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Sample records for 31-33 north central

  1. 22. View looking north on Central Avenue from Washington Street. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. View looking north on Central Avenue from Washington Street. The Stroud Building (with awnings on the second story) is located on the east (right) side of the street near the center of the block. The original Adams Hotel is seen at the right rear of the photograph Circa 1901-1910. Credit ADLAPR. - Stroud Building, 31-33 North Central Avenue, Phoenix, Maricopa County, AZ

  2. 14 CFR 31.33 - Materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Materials. 31.33 Section 31.33 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.33 Materials. (a) The suitability and durability of all materials must be established on the basis of experience or tests. Materials must conform...

  3. 14 CFR 31.33 - Materials.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Materials. 31.33 Section 31.33 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.33 Materials. (a) The suitability and durability of all materials must be established on the basis of experience or tests. Materials must conform...

  4. 14 CFR 31.33 - Materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Materials. 31.33 Section 31.33 Aeronautics... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.33 Materials. (a) The suitability and durability of all materials must be established on the basis of experience or tests. Materials must conform...

  5. North Central Thailand

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This radar image shows the dramatic landscape in the Phang Hoei Range of north central Thailand, about 40 kilometers (25 miles) northeast of the city of Lom Sak. The plateau, shown in green to the left of center, is the area of Phu Kradung National Park. This plateau is a remnant of a once larger plateau, another portion of which is seen along the right side of the image. The plateaus have been dissected by water erosion over thousands of years. Forest areas appear green on the image; agricultural areas and settlements appear as red and blue. North is toward the lower right. The area shown is 38 by 50 kilometers (24 by 31 miles) and is centered at 16.96 degrees north latitude, 101.67 degrees east longitude. Colors are assigned to different radar frequencies and polarizations as follows: red is L-band horizontally transmitted and horizontally received; green is L-band horizontally transmitted and vertically received; blue is C-band horizontally transmitted and vertically received. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar on October 3, 1994, when it flew aboard the space shuttle Endeavour. SIR-C/X-SAR is a joint mission of the U.S./German and Italian space agencies.

    Spaceborne Imaging Radar-C and X-Band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, complemented by aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those changes which are induced by human activity. SIR-C was developed by

  6. 14 CFR 31.33 - Materials.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... design data. (b) Material strength properties must be based on enough tests of material conforming to... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.33 Materials. (a) The suitability and durability of all materials must be established on the basis of experience or tests. Materials must conform...

  7. 14 CFR 31.33 - Materials.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... design data. (b) Material strength properties must be based on enough tests of material conforming to... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.33 Materials. (a) The suitability and durability of all materials must be established on the basis of experience or tests. Materials must conform...

  8. Central portion of north side (front), showing central entry stair ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Central portion of north side (front), showing central entry stair and "Puller Hall" sign - U.S. Naval Base, Pearl Harbor, Enlisted Men's Barracks & Mess Hall, Marine Barracks, Neville Way, Pearl City, Honolulu County, HI

  9. North Dakota to Central Quebec

    NASA Video Gallery

    This video was taken by the crew of Expedition 30 onboard the International Space Station. The sequence of shots was taken January 26, 2012 from 10:04:56 to 10:10:42 GMT, on a pass from North Dakot...

  10. Bilingual Story Times in North Central Washington.

    ERIC Educational Resources Information Center

    Neumiller, Marilyn

    1997-01-01

    Discusses the growth of the Spanish-speaking population served by the North Central Regional Library System (Washington) and the library's response which has included improving Spanish language collections, encouraging staff to learn Spanish, developing bilingual programs for children and families, improving publicity, and using translators. (LRW)

  11. A climatic guide for North Central Oklahoma

    SciTech Connect

    Brown, R.M.

    1991-06-01

    This guide provides some climatological data pertaining to central and north central Oklahoma. The information was derived from standard reference material to reflect what general surface meteorological characteristics exist in that region. It is intended to assist those individuals involved in the implementation of the first ARM site in that locale. A similar guide already exists for the region involved in Kansas entitled, ``One Regional ARM Guide for Climatic Evaluation``. The Oklahoma Kansas area was selected as the first site from the process reported in the ``Identification, Recommendation and Justification of Potential Locales for ARM Sites``.

  12. A climatic guide for North Central Oklahoma

    SciTech Connect

    Brown, R.M.

    1991-06-01

    This guide provides some climatological data pertaining to central and north central Oklahoma. The information was derived from standard reference material to reflect what general surface meteorological characteristics exist in that region. It is intended to assist those individuals involved in the implementation of the first ARM site in that locale. A similar guide already exists for the region involved in Kansas entitled, One Regional ARM Guide for Climatic Evaluation''. The Oklahoma Kansas area was selected as the first site from the process reported in the Identification, Recommendation and Justification of Potential Locales for ARM Sites''.

  13. 1. EXTERIOR OF CENTRAL HEATING STATION, BUILDING 102, LOOKING NORTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. EXTERIOR OF CENTRAL HEATING STATION, BUILDING 102, LOOKING NORTH. - Mill Valley Air Force Station, Central Heating Station, East Ridgecrest Boulevard, Mount Tamalpais, Mill Valley, Marin County, CA

  14. 1. GENERAL VIEW OF NORTH END; CITY OF CHICAGO CENTRAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW OF NORTH END; CITY OF CHICAGO CENTRAL OFFICE BUILDING (1913) SEEN IN CENTER - Chicago River Bascule Bridge, LaSalle Street, Spanning Chicago River at North LaSalle Street, Chicago, Cook County, IL

  15. 27 CFR 31.33 - Retail dealer in beer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Retail dealer in beer. 31... Classified § 31.33 Retail dealer in beer. (a) General. Except as otherwise provided in paragraph (b) of this section, every person who sells or offers for sale beer, but not distilled spirits or wines, to any...

  16. 27 CFR 31.33 - Retail dealer in beer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Retail dealer in beer. 31... Classified § 31.33 Retail dealer in beer. (a) General. Except as otherwise provided in paragraph (b) of this section, every person who sells or offers for sale beer, but not distilled spirits or wines, to any...

  17. 27 CFR 31.33 - Retail dealer in beer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Retail dealer in beer. 31... Classified § 31.33 Retail dealer in beer. (a) General. Except as otherwise provided in paragraph (b) of this section, every person who sells or offers for sale beer, but not distilled spirits or wines, to any...

  18. 27 CFR 31.33 - Retail dealer in beer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Retail dealer in beer. 31... Classified § 31.33 Retail dealer in beer. (a) General. Except as otherwise provided in paragraph (b) of this section, every person who sells or offers for sale beer, but not distilled spirits or wines, to any...

  19. 27 CFR 31.33 - Retail dealer in beer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Retail dealer in beer. 31... Classified § 31.33 Retail dealer in beer. (a) General. Except as otherwise provided in paragraph (b) of this section, every person who sells or offers for sale beer, but not distilled spirits or wines, to any...

  20. Soil indigenous knowledge in North Central Namibia

    NASA Astrophysics Data System (ADS)

    Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus J.

    2016-04-01

    Mapping and classifying soils is part of an important learning process to improve soil management practices, soil quality and increase productivity. In order to assess soil quality improvement related to an ongoing land reform in North-Central Namibia, the characteristics that determine soil quality in the local land use context were determined in this study. To do so, we collated the indigenous soil knowledge in North-Central Namibia where the Ovakwanyama cultivate pearl millet for centuries. Local soil groups are defined mostly based on their productivity potential, which varies depending on the rainfall pattern. The morphological criteria used by the farmers to differentiate the soil groups (colour, consistence) were supported by a conventional analysis of soil physical and chemical properties. Now, they can be used to develop a soil quality assessment toolbox adapted to the regional use. The characteristics of the tool box do not directly indicate soil quality, but refer to local soils groups. The quality of these groups is relatively homogenous at the local scale. Our results show that understanding of indigenous soil knowledge has great potential to improve soil quality assessment with regards to land use. The integration of this knowledge with the conventional soil analysis improves the local meaning of such a "scientific" assessment and thus facilitates dialog between farmers and agronomists, but also scientists working in different regions of the world, but in similar conditions. Overall, the integration of indigenous knowledge in international classification systems (e.g. WRB) as attempted in this study has thus a major potential to improve soil mapping in the local context.

  1. 9. DETAIL, NORTH FRONT, CENTRAL (TALLEST) TOWER, FROM THE NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. DETAIL, NORTH FRONT, CENTRAL (TALLEST) TOWER, FROM THE NORTHWEST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  2. 26. INTERIOR VIEW OF FERRY HOUSE, NORTH CENTRAL BUILDING, FIRST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. INTERIOR VIEW OF FERRY HOUSE, NORTH CENTRAL BUILDING, FIRST LEVEL, LOOKING WEST, MAINTENANCE SHOP - Central Railroad of New Jersey, Jersey City Ferry Terminal, Johnson Avenue at Hudson River, Jersey City, Hudson County, NJ

  3. 27. INTERIOR VIEW OF FERRY HOUSE, NORTH CENTRAL BUILDING, FIRST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. INTERIOR VIEW OF FERRY HOUSE, NORTH CENTRAL BUILDING, FIRST LEVEL, LOOKING EAST, FERRYMEN'S QUARTERS - Central Railroad of New Jersey, Jersey City Ferry Terminal, Johnson Avenue at Hudson River, Jersey City, Hudson County, NJ

  4. 36. VIEW OF PASSENGER WAITING ROOM, FERRY HOUSE, NORTH CENTRAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. VIEW OF PASSENGER WAITING ROOM, FERRY HOUSE, NORTH CENTRAL BUILDING, SECOND LEVEL, LOOKING EAST - Central Railroad of New Jersey, Jersey City Ferry Terminal, Johnson Avenue at Hudson River, Jersey City, Hudson County, NJ

  5. 16. OVERALL VIEW TO THE NORTH OVER THE CENTRAL PART ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. OVERALL VIEW TO THE NORTH OVER THE CENTRAL PART OF THE INTERIOR, RECENTLY USED FOR A BASKETBALL, LOOKING NORTH TOWARDS THE ROLL-UP DOOR. - U.S. Coast Guard Air Station San Francisco, Warehouse, 1020 North Access Road, San Francisco, San Francisco County, CA

  6. LEECHES OF NORTH AMERICA,CENTRAL AMERICA, AND CARIBBEAN SEA

    EPA Science Inventory

    Current(1999)alphabetical listing of the hierarchy, the taxonomy of freshwater leeches (Annelida: Hirudinea) of North America, Central America, islands in the Caribbean Sea, and selected references. The list contains 10 Families, 52 Genera, and 148 Species of leeches.

  7. 19. VIEW WEST; CENTRAL ROOM, NORTH SIDE OF BUILDING, SECOND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. VIEW WEST; CENTRAL ROOM, NORTH SIDE OF BUILDING, SECOND FLOOR. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT

  8. 18. VIEW SOUTHEAST; CENTRAL ROOM, NORTH SIDE, GROUND FLOOR. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. VIEW SOUTHEAST; CENTRAL ROOM, NORTH SIDE, GROUND FLOOR. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT

  9. 22. VIEW WEST; CENTRAL ROOM, NORTH SIDE OF BUILDING, THIRD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. VIEW WEST; CENTRAL ROOM, NORTH SIDE OF BUILDING, THIRD FLOOR. - Naval Undersea Warfare Center, Bowditch Hall, 600 feet east of Smith Street & 350 feet south of Columbia Cove, West bank of Thames River, New London, New London County, CT

  10. ELEVATION OF CENTRAL BAY TO NORTH WING OF EAST ARMORY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ELEVATION OF CENTRAL BAY TO NORTH WING OF EAST ARMORY. - Colt Fire Arms Company, East Armory Building, 36-150 Huyshope Avenue, 17-170 Van Dyke Avenue, 49 Vredendale Avenue, Hartford, Hartford County, CT

  11. 33. Third floor, looking north, elevator and central stair to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. Third floor, looking north, elevator and central stair to the right (original ice manufacturing floor) - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

  12. 8. VIEW LOOKING SOUTH, SHOWING NORTH ENTRANCE HOUSE AND CENTRAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW LOOKING SOUTH, SHOWING NORTH ENTRANCE HOUSE AND CENTRAL PAVILION, WITH SOUTH ENTRANCE HOUSE AND ENGINE HOUSE BEYOND - Fairmount Waterworks, East bank of Schuylkill River, Aquarium Drive, Philadelphia, Philadelphia County, PA

  13. 17. CENTRAL BEDROOM, LOOKING NORTH, SECOND FLOOR. CHANDELIER MANUFACTURED CIRCA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. CENTRAL BEDROOM, LOOKING NORTH, SECOND FLOOR. CHANDELIER MANUFACTURED CIRCA 1900-1910, ORIGINALLY HAD GAS CANDLES ABOVE THE ELECTRIC GLOBES. TIFFANY LAMP MANUFACTURED CIRCA 1895 - Ronald-Brennan House, 631 South Fifth Street, Louisville, Jefferson County, KY

  14. Cob biomass supply for bioenergy in the north central USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn (Zea mays L) cobs are being evaluated as a potential bioenergy feedstock for combined heat and power generation (CHP) and conversion into a liquid biofuel. The objective of this study was to determine corn cob availability in north central U.S. (Minnesota, North Dakota, and South Dakota) using...

  15. North wall, central part, showing doors to compressor room at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    North wall, central part, showing doors to compressor room at left and plant switch house at right (series 1 of 4) - Bureau of Mines Metallurgical Research Laboratory, Original Building, Date Street north of U.S. Highway 93, Boulder City, Clark County, NV

  16. North wall, central part, showing partial partition wall at left. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    North wall, central part, showing partial partition wall at left. This area is labeled “Pioneering Research” on drawing copy NV-35-B-5 (submitted with HABS No. NV-35-B) (series 2 of 4) - Bureau of Mines Metallurgical Research Laboratory, Original Building, Date Street north of U.S. Highway 93, Boulder City, Clark County, NV

  17. WILD POTATOES (SOLANUM SECTION PETOTA) OF NORTH AND CENTRAL AMERICA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solanum section Petota, the potato and its wild relatives, contains about 200 wild species distributed from the southwestern United States, to central Argentina and adjacent Chile. Although most species occur in South America, a secondary center of diversity peaks at 20 degrees north in the central ...

  18. First oilfields of the Central and Northern North Sea

    SciTech Connect

    Swarbrick, R.E. ); Martin, J.A. )

    1991-03-01

    Only 25 years ago the areas now termed the Central and Northern North Sea were the true frontier exploration basins. Stratigraphy and structure were essentially unknown, except inferences drawn from the Mesozoic outcrops of Britain and Denmark. At that time the majority of small British onshore oil fields were reservoired in Paleozoic strata. In the Central North Sea, oil was first discovered in Paleocene deep-water sandstone and Upper Cretaceous chalk reservoirs. The first commercial reserves were proven with the discovery of the Ekofisk field (Upper Cretaceous) in 1969 and Forties field (Paleocene) in 1970, both now classed as giants. Subsequently stratigraphically deeper reservoirs were established, including Jurassic sandstones (Piper field) and Permian carbonates and sandstones (Auk and Argyll fields). Diversity of trap type and reservoir age is now a hallmark of the Central North Sea basin. In the Northern North Sea, the first exploration well in 1971 on the Brent field structure, a true wildcat whose nearest UK well control was 320 mi to the south, found oil in Middle Jurassic deltaic sandstones. A spate of discoveries on similar tilted fault blocks with Middle Jurassic and underlying Triassic alluvial-fluvial sandstone targets followed. Later, Upper Jurassic deep-water sandstones became established as a further significant reservoir with the Brae field and Magnus field discoveries. Original seismic data, well prognoses, and structure maps tell the story of these early discoveries. Public response in Norway and the UK to the emergence of the North Sea oil province on their doorstep will be reviewed.

  19. Assessing Cultural Change in North-Central New Mexico.

    ERIC Educational Resources Information Center

    Eastman, Clyde

    A study conducted during the summer of 1969 researched the concept of culture with regard to the acculturation process of Spanish Americans. The Spanish Americans of north-central New Mexico were compared with the Anglo Americans living within that region. Data were collected on 799 adults from the 2 groups by means of personal interviews. Factor…

  20. 3. VIEW LOOKING NORTH WEST OVER CENTRAL ATLANTIC WITH ATLANTIC ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW LOOKING NORTH WEST OVER CENTRAL ATLANTIC WITH ATLANTIC OCEAN IN THE FOREGROUND. DENNIS HOTEL, BLENHEIM HOTEL, AND MARLBOROUGH HOTEL (LEFT TO RIGHT) ARE LOCATED IN THE CENTER OF THE PHOTOGRAPH. THE CLARIDGE HOTEL IS THE HIGHRISE IMMEDIATELY TO THE RIGHT OF THE MARLBOROUGH HOTEL - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  1. 18. SOUTH CENTRAL SECTION OF HISTORIC DISTRICT LOOKING NORTH TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. SOUTH CENTRAL SECTION OF HISTORIC DISTRICT LOOKING NORTH TO WATER TOWER (Buildings No. 43, 42, 78) (Copy negative made from National Archives negative No. 92-F-61B-5) - Fort Sheridan, 25 miles Northeast of Chicago, on Lake Michigan, Lake Forest, Lake County, IL

  2. Rural People and Their Resources: North-Central New Mexico.

    ERIC Educational Resources Information Center

    Taylor, Marlowe M.

    The general objective of a study conducted in the 1950's was to describe the physical and human resources of the rural areas in north-central New Mexico. The specific objectives were (1) to inventory and classify the land, labor, and capital resources, (2) to determine levels and sources of incomes of these households, and (3) to appraise some of…

  3. 76 FR 1594 - North Central Idaho Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-11

    ...The North Central Idaho RAC will meet in Grangeville, Idaho. The committee is meeting as authorized under the Secure Rural Schools and Community Self-Determination Act (Pub. L. 110-343) and in compliance with the Federal Advisory Committee Act. The purpose of the meetings are to discuss and select projects for 2011 and...

  4. 28. VIEW OF CENTRAL SECTION OF MILL FROM NORTH. COMPRESSOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. VIEW OF CENTRAL SECTION OF MILL FROM NORTH. COMPRESSOR ROOM BELOW PRECIPITATION FLOOR IS VISIBLE AT LOWER LEFT; THE SECONDARY THICKENER ADDITION IS TO THE RIGHT WITH SECONDARY THICKENER No. 7 OFF VIEW TO RIGHT. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  5. Wind energy resource atlas. Volume 2. The North Central Region

    SciTech Connect

    Freeman, D.L.; Hadley, D.L.; Elliott, D.L.; Barchet, W.R.; George, R.L.

    1981-02-01

    The North Central atlas assimilates six collections of wind resource data: one for the region and one for each of the five states that compose the North Central region (Iowa, Minnesota, Nebraska, North Dakota, and South Dakota). At the state level, features of the climate, topography and wind resource are discussed in greater detail than is provided in the regional discussion, and that data locations on which the assessment is based are mapped. Variations, over several time scales, in the wind resource at selected stations in each state are shown on graphs of monthly average and international wind speed and power, and hourly average wind speed for each season. Other graphs present speed direction and duration frequencies of the wind at these locations.

  6. 6. VIEW LOOKING NORTH ON SIXTH STREET, ACROSS CENTRAL AVENUE. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW LOOKING NORTH ON SIXTH STREET, ACROSS CENTRAL AVENUE. THE BUILDING ON THE RIGHT IS BUILDING 551, BUILT IN 1953 AS A WAREHOUSE AND METAL FABRICATION SHOP. THE BUILDING ON THE LEFT IS BUILDING 334, ALSO BUILT IN 1953, AS THE ELECTRICAL AND GENERAL MAINTENANCE SHOP. IN THE CENTER OF THE PHOTOGRAPH IN THE BACKGROUND IS BUILDING 374, THE AQUEOUS PROCESS WASTE TREATMENT PLANT. - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

  7. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  8. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  9. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  10. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 18 2014-07-01 2014-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  11. 40 CFR 81.124 - North Central Oklahoma Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false North Central Oklahoma Intrastate Air... Air Quality Control Regions § 81.124 North Central Oklahoma Intrastate Air Quality Control Region. The North Central Oklahoma Intrastate Air Quality Control Region consists of the territorial...

  12. 40 CFR 81.160 - North Central Coast Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false North Central Coast Intrastate Air... Air Quality Control Regions § 81.160 North Central Coast Intrastate Air Quality Control Region. The North Central Coast Intrastate Air Quality Control Region (California) consists of the territorial...

  13. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  14. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 18 2014-07-01 2014-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  15. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  16. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  17. 40 CFR 81.234 - North Central West Virginia Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false North Central West Virginia Intrastate... Designation of Air Quality Control Regions § 81.234 North Central West Virginia Intrastate Air Quality Control Region. The North Central West Virginia Intrastate Air Quality Control Region consists of the...

  18. 40 CFR 81.250 - North Central Kansas Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false North Central Kansas Intrastate Air... Air Quality Control Regions § 81.250 North Central Kansas Intrastate Air Quality Control Region. The North Central Kansas Intrastate Air Quality Control Region consists of the territorial area...

  19. Paleocurrent analysis of Cretaceous Mitchell Formation, north-central Oregon

    SciTech Connect

    Sandefur, C.A.; Fisk, L.H.

    1989-03-01

    Cretaceous sedimentary rocks in north-central Oregon contain both potential petroleum source rocks and reservoir rocks. Thus, determining their extent under the cover of Tertiary volcanics is of great importance to future petroleum exploration in the southern portion of the Columbia basin. Limited studies of sediment transport direction have been previously reported by several workers; however, no conclusive evidence was obtained. This study was undertaken to resolve the differences in the previously presented interpretations. The outcropping sedimentary sequence represents part of a subsea fan complex consisting of fan-apron facies turbidites and mudstones (Hudspeth mudstone facies) and channel-facies conglomerates and sandstones (Gable Creek conglomerate facies). Paleocurrent data derived from sole marks, flute casts, clast imbrication, and alignment of elongate plant fragments document that sediment transport was primarily from the south-southeast toward the north-northwest. Thus, the greatest potential for petroleum production from Cretaceous sediments in north-central Oregon lies to the west and northwest of the Mitchell area in northeast-southwest elongated rift basins. These basins, presumably containing thick accumulations of Cretaceous marine sediment fill, are now evidenced by large gravity and magnetic lows.

  20. Neogene Extension of the Central North Arm of Sulawesi, Indonesia

    NASA Astrophysics Data System (ADS)

    Rudyawan, A.; Hall, R.; White, L. T.

    2014-12-01

    The peculiar K-shape of Sulawesi has been the subject of geological interest for many years. The east-west trend of the North Arm is commonly considered to have formed by crustal shortening of an intra-oceanic arc built on Eocene ocean crust. However, recent onshore and offshore geological studies suggest an important role for Neogene extension. Field mapping and dating of the pre-Neogene basement indicates that Sulawesi's North Arm constitutes more than a simple oceanic arc. Paleogene granites in this region suggest the basement includes either evolved arc crust or continental crust. LA-ICP-MS U-Pb dating of zircons shows that Paleogene granites have few inherited ages whereas Neogene granites contain Palaeozoic and Proterozoic inherited zircon cores, suggesting melting of Australian continental crust. Biostratigraphic dating of Neogene shallow marine sedimentary rocks on land indicates two distinct periods of sedimentation: Middle Miocene and Late Miocene-Pliocene. Field observations and remote sensing interpretation identify two major fault trends: E-W Neogene basin-bounding faults and young NW-SE strike-slip faults. Offshore seismic surveys show several major sequences separated by regional unconformities in Gorontalo Bay, south of the North Arm, where there was deposition of more than 6 km of sediments. We correlate the thickest package south of the central North Arm, up to 5 sec TWT, with thick marine reworked volcanic ash deposits of Pliocene age mapped on land in the North Arm, on the Togian Islands in Gorontalo Bay, and in the East Arm of Sulawesi. We interpret the land and offshore record to indicate arc-continent collision and underthrusting of Australian crust in the Early Miocene (c.22 Ma). There were several subsequent episodes of extension. A metamorphic core complex formed on land in the Middle Miocene (c.15 Ma), and later renewed extension was linked to initiation of southward subduction of the Celebes Sea in the Late Miocene-Early Pliocene (c.5 Ma).

  1. Regional geothermal exploration in north central New Mexico. Final report

    SciTech Connect

    Icerman, L.

    1984-02-01

    A broad-based geothermal resource reconnaissance study covering Bernalillo, Los Alamos, Rio Arriba, San Miguel, Sandoval, Santa Fe, Taos, Torrance, and Valencia counties in north central New Mexico was conducted from June 15, 1981, through September 30, 1983. Specific activities included the compilation of actual temperature, bottom-hole temperature gradient, and geotemperature data; tabulation of water chemistry data; field collection of temperature-depth data from existing wells; and drilling of temperature gradient holes in the Ojo Caliente, San Ysidro, Rio Puerco, and Polvadera areas. The data collected were used to perform: (1) a regional analysis of the geothermal energy potential of north central New Mexico; (2) two site-specific studies of the potential relationship between groundwater constrictions and geothermal resources; (3) an evaluation of the geothermal energy potential at Santa Ana Pueblo; (4) a general analysis of the geothermal energy resources of the Rio Grande Rift, including specific data on the Valles Caldera; and (5) an evaluation of the use of geothermometers on New Mexico groundwaters. Separate abstracts were prepared for individual chapters.

  2. Miocene isotope chronostratigraphy: North-central Gulf of Mexico

    SciTech Connect

    Trainor, D.M.; Williams, D.F. )

    1991-03-01

    Isotope chronostratigraphy has proven extremely useful in providing high resolution stratigraphic correlations and detailed information relating to the complex nature of sediment accumulation rates in Plio-Pleistocene exploration wells of the north-central Gulf of Mexico (GOM). Current research on the isotopic composition of foraminifera recovered from Miocene age sediments in the north-central GOM indicate that the glacio-eustatic cycles documented in the Plio-Pleistocene are found to continue into the late Miocene. During the middle Miocene ample isotopic signals (3 per mil) exist to provide a high resolution stratigraphy. {delta}{sup 18}O data from the planktonic foraminifera Orbulina universa from Eureka core 66-73 in the Desoto Canyon form a relatively complete record from approximately 8.5-16 Ma. The record displays a greater than 3 per mil range in {delta}{sup 18}O values through the middle Miocene. This Miocene {delta}{sup 18}O record from E66-73 is compared to exploration wells from the following areas: Mississippi Canyon, central GOM, East Breaks, South Galveston, and the Green Canyon. In the downdip, deeper water sections, the primary water column signal appears to be well preserved through the middle Miocene. When working updip in shallower water depths, there appears to be some diagenetic zones displaying extremely negative {delta}{sup 18}O values ({gt}-6 per mil) that could be related to fluid migration events or possibly related to sand occurrence. Also found in these updip wells is a zone of consistent diagenetic overprint in the lower section of the well. In this interval, the base line for the {delta}{sup 18}O values is shifted by as much as 3-4 per mil in the negative direction.

  3. 15. The second story in the north segment of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. The second story in the north segment of the building was originally constructed as a restaurant. The north wall of the dining room retains the original wood wainscot and double-hung windows. At some undetermined time, a building was constructed on the adjacent property; blocking the windows in the dining room. Several chimneys with stove-pipe connections occur in the room. The members seen on the floor are part of a system recently installed to support the failing roof. Credit GADA/MRM. - Stroud Building, 31-33 North Central Avenue, Phoenix, Maricopa County, AZ

  4. Geothermal gradient drilling, north-central Cascades of Oregon, 1979

    SciTech Connect

    Youngquist, W.

    1980-01-01

    A geothermal gradient drilling program was conducted on the western flank of the north-central Cascade Mountains in Oregon. Six wells were drilled during this program, although in effect seven were drilled, as two wells were drilled at site 3, the second well, however, actually going to a lesser depth than the first. Three of the wells (3, 4, and 5) were drilled in areas which topographically are subject to strong throughflows of ground water. None of these wells reached the regional water table, and all showed essentially isothermal geothermal gradients. The single well which was started essentially at the water table (well 6) shows a linear temperature rise with depth essentially from the top of the well bore. Well No. 2 shows an isothermal gradient down to the level of the regional water table and then shows a linear gradient of about 70/sup 0/C/km from the regional water table to total depth.

