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Thermal evolution of sedimentary basins in Alaska
The complex tectonic collage of Alaska is reflected in the conjunction of rocks of widely varying thermal maturity. Indicators of the level of thermal maturity of rocks exposed at the surface, such as vitrinite reflectance and conodont color alteration index, can help constrain the tectonic evolution of such complex regions and, when combined with petrographic, modern heat flow, thermogeochronologic, and isotopic data, allow for the detailed evaluation of a region?s burial and uplift history. We have collected and assembled nearly 10,000 vitrinite-reflectance and conodont-color-alteration index values from the literature, previous U.S. Geological Survey investigations, and our own studies in Alaska. This database allows for the first synthesis of thermal maturity on a broadly regional scale. Post-accretionary sedimentary basins in Alaska show wide variability in terms of thermal maturity. The Tertiary interior basins, as well as some of the forearc and backarc basins associated with the Aleutian Arc, are presently at their greatest depth of burial, with immature rocks exposed at the surface. Other basins, such as some backarc basins on the Alaska Peninsula, show higher thermal maturities, indicating modest uplift, perhaps in conjunction with higher geothermal gradients related to the arc itself. Cretaceous ?flysch? basins, such as the Yukon-Koyukuk basin, are at much higher thermal maturity, reflecting great amounts of uplift perhaps associated with compressional regimes generated through terrane accretion. Many sedimentary basins in Alaska, such as the Yukon-Koyukuk and Colville basins, show higher thermal maturity at basin margins, perhaps reflecting greater uplift of the margins in response to isostatic unloading, owing to erosion of the hinterland adjacent to the basin or to compressional stresses adjacent to basin margins.
Database for geologic maps of pyroclastic-flow and related deposits of the 1980 eruptions of Mount St. Helens, Washington
This publication releases digital versions of the geologic maps in U.S. Geological Survey Miscellaneous Investigations Map 1950 (USGS I-1950), “Geologic maps of pyroclastic-flow and related deposits of the 1980 eruptions of Mount St. Helens, Washington” (Kuntz, Rowley, and MacLeod, 1990) ( https://pubs.er.usgs.gov/publication/i1950 ). The 1980 Mount St. Helens eruptions on May 18, May 25, June 12, July 22, August 7, and October 16–18 produced pyroclastic-flow and related deposits. The distribution and morphology of these deposits, as determined from extensive field studies and examination of vertical aerial photographs, are shown on four maps in I-1950 (maps A–D) on two map sheets. Map A shows the May 18, May 25, and June 12 deposits; map B shows the July 22 deposits; map C shows the August 7 deposits; and map D shows the October 16–18 deposits. No digital geospatial versions of the geologic data were made available at the time of publication of the original maps. This data release consists of attributed vector features, data tables, and the cropped and georeferenced scans from which the features were digitized, in order to enable visualization and analysis of these data in GIS software. This data release enables users to digitally re-create the maps and description of map units of USGS I-1950; map sheet 1 includes text sections (Introduction, Physiography of Mount St. Helens at the time of the 1980 eruptions, Processes of the 1980 eruptions, Deposits of the 1980 eruptions, Limitations of the maps, Preparation of the maps, and References cited) and associated tables and figures that are not included in this data release.
Environmental Database For Water-Quality Data for the Penobscot River, Maine: Design Documentation and User Guide
An environmental database was developed to store water-quality data collected during the 1999 U.S. Geological Survey investigation of the occurrence and distribution of dioxins, furans, and PCBs in the riverbed sediment and fish tissue in the Penobscot River in Maine. The database can be used to store a wide range of detailed information and to perform complex queries on the data it contains. The database also could be used to store data from other historical and any future environmental studies conducted on the Penobscot River and surrounding regions.
