the greenschist facies. The metasedimentary rocks are overlain and underlain by metavolcanic rocks. They are folded into a tight north-plunging syncline transected by two fault systems. Results from the exploration program indicate that a fault zone which sub-parallels the synclinal axis and cuts siliceous dolomite contains copper mineralization and small amounts of gold and silver. Copper and silver beaming pyroclastic rocks were found in the upper part of the metasedimentary rock sequence. Concentrations of copper mineralization seem to be restricted to particular rock units in the metasedimentary rock sequence. Primary sulfides have not been encountered in the drill holes to date and the results from one drill hole indicate secondary copper sulfide minerals to a vertical depth of 60 meters. Further exploration seems to be warranted and a program is proposed which includes the investigation of other mineral occurrences and geophysical anomalies in the region.

Open-File Report↗

Reconnaissance geology of the Sabkhat Muraysis quadrangle, Kingdom of Saudi Arabia

The Sabkhat Muraysis quadrangle .covers an area of 2843 sq km in the central part of the Kingdom of Saudi Arabia. In the northwestern quarter of the area Precambrian rocks are exposed. They are overlain toward the .south and east by sedimentary formations of Permian and younger age. Four main units of Precambrian .rocks were identified in this area. From oldest to youngest they are: hornblende-biotite granite gneiss; amphibolite and rhyolite of the Halaban Group; graywacke and chlorite-sericite schist of the Bi'r Khountina Group; and biotite-hornblende granite, The hornblende-biotite granite gneiss unit and the biotite-hornblende granite .unit are both poorly exposed and largely covered by veneers of sand, Owing to these factors the boundaries between the granitic, rocks are obscure, Much of what is shown as hornblende-biotite granite gneiss may actually be biotite-hornblende granite. The Halaban Group is represented by an older amphibolite unit called the Umm Mushraha Formation and by a younger rhyolite unit., called the Wadi al Jifr Formation. Layered and msslve components in the Umm Mushraha Formation represent metamorphosed .andesite and graywacke, ,and metamorphosed diorite., gabbro, and pyroxenite. The Wadi al Jifr Formation consists of virtually unmetamorphosed to strongly sheared and metamorphosed rhyolite, rhyolite porphyry, and rhyolite tuff which at many places has been metamorphosed to quartz-sericite schist and biotite-muscovite schist. These schists retain porphyroclasts of blue quartz which also form conspicuous phenocrysts in the unsheared rhyolite. Locally, the sheared rhyolite ha s been hydrothermally altered resulting in the formation of quartz-chlorite-ankerite veins and a sparse impregnation of pyrite. The Bi'r Khountina Group consists of a unit of graywacke and argillite with interbedded andesite that is metamorphosed to chlorite-sericite schist near the contacts of intrusive biottte-hornblende granite. This .unit is-called the Abu Sawarir Formation. It is Intruded by masslve gabbro and pyroxenite. No ancient mines or old prospects were found in the Precambrian part of the quadrangle. Three alteration zones in rhyolite near the northwestern corner of the quadrangle tend to have threshold amounts of molybdenum and tungsten, but they have only background amounts of the base metals and silver. Pyrite is more common in the altered rhyolite than in adjacent rocks. Geological mapping plus and electromagnetic surveys of this area are recommended to explore for sulfide minerals.

Open-File Report↗