  5. Thermal Evolution of the North-Central Gulf Coast

    NASA Astrophysics Data System (ADS)

    Nunn, Jeffrey A.; Scardina, Allan D.; Pilger, Rex H., Jr.

    1984-12-01

    The subsidence history of the North Louisiana Salt Basin, determined from well data, indicates that the region underwent extension during rifting and has since passively subsided due to conductive cooling of the lithosphere. Timing of the rifting event is consistent with opening of the Gulf of Mexico during Late Triassic to Early Jurassic time. Crustal extension by a factor of 1.5 to 2 was computed from "tectonic" subsidence curves. However, data from the early subsidence history are insufficient to distinguish between uniform and nonuniform extension of the lithosphere. The magnitude of extension is in good agreement with total sediment and crustal thicknesses from seismic refraction data in the adjacent Central Mississippi Salt Basin. The temperature distribution within the sediments is calculated using a simple heat conduction model. Temperature and subsidence effects of thermal insulation by overlying sediments are included. The computed temperature distribution is in good agreement with bottom hole temperatures measured in deep wells. Temperature histories predicted for selected stratigraphic horizons within the North Louisiana Salt Basin suggest that thermal conditions have been favorable for hydrocarbon generation in the older stata. Results from a two-dimensional heat conduction model suggest that a probable cause for the early formation of the adjacent uplifts is lateral heat conduction from the basin. Rapid extension of the lithosphere underneath areas with horizontal dimensions of 50-100 km produces extremely rapid early subsidence due to lateral heat conduction. The moderate subsidence rate observed in the North Louisiana Salt Basin during the Jurassic and Early Cretaceous suggests slow extension over a long period of time.

  6. Provenance of sandstones in the Golconda terrane, north central Nevada

    SciTech Connect

    Jones, E.A. )

    1991-02-01

    The upper Paleozoic Golconda terrane of north-central Nevada is a composite of several structurally bounded subterranes made of clastic, volcanic, and carbonate rocks. The clastic rocks provide important clues for the interpretation of the provenance and paleogeographic settings of the different lithologic assemblages found in these subterranes. Two petrographically distinct sandstones are identified in the Golconda terrane in the Osgood Mountains and the Hot springs Range of north-central Nevada. The sandstone of the Mississippian Farrel Canyon Formation, part of the Dry Hills subterrane, is characterized by quartzose and sedimentary and lithic-rich clasts with a small feldspar component. in contrast, the sandstone of the Permian Poverty Peak (II) subterrane is a silty quartzarenite with no lithic component, and a very limited feldspar component. The sandstone of the Farrel Canyon Formation is similar to nonvolcanic sandstones reported from elsewhere in the Golconda terrane. Modal data reflect a provenance of a recycled orogen and permit the interpretation that it could have been derived from the antler orogen as has been proposed for other sandstones of the golconda terrane. The sandstone of the Poverty Peak (II) subterrane is more mature than any of the other sandstones in either the Golconda terrane, the Antler overlap sequence, or the Antler foreland basin sequence. Modal data put the Poverty Peak (II) sandstone in the continental block provenance category. The distinct extrabasinal provenances represented in these different sandstones support the idea that the Golconda basin was made up of complex paleogeographic settings, which included multiple sources of extrabasinal sediment.

  7. Geology and evolution of lakes in north-central Florida

    USGS Publications Warehouse

    Kindinger, J.L.; Davis, J.B.; Flocks, J.G.

    1999-01-01

    Fluid exchange between surficial waters and groundwater in karst environments, and the processes that control exchange, are of critical concern to water management districts and planners. High-resolution seismic data were collected from 30 lakes of north-central Florida. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: (1) karstification or dissolution of the underlying limestone, and (2) the collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phases: (1) active subsidence or collapse phase (young); (2) transitional phase (middle age); (3) baselevel phase (mature); and (4) polje (drowned prairie) - broad flat-bottom that have one or all phases of sinkhole. Using these criteria, Florida lakes can be classified by size, fill, subsurface features, and geomorphology.Fluid exchange between surficial waters and groundwater in karst environments, and the processes that control exchange, are of critical concern to water management districts and planners. High-resolution seismic data were collected from 30 lakes of north-central Florida. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: (1) karstification or dissolution of the underlying limestone, and (2) the collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phased: (1) active subsidence or collapse phase (young); (2) transitional phase (middle age); (3) baselevel phase

  8. Post-Ellesmerian depositional sequences of central North Slope subsurface

    SciTech Connect

    Noonan, W.G.

    1985-04-01

    Detailed electrical-log correlations of bedding in the Mesozoic to recent intervals define nearly time-equivalent stratigraphic units. Basinal depositional minima separate them into depositional cycles of 15 to 40-m.y. duration, and sequences of similar cycles correspond to the major episodes of Arctic tectonism. The close of the Sag River cycle in Pleinsbachian time ended the Ellesmerian sequence of accretionary tectonics and northerly continental provenance. Long,oscillating uplift to the northwest during the Jurassic Kingak cycle, and five or more subcycles of emergence along an ancestral Barrow arch rift shoulder during the Lower Cretaceous Kup River cycle show that the Barrovian sequence accompanied Arctic rifting. The Brookian sequence records a time of Arctic seafloor spreading coincident with underthrusting of the North Slope block toward a convergent Pacific margin. A series of major overthrusts onto the block from this margin were sources for Lower Torok, Nanushuk, Schrader Bluff, Prince Creek, and Franklin Bluffs cycles. The lower Torok source was in a distant westerly direction, and those of the following cycles became progressively closer and more southerly, ending near the present position of the central and western Brooks Range. A collision between Alaska and Siberia in mid-Tertiary time initiated the Eurekan sequence of circum-arctic compressional tectonics. The North Slope block was tilted northeast, and the Nuwok cycle was derived from the resulting regional erosion. Similar tilting and erosion beginning in the Pleistocene started the Gubik cycle that is still being deposited.

  9. Bundled slaty cleavage in laminated argillite, north-central minnesota

    USGS Publications Warehouse

    Southwick, D.L.

    1987-01-01

    Exceptional bundled slaty cleavage (defined herein) has been found in drill cores of laminated, folded, weakly metamorphosed argillite at several localities in the early Proterozoic Animikie basin of north-central Minnesota. The cleavage domains are more closely spaced within the cleavage bundles than outside them, the mean tectosilicate grain size of siltstone layers, measured normal to cleavage, is less in the cleavage bundles than outside them, and the cleavage bundles are enriched in opaque phases and phyllosilicates relative to extra-bundle segments. These facts suggest that pressure solution was a major factor in bundle development. If it is assumed that opaque phases have been conserved during pressure solution, the modal differences in composition between intra-bundle and extra-bundle segments of beds provide a means for estimating bulk material shortening normal to cleavage. Argillite samples from the central part of the Animikie basin have been shortened a minimum of about 22%, as estimated by this method. These estimates are similar to the shortening values derived from other strain markers in other rock types interbedded with the argillite, and are also consistent with the regional pattern of deformation. ?? 1987.

  10. Late quaternary geologic framework, north-central Gulf of Mexico

    USGS Publications Warehouse

    Kindinger, Jack G.; Penland, Shea; Williams, S. Jeffress; Brooks, Gregg R.; Suter, John R.; McBride, Randolph A.

    1991-01-01

    The geologic framework of the north-central Gulf of Mexico shelf is composed of multiple, stacked, delta systems. Shelf and nearshore sedimentary facies were deposited by deltaic progradation, followed by shoreface erosion and submergence. A variety of sedimentary facies has been identified, including prodelta, delta fringe, distributary, lagoonal, barrier island, and shelf sand sheet. This study is based on the interpretation and the synthesis of > 6,700 km of high-resolution seismic profiles, 75 grab samples, and 77 vibracores. The nearshore morphology, shallow stratigraphy, and sediment distribution of the eastern Louisiana shelf are the products of transgressive sedimentary processes reworking the abandoned St. Bernard delta complex. Relatively recent Mississippi delta lobe consists primarily of fine sand, silt, and clay. In the southern portion of the St. Bernard delta complex, asymmetrical sand ridges (>5 m relief) have formed as the result of marine reworking of distributary mouth-bar sands. Silty sediments from the modern Mississippi Birdsfoot delta onlap the St. Bernard delta complex along the southern edge. The distal margin of the St. Bernard complex is distinct and has a sharp contact on the north near the Mississippi Sound barrier island coastline and a late Wisconsinan delta to the south. The Chandeleur Islands and the barrier islands of Mississippi Sound have been formed by a combination of Holocene and Pleistocene fluvial processes, shoreface erosion, and ravinement of the exposed shelf. Sediments underlying the relatively thin Holocene sediment cover are relict fluvial sands, deposited during the late Wisconsinan lowstand. Subsequent relative sea-level rise allowed marine processes to rework and redistribute sediments that formed the nearshore fine-grained facies and the shelf sand sheet.

  11. Geologic characteristics of the central stretch of the Ticona Channel, north-central Illinois

    USGS Publications Warehouse

    Willems, B.A.; Malone, D.H.; Pugin, A.

    2007-01-01

    The Ticona Channel is located in north-central Illinois and occurs in Grundy, LaSalle, and Putnam counties. It is a buried bedrock valley that served as the principal paleodrainage system in north-central Illinois during the Illinoian and pre-Illinoian. This study focused on the part of the Ticona Channel within the Leonore 7.5??? Quadrangle. The geometry and stratigraphy of sediments that fill the Ticona Channel were investigated using high-resolution, shallow seismic reflection profiling, traditional field geologic mapping techniques, borehole data, and water-well-log data. The valley is about 2 km (1 mi) wide and approximately 60 m (200 ft) deep. The U-shape channel is straight, trends east-west, and has only one mappable tributary. The valley is carved into the Pennsylvanian Carbondale Formation in the eastern part of the study area; it has incised into the Ordovician Prairie du Chien Group in the west. At its base, the Ticona Channel is filled with the Pearl Formation, which is coarse-grained sand and gravel that was deposited during the Illinoian glaciation. The Pearl Formation is overlain by Illinoian till of the Glasford Formation and is capped by Wedron Group sediments from the Wisconsinan stage. Copyright ?? 2007. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

  12. Insect Pollination at North Central Regional Plant Introduction Station – Past and Present

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The North Central Regional Plant Introduction Station, or NCRPIS, is a joint venture among USDA-ARS, the Agricultural Experimental Stations of the 12 North Central States, and Iowa State University (ISU). As a component of the National Plant Germplasm System (NPGS), NCRPIS is dedicated to the conse...

  13. Tectonic significance of Currant Creek formation, north-central Utah

    SciTech Connect

    Isby, J.S.; Picard, M.D.

    1984-07-01

    The Currant Creek Formation is composed of conglomerate, sandstone, and fine-grained clastic rocks that crop out along the northwestern margin of the Uinta basin in north-central Utah. Lateral gradations in grain size define proximal, medial, and distal parts of coalescing alluvial-fan deposits that prograded eastward from the active Sevier-Laramide orogenic belt during Maestrichtian through Paleocene (.) time. Paleocurrent directions indicate a dominant southerly transport direction and a minor easterly component. Strong east and southeasterly directions, measured in imbricated clasts and in sand lenses in conglomerate, indicate multiple source areas for the detritus. Source of the coarse-grained detritus in the Currant Creek Formation was the Charleston thrust sheet. Conglomeratic clasts are composed of Precambrian and Cambrian quartzite, chert derived from Cambrian and Mississippian carbonate beds, and Pennsylvanian sandstone. These rocks are exposed in the upper plate of the Charleston thrust near Deer Creek Reservoir, Mount Timpanogos, and Strawberry Reservoir. At Big and Little Cottonwood Canyons, the same rocks are exposed in the lower plate.

  14. Revised draft: North Central Regional geologic characterization report. Volume 1

    SciTech Connect

    Not Available

    1984-11-01

    This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on the disqualifying factor and the screening variables to be used in region-to-area screening. These factors and variables include hydrologically significant natural resources, rock mass extent, post-emplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major groundwater discharge zones, water resources, groundwater salinity, and state of stress. Information is presented on age, areal extent, shape, thickness of overburden, composition, texture, degree and type of alteration, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crustal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline rock bodies; groundwater resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the subject rock bodies. A discussion of the relationship between the DOE Siting Guidelines and the geologic disqualifying factor and regional screening variables to be used in the region-to-area screening process is also presented.

  15. North Central Regional geologic characterization report. Volume 1. Final report

    SciTech Connect

    Not Available

    1985-08-01

    This report presents available geologic information pertinent to siting a repository for high-level nuclear waste in crystalline rock in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. For each of the states within the North Central Region, information is provided on the geologic disqualifying factor and the geologic regional screening variables to be used in region-to-area screening. The geologic factor and variables include deep mines and quarries, rock mass extent, post-emplacement faulting, suspected Quaternary faulting, seismicity, rock and mineral resources, major groundwater discharge zones, groundwater resources, state of stress, thickness of rock mass, and thickness of overburden. Information is presented on age, areal extent, shape, composition, texture, degree and type of alteration, thickness, and structural features associated with each rock body or complex. Regional seismic and tectonic information is presented, including patterns of earthquake occurrence, earthquake magnitudes, horizontal ground accelerations, and vertical crustal movements. Also included are discussions of the rock and mineral deposits or mines located within or near crystalline rock bodies; groundwater resources and regional hydrology; postulated changes in climate and the associated effects; and landforms, surface processes, and surficial materials on or near the rock bodies. A discussion is also presented of the relationship between the US Department of Energy Siting Guidelines (10 CFR 960) and the geologic disqualifying factor and regional screening variables to be used in the region-to-area screening process. 43 figs., 15 tabs.

  16. NDT education improvements through the North Central Collaboration for NDT

    NASA Astrophysics Data System (ADS)

    Larson, B. F.; Wormley, S. J.

    2001-04-01

    The North Central Collaboration for Education in NDE/NDT is an effort aimed at enhancing NDE education and improving articulation between community college technician programs and university technical degree programs. NDT instructors at four community colleges are working with the staff at the Center for NDE at Iowa State University. Through this arrangement, advanced teaching methods and new materials that allow students to learn concepts better and in less time are being developed. For example, materials have been developed that will facilitate the use of an X-ray inspection simulation program in teaching basic radiography. Course materials have been developed and posted on the Internet that allow instructors to use interactive Java applets to better illustrate and explain difficult to grasp concepts. Some of the materials introduce subjects that are not currently extensively taught such as real-time radiography and distance-amplitude-correction (DAC) through curved surfaces. This paper will review NDT technician education, discuss the need for improvement in the methods used to educate technicians and highlight some of the efforts of the collaboration.

  17. Parasitism of Dasineura oxycoccana (Diptera: Cecidomyiidae) in North Central Florida.

    PubMed

    Roubos, Craig R; Liburd, Oscar E

    2013-06-01

    Blueberry gall midge, Dasineura oxycoccana (Johnson), is a key pest of blueberries in Florida. As a larva, this insect feeds in developing flower and leaf buds. Management of D. oxycoccana relies principally on chemical insecticides; however, efficacy is limited because D. oxycoccana is sheltered within the plant during most of its life cycle. Natural enemies, particularly parasitoids, may play an important role in regulating D. oxycoccana populations. To determine the seasonal dynamics and parasitism rates of eulophid and platygastrid wasps parasitizing D. oxycoccana larvae, we sampled D. oxycoccana larvae by collecting infested blueberry leaf buds from a minimally-managed farm in north central Florida. Midge larvae were examined under a microscope to determine parasitism status of host instars. Parasitism rates ranged from 25 to 40% over the 3-yr study. Percent parasitization was significantly higher in third instars than first or second instars. Midge larvae in the centers of leaf buds were significantly less likely to be parasitized than larvae in outer layers of leaf buds. Thirty-seven percent of midge larvae had been parasitized multiple times, suggesting these parasitoids do not discriminate between parasitized and unparasitized hosts. Implications for pesticide use in relation to the conservation of natural enemies and management of D. oxycoccana populations are discussed. PMID:23726050

  18. Multiple deformation at the western edge of the Carolina slate belt, north-central North Carolina

    SciTech Connect

    Hibbard, J.P.; Shell, G.S.; Wilkins, J.K. ); Samson, S.; Wortman, G. . Dept. of Geology)

    1994-03-01

    In north-central North Carolina, volcanic-plutonic rocks of the Carolina slate belt are separated from gneisses of the Milton belt to the west by a wide, ENE-trending, polygenetic structural zone. Within a portion of this zone, the Country Line Creek complex (CLCC) forms the western edge of the slate belt. Rocks of the CLCC span a wide age range and include mafic and granitoid gneisses with subordinate pelitic schist, granitoid pegmatite, and a concordant sheet-like intrusion, the Yanceyville metagranite. The complex is heterogeneously deformed and metamorphosed. Along the SE margin of the structural zone, steeply-dipping, strongly foliated biotite granitoid and mafic gneisses of the complex appear to be intruded by the Roxboro metagranite of the Carolina slate belt. To the NW, in more interior portions of the zone, the CLCC is affected by multiphase foliations and folds that record a dextral oblique normal shear event. Here, the Yanceyville metagranite is affected by a strong foliation that is folded. A preliminary new date on the Roxboro pluton of ca. 545 Ma, indicates a Late Precambrian or older timing of deformation along the SE margin of the zone. In contrast, a preliminary, ca. 340 Ma, age on the Yanceyville metagranite indicates multiple stage Late Paleozoic deformation for interior portions of the zone. Regional structural and isotopic data hint that the Precambrian deformation may record initial interactions between the Milton and Carolina slate belts. Subsequently, this contact was reactivated during Alleghanian orogenesis.

  19. Heat flow in the north-central Colorado Plateau

    NASA Astrophysics Data System (ADS)

    Bodell, John Michael; Chapman, David S.

    1982-04-01

    We report new heat flow measurements at 25 evenly distributed sites in the north-central Colorado Plateau. Heat flow values computed for these new sites and one previously published site range from 43 to 116 mW m-2 but fall into the following distinct subsets related to physiographic and tectonic elements within the Plateau: (1) heat flow of 51 mW m-2 (12 sites; s.d. 6) in the San Rafael Swell and Green River Desert which constitute the core of the Colorado Plateau at this latitude, (2) heat flows of 69 mW m-2 (5 sites; s.d. 10) and 88 mW m-2 (4 sites; s.d. 19) in successive parallel north-south bands approaching the Wasatch Plateau to the west but still 80 km east of the Basin and Range physiographic boundary, (3) heat flow of 64 mW m-2 (5 sites; s.d. 2) along the Salt Anticline trend which strikes northwest in the region of Moab, Utah. Heat flow results for the entire Colorado Plateau have been reexamined in view of our new results, and the overall pattern supports the concept of a low heat flow `thermal interior' for the plateau surrounded by a periphery some 100 km wide having substantially higher heat flow. Average heat flow in the thermal interior is about 60 mW m-2 compared to 80-90 mW m-2 in the periphery. This regional heat flow pattern supports a model of Tertiary lithospheric thinning under the Colorado Plateau whereby the plateau is still in transient thermal response and a 15-20 m.y. lag between uplift and corresponding surface heat flow anomaly is to be expected. The position of the heat flow transition between our interior and peripheral regions in the northwest plateau is roughly consistent with lateral warming and weakening of the Colorado Plateau lithosphere initiated at the Basin and Range boundary some 20 m.y. ago.

  20. A refined age grid for the Central North Atlantic

    NASA Astrophysics Data System (ADS)

    Luis, J. M.; Miranda, J.

    2012-12-01

    We present a digital model for the age of the Central North Atlantic as a geographical grid with 1 arc minute resolution. Our seafloor isochrons are identified following the 'grid procedure' described in the work of Luis and Miranda (2008). The grid itself, which was initially a locally improved version of the Verhoef et al. (1996) compilation, was improved in 2011 (Luis and Miranda, 2011) and further refined with the inclusion of Russian data north of Charlie Gibbs FZ (personal communication, S. Mercuriev). The location and geometry of the Mid-Atlantic Ridge is now very well constrained by both magnetic anomalies and swath bathymetry data down to ~10 degrees N. We identified an extensive set of chrons 0, 2A, 3, 3A, 4, 4A, 5, 6, 6C, 11-12, 13, 18, 20, 21, 22, 23, 24, 25, 26, 28, 29, 30, 32, 33r, M0, M2, M4, M10, M16, M21 and M25. The ages at each grid node are computed by linear interpolation of adjacent isochrons along the direction of the flow-lines. As a pre-processing step each conjugate pair of isochrones was simplified by rotating one of them about the finite pole of that anomaly and use both, original picks plus rotated ones, to calculate an average segment. Fractures zones are used to constrain the chron's shape. These procedures minimize the uncertainties in locations where on one side of the basin one has good identifications but the other is poorly defined as is typical of many of the old isochrones. Care has also taken to account for locations where significant ridge jumps were found. Ages of the ocean floor between the oldest identified magnetic anomalies and continental crust are interpolated using the oldest ages of the Muller at al. (2008), which were themselves estimated from the ages of passive continental margin segments. This is a contribution to MAREKH project (PTDC/MAR/108142/2008) funded by the Portuguese Science Foundation.

  1. Magnetotelluric Data, North Central Yucca Flat, Nevada Test Site, Nevada

    SciTech Connect

    J.M. Williams; B.D. Rodriguez, and T.H. Asch

    2005-11-23

    Nuclear weapons are integral to the defense of the United States. The U.S. Department of Energy, as the steward of these devices, must continue to gauge the efficacy of the individual weapons. This could be accomplished by occasional testing at the Nevada Test Site (NTS) in Nevada, northwest of Las Vegas. Yucca Flat Basin is one of the testing areas at the NTS. One issue of concern is the nature of the somewhat poorly constrained pre-Tertiary geology and its effects on ground-water flow in the area subsequent to a nuclear test. Ground-water modelers would like to know more about the hydrostratigraphy and geologic structure to support a hydrostratigraphic framework model that is under development for the Yucca Flat Corrective Action Unit (CAU). During 2003, the U.S. Geological Survey (USGS) collected and processed Magnetotelluric (MT) and Audio-magnetotelluric (AMT) data at the Nevada Test Site in and near Yucca Flat to help characterize this pre-Tertiary geology. That work will help to define the character, thickness, and lateral extent of pre-Tertiary confining units. In particular, a major goal has been to define the upper clastic confining unit (UCCU) in the Yucca Flat area. Interpretation will include a three-dimensional (3-D) character analysis and two-dimensional (2-D) resistivity model. The purpose of this report is to release the MT sounding data for north central Yucca Flat, Profile 7, as shown in Figure 1. No interpretation of the data is included here.

  2. Vertical distribution of scandium in the north central Pacific

    NASA Astrophysics Data System (ADS)

    Amakawa, Hiroshi; Nomura, Miho; Sasaki, Kazunori; Oura, Yasuji; Ebihara, Mitsuru

    2007-06-01

    The concentrations of scandium (Sc) in seawater, which have remained unreported since the early 1970s, were determined together with those of yttrium (Y) and lanthanides (Ln) with samples from the north central Pacific Ocean (St. BO-3). The Sc concentration shows a so-called nutrient-like profile: it increases gradually from the surface (about 2 pmol/kg) to the ocean floor (about 20 pmol/kg). That pattern closely resembles those of Y and Ln (correlation coefficient (r) > 0.92). Some light-to-middle Ln (Pr-Tb) exhibit a closer correlation with Sc than do Y, La, or heavy Ln (Ho-Lu). In contrast, Y/Sc and Ln/Sc ratios (elemental abundance ratios) indicate that Sc is depleted compared to either Y or Ln in seawater more than in loess, which represents chemical compositions of crustal material. These observations offer a conflicting view of chemical reactivity related Y, Ln, and Sc: r values show that the chemical reactivity of Sc resembles those of Y and Ln, but differences of Y/Sc and Ln/Sc ratios in seawater and in loess suggest that the chemical reactivity of Sc differs from those of Y and Ln. More Sc data for seawater are necessary to clarify the chemical reactivity of Sc in the ocean. We also propose that comparative studies of vertical profiles of Sc and such elements as Fe, Ti, Zr, and Hf showing so-called nutrient-like profiles at the same oceanic stations would be helpful and effective for clarifying the behavior of Sc in the ocean.

  3. Petroleum exploration of Winnipegosis Formation in north-central North Dakota (Williston basin)

    SciTech Connect

    Guy, W.J. Jr.; Braden, K.W.

    1986-08-01

    The Winnipegosis Formation (Middle Devonian) in north-central Dakota has the greatest potential for large oil reserves in the Williston basin. The Winnipegosis carbonate (50 to 325 ft thick) was deposited in the southeast end of the Elk Point restricted sea. During Winnipegosis deposition, the Williston basin could be divided into two distinct environments: (1) a deep starved basin with accompanying pinnacle reefs separated by interreef, laminated limestone and (2) a surrounding carbonate shelf. Within the carbonate shelf are patch reefs, banks, and tidal flats. Overlying the Winnipegosis carbonate is the Prairie Formation, which has a basal anhydrite (0 to 70 ft thick) and an overlying salt (0 to 650 ft thick). These were deposited in a regressive phase of the Elk Point sea and act as seals for Winnipegosis oil entrapment. Currently, oil production from the Winnipegosis in the Williston basin is from stratigraphic traps and from small structures on the carbonate shelf. The most significant accumulation to date is Temple field, in which 11 wells produce from +/- 20 ft of Winnipegosis dolomite. The pinnacle reef environment has potential for significant oil reserves from 250-ft thick reefs covering 160 ac or less. Two pinnacle reefs have had free-oil recoveries from thin pay zones. The Rainbow/Zama fields in northwest Alberta have an ultimate reserve of more than 1 billion bbl of oil from Keg River reefs, which are correlative and similar to the Winnipegosis reefs in North Dakota. The strong seismic reflection that originates from the Winnipegosis-Prairie evaporite interface provides an excellent means of detecting Winnipegosis reefs. Amplitude of the Winnipegosis reflection is reduced dramatically over the reefs. The resulting dim spot is one criteria used in identifying reefs.

  4. Assessing the potential risks of burial practices on groundwater quality in rural north-central Nigeria.

    PubMed

    Zume, Joseph T

    2011-09-01

    Several cultures of north-central Nigeria do not use community cemeteries. Instead, human remains are buried in and around family compounds, often in shallow and sometimes unmarked graves. At several locations, graves and drinking water wells end up too close to be presumed environmentally safe. This paper reports findings of a pilot study that explored the potential for groundwater contamination from gravesites in some rural settlements of north-central Nigeria. Preliminary results suggest that the long-standing burial practices among some cultures of rural north-central Nigeria may potentially compromise groundwater quality, which is, by far, their most important source of drinking water. PMID:21976208

  5. Anthropogenic warming has decreased water supply in North Central Texas

    NASA Astrophysics Data System (ADS)

    Brikowski, T. H.