High-resolution boomer seismic-reflection profiles of the shelf off southern California from cruise A-1-00-SC: Santa Monica Bay to San Diego
High-resolution boomer data were collected in the California Continental Borderland as part of the southern California Earthquake Hazards Task of the Southern California Coastal and Marine Geology Regional Investigations Project. During the period from 1997 to 2002, five data-acquisition cruises collected seismic-reflection data using several different systems from offshore Santa Barbara, California, south to the Exclusive Economic Zone boundary with Mexico. A key mission of this project was to map late Quaternary deformation in addition to improving our understanding of which offshore fault zones might have potential to damage highly populated areas of southern California. State regulations concerning the use of seismic-reflection equipment within three miles of the coastline precluded the routine gathering of high-resolution multichannel data in that swath adjacent to the coast. Boomer seismic-reflection data, however, can be obtained within the state 3-mile limit provided the operation receives authorization from the California State Lands Commission. The Geopulse boomer data accessible through this report were collected on the cruise A-1-00-SC, which was the only survey where we requested permission to work inside the 3-mile limit of the State of California. These data are critical to discovering connections between onshore and offshore faults, the overall lengths of which are related to the potential size of an earthquake that might be generated along them. The 2000 survey was designed to fill the gap between onshore data and reflection data obtained in deeper water on previous cruises as well as data anticipated from future surveys. This report includes trackline maps showing the location of the data, as well as both digital data files (SEG-Y) and images of all of the profiles.
Characteristics of suspended and streambed sediment within constructed chutes and the main channel at Upper Hamburg and Glovers Point Bends, Missouri River, Nebraska, 2008
The U.S. Army Corps of Engineers, Omaha District, as part of the Missouri River Bank Stabilization and Navigation Mitigation Project, has constructed 17 off-channel chutes along the channelized Missouri River, downstream from Sioux City, Iowa, to increase habitat diversity. To better understand characteristics of suspended and streambed sediment within these constructed chutes, the U.S. Geological Survey investigated specific aspects of chute design and function in relation to sediment characteristics including: (1) effects of inlet structures; (2) changes occurring between the inlet and the outlet of a chute; (3) effects of chutes on sediment characteristics in the main channel; and (4) differences in chute dynamics between sampled chutes. Two chutes differing in design, location, and dynamics were studied, Upper Hamburg Bend near Nebraska City, Nebr., and Glovers Point Bend near Winnebago, Nebr. Each site was characterized using five or more sampling transects (two in the chute and three to four in the main channel) designed to bracket sediment exchanges between chutes and the main channel. A sixth transect was included at the Upper Hamburg Bend study site to account for the effects of a nontarget chute having its inlet midway between the inlet and outlet of the primary chute. Representative samples of suspended and streambed sediment were collected at each transect, along with measurements of turbidity and streamflow, between June and November 2008. Four sets of samples were collected at the Glovers Point Bend study site and five sample sets were collected from the Upper Hamburg Bend study site. Results from paired t-tests and standard t-tests indicated that the inlet structure design, passing inflow only from the top of the main-channel water column, reduced the supply of coarse-grained suspended sediment entering the chutes. Statistical comparisons did not indicate differences between the inlet and outlet of either chute; however, anecdotal evidence of recent bank erosion and in-channel deposition was observed in both chutes during the study period. Chutes had little effect on Missouri River main-channel sediment characteristics, which could be explained by the much greater streamflow of the main channel. Between-chute comparisons showed no significant differences in the suspended-sediment characteristics; however, the Upper Hamburg Bend chute had a coarser streambed, wider channel, and much greater streamflow than did the Glovers Point Bend chute.
Soils Data Related to the 1999 FROSTFIRE Burn
This report describes the sample collection and processing for U.S. Geological Survey efforts at FROSTFIRE, an experimental burn that occurred in Alaska in 1999. Data regarding carbon, water, and energy dynamics pre-fire, during, and post-fire were obtained in this landscape-scale prescribed burn. U.S. Geological Survey investigators measured changes in the stocks of carbon (C), nitrogen (N), mercury (Hg), and other components in pre- and post-burn soils of this watershed.
Soils, vegetation, and woody debris data from the 2001 Survey Line fire and a comparable unburned site, Tanana Flats region, Alaska
This report describes the collection and processing methodologies for samples obtained at two sites within Interior Alaska: (1) a location within the 2001 Survey Line burn, and (2) an unburned location, selected as a control. In 2002 and 2004 U.S. Geological Survey investigators measured soil properties including, but not limited to, bulk density, volumetric water content, carbon content, and nitrogen content from samples obtained from these sites. Stand properties, such as tree density, the amount of woody debris, and understory vegetation, were also measured and are presented in this report.