    2015-12-01

    North Central Texas, including Dallas-Ft. Worth, the 4th largest metropolitan area in the U.S., has been in a state of drought for most of this 21st Century. Seven million residents there depend almost exclusively on surface water resources, and net water storage declined precipitously until record rainfall in early 2015. Part of the decline in water availability can be attributed to reduced runoff, where despite slightly above normal precipitation, natural basin runoff has declined almost 20% since its peak in the mid-1990's. These changes have coincided with 0.85oC warming above the historical 20th Century mean. Prevalent Vertisol (cracking) soils in the region make runoff especially sensitive to climate variations, and make it difficult to apply traditional hydrologic models to investigate climate-runoff links. Non-parametric (empirical) runoff elasticity methods circumvent these limitations, and are applied here, focusing on the Upper Trinity River basin (UTB). Diagrammatic assessment of UTB temperature-precipitation (T-Pr) runoff elasticity indicates persistent warming greatly increases the risk of reduced runoff, based on historical experience. Evaluation of individual parameter elasticity indicates dry periods since 2000 have primarily been T-driven, in contrast to the Pr-driven 1951-6 drought of record. Observed decline in runoff during 2000-2010 is entirely attributable to increased T. Additional runoff declines from 2011-14 were driven by reduced Pr, augmenting the T-driven reductions. These T effects are most prominent to the west, and decline to minimal extent just east of the UTB. The observed warming can be related to anthropogenic CO2 increase with >95% certainty based on comparison of CMIP5 climate model results for the UTB with and without CO2 forcing. UTB runoff fraction of Pr decreased after 1980 with >97.5% certainty. These results strongly indicate that 21st Century 20% decline in runoff from previous century norms is largely attributable to

  6. Clinoptilolite zeolitized tuff from Central Alborz Range, North Iran

    NASA Astrophysics Data System (ADS)

    Taghipour, Batoul

    2010-05-01

    Zeolites are hydrated alumino-silicates of the alkaline and alkaline earth cations, principally sodium, potassium, calcium, and magnesium (Iijima 1980; Hay 1981). Zeolites occur principally in unmetamorphosed sedimentary rocks and are particularly widespread in volcani-clastic strata (Hay, 1978). Clinoptilolite is a natural zeolite of the heulandite group with the simplified formula of (Na, K)6 Si30 Al6 O72 .nH2. It is the most common natural zeolite found mainly in sedimentary rocks of volcanic origin. Alborz zone is one of the important geological divisions in Iran. This zone is restricted to Kopeh dagh zone in North & Central Iranian zone in South and is a region of active deformation within the broad Arabian-Eurasia collision zone (Allen et al. 2003). The zeolitized green tuff belt from Central Alborz which introduce here are made of volcanoclastic sequence of Karaj Formation. This belt is about 40 km long along Alborz Range and is Eocene in age. Zeolites and associated minerals of this altered vitric tuff studied. Zeolitization took place in some beds of Karaj Formations, with average range of 3 to 300 meters thickness. There are several gypsum lenses which interbed with a widespread green tuff succession in the studied area. On the basis of chemical composition these tuffs are in the range of acid to intermediate volcanic rocks. Also magmatic affinity is calc-alkaline and geological setting of the area belongs to volcanic arc granitoid. Petrographic data has shown that various shape and size of shard glass are the main component of tuffs. Based on the field studies, detail microscopy, XRD and electron microprobe analysis (EMPA), the following main minerals are determined: Clinoptilolite+montmorillonite+crystobalite. Clinoptilolite and smectite are predominant minerals in all altered samples. Concerning the Si/Al ratio of 40 point analyses of glass shards the Alborz tuff has clinoptilolite composition. Otherwise the chemical composition of altered shard glass

  7. Early opening of initially closed Gulf of Mexico and central North Atlantic ocean

    SciTech Connect

    Van Siclen, D.C.

    1984-09-01

    This paper presents ideas on the early opening and evolution of the Gulf of Mexico and the central North Atlantic ocean. It discusses rifting activity, plate tectonics, magnetic anomalies, and the geologic time elements involved.

  8. Pseudotachylite Breccia Veins from Dhala Impact Structure, North Central India: Texture, Mineralogy and Geochemical Characterization

    NASA Astrophysics Data System (ADS)

    Pati, J. K.; Reimold, W. U.; Greshake, A.; Koeberl, C. K.; Pati, P.

    2013-08-01

    This is the first report of pseudotachylitic breccia veins (PTB)in basement granitoids from the Dhala structure, north central India.The host granitoids and PTB show similar REE pattern despite extensive alteration and major element concentration.

  9. Cob biomass supply for combined heat and power and biofuel in the north central USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn (Zea mays L) cobs are being evaluated as a potential bioenergy feedstock for combined heat and power generation (CHP) and conversion into a biofuel. The objective of this study was to determine corn cob availability in north central United States (Minnesota, North Dakota, and South Dakota) usin...

  10. Paleoseismologic Studies of the North Anatolian Fault, Cukurcimen and Ulaslar, North-Central Turkey

    NASA Astrophysics Data System (ADS)

    Hartleb, R. D.; Dolan, J. F.; Kozaci, O.; Seitz, G. G.; Akyuz, H. S.; Barka, A. A.

    2001-12-01

    The central North Anatolian fault (NAF) is a model opportunity to study long-term behavior of continental transforms because of its relative mechanical simplicity and long historic record of earthquakes. We excavated three trenches across the NAF at Cukurcimen, near Refahiye in north-central Turkey on the eastern part of the 1939 M7.9 surface rupture. Measurement of a nearby offset dirt road, together with interviews with residents, indicates that ~9 - 14 m of dextral slip occurred at the site during the 1939 event. Trench stratigraphy is superb, with alternating fine-scale alluvial and marsh deposits, including abundant, laterally-continuous peat horizons. These in-situ peat deposits provide excellent chronological control, which we are utilizing by strategic sampling and AMS 14C analysis. We identified evidence for at least two, and perhaps four, surface ruptures at Cukurcimen. Two distinct event horizons were recognized in trench 1 on the basis of upward fault terminations. The most recent event in trench 1 occurred shortly after deposition of a thin peat horizon (1332 - 1481 AD). We do not have an upper age limit for this event, but the event horizon lies ~75 cm below ground surface. We believe that this is the historical 1583 earthquake which razed Erzincan, and that the 1939 event is not recorded in trench 1. An older, clearly-defined event in trench 1 occurred shortly after deposition of another thin peat horizon (795 - 1022 AD), and before the 1583 (?) event. We suspect that this event is the historical 1045 earthquake. There is also equivocal evidence in trench 1 for an older event that occurred after deposition of a peat dated at BC 538 - 260, and before 795 - 1022 AD. Trench 2 revealed evidence for one event (1939?), peat dates are pending. Trench 3 revealed evidence for two events (probably 1939 and 1583). Additional excavations are planned at this site. We excavated two trenches across the NAF near Ulaslar, 12 km east of Gerede, on the 1944 M7

  11. Central Wind Forecasting Programs in North America by Regional Transmission Organizations and Electric Utilities: Revised Edition

    SciTech Connect

    Rogers, J.; Porter, K.

    2011-03-01

    The report and accompanying table addresses the implementation of central wind power forecasting by electric utilities and regional transmission organizations in North America. The first part of the table focuses on electric utilities and regional transmission organizations that have central wind power forecasting in place; the second part focuses on electric utilities and regional transmission organizations that plan to adopt central wind power forecasting in 2010. This is an update of the December 2009 report, NREL/SR-550-46763.

  12. Distribution (presence / absence) of Culicoides Sonorensis (Diptera: Ceratopogonidae) in Nebraska, South Dakota, and North Dakota: Clarifying the Epidemiology of Bluetongue Disease in the North-Central United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence or absence of the biting midge, Culicoides sonorensis, a primary vector of bluetongue viruses (BTV) in North America, was assessed on ranches and farms across the north-central region of the United States (U.S.), specifically the states of Nebraska, South Dakota, and North Dakota, as pa...

  13. Late Miocene biogeography and paleoclimatology of the central North Atlantic

    USGS Publications Warehouse

    Poore, R.Z.

    1981-01-01

    Quantitative analyses of planktonic foraminiferal assemblages from Deep Sea Drilling Project (DSDP) Holes 334 and 410 demonstrate that subpolar and subtropical faunal provinces existed in the North Atlantic during the late Miocene. Climatic oscillations are clearly recorded in Hole 410 by variations in abundance of the Neogloboquadrina subpolar assemblage. These climatic oscillations have a period of about 1 m.y. Higher frequency oscillations with a periodicity of one to several hundred thousand years are evident from about 6.5 to 7.5 m.y. and are probably present throughout the entire late Miocene. A revised age of 7.0 m.y. is proposed for the first occurrence of the calcareous nannofossil Amaurolithus primus (the Amaurolithus datum). ?? 1981.

  14. Drivers of summer oxygen depletion in the central North Sea

    NASA Astrophysics Data System (ADS)

    Queste, B. Y.; Fernand, L.; Jickells, T. D.; Heywood, K. J.; Hind, A. J.

    2015-06-01

    In stratified shelf seas, oxygen depletion beneath the thermocline is a result of a greater rate of biological oxygen demand than the rate of supply of oxygenated water. Suitably equipped gliders are uniquely placed to observe both the supply through the thermocline and the consumption of oxygen in the bottom layers. A Seaglider was deployed in the shallow (≈ 100 m) stratified North Sea in a region of known low oxygen during August 2011 to investigate the processes regulating supply and consumption of dissolved oxygen below the pycnocline. The first deployment of such a device in this area, it provided extremely high resolution observations, 316 profiles (every 16 min, vertical resolution of 1 m) of CTD, dissolved oxygen concentrations, backscatter and fluorescence during a three day deployment. The high temporal resolution observations revealed occasional small scale events that supply oxygenated water into the bottom layer at a rate of 2±1 μmol dm-3 day-1. Benthic and pelagic oxygen sinks, quantified through glider observations and past studies, indicate more gradual background consumption rates of 2.5±1 μmol dm-3 day-1. This budget revealed that the balance of oxygen supply and demand is in agreement with previous studies of the North Sea. However, the glider data show a net oxygen consumption rate of 2.8±0.3 μmol dm-3 day-1 indicating a localised or short-lived increase in oxygen consumption rates. This high rate of oxygen consumption is indicative of an unidentified oxygen sink. We propose that this elevated oxygen consumption is linked to localised depocentres and rapid remineralisation of resuspensded organic matter. The glider proved to be an excellent tool for monitoring shelf sea processes despite challenges to glider flight posed by high tidal velocities, shallow bathymetry, and very strong density gradients. The direct observation of these processes allows more up to date rates to be used in the development of ecosystem models.

  15. Physical characteristics of stream subbasins in the Blue Earth River Basin, south-central Minnesota and north-central Iowa

    USGS Publications Warehouse

    Lorenz, D.L.; Payne, G.A.

    1992-01-01

    This report presents data describing the physical characteristics of stream basins upstream from selected points on streams in the Blue Earth River basin, located in south-central Minnesota and north-central Iowa. The physical characteristics are the drainage area of the basin, the percentage area of the basin covered only by lakes, the percentage area of the basin covered by both lakes and wetlands, the main-channel length, and the mainchannel slope. The points on the stream include outlets of subbasins of at least five square miles, outfalls of sewage treatment plants, and locations of U.S. Geological Survey gaging stations.

  16. Drivers of summer oxygen depletion in the central North Sea

    NASA Astrophysics Data System (ADS)

    Queste, Bastien Y.; Fernand, Liam; Jickells, Timothy D.; Heywood, Karen J.; Hind, Andrew J.

    2016-02-01

    In stratified shelf seas, oxygen depletion beneath the thermocline is a result of a greater rate of biological oxygen demand than the rate of supply of oxygenated water. Suitably equipped gliders are uniquely placed to observe both the supply through the thermocline and the consumption of oxygen in the bottom layers. A Seaglider was deployed in the shallow (≍ 100 m) stratified North Sea in a region of known low oxygen during August 2011 to investigate the processes regulating supply and consumption of dissolved oxygen below the pycnocline. The first deployment of such a device in this area, it provided extremely high-resolution observations, 316 profiles (every 16 min, vertical resolution of 1 m) of conductivity, temperature, and depth (CTD), dissolved oxygen concentrations, backscatter, and fluorescence during a 3-day deployment.The high temporal resolution observations revealed occasional small-scale events (< 200 m or 6 h) that supply oxygenated water to the bottom layer at a rate of 2 ± 1 µmol dm-3 day-1. Benthic and pelagic oxygen sinks, quantified through glider observations and past studies, indicate more gradual background consumption rates of 2.5 ± 1 µmol dm-3 day-1. This budget revealed that the balance of oxygen supply and demand is in agreement with previous studies of the North Sea. However, the glider data show a net oxygen consumption rate of 2.8 ± 0.3 µmol dm-3 day-1, indicating a localized or short-lived (< 200 m or 6 h) increase in oxygen consumption rates. This high rate of oxygen consumption is indicative of an unidentified oxygen sink. We propose that this elevated oxygen consumption is linked to localized depocentres and rapid remineralization of resuspended organic matter.The glider proved to be an excellent tool for monitoring shelf sea processes despite challenges to glider flight posed by high tidal velocities, shallow bathymetry, and very strong density gradients. The direct observation of these processes allows more up to date

  17. An analysis of the mechanisms of North American pollutant transport to the central North Atlantic lower free troposphere

    NASA Astrophysics Data System (ADS)

    Owen, R. C.; Cooper, O. R.; Stohl, A.; Honrath, R. E.

    2006-12-01

    We use the FLEXPART Lagrangian particle dispersion model and observations from the PICO-NARE station to identify and analyze the transport of North American anthropogenic emissions to the central North Atlantic lower free troposphere (FT) during July 2003. FLEXPART adequately captured the occurrence of CO transport events, simulating all but 1 of the 16 observed events while producing only 3 events not observed. Low-level transport (below 3 km) was responsible for most events. Three case studies of this type are presented. Export from the North American boundary layer in these events was the result of eastward advection over the ocean or transport in a weak warm conveyor belt airflow. Once over the ocean, transport was governed by geostrophic winds between the Azores/Bermuda High (ABH) and transient northerly lows. The varying locations of the ABH and northerly lows determine the pathway of this type of event. As a result, other events similar to those analyzed here reach Europe. Transported below 3 km, these events were observed in the lower FT over the Azores and were accompanied by O3 enhancements. Thus the lower marine FT may provide a transport environment significantly different from the marine boundary layer, where O3 destruction is believed to dominate. In the fourth case study, North American emissions were lofted to 6-8 km in a warm conveyor belt, captured for 2 days in the midtropospheric circulation of the associated cyclone, and then entrained in the same cyclone's dry airstream and transported down to the Azores.

  18. Assessment of Undiscovered Biogenic Gas Resources, North-Central Montana Province

    USGS Publications Warehouse

    U.S. Geological Survey

    2008-01-01

    Application of a geology-based assessment methodology by the U.S. Geological Survey resulted in an estimated mean of 6,192 billion cubic feet of shallow biogenic (continuous) undiscovered gas in the North-Central Montana Province. Oil, gas, and natural gas liquids in conventional accumulations were not assessed.

  19. A review of the North and Central American Megachile subgenus Argyropile subgenus Argyropile mitchell (Hymenoptera: Megachilidas)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A synopsis of the North and Central American subgenus Megachile (Argyropile) and an illustrated key to the species in Spanish and English are provided, Megachile longuisetosa Gonzalez & Griswold, new species, from Mexico and Guatemala, and the previously unknown males of M. sabinensis and M. rossi a...

  20. College and Adult Reading XII: The Twelfth Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Fisher, Joseph A., Ed.

    Consisting of a selection of papers presented at the 1982 and 1983 meetings of the North Central Reading Association, this yearbook includes sections on computers, research, professional issues, and programs. Papers include: "The Computerized Broom Will Sweep Our Future Classrooms: But Not Necessarily Clean" (George E. Mason); "Beyond the…

  1. College and Adult Reading XIII: The Thirteenth Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Fisher, Joseph A., Ed.

    Containing selections of the papers presented at the 1984 and 1985 annual meetings of the North Central Reading Association, this yearbook includes sections on research; reviews of research; professional issues; and program descriptions. Papers include: "Twenty-Five Years of Professional Progress" (James E. Walker); "A Study of Student Alienation…

  2. The montane bee fauna of north central Washington, USA, with floral associations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mountains of north central Washington contain a variety of habitat types, from shrub-steppe to high alpine meadows. While native bee surveys of some surrounding areas of the Columbia Basin are fairly complete, little work has been done in this region to document the diversity of bees found ther...

  3. College and Adult Reading VII: The Seventh Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Wark, David M., Ed.

    Spanning the annual meetings of the North Central Reading Association from 1971 to 1974, this yearbook presents papers dealing with programs and centers, materials and techniques, a new research field, and in honor of Roger S. Pepper. Papers include: "Attitudinal Factors among Marginal Admission Students" (Roger S. Pepper and John A. Drexler,…

  4. Emerging issues in Integrated Pest Management implementation and adoption in the North Central USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a long tradition of integrated pest management (IPM) in the North Central region of the U.S. IPM is difficult to define, and it means different things to different people. But in general it is a philosophy based on multiple tactics to prevent a population from building up to unacceptable da...

  5. Rural Poor Who Could Benefit from Job Retraining in the East North Central States.

    ERIC Educational Resources Information Center

    Konyha, Marvin E.

    Low-income status was the lot of 26% of open-country residents over 15 years of age in the East North Central States, a 1967 sample survey showed. Many residents were unprepared to compete in today's labor market. Of those with low income, 37% had no economic potential because of age (over 65) or disability and needed some form of income…

  6. Rural School-Community Relationships in North Central Montana: The Role of Schools in Rural Communities.

    ERIC Educational Resources Information Center

    Unruh, Rick; Lundt, Jack C.

    1999-01-01

    A telephone survey of 150 north-central Montana rural residents found that they would support increased adult education programs by their schools and more economic and business-related curriculum offerings. Residents of larger towns expressed more agreement with school district consolidation than residents of smaller towns. Implications for rural…

  7. Field Wind Tunnel Testing of Two Silt Loam Soils in the North American Central High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The change from conventional tillage to no-till cropping systems and the emergence of cropping systems with fewer and shorter fallow periods has resulted in reduced wind erosion on the North American Central High Plains. This reduction has been attributed primarily to increased surface coverage by ...

  8. Open-Country Poverty in a Relatively Affluent Area - The East North Central States.

    ERIC Educational Resources Information Center

    Fitzwilliams, Jeanette

    Poverty among open-country households in the East North Central States (11%) was slightly above the incidence found among U.S. whites in general. Incidence of poverty was greatest among the aged, disabled, and small farmers of all ages who made farming their major source of earnings. Of the respondent households in this 1967 survey, 87% had…

  9. College and Adult Reading IX: The Ninth Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Fisher, Joseph A., Ed.

    Drawn from presentations at the 1977 meeting of the North Central Reading Association, this yearbook includes sections on programs and centers; professional training; clinical problems and methods; research; the Roger Pepper Research Award presentation; and the invitational address. Papers include: "Use of Galvanic Skin Response, Heart Rate,…

  10. From the Ground Up: Growing Entrepreneurship in the North Central Region. RRD 191

    ERIC Educational Resources Information Center

    Emery, Mary

    2008-01-01

    More than 300 people in the North Central region added their voices to a discussion on the importance of entrepreneurship to rural community vitality, often traveling long distances to attend one of 11 listening sessions held throughout the region. Among those attending were local leaders, service providers, entrepreneurs, and educators. The…

  11. North Central Campus--State Street, Origin and Destination Traffic Survey.

    ERIC Educational Resources Information Center

    Harrison, Gregory R.

    Vehicular and pedestrian traffic in and about the north central campus of the University of Michigan was surveyed in November 1964 to obtain the traffic and parking data necessary to establish the basic characteristics of vehicular movement and to provide a basis for recommendations to improve area traffic circulation. The report recommends…

  12. Geology and ground-water resources of the Grand Rapids area, north-central Minnesota

    USGS Publications Warehouse

    Oakes, Edward L.

    1970-01-01

    This report is one of a series of studies of geology and ground-water availability conducted in and near selected communities on the Mesabi Iron Range, north-central and northeastern Minnesota. This report describes the geology and ground-water conditions in the 303 square-mile Grand Rapids area.

  13. College and Adult Reading XI: The Eleventh Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Fisher, Joseph A., Ed.

    This yearbook contains selected papers presented at the twenty-third and twenty-fourth annual meetings of the North Central Reading Association, held in October of 1981 and 1982. Papers in the yearbook include: "History of Adult Reading Programs" (Clarence Anderson); "About Creativity and Study Skills" (Mark E. Thompson); "Recent Changes in…

  14. College and Adult Reading X: The Tenth Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Fisher, Joseph A., Ed.

    Including sections on research, programs, and professional problems and issues, this yearbook contains presentations given at the 1978 and 1979 meetings of the North Central Reading Association. Papers include: "The Effects of Anxiety on Reading Comprehension" (David Wark and others); "Some Effects of Anxiety on University Students" (J. Michael…

  15. A Year of Transition: North Central Regional Center for Rural Development Annual Report 2009

    ERIC Educational Resources Information Center

    North Central Regional Center for Rural Development, 2009

    2009-01-01

    The North Central Regional Center for Rural Development (NCRCRD) is one of four centers in the United States that work to improve opportunities and quality of life in rural communities. With funding from the USDA National Institute of Food and Agriculture and the land-grant universities in its 12-state region, the NCRCRD engages Extension…

  16. Cucurbit germplasm collections at the North Central Regional Plant Introduction Station

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The North Central Regional Plant Introduction Station (NCRPIS) in Ames, Iowa, USA is one of four primary Plant Introduction Stations in the National Plant Germplasm System (NPGS), and has responsibility for maintenance, regeneration, characterization, and distribution of the NPGS Cucumis and Cucurbi...

  17. College and Adult Reading VIII: The Eighth Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Fisher, Joseph A., Ed.

    Drawn from the presentations at the eighteenth and nineteenth annual conferences of the North Central Reading Association, this yearbook includes sections on programs and centers; materials and techniques; evaluation; and professional growth and issues. Papers include: "Successfully Effecting Change on Personality Variables through Academic Skills…

  18. Sweet corn growth and yield responses to planting dates of the north central U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sweet corn is planted over a three-month period in the north central U.S. in order to extend availability for fresh market and processing; however, the extent to which development and growth of sweet corn changes during this period is unreported. Field experiments were conducted in 2006 and 2007 to...

  19. Lawn Weeds and Their Control. North Central Regional Extension Publication No. 26.

    ERIC Educational Resources Information Center

    Purdue Univ., Lafayette, IN. Cooperative Extension Service.

    This publication discusses lawn weed control for the twelve state north central region of the country. Written for use by homeowners, the publication focuses on weed identification and proper herbicide selection and application. Identification of weeds and safe and appropriate herbicide use are emphasized. Forty-six weed and turf plants are…

  20. 40 CFR 81.157 - North Central Wisconsin Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of.... The North Central Wisconsin Intrastate Air Quality Control Region consists of the territorial area encompassed by the boundaries of the following jurisdictions or described area (including the territorial...

  1. 40 CFR 81.160 - North Central Coast Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of... North Central Coast Intrastate Air Quality Control Region (California) consists of the territorial area encompassed by the boundaries of the following jurisdictions or described area (including the territorial...

  2. North Central Region 4-H Volunteers: Documenting Their Contributions and Volunteer Development

    ERIC Educational Resources Information Center

    Nippolt, Pamela Larson; Pleskac, Sue; Schwartz, Vicki; Swanson, Doug

    2012-01-01

    Documenting volunteer contributions strengthens Extension partnerships with volunteers. A team of North Central Region 4-H volunteer specialists collaborated to conduct a study of 4-H volunteer contributions and impacts related to working with youth within the 4-H program. Over three thousand (3,332) 4-H volunteers from throughout the 12-state…

  3. An Inventory of Natural, Human, and Social Overhead Capital Resources in North-Central New Mexico.

    ERIC Educational Resources Information Center

    Carruthers, Garrey; Eastman, Clyde

    Concerned with the north-central area of New Mexico (Rio Arriba, Taos, Colfax, Mora, Santa Fe, and San Miguel counties), this inventory describes the situation and delineation of the region, the natural resources (physical characteristics, land, land-ownership patterns, land-use patterns, land-title problems, water resources, and minerals); human…

  4. College and Adult Reading XIV: The Fourteenth Yearbook of the North Central Reading Association.

    ERIC Educational Resources Information Center

    Fisher, Kay E., Ed.; Fisher, Joseph A., Ed.

    Containing selections from the 1987 and 1988 annual meetings of the North Central Reading Association, this yearbook includes sections on research; reviews of research; professional issues; and program descriptions. Papers include: "The Effects of a Secondary Reading Methods Course on Undergraduate Students' Awareness of Reading Skills" (Bruce A.…

  5. Toward a New Definition of Employability. Report by the North Central Indiana Workforce Literacy Task Force.

    ERIC Educational Resources Information Center

    Center for Remediation Design, Washington, DC.

    The North Central Indiana Workplace Literacy Initiative seeks to develop a curriculum management system addressing work force literacy needs and a coordinated human resource investment system meeting individual economic self-sufficiency needs and labor market needs. The workplace of the future will contain six key changes: employers will require…

  6. Use and breeding of forage grasses in the North Central USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage grasses are used for conservation harvesting, usually hay or balage, and for grazing within the North Central region of the USA. Historically, smooth bromegrass, timothy, reed canarygrass, and orchardgrass have been important species and they still exist in many old hay fields. Tall fescue, m...

  7. Predictors of Successful Nursing Education Outcomes: A Study of the North Carolina Central University's Nursing Program

    ERIC Educational Resources Information Center

    Ukpabi, Chinasa Victor

    2008-01-01

    The primary purpose of this study was to specify the variables that would play the greatest role in predicting success of North Carolina Central University (NCCU) nursing graduates in the National Certification Licensure Examination for Registered Nurses (NCLEX-RN). Participants for this study include a convenience sample of 39 students who…

  8. SOIL RADON POTENTIAL MAPPLING OF TWELVE COUNTIES IN NORTH-CENTRAL FLORIDA

    EPA Science Inventory

    The report describes the approach, methods, and detailed data used to prepare soil radon potential maps of 12 counties in North-Central Florida. he maps were developed under the Florida Radon Research Program to provide a scientific basis for implementing radon-protective buildin...

  9. DIGITAL GEOLOGIC MAP OF SHERMAN QUADRANGLE, NORTH CENTRAL TEXAS (CD-ROM)

    EPA Science Inventory

    This compact disc contains digital data sets of the surficial geology and geologic faults for the 1:250,000-scale Sherman quadrangle, North Central Texas, and can be used to make geologic maps, and determine approximate areas and locations of various geologic units. The source d...

  10. The State of Economic and Social Development in the North Central Region of the United States.

    ERIC Educational Resources Information Center

    Rogers, Keith D.; And Others

    Emphasizing patterns of rural economic and social activity in the North Central Region (NCR) of the U.S., this report utilizes U.S. census data to survey and analyze: population distribution; business patterns; agricultural activity; local and county government expenditures; and income distribution. Among the major findings reported are: slightly…

  11. Residual Weeds of Processing Sweet Corn in the North Central Region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge of weed community structure in vegetable crops of the North Central Region (NCR) is poor. To characterize weed composition of species persisting in sweet corn to harvest, hereafter called residual weeds, 175 sweet corn fields were surveyed in Illinois, Minnesota, and Wisconsin from 2005 to...

  12. Central North Atlantic Plate Motions over the Last 40 Million Years.

    PubMed

    Phillips, J D; Luyendyk, B P

    1970-11-13

    The relative motion vector for the North American and African plates has been determined from detailed charting of the trend of the Atlantis fracture zone for over 1000 kilometers in the central North Atlantic near 30 degrees N and from identification of marine magnetic anomalies and deep-sea drilling results. The vector (pole) is located at 52.5 degrees N, 34 degrees W and has a magnitude (opening rate) of 5.7 x 10(-7) degree per year. Major changes in either the pole location or the opening rate are not evident for the last 40 million years. PMID:17776338

  13. A seamless, high-resolution digital elevation model (DEM) of the north-central California coast

    USGS Publications Warehouse

    Foxgrover, Amy C.; Barnard, Patrick L.

    2012-01-01

    A seamless, 2-meter resolution digital elevation model (DEM) of the north-central California coast has been created from the most recent high-resolution bathymetric and topographic datasets available. The DEM extends approximately 150 kilometers along the California coastline, from Half Moon Bay north to Bodega Head. Coverage extends inland to an elevation of +20 meters and offshore to at least the 3 nautical mile limit of state waters. This report describes the procedures of DEM construction, details the input data sources, and provides the DEM for download in both ESRI Arc ASCII and GeoTIFF file formats with accompanying metadata.

  14. Subduction evolution and mantle dynamics at a continental margin: Central North Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Stern, T. A.; Stratford, W. R.; Salmon, M. L.

    2006-12-01

    Central North Island, New Zealand, provides an unusually complete geological and geophysical record of the onset and evolution of subduction at a continental margin. Whereas most subduction zones are innately two-dimensional, North Island of New Zealand displays a distinct three-dimensional character in the back-arc regions. Specifically, we observe "Mariana-type" subduction in the back-arc areas of central North Island in the sense of back-arc extension, high heat flow, prolific volcanism, geothermal activity, and active doming and exhumation of the solid surface. Evidence for emplacement of a significant percent of new lithosphere beneath the central North Island comes from heat flux of 25 MW/km of strike (of volcanic zone) and thinned crust underlain by rocks with a seismic wave speed consistent with underplated new crust. Seismic attenuation (Qp-1) is high (˜240), and rhyolitic and andesitic volcanism are widespread. Almost complete removal of mantle lithosphere is inferred here in Pliocene times on the basis of the rock uplift history and upper mantle seismic velocities as low as 7.4 ± 0.1 km/s. In contrast, southwestern North Island exhibits "Chilean-type" back-arc activity in the sense of compressive tectonics, reverse faulting, low-heat-flow, thickened lithosphere, and strong coupling between the subducted and overriding plates. This rapid switch from Mariana-type to Chilean-type subduction occurs despite the age of the subducted plate being constant under North Island. Moreover, stratigraphic evidence shows that processes that define the extensional back-arc area (the Central Volcanic Region) are advancing southward into the compressional system (Wanganui Basin) at about 10 mm/yr. We link the progression from one system to another to a gradual and viscous removal of thickened mantle lithosphere in the back-arc regions. Thickening occurred during the Miocene within the Taranaki Fault Zone. The process of thickening and convective removal is time- and

  15. The Rural School Building in North Central and Northwestern North Dakota: A Brief Description. Country School Legacy: Humanities on the Frontier.