Movements of wild pigs in Louisiana and Mississippi, 2011-13
The prolific breeding capability, behavioral adaptation, and adverse environmental impacts of invasive wild pigs ( Sus scrofa ) have increased efforts towards managing their populations and understanding their movements. Currently, little is known about wild pig populations and movements in Louisiana and Mississippi. From 2011 to 2013, the U.S. Geological Survey investigated spatial and temporal movements of wild pigs in both marsh and nonmarsh physiographic regions. Twenty-one Global Positioning System satellite telemetry tracking collars were installed on adult wild pigs captured with trained dogs and released. Coordinates of their locations were recorded hourly. We collected 16,674 hourly data points including date, time, air temperature, and position during a 3-year study. Solar and lunar attributes, such as sun and moon phases and azimuth angles, were not related significantly to the movements among wild pigs. Movements were significantly correlated negatively with air temperature. Differences in movements between seasons and years were observed. On average, movements of boars were significantly greater than those of sows. Average home range, determined by using a minimum convex polygon as a proxy, was 911 hectares for boars, whereas average home range for sows was 116 hectares. Wild pigs in marsh habitat traveled lesser distances relative to those from more arid, nonmarsh habitats. Overall, results of this study indicate that wild pigs in Louisiana and Mississippi have small home ranges. These small home ranges suggest that natural movements have not been a major factor in the recent broad-scale range expansion observed in this species in the United States.
Insect community responses to climate and weather across elevation gradients in the Sagebrush Steppe, eastern Oregon
Executive Summary In this study, the U.S. Geological Survey investigated the use of insects as bioindicators of climate change in sagebrush steppe shrublands and grasslands in the Upper Columbia Basin. The research was conducted in the Stinkingwater and Pueblo mountain ranges in eastern Oregon on lands administered by the Bureau of Land Management. We used a “space-for-time” sampling design that related insect communities to climate and weather along elevation gradients. We analyzed our insect dataset at three levels of organization: (1) whole-community, (2) feeding guilds (detritivores, herbivores, nectarivores, parasites, and predators), and (3) orders within nectarivores (i.e., pollinators). We captured 59,517 insects from 176 families and 10 orders at the Pueblo Mountains study area and 112,305 insects from 185 families and 11 orders at the Stinkingwater Mountains study area in 2012 and 2013. Of all the individuals captured at the Stinkingwater Mountains study area, 77,688 were from the family Cecidomyiidae (Diptera, gall gnats). We found that the composition of insect communities was associated with variability in long-term (30-yr) temperature and interannual fluctuations in temperature. We found that captures of certain fly, bee, moth, and butterfly pollinators were more strongly associated with some climate and vegetation variables than others. We found that timing of emergence, as measured by first detection of families, was associated with elevation. When analyzed by feeding guilds, we found that all guilds emerged later at high elevations except for detritivores, which emerged earlier at high elevations. The abundance of most taxa varied through time, mostly in response to temperature and precipitation. Of the pollinators, bees (particularly, Halictidae and Megachilidae) peaked in abundance in late June and early July, whereas butterflies and moths peaked in August. Flies peaked in abundance in July. Overall, our interpretation of these patterns is that insect communities respond positively and negatively to weather and local vegetation more than to long-term climate. Given increasing variability in weather and high probability of extreme weather events, insect communities in sagebrush steppe also may experience considerable fluctuations in composition and abundance, as well as phenology. These findings have implications for many ecosystem services, including pollination, decomposition, and food resources for predatory birds and other vertebrates.