    ERIC Educational Resources Information Center

    Carlson, Mary C.

    The time period and the pioneer conditions that existed when north central and northwestern North Dakota were settled determined the type of rural schools that were established there. Those areas were settled between 1885 and 1910. Most of the settlers in that area of the state were of Scandinavian (particularly Norwegian) extraction. The vast…

  16. Updated precipitation reconstruction (AD 1482-2012) for Huashan, north-central China

    NASA Astrophysics Data System (ADS)

    Chen, Feng; Zhang, Ruibo; Wang, Huiqin; Qin, Li; Yuan, Yujiang

    2016-02-01

    We developed a tree-ring width chronology from pine trees ( Pinus tabulaeformis and Pinus armandii) stand near the peaks of Huashan, Shaanxi, north-central China. Growth-climate response analyses showed that the radial growth of pine trees is mainly influenced by April-June precipitation. A model to reconstruct precipitation based on tree widths was constructed, accounting for 55 % of the instrumental variance during the period 1953-2012. Spatial correlation analyses between the reconstruction and observed gridded precipitation data shows that the seasonal precipitation reconstruction captures regional climatic variations over north China. Compared with the historical archives and other tree-ring records in north China, many large-scale drought events, linked to the El Niño-Southern Oscillation (ENSO), were found. Many of these events have had profound impacts on the people of north China over the past several centuries. Composite maps of sea surface temperatures and 500 hPa geopotential heights for selected extremely dry and wet years in Huashan show characteristics similar to those related to the ENSO patterns, particularly with regard to ocean and atmospheric conditions in the equatorial and north Pacific. Our 531-year precipitation reconstruction for Huashan provides a long-term perspective on current and 20th century wet and dry events in north China, and is useful to guide expectations of future variability, and helps us to address climate change.

  17. Brookian sequence well log correlation sections and occurrence of gas hydrates, north-central North Slope, Alaska

    USGS Publications Warehouse

    Lewis, Kristen A.; Collett, Timothy S.

    2013-01-01

    Gas hydrates are naturally occurring crystalline, ice-like substances that consist of natural gas molecules trapped in a solid-water lattice. Because of the compact nature of their structure, hydrates can effectively store large volumes of gas and, consequently, have been identified as a potential unconventional energy source. First recognized to exist geologically in the 1960s, significant accumulations of gas hydrate have been found throughout the world. Gas hydrate occurrence is limited to environments such as permafrost regions and subsea sediments because of the pressure and temperature conditions required for their formation and stability. Permafrost-associated gas hydrate accumulations have been discovered in many regions of the Arctic, including Russia, Canada, and the North Slope of Alaska. Gas hydrate research has a long history in northern Alaska. This research includes the drilling, coring, and well log evaluation of two gas hydrate stratigraphic test wells and two resource assessments of gas hydrates on the Alaska North Slope. Building upon these previous investigations, this report provides a summary of the pertinent well log, gas hydrate, and stratigraphic data for key wells related to gas hydrate occurrence in the north-central North Slope. The data are presented in nine well log correlation sections with 122 selected wells to provide a regional context for gas hydrate accumulations and the relation of the accumulations to key stratigraphic horizons and to the base of the ice-bearing permafrost. Also included is a well log database that lists the location, available well logs, depths, and other pertinent information for each of the wells on the correlation section.

  18. Development of neutralizing monoclonal antibodies for oncogenic human papillomavirus types 31, 33, 45, 52, and 58.

    PubMed

    Brown, Martha J; Seitz, Hanna; Towne, Victoria; Müller, Martin; Finnefrock, Adam C

    2014-04-01

    Human papillomavirus (HPV) is the etiological agent for all cervical cancers, a significant number of other anogenital cancers, and a growing number of head and neck cancers. Two licensed vaccines offer protection against the most prevalent oncogenic types, 16 and 18, responsible for approximately 70% of cervical cancer cases worldwide and one of these also offers protection against types 6 and 11, responsible for 90% of genital warts. The vaccines are comprised of recombinantly expressed major capsid proteins that self-assemble into virus-like particles (VLPs) and prevent infection by eliciting neutralizing antibodies. Adding the other frequently identified oncogenic types 31, 33, 45, 52, and 58 to a vaccine would increase the coverage against HPV-induced cancers to approximately 90%. We describe the generation and characterization of panels of monoclonal antibodies to these five additional oncogenic HPV types, and the selection of antibody pairs that were high affinity and type specific and recognized conformation-dependent neutralizing epitopes. Such characteristics make these antibodies useful tools for monitoring the production and potency of a prototype vaccine as well as monitoring vaccine-induced immune responses in the clinic. PMID:24574536

  19. Characterization of carbon in sediment-hosted disseminated gold deposits, north central Nevada

    USGS Publications Warehouse

    Leventhal, Joel; Hofstra, Albert

    1990-01-01

    The gray, dark gray and black colors of the sediments and the presence of pyrite in the Carlin, Jerritt Canyon, Horse Canyon, Betze, and Gold Acres sediment-hosted disseminated gold (SHDG) deposits indicate that these rocks are not oxidized with respect to carbon and iron sulfide. The organic matter in the host rocks of SHDG deposits in north-central Nevada is cryptocrystalline graphite with dimensions of 30 to 70 A (0.003 to 0.007 ??) that was formed at temperatures of 250 to 300??C. These results indicate that north-central Nevada was subjected to pumpellyite-actinolite to lowermost greenschist facies conditions prior to mineralization. The hydrothermal fluids that produced the gold deposits had little, if any, effect on the thermal maturity and crystallinity of the cryptocrystalline graphite produced by the earlier thermal event.

  20. Assessment of undiscovered oil and gas resources of the Sud Province, north-central Africa

    USGS Publications Warehouse

    Brownfield, M.E.; Klett, T.R.; Schenk, C.J.; Charpentier, R.R.; Cook, T.A.; Pollastro, R.M.; Tennyson, M.E.

    2011-01-01

    The Sud Province located in north-central Africa recently was assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 7.31 billion barrels of oil, 13.42 trillion cubic feet of natural gas, and 353 million barrels of natural gas liquids.

  1. Assessment of undiscovered oil and gas resources of the Chad Basin Province, North-Central Africa

    USGS Publications Warehouse

    Brownfield, Michael E.; Schenk, Christopher J.; Charpentier, Ronald R.; Klett, Timothy R.; Cook, Troy A.; Pollastro, Richard M.; Tennyson, Marilyn E.

    2010-01-01

    The Chad Basin Province located in north-central Africa recently was assessed for undiscovered, technically recoverable oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 2.32 billion barrels of oil, 14.65 trillion cubic feet of natural gas, and 391 million barrels of natural gas liquids.

  2. Acid deposition and air quality related values in north central Colorado wilderness areas. Final report

    SciTech Connect

    Hidy, G.M.

    1995-05-01

    Terrestrial and aquatic ecosystem response to atmospheric acid, sulfur, and nitrate deposition has been studied only in a very limited way in Colorado wilderness areas. However, the observed deposition rates in north central Colorado remain low relative to affected areas in the eastern United States and well within a range where no adverse ecological effects are expected. This report presents a survey of scientific information describing acid deposition and air quality related values, which may have implications for utility plant operations.

  3. Genetic and morphological divergence among Cooper's Hawk (Accipiter cooperii) populations breeding in north-central and western North America

    USGS Publications Warehouse

    Sonsthagen, Sarah A.; Rosenfield, Robert N.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William C.; Driscoll, Timothy G.; Bozek, Michael A.; Sloss, Brian L.; Talbot, Sandra L.

    2012-01-01

    Cooper's Hawk (Accipiter cooperii) populations breeding in the northern portion of the species' range exhibit variation in morphological traits that conforms to predictions based on differences in prey size, tree stand density, and migratory behavior. We examined genetic structure and gene flow and compared divergence at morphological traits (PST) and genetic markers (FST) to elucidate mechanisms (selection or genetic drift) that promote morphological diversification among Cooper's Hawk populations. Cooper's Hawks appear to conform to the genetic pattern of an east-west divide. Populations in British Columbia are genetically differentiated from north-central populations (Wisconsin, Minnesota, and North Dakota; pairwise microsatellite FST= 0.031-0.050; mitochondrial DNA ΦST = 0.177-0.204), which suggests that Cooper's Hawks were restricted to at least two Pleistocene glacial refugia. The strength of the Rocky Mountains—Great Plains area as a barrier to dispersal is further supported by restricted gene-flow rates between British Columbia and other sampled breeding populations. Divergence in morphological traits (PST) was also observed across study areas, but with British Columbia and North Dakota differentiated from Wisconsin and Minnesota, a pattern not predicted on the basis of FST and ΦST interpopulation estimates. Comparison of PSTand FSTestimates suggests that heterogeneous selection may be acting on Cooper's Hawks in the northern portion of their distribution, which is consistent with hypotheses that variation in prey mass and migratory behavior among populations may be influencing overall body size and wing chord. We were unable to distinguish between the effects of genetic drift and selection on tail length in the study populations.

  4. Is the Central America forearc sliver part of the North America plate?

    NASA Astrophysics Data System (ADS)

    Guzman-Speziale, M.

    2012-04-01

    The Central America Forearc sliver is located between the Central America volcanic arc and the Middle America trench. Several authors have suggested that the forearc is being displaced to the northwest with respect to the Caribbean plate; they point to right-lateral, normal-faulting earthquakes along the Central America volcanic arc as prime evidence of this displacement. Apparently, the forearc continues to the northwest into southeastern Mexico, although this portion of the forearc is not being displaced. I present evidence that suggests that the forearc indeed continues into southeastern Mexico and that it belongs to the North America plate. Physiographically, there is a continuity of the forearc into the Coastal plains of southeastern (Chiapas) Mexico, across the Motagua and Polochic faults. Offshore, cross-sections of the Middle America trench are similar along the mexican (Chiapas) segment, and the Central American segment. Furthermore, at the northwestern end of the coastal plain there are no compressive structures, which suggests that the coastal plain is not being displaced to the northwest. As a matter of fact, fault-plane solutions for shallow earthquakes show extension rather than compression. Shallow, interplate earthquakes along the trench show similar parameters along both segments. P-axes and earthquake slip vectors have consistent azimuths, which relate better with Cocos-North America convergence than with Cocos-Caribbean. Azimuth of T-axes for normal-faulting earthquakes also agree well with Cocos-North America convergence. Similarity in several parameters is thus found across both segments, the Chiapas coastal plain and the Central America forearc sliver proper. This suggests that both segments are continuous and probably one and the same, and belonging to the North America plate. Perhaps more properly, the forearc sliver extends into southeastern Mexico and is part of the zone of deformation associated to the Cocos-North America-Caribbean plates

  5. Herbarium specimens reveal the footprint of climate change on flowering trends across north-central North America.

    PubMed

    Calinger, Kellen M; Queenborough, Simon; Curtis, Peter S

    2013-08-01

    Shifting flowering phenology with rising temperatures is occurring worldwide, but the rarity of co-occurring long-term observational and temperature records has hindered the evaluation of phenological responsiveness in many species and across large spatial scales. We used herbarium specimens combined with historic temperature data to examine the impact of climate change on flowering trends in 141 species collected across 116,000 km(2) in north-central North America. On average, date of maximum flowering advanced 2.4 days °C(-1), although species-specific responses varied from - 13.5 to + 7.3 days °C(-1). Plant functional types exhibited distinct patterns of phenological responsiveness with significant differences between native and introduced species, among flowering seasons, and between wind- and biotically pollinated species. This study is the first to assess large-scale patterns of phenological responsiveness with broad species representation and is an important step towards understanding current and future impacts of climate change on species performance and biodiversity. PMID:23786499

  6. Environmental sampling reveals that Pythium insidiosum is ubiquitous and genetically diverse in North Central Florida.

    PubMed

    Presser, Jackson W; Goss, Erica M

    2015-09-01

    Pythiosis is a deadly disease of horses, dogs, and other mammals, including humans, in tropical and subtropical regions. In the United States, the disease has been reported in the Southeast as well as in the temperate North and the dry Southwest. The causal agent of pythiosis is Pythium insidiosum, one of few mammalian pathogens in the fungus-like Oomycetes. P. insidiosum has not been studied in the environment in the United States. Given anecdotal reports of pythiosis in Gainesville, Florida dogs, we hypothesized that warm standing water in lakes and ponds in North Central Florida is suitable habitat for P. insidiosum. We sampled 19 lakes or ponds to examine the environmental distribution of P. insidiosum and to determine which of the three previously described genetic clusters of P. insidiosum are present. We found P. insidiosum in 11 of the sampled lakes and ponds. Sequencing of the ITS region separated isolates into three genetic clusters, including a distinct group previously represented by a single isolate from South Carolina. AFLP genotyping of isolates showed genetic variation in Cluster I, which is the group associated with the majority of characterized clinical isolates from the Americas. Our results indicate that animal exposure to P. insidiosum in North Central Florida is common. This study provides the first evidence that P. insidiosum may be more widely distributed in freshwater lakes and ponds in the Southeastern United States than previously appreciated. PMID:26229152

  7. Moho geometry along a north-south passive seismic transect through Central Australia

    NASA Astrophysics Data System (ADS)

    Sippl, Christian

    2016-04-01

    Receiver functions from a temporary deployment of 25 broadband stations along a north-south transect through Central Australia are used to retrieve crustal and uppermost mantle structural constraints from a combination of different methods. Using H-K stacking as well as receiver function inversion, overall thick crust with significant thickness variation along the profile (40 to ≥ 55 km) is found. Bulk crustal vp/vs values are largely in the felsic to intermediate range, with the southernmost stations on the Gawler Craton exhibiting higher values in excess of 1.8. A common conversion point (CCP) stacking profile shows three major discontinuities of the crust-mantle boundary: (1) a two-sided Moho downwarp beneath the Musgrave Province, which has previously been associated with the Neoproterozoic to early Cambrian Petermann Orogeny, (2) a Moho offset along the Redbank Shear Zone further north attributed to the Middle to Late Paleozoic Alice Springs Orogeny, and (3) another Moho offset further north, located at the boundary between the Davenport and Warramunga Provinces, which has not been imaged before. In all cases, the difference in crustal thickness between the two sides of the offset is > 8-10 km. Unlike the two southern Moho offsets, the northernmost one does not coincide with a prominent gravity anomaly. Its location and the absence of known reactivation events in the region make it likely that it belongs to a Proterozoic suture zone that marks a previously unknown block boundary within the North Australian Craton.

  8. Faulting patterns in north-central Nevada and strength of the crust

    SciTech Connect

    Zoback, M.D.; Zoback, M.L.

    1980-01-10

    North-northeast normal fault trends characterize much of the N. basin and range province. These faults make sharp bends to north-northwest and east-northeast trends in N.-central Nevada in the vicinity of a Mid-Miocene rift characterized by a zone of diabase dike swarms, graben-filling flows, and a coinciding aeromagnetic anomaly. Despite a roughly 45 change in the least principal stress direction since Mid-Miocene time, pre-existing north-northwest- and east-northeast-trending faults in the vicinity of the rift accommodated the extension whereas regionally, major crustal blocks were faulted along a north-northeast trend, approximately perpendicular to the modern least principal stress direction. An assumed uniform regional stress field (derived from geologic and geophysical indicators of the modern principal stress field) and the observed oblique slip on the preexisting faults were combined in an analysis utilizing an empirically derived frictional sliding law and the Coulomb failure criterion. 27 references.

  9. Intrusion of radioactive industrially polluted water from North Sea into central Baltic Sea

    SciTech Connect

    Vakulovskiy, S.M.; Nikitin, A.I.

    1985-02-01

    The problem of penetration of radioactive industrially polluted water into the central Baltic Sea was studied. The content of Cs-134 as determined in water near the bottom of deep water trenches along the path traveled by North Sea water entering the Baltic. Samples were taken at 5 locations, with Cs-134 concentrated from samples of several thousands of liters. It was found that radioactive pollution caused by the entry of water from the North Sea extends through the system of deep water depressions into the Baltic as far as the Gotland trench. The greatest degree of contamination is found in the Arkona depression adjacent to the straits. The concentration of Cs-134 in the Gdansk trench is one-half as great and in the Gotland trench one-third as great as in the Arkona depression. Radioactive contamination in the Baltic is attributed to discharge of radioactive wastes by plants at Windscale.

  10. Plio-Pleistocene changes in the vegetation of central North Africa

    NASA Astrophysics Data System (ADS)

    Castaneda, I. S.; Phu, V.; Urann, B.

    2013-12-01

    The area of central North Africa (including the Sahara and the Sahel) is sensitive to migrations of the intertropical rainbelt and has experienced dramatic, and possibly abrupt, shifts between wet and arid conditions in the past. For example, during the humid period of the early Holocene, the region that is presently the Sahara desert was vegetated and contained permanent lakes, and was occupied by human populations (e.g. Kuper and Kröpelin, 2006). In this study, we investigate the hydrology of central North Africa during the Plio-Pleistocene (4-0.5 Ma), a period during which a number of key steps in hominin evolution occurred. ODP site 660 is located in the tropical NE Atlantic Ocean (offshore West Africa) and receives dust from central North Africa, which is transported offshore by the African Easterly Jet. Plant leaf waxes (n-alkanes) contained in this dust provide information on the type of vegetation present , which in turn, can be used to examine hydrological variability because in tropical Africa the large scale distribution of vegetation utilizing the C3 (mainly trees) vs. C4 (grasses and warm season sedges) photosynthetic pathways mainly depends on aridity (precipitation) (e.g. Schefuss et al., 2003). Here, we examine the carbon (δ13C) and deuterium (δD) isotopic composition of plant leaf waxes, proxies for vegetation type (C3 vs. C4 plants) and precipitation amount, respectively. We also examine sea surface temperature variability using the alkenone Uk'37 Index as several studies have demonstrated close ties between sea surface temperature variability and hydrological conditions in N Africa during the late Pleistocene and Holocene. Results of this study further support a close link between SST and hydrological conditions in the Sahel during the past 4 Ma while also highlighting regional differences in aridity between Plio-Pleistocene records of western, eastern and southern Africa.

  11. Evaluating regional differences in macroinvertebrate communities from forested depressional wetlands across eastern and central North America.

    SciTech Connect

    Batzer, Darold, P.; Dietz-Brantley, Susan E.; Taylor, Barbera E.; DeBiase, Adrienne E.

    2005-02-12

    Batzer, Darold, P., Susan E. Dietz-Brantley, Barbera E. Taylor, and Adrienne E. DeBiase. 2005. Evaluating regional differences in macroinvertebrate communities from forested depressional wetlands across eastern and central North America. J. N. Am. Benthol. Soc. 24(2):403-414. Abstract. Forested depressional wetlands are an important seasonal wetland type across eastern and central North America. Macroinvertebrates are crucial ecosystem components of most forested depressional wetlands, but community compositions can vary widely across the region. We evaluated variation in macroinvertebrate faunas across eastern and central North America using 5 published taxa lists from forested depressional wetlands in Michigan, Ontario, Wisconsin, Florida, and Georgia. We supplemented those data with quantitative community descriptions generated from 17 forested depressional wetlands in South Carolina and 74 of these wetlands in Minnesota. Cluster analysis of presence/absence data from these 7 locations indicated that distinct macroinvertebrate communities existed in northern and southern areas. Taxa characteristic of northern forested depressionalwetlands included Sphaeriidae, Lumbriculidae, Lymnaeidae, Physidae, Limnephilidae, Chirocephalidae, and Hirudinea (Glossophoniidae and/or Erpodbellidae) and taxa characteristic of southern sites included Asellidae, Crangonyctidae, Noteridae, and Cambaridae. Quantitative sampling in South Carolina and Minnesota indicated that regionally characteristic taxa included some of the most abundant organisms, with Sphaeriidae being the 2nd most abundant macroinvertebrate in Minnesota wetlands and Asellidae being the 2nd most abundant macroinvertebrate in South Carolina wetlands. Mollusks, in general, were restricted to forested depressional wetlands of northern latitudes, a pattern that may reflect a lack of Ca needed for shell formation in acidic southern sites. Differences in community composition probably translate into region

  12. Arctic-Asian Mobile Belt - Global Structure in the North, Central, and East Asia

    NASA Astrophysics Data System (ADS)

    Shokalsky, Sergey; Petrov, Oleg; Pospelov, Igor; Kashubin, Sergey; Sobolev, Nikolay; Petrov, Evgeny

    2014-05-01

    Over the last decade under the international project of five countries, the geological surveys of Russia, China, Kazakhstan, Mongolia, and the Republic of Korea, with the participation of national academies of sciences in these countries compiled a set of digital maps at 1:2.5 M scale. It includes geological, tectonic, metallogenic maps and map of energy resources with databases for North, Central, and East Asia, area of more than 30 million km2. Map compilation was supervised by the Subcommission for Northern Eurasia and Subcommission for Tectonic Maps of the Commission for the Geological Map of the World under the auspices of UNESCO (CGMW). The set of maps was displayed at the 33rd IGC (Oslo, 2008) and 34th IGC (Brisbane, 2012). One of the largest accretion collages of orogenic belts of different ages on the planet (from the Neoproterozoic to Early Mesozoic) is clearly shown in the tectonic map compiled under the joint project. Extended polychronous mobile belt is bounded in the west by the East European Craton, in the east, by the Siberian Craton, in the south, by a chain of Gondwana cratonic blocks - North China, Tarim, Tajik. In the north it can be traced as a broad band within the Circumpolar Region, where it is limited by the North American Craton. The central part of the accretionary belt is hidden under the Meso-Cenozoic sediments of Western Siberia. Analysis of vast geological material shows that the Arctic-Asian mobile belt was formed on place of an extensive paleo-ocean, which closed with a successive rejuvenation of suture ophiolite zones from the marginal to axial zone and along strike to the north and east of the South Siberian segment towards Paleopacific. Arctic-Asian mobile belt is characterized by a complex combination of accretionary and riftogenic tectonic-magmatic processes. At its early stages, accretionary tectonics with a wide development of volcanic belts dominated; at the late ones (in the Late Paleozoic, Mesozoic, and Cenozoic

  13. Hydrology and geochemistry of thermal ground water in southwestern Idaho and north-central Nevada

    SciTech Connect

    Young, H.W.; Lewis, R.E.

    1980-12-01

    The study area occupies about 14,500 square miles in southwestern Idaho and north-central Nevada. Thermal ground water occurs under artesian conditions, in discontinuous or compartmented zones, in igneous or sedimentary rocks of Tertiary age. Ground-water movement is generally northward. Temperatures of the ground water range from about 30/sup 0/ to more than 80/sup 0/C. Chemical analyses of water from 12 wells and 9 springs indicate that nonthermal waters are a calcium bicarbonate type; thermal waters are a sodium bicarbonate type. Chemical geothermometers indicate probable maximum reservoir temperatures are near 100/sup 0/C. Concentration of tritium in the thermal water water is near zero.

  14. Geohydrologic data from the Jemez Mountains and vicinity, north-central New Mexico

    USGS Publications Warehouse

    Trainer, Frank W.

    1978-01-01

    The Jemez Mountains volcanic region, on the west margin of the Rio Grande rift in north-central New Mexico, is the site of studies for power development from geothermal heat. This report summarizes geohydrologic data to provide background information relative to the geothermal exploration and to investigate the usefulness of hydrology in assessment of the geothermal resource. Eleven tables present chemical, temperature, discharge , and other data for springs, wells, and streams. Accompanying figures show locations of the data points and present temperature profiles and geophysical logs for selected wells. (Woodard-USGS)

  15. Estimates of Internal Tide Energy Fluxes from Topex/Poseidon Altimetry: Central North Pacific

    NASA Technical Reports Server (NTRS)

    Ray, Richard D.; Cartwright, David E.; Smith, David E. (Technical Monitor)

    2000-01-01

    Energy fluxes for first-mode M(sub 2) internal tides are deduced throughout the central North Pacific Ocean from Topex/Poseidon satellite altimeter data. Temporally coherent internal tide signals in the altimetry, combined with climatological hydrographic data, determine the tidal displacements, pressures, and currents at depth, which yield power transmission rates. For a variety of reasons the deduced rates should be considered lower bounds. Internal tides were found to emanate from several large bathymetric structures, especially the Hawaiian Ridge, where the integrated flux amounts to about six gigawatts. Internal tides are generated at the Aleutian Trench near 172 deg west and propagate southwards nearly 2000 km.

  16. Linear relation of central and eastern North American precipitation to tropical Pacific Sea surface temperature anomalies

    SciTech Connect

    Montroy, D.L.

    1997-04-01

    In past research the Southern Oscillation index has often been used as an indicator of the tropical Pacific climate, notably for El Nino and La Nina event occurrences. This study identifies calendar monthly teleconnection signals in central and eastern North American precipitation associated with an alternative tropical Pacific indicator, sea surface temperature anomaly (SSTA) patterns. Using an approximate 1{degrees} resolution set of monthly precipitation totals for 1950-92, the work identifies monthly teleconnection relationships and their intraseasonal evolution. This builds upon previous studies that were limited to seasonal timescales. Here, a unique two-way statistical analysis is used to delineate linear SSTA-precipitation teleconnection patterns.

  17. Morphometric changes in Yellow-headed Blackbirds during summer in central North Dakota

    USGS Publications Warehouse

    Twedt, D.J.; Linz, G.M.

    2002-01-01

    Temporal stability of morphometric measurements is desirable when using avian morphology as a predictor of geographic origin. Therefore, to assess their temporal stability, we examined changes in morphology of Yellow-headed Blackbirds (Xanthocephalus xanthocephalus) from central North Dakota during summer. Measurements differed among age classes and between sexes. As expected, due to growth and maturation, measurements on hatching-year birds increased over summer. Measurements of adult plumage fluctuated with prebasic molt and exhibited age-specific discontinuities. Body mass of adult birds increased over summer, whereas both culmen length and skull length decreased. Only body length and length of internal skeletal elements were temporally stable in adult Yellow-headed Blackbirds.

  18. Unretrieved shooting loss of mourning doves in north-central South Carolina

    USGS Publications Warehouse

    Haas, G.H.

    1977-01-01

    Unretrieved loss for mourning doves (Zenaida macroura) in north-central South Carolina was between 27 and 41 percent of the retrieved kill for the 1973 through 1975 hunting seasons based on 1,396 doves shot by 281 hunters. Dove hunters hunted in groups, fired 8.6 shots per retrieved dove, and engaged in a substantial number of illegal activities. Increased dove populations and hunter bag resulted in increased unretrieved loss, numbers of shots per bagged bird, and illegal activities. Retriever dogs increased the efficiency of dove hunters.

  19. A preliminary classification of wetland plant communities in north-central Minnesota

    USGS Publications Warehouse

    Cowardin, L.M.; Johnson, D.H.

    1973-01-01

    A classification of wetland plant communities was developed for a study area in north-central Minnesota in order to analyze data on waterfowl use of habitat that were gathered by radio telemetry. The classification employs features of several earlier classifications in addition to new classes for bogs and lakeshore communities. Brief descriptions are given for each community, and the important plant species are listed. Discriminant function analysis was used for 40 plant species. Seventy-five percent of the stands studied were classified correctly by this technique. Average probabilities of assignment to communities were calculated and helped to identify distinct and poorly defined communities as well as the relationship among communities.

  20. The interdependence of lake ice and climate in central North America

    NASA Technical Reports Server (NTRS)

    Jelacic, A. J. (Principal Investigator)

    1972-01-01

    There are no author-identified significant results in this report. This investigation is to identify any correlations between the freeze/ thaw cycles of lakes and regional weather variations. ERTS-1 imagery of central Canada and north central United States is examined on a seasonal basis. The ice conditions of certain major study lakes are noted and recorded on magnetic tape, from which the movement of a freeze/thaw transition zone may be deduced. Weather maps and tables are used to establish any obvious correlations. The process of selecting major study lakes is discussed, and a complete lake directory is presented. Various routines of the software support library are described, accompanied by output samples. Procedures used for ERTS imagery processing are presented along with the data analysis plan. Application of these procedures to selected ERTS imagery has demonstrated their utility. Preliminary results show that the freeze/thaw transition zone can be monitored from ERTS.

  1. Knowledge-based soil inference modeling for estimating soil productivity and grain yield in north-central Missouri

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We used ArcSIE (Soil Inference Engine) software to model soils resembling those mapped by NRCS soil survey, for eight 12-digit watersheds in the Central Claypan (MLRA113) in north-central Missouri. Our source data for modeling was the 10m USGS Digital Elevation Model. Environmental Covariates used i...

  2. A geologic history of the north-central Appalachians, part 3. The Alleghany orogeny

    USGS Publications Warehouse

    Faill, R.T.

    1998-01-01

    The north-central Appalachians occupy a critical position within the 3000+ km-long Appalachian orogen, lying southwest of the boundary between the central and northern Appalachians (CNAB). The one-billion-year-long history of tectonic activity in eastern Laurentia includes the creation and evolution of the Appalachian orogen during the Paleozoic and the Mesozoic transformation of the orogen into a passive margin during Pangea's disassembly. A most important ingredient in the evolution of the orogen was the Alleghany orogeny, which was driven by the convergence and collision between Laurentia (Laurussia) and West Gondwana (Africa). The Alleghany orogeny in the central and southern Appalachians was a de??collement tectonism that involved a larger part of eastern Laurentia than had the previous three orogenies. The fundamental element was a very low-angle thrust (de??collement) that originated in mid-crustal levels east of the presently-exposed Appalachians and rose westwardly to progressively higher levels in the upper crust and the supra-crustal Paleozoic section. Alleghany deformation was widely developed in the hanging-wall block (allochthon), primarily in the form of thrust faults and fold-and-thrust structures, both of which splayed upward from the basal de??collement. The youngest manifestations of the Alleghany orogeny were northeast-trending strike-slip faults and dextral shear zones in the Piedmont. In the north-central Appalachians, the exposed allochthon consists of two parts: the sedimentary externides (Appalachian Plateau and Valley and Ridge provinces) and the crystalline externides (Reading Prong, Blue Ridge belt, and Piedmont province). Long, thrust-cored anticlines predominate in the sedimentary externides. A widespread layer-parallel shortening preceded the folding; it is largely coaxial with the folding but extends considerably farther to the northwest toward the craton. It is hypothesized that the folding developed in reverse order, sequentially

  3. Seismic Attenuation, Temperature, H20, Mantle Melting and Rock Uplift, Central North Island New Zealand

    NASA Astrophysics Data System (ADS)

    Salmon, M.; Savage, M.; Stern, T.

    2005-12-01

    Back-arc basins of the western Pacific are elevated some 1-2 km above the adjacent oceanic floor. Where oceanic back-arc basins propagate into continental lithosphere we also see an uplift signal, which can be mapped and evaluated with geological methods. Trying to understand the driving force for this uplift requires seismological methods to quantify temperatures, and therefore buoyancy, in the upper mantle. New Zealand's North Island is one such place where the back-arc basin has propagated into continental lithosphere. Geological records show that the North Island has undergone up to 2.5 km of broad wavelength rock uplift since 5 Ma. We use earthquake data to map variations in seismic attenuation (Qp-1) beneath the North Island. Results are used to determine some constraints on the effects of temperature, water and melt on buoyancy in the mantle wedge above the subduction zone. A region of high attenuation extending to depths of ~140 km correlates, spatially, with the region of back-arc extension, volcanism and high heat flow (Central Volcanic Region or CVR). In this region the path-averaged Qp-1 for frequencies from 1-15Hz is 4.0×10-3±0.3×10-3 and shows little variation with depth. West of the CVR, the north-western North Island shows a decrease in attenuation but Qp-1 remains slightly elevated (path-averaged Qp-1 1.4×10-3±0.2×10-3). Here attenuation increases with depth until it reaches similar values as the CVR mantle at approximately 80 km. We use Qp values to calculate temperatures at 30 km and 80 km depth below these two regions. Temperatures at 30 km below the CVR are elevated to just above the melting temperature (1.02 Tm) while to the west temperatures are just below the solidus (~0.95 Tm). At 80 km depth attenuation indicates temperatures for both regions are just above the solidus. To reconcile temperatures calculated from heat flow measurements in the north-western North Island with those calculated from attenuation, melting temperatures must

  4. Avian use of Sheyenne Lake and associated habitats in central North Dakota

    USGS Publications Warehouse

    Faanes, C.A.

    1982-01-01

    A study of avian use of various habitats was conducted in the Sheyenne Lake region of central North Dakota during April-June 1980. Population counts of birds were made in wetlands of various classes, prairie thickets, upland native prairie, shelterbelts, and cropland. About 22,000 breeding bird pairs including 92 species that nested occupied the area. Population means for most species were equal to or greater than statewide means. Red-winged blackbird (Agelaius phoeniceus), yellow-headed blackbird (Xanthocephalus xanthocephalus), mourning dove (Zenaida macroura), and blue-winged teal (Anas discors) were the most numerous species, and made up 32.9% of the total population . Highest densities of breeding birds occurred in shelterbelts, semipermanent wetlands, and prairie thickets. Lowest densities occurred in upland native prairie and cropland. The study area was used by 49.6% of the total avifauna of the State, and 51% of the breeding avifauna of North Dakota probably nested in the study area. The diversity of birds using the area was unusual in that such a large number of species occupied a relatively small area. The close interspersion of many native habitats, several of which are unique in North Dakota, probably accounted for this diversity. Data on dates of occurrence, nesting records, and habitat use are presented for the 175 species recorded in 1980. Observations of significance by refuge staff are also provided.

  5. A synoptic climatology of derecho producing mesoscale convective systems in the North-Central Plains

    NASA Astrophysics Data System (ADS)

    Bentley, Mace L.; Mote, Thomas L.; Byrd, Stephen F.

    2000-09-01

    Synoptic-scale environments favourable for producing derechos, or widespread convectively induced windstorms, in the North-Central Plains are examined with the goal of providing pattern-recognition/diagnosis techniques. Fifteen derechos were identified across the North-Central Plains region during 1986-1995. The synoptic environment at the initiation, mid-point and decay of each derecho was then evaluated using surface, upper-air and National Center for Atmospheric Research (NCAR)/National Center for Environmental Prediction (NCEP) reanalysis datasets.Results suggest that the synoptic environment is critical in maintaining derecho producing mesoscale convective systems (DMCSs). The synoptic environment in place downstream of the MCS initiation region determines the movement and potential strength of the system. Circulation around surface low pressure increased the instability gradient and maximized leading edge convergence in the initiation region of nearly all events regardless of DMCS location or movement. Other commonalities in the environments of these events include the presence of a weak thermal boundary, high convective instability and a layer of dry low-to-mid-tropospheric air. Of the two corridors sampled, northeastward moving derechos tend to initiate east of synoptic-scale troughs, while southeastward moving derechos form on the northeast periphery of a synoptic-scale ridge. Other differences between these two DMCS events are also discussed.

  6. Duripan effect on soil water availability: study case in North-Central Namibia

    NASA Astrophysics Data System (ADS)

    Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus J.

    2016-04-01

    Soils with duripan and other hardpans are frequently disregarded for agriculture. However, in North-Central Namibia, farmers cultivate a type of sandy soil with a developing duripan at few decimetres of depth. This soil is particularly valuable for Pearl Millet cultivation during years with limited rainfall. Understanding the water dynamic and the role of the duripan in the soil moisture dynamic will improve livelihood and secure food production in North-Central Namibia, in Southern Angola and other areas in the world where similar soils appear. We recorded soil water content during five months at different depth in one of these sandy soil. The comparison of the recorded data with values calculated with models based on e.g. texture indicate that the duripan plays a very important role as water reservoir. Our results demonstrate that soils with duripans should not be disregarded for agricultural development, especially in context with irregular rainfall patterns. Understanding the role of duripans based on this study will thus help to anticipate and alleviate the effect of climate change in northern Namibia and other semi-arid regions, where similar soils occur.

  7. Land use and land cover change in the North Central Appalachians ecoregion

    USGS Publications Warehouse

    Napton, D.E.; Sohl, T.L.; Auch, R.F.; Loveland, T.R.

    2003-01-01

    The North Central Appalachians ecoregion, spanning northern Pennsylvania and southern New York, has a long history of land use and land cover change. Turn-of-the-century logging dramatically altered the natural landscape of the ecoregion, but subsequent regeneration returned the ecoregion to a forest dominated condition. To understand contemporary land use and land cover changes, the U.S. Geological Survey with NASA and the U.S. Environmental Protection Agency used a random sample of satellite remotely sensed data for 1973, 1980, 1986, 1992, and 2000 to estimate the rates and assess the primary drivers of change in the North Central Appalachians. The overall change was 6.2%. The 1973-1980 period had the lowest rate of change (1.5%); the highest rate (2.9%) occurred during the 1992-2000 period. The primary conversions were deforestation through harvesting and natural disturbance (i.e., tornados) followed by regeneration, and conversion of forests to mining and urban lands. The primary drivers of the change included changes in access, energy and forest prices, and attitudes toward the environment.

  8. Late Triassic to middle Jurassic history of the north-central high Atlas, Morocco

    SciTech Connect

    Letsch, D.K.

    1988-02-01

    The Lower and Middle Jurassic (Liassic and Dogger) rocks in the north-central High Atlas and on the adjacent Oran Meseta, Morocco, were deposited on the subsiding margin of the Triassic/Jurassic High Atlas trough. This and the Middle Atlas trough formed as a result of rifting of the Moroccan Meseta and oran Meseta from the Saharan craton during initial stages of the opening of the modern Atlantic. The Tethys seaway flooded these troughs in the early Liassic, resulting in deposition of several thousand meters of liassic and Dogger limestone and marlstone. The deepening-upward Liassic section in the north-central High Atlas reflects the rapid development of the short-lived High Atlas trough, which formed in the Late Triassic-Early Liassic flooding by the Tethys established carbonate tidal flats on the Oran Meseta, a shelf margin at the basin's edge, and slope and basin-floor deposition within the trough. Rapid subsidence of the margin brought slope and basin floor sediments on top of the platform margin as the trough developed. Subsidence slowed toward the end of the Lias, resulting in progradation of the shelf-margin environments. At the end of the Lias, a portion of the margin slid into the basin, followed by debris shed off the slide scar. Continued marlstone and limestone deposition filled the basin during the Dogger, marking the end of rift-related sedimentation in the High Atlas trough.

  9. Roaming Earthquakes in North China and Central-Eastern US: How and Why?

    NASA Astrophysics Data System (ADS)

    Liu, M.; Stein, S. A.; Wang, H.

    2014-12-01

    Large earthquakes in mid-continents often occur in unexpected places. In North China, large earthquakes roamed between distant fault systems in the past 2000 years such that no large events ruptured the same fault segment twice during this period. In the central-eastern US, although historic earthquake records only go back a few hundred years, increasing paleoseismic evidence reveals large events in places of little seismicity today. Such spatiotemporal patterns of mid-continental earthquakes differ significantly from those at plate boundary zones, where relative plate motion loads the plate boundary faults steadily at relatively high rates, leading to localized seismicity with some arguable quasi-periodicity. In mid-continents, tectonic loading is slow and accommodated collectively by a complex system of interacting faults, each of which can be active for a short period after long dormancy. The mechanics of fault interaction in mid-continents remain to be fully understood. Besides the well studied Coulomb stress perturbations due to dislocation on the fault planes, property changes of fault zones by a large rupture may cause redistribution of regional stress and strain fields in mid-continents. Further studies of fault interaction and the resulting spatiotemporal occurrence of large earthquakes in mid-continents are imperative for improving earthquake hazard assessment in North China, central-eastern US, and other highly populated and earthquake-prone mid-continents.

  10. Lithologic subsurface correlation in the "Bend series" of north-central Texas

    USGS Publications Warehouse

    Goldman, M.I.

    1922-01-01

    This paper presents the results of an attempt to obtain, by a study of well drillings, criteria for correlation, by the character of the beds encountered, of horizons in the "Bend series" of north-central Texas.  The result of the work most directly applicable to the needs of the oil-well operator is that of enabling him to know more exactly the position of the producing beds in his well- a result that is of particular value in north-central Texas because certain beds in that region which give no show of oil to the drill may on being "shot" yield considerable oil.  To know the part of the stratigraphic section reached by the drill at any stage of the boring also enables the driller to be on the alert for indications of oil at horizons where productive sands are encountaered in other wells and to know when the drill has passed all horizons at which the beds are likely to yield oil.

  11. Proterozoic metamorphism and uplift history of the north-central Laramie Mountains, Wyoming, USA

    USGS Publications Warehouse

    Patel, S.C.; Frost, B.R.; Chamberlain, K.R.; Snyder, G.L.

    1999-01-01

    The Laramie Mountains of south-eastern Wyoming contain two metamorphic domains that are separated by the 1.76 Ga. Laramie Peak shear zone (LPSZ). South of the LPSZ lies the Palmer Canyon block, where apatite U-Pb ages are c. 1745 Ma and the rocks have undergone Proterozoic kyanite-grade Barrovian metamorphism. In contrast, in the Laramie Peak block, north of the shear zone, the U-Pb apatite ages are 2.4-2.1 Ga, the granitic rocks are unmetamorphosed and supracrustal rocks record only low-T amphibolite facies metamorphism that is Archean in age. Peak mineral assemblages in the Palmer Canyon block include (a) quartz-biotite-plagioclase-garnet-staurolite-kyanite in the pelitic schists; (b) quartz-biotite-plagioclase-low-Ca amphiboles-kyanite in Mg-Al-rich schists, and locally (c) hornblende-plagioclase-garnet in amphibolites. All rock types show abundant textural evidence of decompression and retrograde re-equilibration. Notable among the texturally late minerals are cordierite and sapphirine, which occur in coronas around kyanite in Mg-Al-rich schists. Thermobarometry from texturally early and late assemblages for samples from different areas within the Palmer Canyon block define decompression from > 7 kbar to < 3 kbar. The high-pressure regional metamorphism is interpreted to be a response to thrusting associated with the Medicine Bow orogeny at c. 1.78-1.76 Ga. At this time, the north-central Laramie Range was tectonically thickened by as much as 12 km. This crustal thickening extended for more than 60 km north of the Cheyenne belt in southern Wyoming. Late in the orogenic cycle, rocks of the Palmer Canyon block were uplifted and unroofed as the result of transpression along the Laramie Peak shear zone to produce the widespread decompression textures. The Proterozoic tectonic history of the central Laramie Range is similar to exhumation that accompanied late-orogenic oblique convergence in many Phanerozoic orogenic belts.

  12. What Maintains the Central North Pacific Genetic Discontinuity in Pacific Herring?

    PubMed Central

    Liu, Ming; Lin, Longshan; Gao, Tianxiang; Yanagimoto, Takashi; Sakurai, Yasunori; Grant, W. Stewart

    2012-01-01

    Pacific herring show an abrupt genetic discontinuity in the central North Pacific that represents secondary contact between refuge populations previously isolated during Pleistocene glaciations. Paradoxically, high levels of gene flow produce genetic homogeneity among ocean-type populations within each group. Here, we surveyed variability in mtDNA control-region sequences (463 bp) and nine microsatellite loci in Pacific herring from sites across the North Pacific to further explore the nature of the genetic discontinuity around the Alaska Peninsula. Consistent with previous studies, little divergence (ΦST  = 0.011) was detected between ocean-type populations of Pacific herring in the North West Pacific, except for a population in the Yellow Sea (ΦST  = 0.065). A moderate reduction in genetic diversity for both mtDNA and microsatellites in the Yellow Sea likely reflects founder effects during the last colonization of this sea. Reciprocal monophyly between divergent mtDNA lineages (ΦST  = 0.391) across the Alaska Peninsula defines the discontinuity across the North Pacific. However, microsatellites did not show a strong break, as eastern Bering Sea (EBS) herring were more closely related to NE Pacific than to NW Pacific herring. This discordance between mtDNA and microsatellites may be due to microsatellite allelic convergence or to sex-biased dispersal across the secondary contact zone. The sharp discontinuity between Pacific herring populations may be maintained by high-density blocking, competitive exclusion or hybrid inferiority. PMID:23300525

  13. The Last Glacial Maximum in the central North Island, New Zealand: palaeoclimate inferences from glacier modelling

    NASA Astrophysics Data System (ADS)

    Eaves, Shaun R.; Mackintosh, Andrew N.; Anderson, Brian M.; Doughty, Alice M.; Townsend, Dougal B.; Conway, Chris E.; Winckler, Gisela; Schaefer, Joerg M.; Leonard, Graham S.; Calvert, Andrew T.

    2016-04-01

    Quantitative palaeoclimate reconstructions provide data for evaluating the mechanisms of past, natural climate variability. Geometries of former mountain glaciers, constrained by moraine mapping, afford the opportunity to reconstruct palaeoclimate, due to the close relationship between ice extent and local climate. In this study, we present results from a series of experiments using a 2-D coupled energy balance-ice flow model that investigate the palaeoclimate significance of Last Glacial Maximum moraines within nine catchments in the central North Island, New Zealand. We find that the former ice limits can be simulated when present-day temperatures are reduced by between 4 and 7 °C, if precipitation remains unchanged from present. The spread in the results between the nine catchments is likely to represent the combination of chronological and model uncertainties. The majority of catchments targeted require temperature decreases of 5.1 to 6.3 °C to simulate the former glaciers, which represents our best estimate of the temperature anomaly in the central North Island, New Zealand, during the Last Glacial Maximum. A decrease in precipitation of up to 25 % from present, as suggested by proxy evidence and climate models, increases the magnitude of the required temperature changes by up to 0.8 °C. Glacier model experiments using reconstructed topographies that exclude the volume of post-glacial ( < 15 ka) volcanism generally increased the magnitude of cooling required to simulate the former ice limits by up to 0.5 °C. Our palaeotemperature estimates expand the spatial coverage of proxy-based quantitative palaeoclimate reconstructions in New Zealand. Our results are also consistent with independent, proximal temperature reconstructions from fossil groundwater and pollen assemblages, as well as similar glacier modelling reconstructions from the central Southern Alps, which suggest air temperatures were ca. 6 °C lower than present across New Zealand during the Last

  14. New insights into the earliest Quaternary environments in the Central North Sea from 3D seismic

    NASA Astrophysics Data System (ADS)

    Lamb, Rachel; Huuse, Mads; Stewart, Margaret; Brocklehurst, Simon H.

    2014-05-01

    In the past the transition between an unconformable surface in the south to a conformable horizon towards the north has made identification and mapping the base-Quaternary in the central North Sea difficult (Sejrup et al 1991; Gatliff et al 1994). However recent integration of biostratigraphy, pollen analysis, paleomagnetism and amino acid analysis in the Dutch and Danish sectors (Rasmussen et al 2005; Kuhlmann et al 2006) has allowed greater confidence in the correlation to the region 3D seismic datasets and thus has allowed the base-Quaternary to be mapped across the entire basin. The base-Quaternary has been mapped using the PGS MegaSurvey dataset from wells in the Danish Sector along the initially unconformable horizon and down the delta front into the more conformable basin giving a high degree of confidence in the horizon pick. The revised base-Quaternary surface reaches a depth of 1248 ms TWT with an elongate basin shape which is significantly deeper than the traditionally mapped surface. Using RMS amplitudes and other seismic attributes the revised base-Quaternary has been investigated along the horizon and in time slice to interpret the environments of the earliest Quaternary prior to the onset of glaciation. Combined with analysis of aligned elongate furrows over 10 km long, 100 m wide and 100 m deep suggest a deep marine environment in an almost enclosed basin with persistent strong NW-SE bottom currents in the deepest parts. Pockmarks were formed by the escape of shallow gas on the sides of a small delta in the eastern part of the basin. The progradation of large deltas from both the north and south into the basin make up the majority of the deposition of sediment into the basin. Key Words: base-Quaternary; seismic interpretation; paleoenvironments References: Gatliff, R.W, Richards, P.C, Smith, K, Graham, C.C, McCormac, M, Smith, N.J.P, Long, D, Cameron, T.D.J, Evans, D, Stevenson, A.G, Bulat, J, Ritchie, J.D, (1994) 'United Kingdom offshore regional

  15. Modal Composition and Age of Intrusions in North-Central and Northeast Nevada

    USGS Publications Warehouse

    du Bray, Edward A.; Crafford, A. Elizabeth Jones

    2007-01-01

    Introduction Data presented in this report characterize igneous intrusions of north-central and northeast Nevada and were compiled as part of the Metallogeny of the Great Basin project conducted by the U.S. Geological Survey (USGS) between 2001 and 2007. The compilation pertains to the area bounded by lats 38.5 and 42 N., long 118.5 W., and the Nevada-Utah border (fig. 1). The area contains numerous large plutons and smaller stocks but also contains equally numerous smaller, shallowly emplaced intrusions, including dikes, sills, and endogenous dome complexes. Igneous intrusions (hereafter, intrusions) of multiple ages are major constituents of the geologic framework of north-central and northeast Nevada (Stewart and Carlson, 1978). Mesozoic and Cenozoic intrusions are particularly numerous and considered to be related to subduction along the west edge of the North American plate during this time. Henry and Ressel (2000) and Ressel and others (2000) have highlighted the association between magmatism and ore deposits along the Carlin trend. Similarly, Theodore (2000) has demonstrated the association between intrusions and ore deposits in the Battle Mountain area. Decades of geologic investigations in north-central and northeast Nevada (hereafter, the study area) demonstrate that most hydrothermal ore deposits are spatially, and probably temporally and genetically, associated with intrusions. Because of these associations, studies of many individual intrusions have been conducted, including those by a large number of Master's and Doctoral thesis students (particularly University of Nevada at Reno students and associated faculty), economic geologists working on behalf of exploration and mining companies, and USGS earth scientists. Although the volume of study area intrusions is large and many are associated with ore deposits, no synthesis of available data that characterize these rocks has been assembled. Compilations that have been produced for intrusions in Nevada

  16. Bioavailability of Metals in Sediments of the Dogger Bank (Central North Sea): A Mesocosm Study

    NASA Astrophysics Data System (ADS)

    Langston, W. J.; Burt, G. R.; Pope, N. D.

    1999-05-01

    There are conflicting arguments surrounding the nature and origins of metal enrichment in sediments from the Dogger Bank (central North Sea) and much speculation as to its biological significance. To help resolve this controversy, a mesocosm approach was evaluated to test whether metal loadings in sediments from the Dogger Bank region display enhanced bioavailability, relative to reference sites off south-west England. This involved the combination of physicochemical characterization of sediments (including porewaters) with bioaccumulation studies, using sediment cores seeded with benthic organisms (bivalves Spisula solida and Venus striatula, the gastropod Turritella communis and the polychaete Melinna palmata). There was little evidence of As, Cu, Hg or Pb bioaccumulation from Dogger cores. In contrast, all species accumulated Cd; Ag concentrations rose by up to fourfold in most bioindicators; and Ni, Cr and Mn burdens also increased, occasionally by as much as 10-fold. Variable, but generally smaller increases in Fe and Zn were observed. Physiological variations in metal bioaccumulation processes, including the ability to regulate essential elements, were responsible for species differences in response—a feature which may contribute to uncertainty in the interpretation and comparison of biomonitoring data. Mesocosm results nevertheless complement earlier field reports of unexpectedly enriched levels of certain metals (notably Cd) in biota from this part of the central North Sea. Characterization of sediments provided some physicochemical explanations for enhanced metal uptake in biota and helped, partly, to define bioavailable and anthropogenic fractions. Thus, whilst total sediment-metal concentrations were not exceptional in Dogger samples, for some metals there was a significant proportion in non-refractory (readily extractable) form, together with relatively high concentrations in interstitial waters—both presumably available for assimilation

  17. A Quantitative Analysis of Rift Processes in the Northern North Sea and Central Greece.

    NASA Astrophysics Data System (ADS)

    Bryon, J. G.; White, N. J.

    2003-12-01

    Actively extending sedimentary basins provide a snapshot of the way in which basins evolve. Our observations from such regions are temporally limited: we have little understanding of the long-term processes involved but an excellent understanding of the short-term motions (100-102 years). The converse is true of tectonically dead basins where the deformation has ceased and only the end product can be observed. Studies of active basin formation in central Greece have provided a quantitative understanding of the kinematics of extensional tectonics. The use of GPS, SAR interferometry and geomorphological analysis has constrained the rate of extension and fault kinematics and geometries. Central Greece has often been cited as a present-day analogue for formation of the now inactive East Shetland Basin (ESB) in the northern North Sea. A large 3D seismic dataset has been compiled giving complete coverage of the ESB, a region comparable in size to central Greece ( ˜10,000 km2). A quantitative comparison between Greece and the ESB will close the gap in knowledge between short-term and long-term motions. Whilst the two regions have many features in common, such as tilted fault blocks, fault segments of comparable length and similar fault geometries, there are also important differences. For example, one difference between Greece and the northern North Sea is the rate of extension. The North Sea had a peak strain rate that was an order of magnitude slower than the rate at which Greece is currently extending across the gulfs of Corinth and Evia. Another difference is that the distance between large active faults in Greece appears to be significantly longer than in the ESB. A specific example of this difference in scale is the Tern-Eider ridge, which is a horst block in the ESB that appears superficially similar to the island of Evia in Greece. However, the rigid island of Evia is significantly wider than the Tern-Eider ridge. A link between this inter-fault distance and

  18. Regional trends in mercury distribution across the Great Lakes states, north central USA

    NASA Astrophysics Data System (ADS)

    Nater, Edward A.; Grigal, David F.

    1992-07-01

    CONCENTRATIONS of mercury in the environment are increasing as a result of human activities, notably fossil-fuel burning and incineration of municipal wastes. Increasing levels of mercury in aquatic environments and consequently in fish populations are recognized as a public-health problem1,2. Enhanced mercury concentrations in lake sediments relative to pre-industrial values have also been attributed to anthropogenic pollution. It is generally assumed that atmospheric mercury deposition is dominated by global-scale processes, consequently being regionally uniform. Here, to the contrary, we report a significant gradient in concentrations and total amounts of mercury in organic litter and surface mineral soil along a transect of forested sites across the north central United States from northwestern Minnesota to eastern Michigan. This gradient is accompanied by parallel changes in wet sulphate deposition and human activity along the transect, suggesting that the regional variation in mercury content is due to deposition of anthropogenic mercury, most probably in particulate form.

  19. Sirte Basin, north-central Libya: Cretaceous rifting above a fixed mantle hotspot?

    NASA Astrophysics Data System (ADS)

    van Houten, Franklyn B.

    1983-02-01

    The complex pattern of horsts and grabens in the Sirte Basin may have developed when Mesozoic drift of the African plate put north-central Libya over a fixed mantle hotspot in Early Cretaceous time (140 to 100 m.y. ago). Significant change in the motion of the plate during the prolonged residence above a hypothetical Cameroon plume may have produced stress that fragmented thinned and weakened lithosphere. Successive uplift and subsidence along a reconstructed track of the plume, as well as in the Sirte Basin, are compatible with predicted effects of the drift of northern Africa over a fixed mantle hotspot. This speculation suggests a plausible alternative to the possibility that rifting throughout northern Africa in Early Cretaceous time may have been produced along a wide zone of extension between two African plates when they were at rest relative to underlying plumes.

  20. Hydrology of Prairie Dog Creek Valley, Norton Dam to state line, north-central Kansas

    USGS Publications Warehouse

    Stullken, L.E.