Fluorospar Investigations: Preliminary Report on the Geology of the Columbia Mine Area, Crittenden County, Kentucky
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Missouri River basin. Geologic mapping and mineral resources investigations, North Fork of Solomon River sub-basin. Construction materials in Phillips County, Kansas
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Origin of manganese deposits of Busuanga Island, Philippines
The manganese deposits of Busuanga Island, Palawan, are tabular and broadly lenticular bodies which lie conformably within a thick sequence of deformed abort beds. The purpose of this study is to determine the probable mode of origin of the deposits. Similar deposits in other parts of the world have been described by others as products of several different genetic processes. Field and laboratory methods of research were employed in the course of the investigation. Detailed geologic mapping was done on the surface and underground, and many samples of rocks and ores were obtained. Later, intensive study of samples from four typical deposits and from the rooks in the surrounding areas was undertaken, using a variety of laboratory techniques. Microscopic study of thin sections and polished surfaces was supplemented by X-ray and chemical work. More than one hundred X-ray diffraction powder photographs were made to identify minerals, and qualitative chemical studies were made of a number of aamples by use of the X-ray spectrograph. In addition, quantitative chemical analyses were made of certain samples. Finally, published accounts of the occurrence and geological behavior of manganese and silica were consulted to aid in interpretation of the data at hand. Oherty layers in the manganese deposits are lithologically similar to the chart wallrooks and country rook beds. Radiolarian fossils are common in the chart and are also found in some ore specimens. Manganese content of the wallrocks and the country rock beds, however, in essentially nil. The manganese deposits contain mostly psilomelane-type oxides in their near-surface parts, and in the deepest mines this ore grades downward into siliceous protore. In three of the deposits studied, the protore consists mainly of braanite and quartz; in the fourth deposit, hausmannite and the silicate alleghatvite make up the milk of the protore. Some of the protoro is massive, but cherty stones are commonly well layered parallel to the wall rock structure. Grain size is very small, but, like the silica in the chert beds, becomes relatively coarse where the rocks are much deformed. No evidence of large-scale replacement or cross-cutting veins is found in the protores. It is concluded that the original manganiferous deposits were largely non-clastic or oolloidal marine sediments laid down in a reducing environment. The protorea were developed from these beds by processes of diagenesis and low-grade regional metamorphism. The protores were in turn altered to black oxide ore by near-surface agencies during the present erosion cycle. Particular interest is attached to the occurrence of alleghanyite and traces of pyroxmangite and hubnerite(?) in the protorea.
Summary of hydrologic investigations by the United States Geological Survey at White Sands Missile Range, New Mexico
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Preliminary report on the geology and field petrology at the Apollo 17 landing site
No abstract available.
Ground-water quality in selected areas serviced by septic tanks, Dade County, Florida
During 1971-74, the U.S. Geological Survey investigated the chemical, physical, bacteriological, and virological characteristics of the ground water in five selected areas serviced by septic tanks in Dade County, Florida. Periodic water samples were collected from multiple-depth groups of monitor wells ranging in depth from 10 to 60 ft at each of the five areas. Analyses of ground water from base-line water-quality wells in inland areas remote from urban development indicated that the ground water is naturally high in organic nitrogen, ammonia, organic carbon and chemical oxygen demand. Some enrichment of ground water with sodium provided a possible key to differentiating septic-tank effluent from other urban ground-water contaminant sources. High ammonia nitrogen, phosphorus, and the repetitive detection of fecal coliform bacteria were characteristic of two 10-foot monitor wells that consistently indicated the presence of septic-tank effluent in ground water. Dispersion, dilution, and various chemical processes have presumably prevented accumulation of septic-tank effluent at depths greater than 20 ft, as indicated by the 65 types of water analyses used in the investigation. Fecal coliform bacteria were present on one or two occasions in many monitor wells but the highest concentration, 1,600 colonies/100 ml, was related to storm-water infiltration rather than septic-tank discharge. Areal variations in the composition and the hydraulic conductivity of the sand and limestone aquifer had the most noticeable influence on the overall ground-water quality. The ground water in the more permeable limestone in south Dade County near Homestead contained low concentrations of septic-tank related constituents, but higher concentrations of dissolved sulfate and nitrate. The ground water in north Dade County, where the aquifer is less permeable, contained the highest dissolved iron, manganese, COD, and organic carbon.