    1984-01-01

    Development of water resources has been a major factor in the economy of Prairie Dog Creek Valley in north-central Kansas. Releases from Norton Reservoir to the Almena Irrigation District averaged 6,900 acre-feet per year during 1967-76. The number of irrigation wells increased from 4 to 147 during 1947-78. Ground water in the valley is derived mostly from the alluvial aquifer. The effects of irrigation on the aquifer are indicated by water-level changes. The water in storage increased from 130,000 to 136,000 acre-feet during 1947-78 due to recharge from surface-water irrigation. A steady-state model of the aquifer prior to irrigation (1947) indicated that most recharge was from precipitation (88 percent) and most discharge was to streams (54 percent) and reparian transpiration (26 percent). Although aquifer storage increased in this area, storage generally decreased in other areas of western Kansas. (USGS)

  1. The in vitro isolation of Blastomyces dermatitidis from a woodpile in north central Wisconsin, USA.

    PubMed

    Baumgardner, D J; Paretsky, D P

    1999-06-01

    Environmental isolations of the dimorphic fungus, Blastomyces dermatitidis, the aetiologic agent of blastomycosis are rare, and have usually involved animal inoculation techniques. We report the in vitro isolation of B. dermatitidis from a woodpile in November 1997, from a private property in a highly endemic area of north central Wisconsin, USA. The woodpile was 73 m from the Wisconsin River and 5 m from a kennel which had housed nine dogs over the past 14 years, four of which had been diagnosed with blastomycosis. One of 19 samples from the property yielded B. dermatitidis after 37 degrees C incubation in a neutral aqueous solution of allantoin, Tween-80, potassium phosphate, magnesium sulphate, penicillin and streptomycin followed by plating on yeast-extract phosphate agar at 20 degrees C. Refinements of this technique may help further elucidate the ecological niche of B. dermatitidis. PMID:10421847

  2. Potentiometric surface of the Peedee Aquifer in the central coastal plain of North Carolina, December 1986

    USGS Publications Warehouse

    Brockman, Allen R.; Lyke, William L.; Winner, M.D., Jr.

    1989-01-01

    Water level measurements were made in 37 wells open to the Peedee aquifer at the end of 1986 to determine the configuration of its potentiometric surface over an area of about 4,100 square miles in the central Coastal Plain of North Carolina. The potentiometric surface of the Peedee slopes southeastward from an altitude of more than 100 ft above sea level along the western limits of the aquifer to less than 20 ft near the coastline. Several cones of depression have formed in response to the effects of groundwater pumpage. The largest cone occurs near the City of Jacksonville in Onslow County where the potentiometric surface is nearly 70 ft below sea level.

  3. Characteristics of central North Dakota wetlands determined from sample aerial photographs and ground study

    USGS Publications Warehouse

    Cowardin, L.M.; Gilmer, D.S.; Mechlin, L.M.

    1981-01-01

    Wetland characteristics were assessed from a systematic sample of 66 plots, 3.22 km2 each, drawn from a 10,041-km2 study area in central North Dakota. Each plot was visited once and 8 sets of aerial photographs were obtained in 3 years. Density of wetland basins was 11.00 ha/km2, and area averaged 9.7 ha/km2. Seasonal and temporary wetlands were most abundant; semipermanent wetlands occupied the greatest area. Basin size was positively correlated with water permanence. Discriminant function analysis based on size and an index to wetness derived from photographs misclassified 33% of the wetland basins. Forty percent of the wetlands were tilled. Photography of sample plots is potentially useful for determining number of basins and wetland area, but precise classification of plant communities in this region would require ground study.

  4. The development of the East African Rift system in north-central Kenya

    NASA Astrophysics Data System (ADS)

    Hackman, B. D.; Charsley, T. J.; Key, R. M.; Wilkinson, A. F.

    1990-11-01

    Between 1980 and 1986 geological surveying to produce maps on a scale of 1:250,000 was completed over an area of over 100,000 km 2 in north-central Kenya, bounded by the Equator, the Ethiopian border and longitudes 36° and 38 °E. The Gregory Rift, much of which has the structure of an asymmetric half-graben, is the most prominent component of the Cenozoic multiple rift system which extends up to 200 km to the east and for about 100 km to the west, forming the Kenya dome. On the eastern shoulder and fringes two en echelon arrays of late Tertiary to Quaternary multicentre shields can be recognized: to the south is the Aberdares-Mount Kenya-Nyambeni Range chain and, to the north the clusters of Mount Kulal, Asie, Huri Hills and Marsabit, with plateau lavas and fissure vents south of Marsabit in the Laisamis area. The Gregory Rift terminates at the southern end of Lake Turkana. Further north the rift system splays: the arcuate Kinu Sogo fault zone forms an offset link with the central Ethiopian Rift system. In the rifts of north-central Kenya volcanism, sedimentation and extensional tectonics commenced and have been continuous since the late Oligocene. Throughout this period the Elgeyo Fault acted as a major bounding fault. A comparative study of the northern and eastern fringes of the Kenya dome with the axial graben reinforces the impression of regional E-W asymmetry. Deviations from the essential N-trend of the Gregory Rift reflect structural weaknesses in the underlying Proterozoic basement, the Mozambique Orogenic Belt: thus south of Lake Baringo the swing to the southeast parallels the axes of the ca. 620 Ma phase folds. Secondary faults associated with this flexure have created a "shark tooth" array, an expression of en echelon offsets of the eastern margin of the Gregory Rift in a transtensional stress regime: hinge zones where major faults intersect on the eastern shoulder feature intense box faulting and ramp structures which have counterparts in the rift

  5. Geochemical Database for Intrusive Rocks of North-Central and Northeast Nevada

    USGS Publications Warehouse

    du Bray, Edward A.; Ressel, Michael W.; Barnes, Calvin G.

    2007-01-01

    North-central and northeast Nevada contains numerous large plutons and smaller stocks but also contains many small, shallowly emplaced intrusive bodies, including dikes, sills, and intrusive lava dome complexes. Decades of geologic investigations in the study area demonstrate that many ore deposits, representing diverse ore deposit types, are spatially, and probably temporally and genetically, associated with these igneous intrusions. However, despite the number and importance of igneous intrusions in the study area, no synthesis of geochemical data available for these rocks has been completed. This report presents a synthesis of geochemical data for these rocks. The product represents the first phases of an effort to evaluate the time-space-compositional evolution of Mesozoic and Cenozoic magmatism in the study area and identify genetic associations between magmatism and mineralizing processes in this region.

  6. Computer and photogrammetric general land use study of central north Alabama

    NASA Technical Reports Server (NTRS)

    Jayroe, R. R.; Larsen, P. A.; Campbell, C. W.

    1974-01-01

    The object of this report is to acquaint potential users with two computer programs, developed at NASA, Marshall Space Flight Center. They were used in producing a land use survey and maps of central north Alabama from Earth Resources Technology Satellite (ERTS) digital data. The report describes in detail the thought processes and analysis procedures used from the initiation of the land use study to its completion, as well as a photogrammetric study that was used in conjunction with the computer analysis to produce similar land use maps. The results of the land use demonstration indicate that, with respect to computer time and cost, such a study may be economically and realistically feasible on a statewide basis.

  7. Late Cenozoic crustal deformation of the north-central Basin and Range

    SciTech Connect

    Eyal, Y. . Dept. of Geology); Ron, H. )

    1993-04-01

    Late Cenozoic deformation of Basin and Range in north-central Nevada is examined by small fault analysis. Consistency between fault types, fault trends and sense of displacement was found for this area in which normal faults strike N-S, and right-lateral and left-lateral faults strike NNW and NNE respectively. The existence of strike-slip faulting, mainly right-lateral, is consistent with horizontal counter clockwise rotation suggested by paleomagnetic declination data. The results of this analysis indicate that crustal deformation of this area did not occur by only simple E-W uniaxial extension but also by N-S compression and shortening, and that the contribution of strike slip faulting to the extension of this area is substantial almost similar to that of normal faulting.

  8. Remote sensing data of SP mountain and SP lava flow in north-central Arizona

    NASA Technical Reports Server (NTRS)

    Schaber, G. G.; Elachi, C.; Farr, T. G.

    1980-01-01

    Multifrequency airborne radar image data of SP Mountain and SP flow in north-central Arizona were obtained in diverse viewing directions and direct and cross-polarization and compared with surface and aerial photography, Landsat multispectral scanner data, airborne thermal infrared imagery, surface geology, and surface roughness statistics. The extremely blocky, basaltic andesite of SP flow is brighter on direct-polarization K-band images than on cross-polarized images taken simultaneously. This effect is explained by multiple scattering and the strong wavelength dependence of polarization effects caused by the rectilinear basaltic andesite scatters. Two distinct types of surface relief on SP flow, one extremely blocky, the other subdued, are clearly discriminated on the visible and thermal wavelength images but are separable only on the longer wavelength L-band radar image data.

  9. (137)Cs vertical distribution at the deep basins of the North and Central Aegean Sea, Greece.

    PubMed

    Tsabaris, C; Zervakis, V; Kaberi, H; Delfanti, R; Georgopoulos, D; Lampropoulou, M; Kalfas, C A

    2014-06-01

    Large volume seawater samples were collected for the determination of (137)Cs concentration along with depth in the deep basins of North and Central Aegean Sea. The vertical (137)Cs distribution showed maximum concentration at the bottom of the basins, while the minimum values corresponded to the intermediate layer, where Levantine water exists. The surface (137)Cs activity is found to lie between the two limits and is originated from the Black Sea waters. The typical oceanographic advection-diffusion balance model is modified to a diffusion-settling-decay balance model to better understand the vertical distribution and variation of the (137)Cs concentration in the deep basins. In addition, the diffusivity of each basin, as well as the settling speed of particulate (137)Cs is also estimated. The results are compared with theoretical approach as well as with previous data. PMID:24534571

  10. New Vitrinite Reflectance Data for the Bighorn Basin, North-Central Wyoming and South-Central Montana

    USGS Publications Warehouse

    Finn, Thomas M.; Pawlewicz, Mark J.

    2007-01-01

    Introduction The Bighorn Basin is a large Laramide (Late Cretaceous through Eocene) structural and sedimentary basin that encompasses about 10,400 mi2 in north-central Wyoming and south-central Montana (fig. 1). Important conventional oil and gas resources have been discovered and produced from reservoirs ranging in age from Cambrian through Tertiary (Fox and Dolton, 1989, 1996a, b; De Bruin, 1993). In addition, a potential unconventional basin-centered gas accumulation may be present in Cretaceous reservoirs (Johnson and Finn, 1998; Johnson and others, 1999). The purpose of this report is to present new vitrinite reflectance data to be used in support of the U.S Geological Survey's assessment of undiscovered oil and gas resources of the Bighorn Basin. These new data supplement previously published data by Nuccio and Finn (1998), and Yin (1997), and lead to a better understanding and characterization of the thermal maturation and burial history of potential source rocks. Eighty-nine samples of Cretaceous and Tertiary strata (fig. 2) were collected and analyzed - 15 samples were from outcrops around the margins of the basin and 74 samples were well cuttings (fig. 1). Forty-one of the samples were shale, two were carbonaceous shale, and the remainder from coal. All samples were analyzed by vitrinite reflectance to determine levels of thermal maturation. Preparation of samples for reflectance analysis required (1) crushing the larger pieces into 0.25-to 1-mm pieces, (2) casting the pieces with epoxy in pre-cut and drilled plugs, and (3) curing the samples overnight. Subsequently, a four-step grinding and polishing process was implemented that included sanding with progressively finer sandpaper (60 and 600 grit) followed with a two-step polishing process (0.3 and 0.05 micron). Vitrinite reflectance measurements were determined at 500 X magnification using plane-polarized incident white light and a 546-nm monochromatic filter in immersion oil. For samples containing

  11. Land cover mapping of North and Central America—Global Land Cover 2000

    USGS Publications Warehouse

    Latifovic, Rasim; Zhu, Zhi-Liang

    2004-01-01

    The Land Cover Map of North and Central America for the year 2000 (GLC 2000-NCA), prepared by NRCan/CCRS and USGS/EROS Data Centre (EDC) as a regional component of the Global Land Cover 2000 project, is the subject of this paper. A new mapping approach for transforming satellite observations acquired by the SPOT4/VGTETATION (VGT) sensor into land cover information is outlined. The procedure includes: (1) conversion of daily data into 10-day composite; (2) post-seasonal correction and refinement of apparent surface reflectance in 10-day composite images; and (3) extraction of land cover information from the composite images. The pre-processing and mosaicking techniques developed and used in this study proved to be very effective in removing cloud contamination, BRDF effects, and noise in Short Wave Infra-Red (SWIR). The GLC 2000-NCA land cover map is provided as a regional product with 28 land cover classes based on modified Federal Geographic Data Committee/Vegetation Classification Standard (FGDC NVCS) classification system, and as part of a global product with 22 land cover classes based on Land Cover Classification System (LCCS) of the Food and Agriculture Organisation. The map was compared on both areal and per-pixel bases over North and Central America to the International Geosphere–Biosphere Programme (IGBP) global land cover classification, the University of Maryland global land cover classification (UMd) and the Moderate Resolution Imaging Spectroradiometer (MODIS) Global land cover classification produced by Boston University (BU). There was good agreement (79%) on the spatial distribution and areal extent of forest between GLC 2000-NCA and the other maps, however, GLC 2000-NCA provides additional information on the spatial distribution of forest types. The GLC 2000-NCA map was produced at the continental level incorporating specific needs of the region.

  12. Geology and petroleum resources of north-central and northeast Africa

    SciTech Connect

    Peterson, J.A.

    1986-05-01

    In north-central and northeast Africa, important petroleum accumulations exist in the Sirte basin of Libya, the western Sahara region of Algeria, the Pelagian platform offshore from eastern Tunisia, and in the Western Desert basin, Suez graben, and Nile delta in Egypt. Approximately 55 major fields (> 100 million BOE), of which 15 are giants (> 1 billion BOE), have been found in these provinces. Total estimated ultimate production from existing fields in 60 billion bbl of oil and 100 tcf of gas; estimated undiscovered petroleum resources are 26 billion bbl of oil and 93 tcf of gas. The post-Precambrian sedimentary basins of north Africa are related to the development of the Sahara platform during at least four main tectonic episodes (the Caledonian, Hercynian, Laramide, and Alpine cycles). The sedimentary cover of the platform, which includes rocks of all geologic systems, ranges from less than 1000 m (3300 ft) in the south to more than 9000 m (30,000 ft) along the Mediterranean coast. Paleozoic rocks are primarily continental and nearshore marine sandstone and shale, which are important reservoir and source rocks for petroleum in the central and western parts of the Sahara platform. Lower Mesozoic rocks were deposited in a continental and restricted marine environment, and contain thick beds of red beds and evaporites, including salt, which are important seals for oil and gas fields. Upper Mesozoic and Tertiary rocks are related to the development of the Mediterranean Tethys geosyncline and are characterized by numerous transgressive-regressive cycles of the Tethyan seaway. Marine carbonate and shale facies are dominant in the Upper Jurassic, Cretaceous, and lower Tertiary section of northern Libya, eastern Tunisia-Pelagian platform, and northern Egypt. Upper Tertiary beds are continental clastics on most of the platform, except near the Mediterranean.

  13. Genetic Variation of Sclerotinia sclerotiorum from Multiple Crops in the North Central United States.

    PubMed

    Aldrich-Wolfe, Laura; Travers, Steven; Nelson, Berlin D

    2015-01-01

    Sclerotinia sclerotiorum is an important pathogen of numerous crops in the North Central region of the United States. The objective of this study was to examine the genetic diversity of 145 isolates of the pathogen from multiple hosts in the region. Mycelial compatibility groups (MCG) and microsatellite haplotypes were determined and analyzed for standard estimates of population genetic diversity and the importance of host and distance for genetic variation was examined. MCG tests indicated there were 49 different MCGs in the population and 52 unique microsatellite haplotypes were identified. There was an association between MCG and haplotype such that isolates belonging to the same MCG either shared identical haplotypes or differed at no more than 2 of the 12 polymorphic loci. For the majority of isolates, there was a one-to-one correspondence between MCG and haplotype. Eleven MCGs shared haplotypes. A single haplotype was found to be prevalent throughout the region. The majority of genetic variation in the isolate collection was found within rather than among host crops, suggesting little genetic divergence of S. sclerotiorum among hosts. There was only weak evidence of isolation by distance. Pairwise population comparisons among isolates from canola, dry bean, soybean and sunflower suggested that gene flow between host-populations is more common for some crops than others. Analysis of linkage disequilibrium in the isolates from the four major crops indicated primarily clonal reproduction, but also evidence of genetic recombination for isolates from canola and sunflower. Accordingly, genetic diversity was highest for populations from canola and sunflower. Distribution of microsatellite haplotypes across the study region strongly suggest that specific haplotypes of S. sclerotiorum are often found on multiple crops, movement of individual haplotypes among crops is common and host identity is not a barrier to gene flow for S. sclerotiorum in the north central United

  14. Climatic Forcing of Glacier Surface Mass Balance Changes Along North-Central Peru: A Modeling Perspective

    NASA Astrophysics Data System (ADS)

    Mark, B. G.; Fernandez, A.

    2015-12-01

    Most tropical glaciers are Peru, where they are key water sources for communities in mountain environments and beyond. Thus, their sustained shrinkage portrays these glaciers as archetype of global warming impacts on the local scale. However, there is still no deep understanding on the mechanism connecting temperature and these glaciers. Among others, the effect of temperature on the glacier surface mass balance (GSMB) can be expressed within accumulation regimes and hence in surface albedo, or in ablation dynamics through incoming longwave energy (LE). Here, we report a study combining statistical analyses of reanalysis data (~30km grid-cell), regional climate modeling and glacier mass balance simulations at high resolution (2km) to analyze long-term (30 years) and seasonal GSMB along north-central Peru. Our goal is to mechanistically understand climate change impact on these glaciers. Results suggest temperature as the main factor controlling GSMB changes through the lapse rate (LR). Correlations of GSMB with LR, humidity and zonal wind point to vertical homogenization of temperature, causing LE to increase, despite this flux always remaining negative. This "less negative" LE multiplies the impact of the seasonal fluctuation in albedo, thereby enhancing total ablation. As this mechanism only needs a relative increase in temperature, it may even occur in subfreezing conditions. Model output also indicates that turbulent fluxes are small, largely cancelling out. This suggests that the impact of LE is more likely to occur compared to either turbulent fluxes changes or shifts in the proportion of sublimation versus melt, which we find to be regionally stable. These findings imply that glaciers in north-central Peru are sensitive to subtle changes in temperature. We discuss the implications for process-based understanding and how this non-linear and somewhat hidden effect of temperature reduces the skill of temperature index models to simulate GSMB in the Tropics.

  15. Mediterranean climate patterns and wine quality in North and Central Italy

    NASA Astrophysics Data System (ADS)

    Dalu, John David; Baldi, Marina; Dalla Marta, Anna; Orlandini, Simone; Maracchi, Gianpiero; Dalu, Giovanni; Grifoni, Daniele; Mancini, Marco

    2013-09-01

    Results show that the year-to-year quality variation of wines produced in North and Central Italy depends on the large-scale climate variability, and that the wine quality improvement in the last four decades is partially due to an increase of temperature and to a decrease of precipitation in West and Central Mediterranean Europe (WME; CME). In addition, wine quality is positively correlated with air temperature throughout the entire active period of the grapevine, weakly negatively correlated with precipitation in spring, and well negatively correlated in summer and fall. The month-to-month composites of the NAO anomaly show that, in years of good quality wine, this anomaly is negative in late spring, oscillates around zero in summer, and is positive in early fall; while, in years of bad quality wine, it is positive in late spring and summer, and negative in early fall, i.e. its polarity has an opposite sign in spring and fall in good versus bad years. The composite seasonal maps show that good wines are produced when the spring jet stream over the Atlantic diverts most of the weather perturbations towards North Europe, still providing a sufficient amount of rainwater to CME; when summer warming induced by southerly winds is balanced by the cooling induced by westerly winds; and when a positive geopotential anomaly over WME shelters CME from fall Atlantic storms. Bad quality wines are produced when the jet stream favors the intrusion of the Atlantic weather perturbations into the Mediterranean. Results suggest that atmospheric pattern persistencies can be used as precursors for wine quality forecast.

  16. Genetic Variation of Sclerotinia sclerotiorum from Multiple Crops in the North Central United States

    PubMed Central

    Aldrich-Wolfe, Laura; Travers, Steven; Nelson, Berlin D.

    2015-01-01

    Sclerotinia sclerotiorum is an important pathogen of numerous crops in the North Central region of the United States. The objective of this study was to examine the genetic diversity of 145 isolates of the pathogen from multiple hosts in the region. Mycelial compatibility groups (MCG) and microsatellite haplotypes were determined and analyzed for standard estimates of population genetic diversity and the importance of host and distance for genetic variation was examined. MCG tests indicated there were 49 different MCGs in the population and 52 unique microsatellite haplotypes were identified. There was an association between MCG and haplotype such that isolates belonging to the same MCG either shared identical haplotypes or differed at no more than 2 of the 12 polymorphic loci. For the majority of isolates, there was a one-to-one correspondence between MCG and haplotype. Eleven MCGs shared haplotypes. A single haplotype was found to be prevalent throughout the region. The majority of genetic variation in the isolate collection was found within rather than among host crops, suggesting little genetic divergence of S. sclerotiorum among hosts. There was only weak evidence of isolation by distance. Pairwise population comparisons among isolates from canola, dry bean, soybean and sunflower suggested that gene flow between host-populations is more common for some crops than others. Analysis of linkage disequilibrium in the isolates from the four major crops indicated primarily clonal reproduction, but also evidence of genetic recombination for isolates from canola and sunflower. Accordingly, genetic diversity was highest for populations from canola and sunflower. Distribution of microsatellite haplotypes across the study region strongly suggest that specific haplotypes of S. sclerotiorum are often found on multiple crops, movement of individual haplotypes among crops is common and host identity is not a barrier to gene flow for S. sclerotiorum in the north central United

  17. Mediterranean climate patterns and wine quality in North and Central Italy.

    PubMed

    Dalu, John David; Baldi, Marina; Marta, Anna Dalla; Orlandini, Simone; Maracchi, Gianpiero; Dalu, Giovanni; Grifoni, Daniele; Mancini, Marco

    2013-09-01

    Results show that the year-to-year quality variation of wines produced in North and Central Italy depends on the large-scale climate variability, and that the wine quality improvement in the last four decades is partially due to an increase of temperature and to a decrease of precipitation in West and Central Mediterranean Europe (WME; CME). In addition, wine quality is positively correlated with air temperature throughout the entire active period of the grapevine, weakly negatively correlated with precipitation in spring, and well negatively correlated in summer and fall. The month-to-month composites of the NAO anomaly show that, in years of good quality wine, this anomaly is negative in late spring, oscillates around zero in summer, and is positive in early fall; while, in years of bad quality wine, it is positive in late spring and summer, and negative in early fall, i.e. its polarity has an opposite sign in spring and fall in good versus bad years. The composite seasonal maps show that good wines are produced when the spring jet stream over the Atlantic diverts most of the weather perturbations towards North Europe, still providing a sufficient amount of rainwater to CME; when summer warming induced by southerly winds is balanced by the cooling induced by westerly winds; and when a positive geopotential anomaly over WME shelters CME from fall Atlantic storms. Bad quality wines are produced when the jet stream favors the intrusion of the Atlantic weather perturbations into the Mediterranean. Results suggest that atmospheric pattern persistencies can be used as precursors for wine quality forecast. PMID:23152193

  18. Geologic controls on the formation of lakes in north-central Florida

    USGS Publications Warehouse

    Kindinger, Jack G.; Davis, Jeffrey B.; Flocks, James G.

    1998-01-01

    Fluid exchange between surficial waters and groundwater, as well as the processes that control this exchange, are of critical concern to water management districts and planners. Digital high-resolution seismic systems were used to collect geophysical data from 30 lakes of north-central Florida. Although using seismic profile data in the past has been less than successful, the use of digital technology has increased the potential for success. Seismic profiles collected from the lakes of north-central Florida have shown the potential application of these techniques in understanding the formation of individual lakes. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: 1) karstification or dissolution of the underlying limestone, and 2) me collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Lake size and shape are a factor of the thickness of overburden and size of the collapse or subsidence and/or clustering of depressions allowing for lake development. Lake development is through progressive sequence stages to maturity that can be delineated into geomorphic types. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phases: (1) active subsidence or collapse phase (young) - the open to partially filled collapse structures typically associated with sink holes; (2) transitional phase (middle age) - the sinkhole is plugged as the voids within the collapse are filled with sediment, periodic reactivation may occur; (3) baselevel phase (mature) - active sinkholes are progressively plugged by the continual erosion of material into the basin, and eventually sediment fills the basins; and (4) polje (drowned prairie) - broad flat-bottom basins located within the epiphreatic zone that are inundated at high

  19. Characterization of smallholder pig breeding practices within a rural commune of North Central Vietnam.

    PubMed

    Ieda, Nahoko; Van Bui, Quang; Nguyen, Nga Thi Duong; Lapar, Lucy; Marshall, Karen

    2015-08-01

    This case study focused on a pig production system in a rural area of North Central Vietnam, with a focus on describing household pig breeding practices and estimating herd demographic parameters, particularly on reproduction. One hundred five households undertaking small-scale piglet production were surveyed, with information gathered on 3268 individual pigs. Pig keeping contributed variably to the overall household livelihood portfolio, with female household members as the main decision makers, contributors to labor, and beneficiaries of income from the pig enterprise. All households kept between one and four young or adult sows, with 69% of these sows of a local breed type (predominantly Mong Cai), 28% a cross between a local sow and an exotic sow (predominantly Large White), and the remainder (3%) as exotic sows. Eighty-eight percent of the piglets produced were cross-bred, while 12% were local breed. No adult males were kept by the surveyed households, reflecting the common use of artificial insemination for mating purposes. The most common breeding system practiced-the keeping of Mong Cai females and production of cross-bred piglets-capitalizes on the small body size and high fecundity of the sows and the fast growth rate and leanness of the cross-bred piglets. The survey tool used, which was based on farmer recall of events over the preceding 12-month period, appeared to give reasonable results although some recall bias could be detected. This case study will serve as an entry point to planned broader scale characterization and development of pig breeding systems in North Central Vietnam. PMID:25947237

  20. Characterization and geochemistry of Devonian oil shale North Alabama - South Central Tennessee

    USGS Publications Warehouse

    Rheams, K.F.; Neathery, T.L.

    1984-01-01

    Based on the physical and chemical data obtained to date, the Devonian oil shale rock of north Alabama and south-central Tennessee appears to offer an attractive potential for future resource development. The shale rock appears to have formed in a restrictive marine environment which provided opportunity for the accumulation of marine organic matter to form sufficient kerogen. The shale contains approximately 18% to 22% organic matter which is primarily kerogen. The kerogen has a relatively high H:C ratio indicative of an alginite and/or exinite source (Type 1 and Type II kerogen) and a high proportion of alkane and saturated ring hydrocarbons. However, a few samples have low H:C ratio values and are interpreted to have been formed in a shallow water oxidizing environment. Also, there is a possibility that these low H:C values may represent mixtures of terrestrial and marine organic material suggesting lateral facies changes of the rock from marine to near shore depositional environments. Trace metal values for both the whole rock and the shale oil fraction indicate a generally high V:Ni ratio, also indicative of a marine environment. Other trace metal values are in good agreement with data from other Devonian shales. Throughout the north Alabama and south-central Tennessee study area, the average oil yield from the shale is 13.9 gallon per ton. The highest oil yield values were obtained from the middle and upper parts of the shale sequence. Based on the crude oil composition diagram (11), the Alabama-Tennessee shale oil is classified as a aromatic-intermediate oil Estimated reserves of inplace shale oil resources in the principal study area, under less than 200 feet of overburden, exceeds 12.5 billion barrels.

  1. Changing central Pacific El Niños reduce stability of North American salmon survival rates

    PubMed Central

    Kilduff, D. Patrick; Di Lorenzo, Emanuele; Botsford, Louis W.; Teo, Steven L. H.

    2015-01-01

    Pacific salmon are a dominant component of the northeast Pacific ecosystem. Their status is of concern because salmon abundance is highly variable—including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the Pacific Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with central tropical Pacific warming (CPW) rather than the canonical eastern Pacific warming ENSO (EPW). CPW is linked to the North Pacific Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast Pacific Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions. PMID:26240365

  2. Geographical characterization of the triatomine infestations in north-central Guatemala.

    PubMed

    Nakagawa, J; Juárez, J; Nakatsuji, K; Akiyama, T; Hernandez, G; Macal, R; Flores, C; Ortiz, M; Marroquín, L; Bamba, T; Wakai, S

    2005-04-01

    In an entomological study in 2002, the degree of domestic and peridomestic infestation with triatomine bugs and the geographical distribution of such infestations were investigated in north-central Guatemala. The survey team searched for triatomines in houses constructed with mud walls or thatched roofs, in villages suspected of being infested. The level of infestation observed was lower than that seen in the same area and in eastern Guatemala, in a preliminary survey, 3 years earlier. Most of the infestations detected were of Triatoma dimidiata but even this species was found in <7% of the houses investigated. Infestations with Rhodnius prolixus or other potential vectors of Trypanosoma cruzi were much rarer. The generally low levels of infestation make the elimination of R. prolixus and the reduction of the domestic population of Tri. dimidiata feasible in the study area. The southern part of the study area had higher levels of domestic infestation and colonization than the north, and peridomestic infestation was highest in the south-west. Given such geographical variation in the pattern of infestation, it would seem wise to stratify the study region into areas of high, moderate and low-risk of human-triatomine contact, so that appropriate vector-control strategies can be targeted at the worst-affected areas. Regular entomological surveillance, ideally with community participation, is recommended. Analysis of the relationship between the geographical patterns of infestation and factors such as vegetation, altitude and vector migration would be useful. PMID:15829138

  3. Overview of the central North American basins and their relation to deep curstal structure

    SciTech Connect

    Keller, G.R.; Denison, R.E.

    1984-04-01

    As our knowledge of deep structure of major central North American basins has increased, it has become clear that they have experienced long and complicated tectonic histories. A knowledge of these histories is especially important to efforts to formulate exploration strategies for deeper horizons and frontier areas. Regional geophysical and geologic studies of these basins indicate that Precambrian features have often exerted considerable control on basinal development (e.g., Anadarko basin, Rome trough, Rough Creek graben, Pedregosa basin). A particularly important tectonic event was the Eocambrian continental breakup which extensively rifted the southern margin of North America. Although this rifting event is manifested in various ways, its extent can be estimated by mapping he deep-seated crustal anomalies which probably formed at this time. Although age relations are uncertain in most cases, deep-seated anomalies are associated with the Arkoma basin, Anadarko basin, Illinois basin, Mississippi embayment, and Permian basin. There are many similarities in the development of these basins, but they all can be shown to have unique tectonic histories.

  4. Greenhouse gas fluxes of a shallow lake in south-central North Dakota, USA

    USGS Publications Warehouse

    Tangen, Brian; Finocchiaro, Raymond; Gleason, Robert A.; Dahl, Charles F.

    2016-01-01

    Greenhouse gas (GHG) fluxes of aquatic ecosystems in the northern Great Plains of the U.S. represent a significant data gap. Consequently, a 3-year study was conducted in south-central North Dakota, USA, to provide an initial estimate of GHG fluxes from a large, shallow lake. Mean GHG fluxes were 0.02 g carbon dioxide (CO2) m−2 h−1, 0.0009 g methane (CH4) m−2 h−1, and 0.0005 mg nitrous oxide (N2O) m−2 h−1. Fluxes of CO2 and CH4 displayed temporal and spatial variability which is characteristic of aquatic ecosystems, while fluxes of N2O were consistently low throughout the study. Comparisons between results of this study and published values suggest that mean daily fluxes of CO2, CH4, and N2O fromLong Lakewere low, particularly when compared to the well-studied prairie pothole wetlands of the region. Similarly, cumulative seasonal CH4 fluxes, which ranged from 2.68–7.58 g CH4 m−2, were relatively low compared to other wetland systems of North America. The observed variability among aquatic ecosystems underscores the need for further research.

  5. Chemostratigraphy of Upper Cretaceous chalk sequences in Norwegian-Danish basin and North Sea Central Trough

    SciTech Connect

    Joergensen, N.O.

    1987-05-01

    Geochemical studies of subsurface sections and outcrops in the Upper Cretaceous chalk sequences from the Norwegian-Danish basin and the North Sea Central Trough have resulted in a detailed chemostratigraphy for these strata. The most applicable chemostratigraphic markers are based on the distribution of strontium, magnesium, manganese, the /sup 13/C//sup 12/C ratio, and the variations in the carbonate contents. It is demonstrated that the chemostratigraphic approach is valid at two levels: (1) a superior chemostratigraphy in which deep-sea cores from the Atlantic Ocean and sections from western Europe are correlated on the basis of significant geochemical anomalies and long-term variations most likely induced by oceanic geochemical cycles and sea level fluctuations; (2) a subordinate but detailed intrabasinal chemostratigraphic correlation which primarily reflects the physicochemical conditions in the depositional environment. The Upper Cretaceous chemostratigraphy established in the Danish area allows a detailed correlation between relatively continuous chalk sequences in the Norwegian-Danish basin and the rather condensed and hiati-influenced sections in the oil fields of the North Sea. The results emphasize the applicability of chemostratigraphy in the subsurface exploration for hydrocarbon reservoirs in chalk.

  6. Changing central Pacific El Niños reduce stability of North American salmon survival rates.

    PubMed

    Kilduff, D Patrick; Di Lorenzo, Emanuele; Botsford, Louis W; Teo, Steven L H

    2015-09-01

    Pacific salmon are a dominant component of the northeast Pacific ecosystem. Their status is of concern because salmon abundance is highly variable--including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the Pacific Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with central tropical Pacific warming (CPW) rather than the canonical eastern Pacific warming ENSO (EPW). CPW is linked to the North Pacific Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast Pacific Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions. PMID:26240365

  7. Probabilistic forecasts for Decision Support at the North Central River Forecast Center

    NASA Astrophysics Data System (ADS)

    Restrepo, Pedro; Buan, Steven; Connelly, Brian; DeWeese, Michael; Diamond, Laura; Ellis, Larry; Goering, Dustin; Holz, Andrea; Husaby, James; Merrigan, Douglas; Palmer, Justin; Pokorny, Daniel; Reckel, Holly; Sites, William; Stockhaus, Scott; Thornburg, Jonathon; Wavrin, Robert.; Ziemer, Mark

    2013-04-01

    The North Central River Forecast Center (NCRFC) of the US National Weather Service has the responsibility for issuing river forecasts at 426 points over an area of nearly 890,000 km2, covering the Upper Mississippi river basin, the US watersheds flowing to lakes Superior, Huron and Michigan, and rivers flowing from the US to the Hudson Bay in Canada. The NCRFC issues probabilistic outlook forecasts at all its forecast points starting on December. While focused primarily on the risks associated with flooding during the spring snow melt down, the RFC frequently issues probabilistic forecasts to deal with water resources operations during drought times. This presentation will focus on probabilistic forecasts issued to assess flooding risk at Red River of the North , to support navigation operations on the Mississippi river during drought conditions, and on support of reservoir operations for hydropower generation and recreation. The presentation will discuss the improvements over the current practice that will be possible to achieve once the NWS Hydrologic Ensemble Forecasting System is put into operations later this year.

  8. Naturalization of central European plants in North America: species traits, habitats, propagule pressure, residence time.

    PubMed

    Pyšek, Petr; Manceur, Ameur M; Alba, Christina; McGregor, Kirsty F; Pergl, Jan; Stajerová, Katerina; Chytrý, Milan; Danihelka, Jiří; Kartesz, John; Klimesova, Jitka; Lucanova, Magdalena; Moravcová, Lenka; Nishino, Misako; Sadlo, Jiri; Suda, Jan; Tichy, Lubomir; Kühn, Ingolf

    2015-03-01

    The factors that promote invasive behavior in introduced plant species occur across many scales of biological and ecological organization. Factors that act at relatively small scales, for example, the evolution of biological traits associated with invasiveness, scale up to shape species distributions among different climates and habitats, as well as other characteristics linked to invasion, such as attractiveness for cultivation (and by extension propagule pressure). To identify drivers of invasion it is therefore necessary to disentangle the contribution of multiple factors that are interdependent. To this end, we formulated a conceptual model describing the process of invasion of central European species into North America based on a sequence of "drivers." We then used confirmatory path analysis to test whether the conceptual model is supported by a statistical model inferred from a comprehensive database containing 466 species. The path analysis revealed that naturalization of central European plants in North America, in terms of the number of North American regions invaded, most strongly depends on residence time in the invaded range and the number of habitats occupied by species in their native range. In addition to the confirmatory path analysis, we identified the effects of various biological traits on several important drivers of the conceptualized invasion process. The data supported a model that included indirect effects of biological traits on invasion via their effect on the number of native range habitats occupied and cultivation in the native range. For example, persistent seed banks and longer flowering periods are positively correlated with number of native habitats, while a stress-tolerant life strategy is negatively correlated with native range cultivation. However, the importance of the biological traits is nearly an order of magnitude less than that of the larger scale drivers and highly dependent on the invasion stage (traits were associated

  9. Structural style of the Appalachian Plateau fold belt, north-central Pennsylvania

    NASA Astrophysics Data System (ADS)

    Mount, Van S.

    2014-12-01

    New seismic and well data from hydrocarbon exploration and development activity associated with the Marcellus Formation shale gas play in north-central Pennsylvania provide insight to the structural style of the Appalachian Plateau fold belt in the region north and northwest of the Allegheny structural front in Potter, Tioga, Bradford, Sullivan, Lycoming, Clinton and Centre counties. The Plateau fold belt in this area developed over a detachment in Upper Silurian Salina Group evaporites during the Permian Alleghanian Orogeny in response to north-northwest directed shortening. At the Allegheny structural front, a deep detachment in Cambrian shales that underlies the Valley and Ridge province to the south-southeast, ramps up-section through Cambro-Ordovician carbonates and Lower-Middle Silurian clastics to a shallow detachment in Upper Silurian evaporites. At the northeastern plunge of the Nittany Anticline (south and east of Williamsport, PA), only a small amount of slip is interpreted to have been transmitted into the foreland on the shallow Upper Silurian detachment. Instead most slip was consumed in fault-propagation folds immediately north of the Allegheny structural front. The Plateau fold belt, developed above the Upper Silurian evaporites, can be divided into structural domains based on fold characteristics. Domain 1 folds have short wavelengths and low amplitudes. Domain 2 salt-cored anticlines have long wavelengths and large amplitudes. Domain 3 comprises large synclines, located between Domain 2 anticlines. Halite originally beneath Domain 3 synclines is interpreted to have been mobilized, or evacuated, into the cores of adjacent Domain 2 anticlines during folding. Seismic data indicate that the base of the salt detachment underlying Plateau folds is a non-planar, stepped surface. Possible scenarios for the development of the non-planar detachment include: 1) mobilization of halite from an evaporite sequence that contained an originally non

  10. Vectors and malaria transmission in deforested, rural communities in north-central Vietnam

    PubMed Central

    2010-01-01

    Background Malaria is still prevalent in rural communities of central Vietnam even though, due to deforestation, the primary vector Anopheles dirus is uncommon. In these situations little is known about the secondary vectors which are responsible for maintaining transmission. Basic information on the identification of the species in these rural communities is required so that transmission parameters, such as ecology, behaviour and vectorial status can be assigned to the appropriate species. Methods In two rural villages - Khe Ngang and Hang Chuon - in Truong Xuan Commune, Quang Binh Province, north central Vietnam, a series of longitudinal entomological surveys were conducted during the wet and dry seasons from 2003 - 2007. In these surveys anopheline mosquitoes were collected in human landing catches, paired human and animal bait collections, and from larval surveys. Specimens belonging to species complexes were identified by PCR and sequence analysis, incrimination of vectors was by detection of circumsporozoite protein using an enzyme-linked immunosorbent assay. Results Over 80% of the anopheline fauna was made up of Anopheles sinensis, Anopheles aconitus, Anopheles harrisoni, Anopheles maculatus, Anopheles sawadwongporni, and Anopheles philippinensis. PCR and sequence analysis resolved identification issues in the Funestus Group, Maculatus Group, Hyrcanus Group and Dirus Complex. Most species were zoophilic and while all species could be collected biting humans significantly higher densities were attracted to cattle and buffalo. Anopheles dirus was the most anthropophilic species but was uncommon making up only 1.24% of all anophelines collected. Anopheles sinensis, An. aconitus, An. harrisoni, An. maculatus, An. sawadwongporni, Anopheles peditaeniatus and An. philippinensis were all found positive for circumsporozoite protein. Heterogeneity in oviposition site preference between species enabled vector densities to be high in both the wet and dry seasons

  11. Neogene north American-Caribbean plate boundary across Northern Central America: Offset along the polochic fault

    NASA Astrophysics Data System (ADS)

    Burkart, Burke

    1983-12-01

    The Polochic fault was a segment of the North American-Caribbean plate boundary across Central America in the Neogene. Its 130 km of left slip was previously determined by matching structures and stratigraphie outcrop patterns of northwest and central Guatemala across the fault. Additional support for the model and the youthfulness of the recorded offset comes from an essentially perfect match of major geomorphic features across the fault. A reconstruction process which eliminates 123 km of left slip brings together rivers and drainage divides that existed before the Polochic became active. With the reconstruction carried across the isthmus on an east-west fault the regional structural geology assumes the coherent pattern of a continuous orogenic belt whose geometry is compatible with the model of collisional tectonics centered on the Motagua "suture zone". Confined within this belt, narrowed to some 60 km by the reconstruction, lie the major Laramide thrusts, folds and tectonically emplaced serpentinites of Guatemala. Crystalline rocks of Guatemala re-join the Chiapas Massif and Paleozoic sedimentary rocks, exposed in the core of an almost-continuous anticlinorium, extend from southern Chiapas to Lake Izabal. The Polochic does not bend in eastern Guatemala but continues eastward to the Motagua fault where it dies. Westward drift of the northern block resulted in rifting which extended from eastern Guatemala into the Caribbean along the Cayman trough. The Honduras depression may represent an element of a triple junction along with the Polochic and Izabal-Cayman rift. The Polochic continues westward into the Pacific Ocean and offsets the Middle America trench. The Polochic has offset the Miocene volcanic belt of northern Central America, confirming the previous estimate of a Neogene time of movement. About 300 km of relative east-west Neogene displacement has been recorded on the Mid-Cayman rise, only 130 km of which can be accounted for across the Polochic. It is

  12. The Baltic Klint beneath the central Baltic Sea and its comparison with the North Estonian Klint

    NASA Astrophysics Data System (ADS)

    Tuuling, Igor; Flodén, Tom

    2016-06-01

    Along its contact with the Baltic Shield, the margin of the East European Platform reveals a well-developed, flooded terraced relief. The most striking and consistent set of escarpments at the contact of the Lower Palaeozoic calcareous and terrigenous rocks, known as the Baltic Klint (BK), extends from northwest of Russia to the Swedish island of Öland. Marine seismic reflection profiling in 1990-2004 revealed the central Baltic Sea Klint (BSK) section in detail and enabled comparison of its geology/geomorphology with a classical klint-section onshore, namely the North Estonian Klint (NEK). The conception of the BK onshore, which is based on the land-sea separating terraced relief in northern Estonia, is not fully applicable beneath the sea. Therefore, we consider that the BSK includes the entire terraced Cambrian outcrop. We suggest the term "Baltic Klint Complex" to include the well-terraced margin of the Ordovician limestone outcrop, which is weakly developed in Estonia. Because of a steady lithological framework of the bedrock layers across the southern slope of the Fennoscandian Shield, the central BSK in the western and the NEK in the eastern part of the Baltic Homocline have largely identical morphologies. The North Estonian Ordovician limestone plateau with the calcareous crest of the BK extends across the central Baltic Sea, whereas morphological changes/variations along the Klint base occur due to the east-westerly lithostratigraphic/thickness changes in the siliciclastic Cambrian sequence. The verge of the NEK, located some 30-50 m above sea level, starts to drop in altitude as its east-westerly course turns to northeast-southwest in western Estonia. Further westwards, the BK shifts gradually into southerly deepening (0.1-0.2°) layers as its crest drops to c. 150 m below sea level (b.s.l.) near Gotska Sandön. This course change is accompanied by a considerable decrease in thickness of the platform sedimentary cover, as below the central Baltic Sea the

  13. Application of ICT (Information and Communication Technology) in the Management of Universities in the North-Central State of Nigeria

    ERIC Educational Resources Information Center

    Oboegbulem, Angie Ijeoma; Godwin, Ochai

    2013-01-01

    This study investigated the application of ICT (information and communication technology) in the management of universities in the north-central Nigeria. The study was a descriptive survey. The population of the study comprised 1,294 respondents in federal and state universities (763 in federal and 531 in state universities). The sample size…

  14. A 13-WEEK COMPARISON OF PASSIVE AND CONTINUOUS OZONE MONITORS AT FORESTED SITES IN NORTH-CENTRAL PENNSYLVANIA

    EPA Science Inventory

    Ogawa passive 03 samplers were used in a 13-233k study (June 1-September 1, 1999) involving 11 forested and mountaintop sites in north-central Pennsylvania. Four of the sites were collocated with TECO model 49 O3 analyzers. A significant correlation (p<0.0001) was found for 2...

  15. Host-seeking height preferences of Aedes albopictus (Diptera: Culicidae) in North-central Florida suburban and sylvatic locales

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The response of Aedes albopictus to the BG-Sentinel™, Omni-directional-Fay-Prince and Mosquito Magnet-X traps was evaluated in four suburban and four sylvatic habitats in North-Central Florida to ascertain potential height preference of this species. These traps, which are primarily designed to att...

  16. Ovitrap Efficacy Using Plant Infusions to Monitor Vertical Distribution of Aedes albopictus Skuse (Diptera: Culicidae) in North-Central Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The response of Aedes albopictus to ovitraps containing water, oak or oak-pine was evaluated in four suburban and four sylvatic habitats in North-Central Florida to ascertain potential egg-laying heights. A total of 48 ovitraps were suspended at 1 and 6 meters and monitored weekly for five months....

  17. Languages of North, Central, and South America. A Survey of Materials for the Study of the Uncommonly Taught Languages.

    ERIC Educational Resources Information Center

    Johnson, Dora E.; And Others

    This is an annotated bibliography of basic tools of access for the study of the uncommonly taught languages of North, Central, and South America. It is one of eight fascicles which constitute a revision of "A Provisional Survey of Materials for the Study of the Neglected Languages" (CAL 1969). The emphasis is on materials for the adult learner…

  18. "El Miedo y El Hambre": Understanding the Familial, Social, and Educational Realities of Undocumented Latino Families in North Central Indiana

    ERIC Educational Resources Information Center

    Viramontez Anguiano, Ruben P.; Lopez, Anayeli

    2012-01-01

    This study explored how different ecological factors, within and outside the family, affected the educational success of the children of undocumented families. The sample consisted of 63 immigrant Latino parents (40 families) who resided in North Central Indiana. This study utilized an ethnographic research design. Findings demonstrated that…

  19. Re-Engineering Vocational and Technical Education (VTE) for Sustainable Development in North Central Geo-Political Zone, Nigeria

    ERIC Educational Resources Information Center

    Sofoluwe, Abayomi Olumade

    2013-01-01

    The purpose of the study is to re-engineer vocational and technical education for sustainable development in the North Central Geo-Political Zone in Nigeria. The research design adopted was a survey inferential type. Stratified random was used to select 36 schools out of 98 schools while 920 students out of 3680 students were sampled. The data…

  20. Working Together to Make a Difference in Rural America: North Central Regional Center for Rural Development, 2010 Annual Report

    ERIC Educational Resources Information Center

    North Central Regional Center for Rural Development, 2011

    2011-01-01

    The North Central Regional Center for Rural Development (NCRCRD) is one of four regional centers in the United States that have worked to improve the quality of life in rural communities for nearly 40 years. With funding from the USDA National Institute of Food and Agriculture and the land-grant universities in our 12-state region, the NCRCRD…

  1. Expansion of Economic Base Analysis: Labor Availability in North-Central New Mexico. Research Report No. 264.

    ERIC Educational Resources Information Center

    Carruthers, Garrey E.; And Others

    Estimates of the number of persons willing to commute, at alternative wage rates, to job opportunities in north-central New Mexico have been based on results of basic research in the region and 1970 census data. Expressed willingness to commute and socio-economic characteristics data were accumulated from a regional survey of 643 households. The…

  2. An Analysis of the North Central United States with Particular Reference to Vocational Training Needs and Opportunities for Rural Students.

    ERIC Educational Resources Information Center

    Hobbs, Daryl

    Recent changes in patterns of population location, industrial employment, and technology in the north central United States have produced implications for vocational education in rural areas. Missouri has greater social, cultural, demographic, and economic diversity than other states in the region, but is representative of the area for purposes of…

  3. Impact of Sustainable Agriculture on Secondary School Agricultural Education Teachers and Programs in the North Central Region.

    ERIC Educational Resources Information Center

    Agbaje, Kehinde Aderemi Ajaiyeoba; Martin, Robert A.; Williams, David L.

    2001-01-01

    Responses from 298 of 600 secondary agriculture teachers in north central United States revealed limited impact of sustainable agriculture. Most teachers had neutral perceptions; a moderate number taught it, but not from a systems perspective. However, related agronomy topics were taught, providing a possible foundation for future inclusion of…

  4. A Comparative Economic Analysis of North-Central New Mexico. New Mexico Agricultural Experiment Station Research Report 211.

    ERIC Educational Resources Information Center

    Carruthers, Garrey E.; Eastman, Clyde

    North-Central New Mexico has many of the problems common to other rural areas. Unemployment and underemployment rates tend to be high and per capita income relatively low. This study evaluated regional economic performance over a 19-year period (1949-1968) as compared to other regions and the nation. Shift analysis (a means of examining regional…

  5. A THIRTEEN-WEEK COMPARISON OF PASSIVE AND CONTINUOUS OZONE MONITORS AT FORESTED SITES IN NORTH-CENTRAL PENNSYLVANIA

    EPA Science Inventory

    Ogawa passive 03 samplers were used in a 13-233k study (June 1-September 1, 1999) involving 11 forested and mountaintop sites in north-central Pennsylvania. Four of the sites were collocated with TECO model 49 O3 analyzers. A significant correlation (p<0.0001) was found for 24-...

  6. The Ritual "Play of the Congos" of North-Central Panama: Its Sociolinguistic Implications. Sociolinguistic Working Paper Number 85.

    ERIC Educational Resources Information Center

    Joly, Luz Graciela

    An excerpt from the "Play of the Congos," given in Congo, Spanish, and English, exemplifies the sociolinguistic features of the combined play and ritual language used by the Afro-Hispanic population in the Caribbean region of the Costa Abajo in north-central Panama. The sociolinguistic norms are an important part of the "regulation of the play,"…

  7. Calculating the ecosystem service of water storage in isolated wetlands using LiDAR in north central Florida, USA (presentation)

    EPA Science Inventory

    This study used remotely-sensed Light Detection and Ranging (LiDAR) data to estimate potential water storage capacity of isolated wetlands in north central Florida. The data were used to calculate the water storage potential of >8500 polygons identified as isolated wetlands. We f...

  8. Calculating the ecosystem service of water storage in isolated wetlands using LIDAR in north central Florida, USA

    EPA Science Inventory

    This study used remotely-sensed Light Detection and Ranging (LiDAR) data to estimate potential water storage capacity of isolated wetlands in north central Florida. The data were used to calculate the water storage potential of >8500 polygons identified as isolated wetlands. We ...

  9. Central-north China precipitation as reconstructed from the Qing dynasty: Signal of the Antarctic Atmospheric Oscillation

    NASA Astrophysics Data System (ADS)

    Wang, Huijun; Fan, Ke

    2005-12-01

    Based on the long-term Central-north China precipitation (CNCP) time series reconstructed from the Qing Dynasty Official Document, the relationship between CNCP and the Antarctic Atmospheric Oscillation (AAO) in June-July is examined. The analysis yields a (significant) negative correlation of -0.22. The signal of AAO in CNCP is further studied through analyses of the atmospheric general circulation variability related to AAO. It follows that AAO-related variability of convergence and convection over the tropical western Pacific can exert impact on the circulation condition and precipitation in north China (actually, the precipitation in the Yangtze River Valley as well) through atmospheric teleconnection known as the East Asia-Pacific (or Pacific-Japan) teleconnection wave pattern. There is also an AAO-connected wave train in the vorticity field at high troposphere over Eurasia, providing an anti-cyclonic circulation in central-north China favorable to the decline of precipitation in positive phase of AAO.

  10. Fine-scale distribution modeling of avian malaria vectors in north-central Kansas.

    PubMed

    Ganser, Claudia; Gregory, Andrew J; McNew, Lance B; Hunt, Lyla A; Sandercock, Brett K; Wisely, Samantha M

    2016-06-01

    Infectious diseases increasingly play a role in the decline of wildlife populations. Vector-borne diseases, in particular, have been implicated in mass mortality events and localized population declines are threatening some species with extinction. Transmission patterns for vector-borne diseases are influenced by the spatial distribution of vectors and are therefore not uniform across the landscape. Avian malaria is a globally distributed vector-borne disease that has been shown to affect endemic bird populations of North America. We evaluated shared habitat use between avian malaria vectors, mosquitoes in the genus Culex and a native grassland bird, the Greater Prairie-Chicken (Tympanuchus cupido), by (1) modeling the distribution of Culex spp. occurrence across the Smoky Hills of north-central Kansas using detection data and habitat variables, (2) assessing the occurrence of these vectors at nests of female Greater Prairie-Chickens, and (3) evaluating if shared habitat use between vectors and hosts is correlated with malarial infection status of the Greater Prairie-Chicken. Our results indicate that Culex occurrence increased at nest locations compared to other available but unoccupied grassland habitats; however the shared habitat use between vectors and hosts did not result in an increased prevalence of malarial parasites in Greater Prairie-Chickens that occupied habitats with high vector occurrence. We developed a predictive map to illustrate the associations between Culex occurrence and infection status with malarial parasites in an obligate grassland bird that may be used to guide management decisions to limit the spread of vector-borne diseases. PMID:27232133

  11. Three-dimensional circulation structures leading to heavy summer rainfall over central North China

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Yu, Rucong; Li, Jian; Yuan, Weihua

    2016-04-01

    Using daily and hourly rain gauge records and Japanese 25 year reanalysis data over 30 years, this work reveals two major circulation structures leading to heavy summer rainfall events in central North China (CNC), and further analyzes the effects of the circulations on these rainfall events. One circulation structure has an extensive upper tropospheric warm anomaly (UTWA) covering North China (NC). By strengthening the upper anticyclonic anomaly and lower southerly flows around NC, the UTWA plays a positive role in forming upper level divergence and lower level moisture convergence. As a result, the warm anomalous circulation has a solid relationship with large-scale, long-duration rainfall events with a diurnal peak around midnight to early morning. The other circulation structure has an upper tropospheric cold anomaly (UTCA) located in the upper stream of NC. Contributed to by the UTCA, a cold trough appears in the upper stream of NC and an unstable configuration with upper (lower) cold (warm) anomalies forms around CNC. Consequently, CNC is covered by strong instability and high convective energy, and the cold anomalous circulation is closely connected with local, short-duration rainfall events concentrated from late afternoon to early nighttime. The close connections between circulation structures and typical rainfall events are confirmed by two independent converse analysis processes: from circulations to rainfall characteristics, and from typical rainfall events to circulations. The results presented in this work indicate that the upper tropospheric temperature has significant influences on heavy rainfall, and thus more attention should be paid to the upper tropospheric temperature in future analyses.

  12. Two major circulation structures leading to heavy summer rainfall over central North China

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Li, Jian; Yu, Rucong; Yuan, Weihua

    2015-05-01

    Using daily and hourly rain gauge records and Japanese 25 year reanalysis data over 30 years, this paper reveals two major circulation structures leading to heavy summer rainfall events in central North China (CNC), and further analyzes the effects of the circulations on these rainfall events. One circulation structure has an extensive upper tropospheric warm anomaly (UTWA) covering North China (NC). By strengthening the upper anticyclonic anomaly and lower southerly flows around NC, the UTWA plays a positive role in forming upper level divergence and lower level moisture convergence. As a result, the warm anomalous circulation has a solid relationship with large-scale, long-duration rainfall events with a diurnal peak around midnight to early morning. The other circulation structure has an upper tropospheric cold anomaly (UTCA) located in the upper stream of NC. Contributed to by the UTCA, a cold trough appears in the upper stream of NC and an unstable configuration with upper (lower) cold (warm) anomalies forms around CNC. Consequently, CNC is covered by strong instability and high convective energy, and the cold anomalous circulation is closely connected with local, short-duration rainfall events concentrated from late afternoon to early nighttime. The close connections between circulation structures and typical rainfall events are confirmed by two independent converse analysis processes: from circulations to rainfall characteristics, and from typical rainfall events to circulations. The results presented in this paper indicate that the upper tropospheric temperature has significant influences on heavy rainfall, and thus more attention should be paid to the upper tropospheric temperature in future analyses.

  13. Proposal for a comprehensive vertical datum for North America, Central America and the Caribbean

    NASA Astrophysics Data System (ADS)

    Smith, D. A.; Roman, D. R.; Childers, V. A.; Eckl, M. C.; Youngman, M.

    2013-05-01

    As part of its Ten Year Strategic Plan (2013-2023), the National Geodetic Survey (NGS) of the USA is planning to replace the North American Vertical Datum of 1988 (NAVD 88) by the year 2022. The replacement vertical datum will be defined through a gravimetric geoid model and accessed via GNSS technology, in direct contrast to the definition and access of NAVD 88, which is through passive, generally unmonitored benchmarks connected through geodetic leveling. A USA-Canada-Mexico joint effort is underway to compute a single geoid model by 2022 for the entire region, which can be adopted as the vertical datum reference surface by all countries within the area. The proposed area ranges from the North Pole to the Equator and from the Aleutian Islands (in the west) to the islands of Newfoundland (in the east). As such, the entirety of the Caribbean Sea, all of Central America, all of Hawaii, plus parts of Greenland and South America will be covered. This will allow one singular, unified vertical datum to be accessible to every country in the region, alleviating the need for island-by-island vertical datums as is currently the case. A major component of the geoid modeling effort is NGS's GRAV-D project (Gravity for the Redefinition of the American Vertical Datum). That project has a two-fold approach: First, to collect a static, accurate "snapshot" of the entire gravity field. This is primarily being done through airborne gravity collection over the USA and its territories, as well as through improvements in and additions to terrestrial data holdings. A second, long-term effort of GRAV D is to monitor the geoid over time. This talk will discuss the prospects of improving the static gravity field holdings outside of the USA and its territories, including a discussion on existing holdings, data gaps and NGS's desire for potential collaborations with interested countries in the region both before and after the 2022 datum change.

  14. Natural groundwater recharge in an upland area of central North Dakota, U.S.A.

    USGS Publications Warehouse

    Rehm, B.W.; Moran, S.R.; Groenewold, G.H.

    1982-01-01

    The magnitude of groundwater recharge to coal aquifers in a 150-km2 area in west-central North Dakota was determined using three separate approaches: (1) the net water level rise in water-table wells; (2) calculations of the fluid flux between nested piezometers, using the Darcy equation and measured values of hydraulic conductivity and vertical gradients; and (3) evaluation of the inputs to and outputs from the coal aquifer, using a steady-state control volume approach in which the aquifer was divided into semi-rectangular cells bounded by equipotential lines and flow lines. Measurements of potential gradients and hydraulic conductivity permitted indirect determination of all components of flow into and out of the cell except the recharge input, which was determined by difference. All methods yielded consistent results on the order of 0.04-0.01 m yr.-1 These values, which represent 2-9% of the annual precipitation, are consistent with results of other studies on recharge throughout the prairies of North America. Evaluation of site hydrology and stable-isotope data indicates that recharge is restricted in both time and place. Most recharge occurs in late spring and in the fall following heavy rainfall events. During these seasons the ground is not frozen and vegetation is not transpiring large amounts of water. Some recharge may occur during very heavy localized summer storms, but it is not considered volumetrically significant. Major permanent depressions on the site are a source of significant recharge. In addition, the extensive area of ephemeral standing water bodies that result from snowmelt can produce significant amounts of infiltration over the entire site. ?? 1982.

  15. Perchlorate in pleistocene and holocene groundwater in North-Central New Mexico

    USGS Publications Warehouse

    Plummer, L.N.; Böhlke, J.K.; Doughten, M.W.

    2006-01-01

    Groundwater from remote parts of the Middle Rio Grande Basin in north-central New Mexico has perchlorate (ClO4-) concentrations of 0.12-1.8 ??g/L Because the water samples are mostly preanthropogenic in age (0-28 000 years) and there are no industrial sources in the study area, a natural source of the ClO4- is likely. Most of the samples have Br-, Cl-, and SO42- concentrations that are similar to those of modern bulk atmospheric deposition with evapotranspiration (ET) factors of about 7-40. Most of the ET values for Pleistocene recharge were nearly twice that for Holocene recharge. The NO3-/Cl- and ClO4-/Cl- ratios are more variable than those of Br -/Cl- or SO42-/Cl-. Samples thought to have recharged under the most arid conditions in the Holocene have relatively high NO3-/Cl- ratios and low ??15N values (+1 per mil (???)) similar to those of modern bulk atmospheric N deposition. The ??18O values of the NO 3- (-4 to 0 ???) indicate that atmospheric N0 3- was not transmitted directly to the groundwater but may have been cycled in the soils before infiltrating. Samples with nearly atmospheric NO3-/Cl- ratios have relatively high ClO4- concentrations (1.0-1.8 ??g/L) with a nearly constant ClO4-/Cl- mole ratio of (1.4 ?? 0.1) ?? 10-4, which would be consistent with an average ClO 4- concentration of 0.093 ?? 0.005 ??g/L in bulk atmospheric deposition during the late Holocene in north-central NM. Samples thought to have recharged underwetter conditions have higher ??15N values (+3 to +8 ???), lower N03-/Cl- ratios, and lower ClO4-/Cl- ratios than the ones most likely to preserve an atmospheric signal. Processes in the soils that may have depleted atmospherically derived NO3- also may have depleted ClO4- to varying degrees prior to recharge. If these interpretations are correct, then ClO4- concentrations of atmospheric origin as high as 4 ??g/L are possible in preanthropogenic groundwater in parts of the Southwest where ET approaches a factor of 40. Higher ClO4

  16. Electrical conductivity of mantle in the North Central region of Nigeria

    NASA Astrophysics Data System (ADS)

    Obiora, Daniel N.; Okeke, Francisca N.; Yumoto, K.

    2015-01-01

    The mantle electrical conductivity profile of the North Central region of Nigeria was determined using the quiet day ionospheric current variations (Sq). The employed magnetic averaged hourly data were obtained from Magnetic Data Acquisition System (MAGDAS) ground based observatories at two Nigerian stations located at Ilorin (8°30‧N, 4°33‧E) and Abuja (8°59‧N, 7°23‧E) for the year 2009 and 2010. The magnetometer data from Pankshin (9°20‧N, 9°27‧E) and Katsina-Ala (7°10‧N, 9°17‧E) for the same years were equally employed. The separation of both the internal and external field contributions to the Sq variations was successfully carried out employing spherical harmonic analysis (SHA). Transfer function was performed in computing the conductivity-depth profile for North Central region of Nigeria from the paired external and internal coefficients of the SHA. The conductivity value of approximately 0.039 S/m was estimated at a depth of 100 km which rose gradually to 0.087 S/m at 207 km depth and 0.142 S/m at 367 km (close to the base of upper mantle). Subsequently, the conductivity profile continued rising to a value of 0.144 S/m at 442 km, 0.164 S/m at 653 km and 0.174 S/m at 710 km. Finally, value of approximately 0.195 S/m at a depth of 881 km and 0.240 S/m at 1100 km depth were recorded at the lower mantle with no indication of leveling off. Some evidence of discontinuities near 100-214 km, 214-420 km, 420-640 km, 640-900 km and 900-1100 km were clearly obvious. The sharp increase in conductivity from about 100 km depth to 230 km was interpreted to correspond to the global seismic low velocity zone - the asthenosphere.

  17. The Use of Ground Penetrating Radar to Exploring Sedimentary Ore In North-Central Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Almutairi, Yasir; Almutair, Muteb

    2015-04-01

    Ground Penetrating Radar (GPR) is a non-destructive geophysical method that provides a continuous subsurface profile, without drilling. This geophysical technique has great potential in delineating the extension of bauxites ore in north-central Saudi Arabia. Bauxite is from types sedimentary ores. This study aim to evaluate the effectiveness of Ground Penetrating Radar (GPR) to illustrate the subsurface feature of the Bauxite deposits at some selected mining areas north-central Saudi Arabia. Bauxite is a heterogeneous material that consists of complex metals such as alumina and aluminum. An efficient and cost-effect exploration method for bauxite mine in Saudi Arabia is required. Ground penetrating radar (GPR) measurements have been carrying out along outcrop in order to assess the potential of GPR data for imaging and characterising different lithological facies. To do so, we have tested different antenna frequencies to acquire the electromagnetic signals along a 90 m profile using the IDS system. This system equipped with a 25 MHz antenna that allows investigating the Bauxite layer at shallow depths where the clay layers may existed. Therefore, the 25 MHz frequency antenna has been used in this study insure better resolution of the subsurface and to get more penetration to image the Bauxite layer. After the GPR data acquisition, this data must be processed in order to be more easily visualized and interpreted. Data processing was done using Reflex 6.0 software. A series of tests were carried out in frequency filtering on a sample of radar sections, which was considered to better represent the entire set of data. Our results indicated that the GPR profiling has a very good agreement for mapping the bauxite layer depth at range of 7 m to 11 m. This study has emphasized that the high-resolution GPR method is the robust and cost-effect technique to map the Bauxite layer. The exploration of Bauxite resource using the GPR technique could reduce the number of holes to

  18. Perchlorate in pleistocene and holocene groundwater in north-central New Mexico.

    PubMed

    Plummer, L Niel; Böhlke, John Karl; Doughten, Michael W

    2006-03-15

    Groundwater from remote parts of the Middle Rio Grande Basin in north-central New Mexico has perchlorate (ClO4-) concentrations of 0.12-1.8 micro/L. Because the water samples are mostly preanthropogenic in age (0-28000 years) and there are no industrial sources in the study area, a natural source of the ClO4- is likely. Most of the samples have Br-, Cl-, and SO4(2-) concentrations that are similar to those of modern bulk atmospheric deposition with evapotranspiration (ET) factors of about 7-40. Most of the ET values for Pleistocene recharge were nearly twice that for Holocene recharge. The N03-/Cl- and CIO-/Cl-ratios are more variable than those of Br-/Cl- or S04(2-)/Cl-. Samples thought to have recharged under the most arid conditions in the Holocene have relatively high N03-/Cl- ratios and low delta 15N values (+1 per mil (% per thousand)) similar to those of modern bulk atmospheric N deposition. The delta 18O values of the N03- (-4 to 0% per thousand) indicate that atmospheric N03- was not transmitted directly to the groundwater but may have been cycled in the soils before infiltrating. Samples with nearly atmospheric N03-/CI- ratios have relatively high Cl04- concentrations (1.0-1.8 ug/L) with a nearly constant Cl04-/CI- mole ratio of (1.4 +/- 0.1) x 10(-4), which would be consistent with an average Cl04-concentration of 0.093 0.005 ,ug/L in bulk atmospheric deposition during the late Holocene in north-central NM. Samples thought to have recharged under wetter conditions have higher delta 15N values (+3 to +8 % per thousando), lower NO3-/Cl- ratios, and lower ClO4-/Cl- ratios than the ones most likely to preserve an atmospheric signal. Processes in the soils that may have depleted atmospherically derived NO3-also may have depleted ClO4- to varying degrees prior to recharge. If these interpretations are correct, then ClO4- concentrations of atmospheric origin as high as 4 microg/L are possible in preanthropogenic groundwater in parts of the Southwest where ET

  19. Micropaleontologic record of Quaternary paleoenvironments in the Central Albemarle Embayment, North Carolina, U.S.A.

    USGS Publications Warehouse

    Culver, Stephen J.; Farrell, Kathleen M.; Mallinson, David J.; Willard, Debra A.; Horton, Benjamin P.; Riggs, Stanley R.; Thieler, E. Robert; Wehmiller, John F.; Parham, Peter; Snyder, Scott W.; Hillier, Caroline

    2011-01-01

    To understand the temporal and spatial variation of eustatic sea-level fluctuations, glacio-hydro-isostacy, tectonics, subsidence, geologic environments and sedimentation patterns for the Quaternary of a passive continental margin, a nearly complete stratigraphic record that is fully integrated with a three dimensional chronostratigraphic framework, and paleoenvironmental information are necessary. The Albemarle Embayment, a Cenozoic regional depositional basin in eastern North Carolina located on the southeast Atlantic coast of the USA, is an ideal setting to unravel these dynamic, interrelated processes.Micropaleontological data, coupled with sedimentologic, chronostratigraphic and seismic data provide the bases for detailed interpretations of paleoenvironmental evolution and paleoclimates in the 90. m thick Quaternary record of the Albemarle Embayment. The data presented here come from a transect of cores drilled through a barrier island complex in the central Albemarle Embayment. This area sits in a ramp-like setting between late Pleistocene incised valleys.The data document the episodic infilling of the Albemarle Embayment throughout the Quaternary as a series of transgressive-regressive (T-R) cycles, characterized by inner shelf, midshelf, and shoreface assemblages, that overlie remnants of fluvial to estuarine valley-fill. Barrier island and marginal marine deposits have a low preservation potential. Inner to mid-shelf deposits of the early Pleistocene are overlain by similar middle Pleistocene shelf sediments in the south of the study area but entirely by inner shelf deposits in the north. Late Pleistocene marine sediments are of inner shelf origin and Holocene deposits are marginal marine in nature. Pleistocene marine sediments are incised, particularly in the northern half of the embayment by lowstand paleovalleys, partly filled by fluvial/floodplain deposits and in some cases, overlain by remnants of transgressive estuarine sediments. The shallowing

  20. Vitrinite reflectance data for Cretaceous marine shales and coals in the Bighorn Basin, north-central Wyoming and south-central Montana

    USGS Publications Warehouse

    Pawlewicz, Mark J.; Finn, Thomas M.

    2012-01-01

    The Bighorn Basin is a large Laramide (Late Cretaceous through Eocene) structural and sedimentary basin that encompasses about 10,400 square miles in north-central Wyoming and south-central Montana. The purpose of this report is to present new vitrinite reflectance data collected from Cretaceous marine shales and coals in the Bighorn Basin to better characterize the thermal maturity and petroleum potential of these rocks. Ninety-eight samples from Lower Cretaceous and lowermost Upper Cretaceous strata were collected from well cuttings from wells stored at the U.S. Geological Survey (USGS) Core Research Center in Lakewood, Colorado.

  1. GIS Representation of Coal-Bearing Areas in North, Central, and South America

    USGS Publications Warehouse

    Tewalt, Susan J.; Kinney, Scott A.; Merrill, Matthew D.

    2008-01-01

    Worldwide coal consumption and international coal trade are projected to increase in the next several decades (Energy Information Administration, 2007). A search of existing literature indicates that in the Western Hemisphere, coal resources are known to occur in about 30 countries. The need exists to be able to depict these areas in a digital format for use in Geographic Information System (GIS) applications at small scales (large areas) and in visual presentations. Existing surficial geology GIS layers of the appropriate geologic age have been used as an approximation to depict the extent of coal-bearing areas in North, Central, and South America, as well as Greenland (fig. 1). Global surficial geology GIS data were created by the U.S. Geological Survey (USGS) for use in world petroleum assessments (Hearn and others, 2003). These USGS publications served as the major sources for the selection and creation of polygons to represent coal-bearing areas. Additional publications and maps by various countries and agencies were also used as sources of coal locations. GIS geologic polygons were truncated where literature or hardcopy maps did not indicate the presence of coal. The depicted areas are not adequate for use in coal resource calculations, as they were not adjusted for geologic structure and do not include coal at depth. Additionally, some coal areas in Central America could not be represented by the mapped surficial geology and are shown only as points based on descriptions or depictions from scientific publications or available maps. The provided GIS files are intended to serve as a backdrop for display of coal information. Three attributes of the coal that are represented by the polygons or points include geologic age (or range of ages), published rank (or range of ranks), and information source (published sources for age, rank, or physical location, or GIS geology base).

  2. Evaluation of groundwater quality in a rural community in North Central of Nigeria.

    PubMed

    Sojobi, Adebayo Olatunbosun

    2016-03-01

    Evaluation of water quality of nine boreholes and three open hand-dug wells in a rural community in North Central Nigeria revealed relative abundance of cations Na > k > Ca > Mg > Zn > Pb and anions Cl(-) > PO4(2-) > SO4(2-) > NO3(-) in the boreholes and cations Ca > Na > K > Mg > Pb and anions NO3(-)  > PO4(2-)  > SO4(2-) > Cl(-) in the wells. The major contaminants exceeding SON and WHO permissible limits were NO3(-) , Mg, TH, pH and Mg, Pb, TH, pH and DO in the wells and boreholes, respectively. They are attributable to anthropogenic sources such as domestic waste water and poor waste disposal and natural sources such as mineral dissolution from clayey aquifer which made the acidic groundwater unsuitable for consumption unless they are appropriately treated. Correlation studies revealed existence of three major mineral groups in the aquifer Ca-Fe group, Na-Mg group, Zn-K group, as well as a minor group Pb-group, and they determine the chemical composition of the groundwater and the ionic exchange between the groundwater and mineral-bearing clayey aquifer. In order to curb microbial contamination by Enterobacter aerogenes and Escherichia coli, it is recommended that proper latrines and drainages be provided while domesticated animals should be restricted from boreholes and well. Further, treatment with water guard and pur purifier is recommended. PMID:26915740

  3. Isostatic Gravity Map of the Battle Mountain 30 x 60 Minute Quadrangle, North Central Nevada

    USGS Publications Warehouse

    Ponce, D.A.; Morin, R.L.

    2000-01-01

    Introduction Gravity investigations of the Battle Mountain 30 x 60 minute quadrangle were begun as part of an interagency effort by the U.S. Geological Survey (USGS) and the Bureau of Land Management to help characterize the geology, mineral resources, hydrology, and ecology of the Humboldt River Basin in north-central Nevada. The Battle Mountain quadrangle is located between 40?30' and 41?N. lat. and 116? and 117?W. long. This isostatic gravity map of the Battle Mountain quadrangle was prepared from data from about 1,180 gravity stations. Most of these data are publicly available on a CD-ROM of gravity data of Nevada (Ponce, 1997) and in a published report (Jewel and others, 1997). Data from about 780 gravity stations were collected by the U.S. Geological Survey since 1996; data from about 245 of these are unpublished (USGS, unpub. data, 1998). Data collected from the 400 gravity stations prior to 1996 are a subset of a gravity data compilation of the Winnemucca 1:250,000-scale quadrangle described in great detail by Wagini (1985) and Sikora (1991). This detailed information includes gravity meters used, dates of collection, sources, descriptions of base stations, plots of data, and a list of principal facts. A digital version of the entire data set for the Battle Mountain quadrangle is available on the World Wide Web at: http://wrgis.wr.usgs.gov/docs/gump/gump.html

  4. Pharmaceuticals and other organic chemicals in selected north-central and northwestern Arkansas streams

    USGS Publications Warehouse

    Haggard, B.E.; Galloway, J.M.; Green, W.R.; Meyer, M.T.

    2006-01-01

    Recently, our attention has focused on the low level detection of many antibiotics, pharmaceuticals, and other organic chemicals in water resources. The limited studies available suggest that urban or rural streams receiving wastewater effluent are more susceptible to contamination. The purpose of this study was to evaluate the occurrence of antibiotics, pharmaceuticals, and other organic chemicals at 18 sites on seven selected streams in Arkansas, USA, during March, April, and August 2004. Water samples were collected upstream and downstream from the influence of effluent discharges in northwestern Arkansas and at one site on a relatively undeveloped stream in north-central Arkansas. At least one antibiotic, pharmaceutical, or other organic chemical was detected at all sites, except at Spavinaw Creek near Mayesville, Arkansas. The greatest number of detections was observed at Mud Creek downstream from an effluent discharge, including 31 pharmaceuticals and other organic chemicals. The detection of these chemicals occurred in higher frequency at sites downstream from effluent discharges compared to those sites upstream from effluent discharges; total chemical concentration was also greater downstream. Wastewater effluent discharge increased the concentrations of detergent metabolites, fire retardants, fragrances and flavors, and steroids in these streams. Antibiotics and associated degradation products were only found at two streams downstream from effluent discharges. Overall, 42 of the 108 chemicals targeted in this study were found in water samples from at least one site, and the most frequently detected organic chemicals included caffeine, phenol, para-cresol, and acetyl hexamethyl tetrahydro naphthalene (AHTN). ?? ASA, CSSA, SSSA.

  5. Detection of nonylphenol and persistent organic pollutants in fish from the North Pacific Central Gyre.

    PubMed

    Gassel, Margy; Harwani, Suhash; Park, June-Soo; Jahn, Andrew

    2013-08-15

    Despite scientific and public concern, research on food web contamination from chemicals in plastic is limited, and distinguishing plastic sources from prey remains a challenge. We analyzed juvenile yellowtail (Seriola lalandi) from the North Pacific Central Gyre for plastic ingestion and tissue concentrations of persistent organic pollutants and nonionic surfactants to investigate potential contamination from plastic exposure. Ingestion of synthetic debris occurred in ~10% of the sample population. PCBs and DDTs were 352±240 (mean±SD) and 1425±1118 ng/g lw, respectively. PBDEs were 9.08±10.6 ng/g lw, with BDEs-47, 99, and 209 representing 90% of PBDEs. Nonylphenol (NP) was detected in one-third of the yellowtail with a mean of 52.8±88.5 ng/g ww overall and 167±72.3 ng/g ww excluding non-detects. Because environmental NP is strongly associated with wastewater treatment effluents, long-range transport is unlikely, and NP was previously measured in gyre plastic, we concluded that plastic-mediated exposure best explained our findings of NP in yellowtail. PMID:23746941

  6. Hydrology and plant survival in excavated depressions near an earthen dam in north-central Texas

    NASA Astrophysics Data System (ADS)

    Williams, Lynde L.; Hudak, Paul F.

    2005-09-01

    This investigation examined plant survival and water sources for small depressions excavated to build an earthen dam and nature trail in north-central Texas, USA. These “inadvertent wetlands” occupy part of an outdoor education facility, overlying alluvial deposits of the Trinity River. A large lake behind the earthen dam strongly influences surface water and groundwater levels in the area. Excavated depressions receive direct precipitation, runoff, and groundwater inputs, losing water by seepage and evapotranspiration. Hydroperiods varied with location and water input: excavations receiving groundwater held water year round; others periodically desiccated. Groundwater-fed depressions had higher salinity; however, the highest average value (1,304 μS/cm) was within the freshwater range. A total of 66 to 75% of emergent and floating wetland species planted in three depressions survived after 2 years. The developing wetlands appear viable under hydrologic conditions typical of the study period. Ultimately, variable hydroperiods among wetlands, and water level fluctuations within individual wetlands, may foster diverse plant-species compositions. Depressed lake levels following long-term drought or increased water demands pose the greatest threat to the developing wetlands.

  7. Pattern and determinants of morbidity among people living with HIV/AIDS in North Central Nigeria.

    PubMed

    Olaleye, Adeniyi; Ogwumike, F O

    2013-02-01

    The study investigated the nature of self-reported morbidity and determinants of health status among people living with HIV/AIDS (PLWHA) in North Central Nigeria. A multi-stage cluster sampling method was used to select 1,056 adult PLWHA from 60 community-based support groups as respondents to a structured questionnaire. Based on health production function, health status was specified as a function of individual/household characteristics, health-related behaviours and genetic endowment. Descriptive statistics showed that more than half (52.8%, n=558) of the PLWHA reported illness in the last four weeks. The poor, widows and divorcees, and those living in rural areas reported illness more than their non-poor, married and urban counterparts. Logistic regression results indicated that self reported mobility was associated with rural residence (p=.005), greater use of condom (p=.013), and lower CD4 count (p=.007). Programs to promote positive living and access to health care services among PLWHA in Nigeria, especially in rural areas, are recommended. PMID:23377732

  8. Hydrology and geochemistry of thermal ground water in southwestern Idaho and north-central Nevada

    SciTech Connect

    Young, H.W.; Lewis, R.E.

    1982-01-01

    Chemical analyses of water from 12 wells and 9 springs indicate that nonthermal waters are a calcium bicarbonate type; thermal waters are a sodium carbonate or bicarbonate type. Chemical geothermometers indicate probable maximum reservoir temperatures are near 100/sup 0/ Celsius. Concentration of tritium in the thermal water is near zero. Depletion of stable isotopes in the hot waters relative to present-day meteoric waters indicates recharge to the system probably occurred when the climate averaged 3/sup 0/ to 5/sup 0/ Celsius colder than at present. Temperatures about 3.5/sup 0/ Celsius colder than at present occurred during periods of recorded Holocene glacial advances and indicate a residence time of water in the system of at least several thousand years. Residence time calculated on the basis of reservoir volume and thermal-water discharge is 3400 to 6800 years for an effective reservoir porosity of 0.05 and 0.10, respectively. Preliminary analyses of carbon-14 determinations indicate an age of the hot waters of about 18,000 to 25,000 years. The proposed conceptual model for the area is one of an old system, where water has circulated for thousands, even tens of thousands, of years. Within constraints imposed by the model described, reservoir thermal energy for the geothermal system in southwestern Idaho and north-central Nevada is about 130 x 10/sup 18/ calories.

  9. Geology of the Flat Swamp Mountain caldera and related rocks, Carolina slate belt, central North Carolina

    SciTech Connect

    Butler, J.R. . Dept. of Geology)

    1994-03-01

    The Flat Swamp Member (FSM) of the Cid Formation (Late Proterozoic) and related volcanogenic deposits in the Carolina slate belt of central North Carolina constitute a submarine caldera complex, mildly deformed and metamorphosed to lower greenschist facies. The intracaldera facies, including mudflow breccias, ashfall tuffs, pyroclastic flows and lava flows, are 1.2 to 1.8 km thick in the Denton area. The FSM thins abruptly near Badin, passing laterally into extracaldera facies less than 150 m thick of coarse- to fine-grained crystal-rich ashfall tuffs with an upper unit of extremely fine-grained devitrified vitric tuffs. The thickness and average grainsize decrease to the south and east, until the FSM merges with adjacent mudstones. The Morrow Mountain Rhyolite includes bodies of homogeneous rhyolite as much as several km across emplaced within the FSM and stratigraphically lower units, interpreted to be shallow intrusions and some surface-breaking lava domes, emplaced at depths from 0 to 3 km within the caldera and along the ring-fractures. The FSM has been mapped over an area of about 2,400 km[sup 2], and it forms a time-constant layer useful in elucidating slate belt stratigraphy.

  10. Facies comparison of autochthonous and allochthonous Permian and Triassic units, north-central Brooks Range, Alaska

    SciTech Connect

    Adams, K.E.

    1985-04-01

    Eight stratigraphic sections of Permian and Triassic rocks have been studied over a 30 km by 150 km area in the Endicott and Philip Smith Mountains of the central Brooks Range. Six of the sections are located on the Endicott Mountains allochthon, and the remaining two are parautochthonous columns in the Mount Doonerak area. The sections record a facies transition between the autochthonous Sadlerochit Group and Shublik Formation of the northeastern Brooks Range and the characteristically siliceous rocks of the allochthonous Siksikpuk and Otuk formations of the western Brooks Range. Laterally continuous and bioturbated beds of fine-grained sandstone, siltstone, and shale dominantly compose the Permian sequence, whereas the Triassic rocks consist of black shales, thin rhythmically bedded siliceous mudstones, and fossiliferous limestones. When the allochthonous sections are restored to a position south of the Mount Doonerak area, a general shallowing trend from southwest to northwest becomes evident within the reconstructed marine basin. To the south and west, the Permian sediments show a marked increase in silica content, with the occurrence of barite and a corresponding decrease in the thickness of the basal, coarser grained clastics. The Triassic formations also document an increase in silica and the presence of barite to the south and west, while becoming significantly sooty and phosphatic to the north and east. Ongoing petrographic and micropaleontologic studies of the field data will clarify these general paleogeographic relationships.

  11. Geologic landform analysis in the central Piedmont of Virginia and North Carolina, 1

    NASA Technical Reports Server (NTRS)

    Glover, L., III (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. ERTS-1 imagery in the central Piedmont of Va. and N.C. reveals some geologic structures in the Precambrian and Paleozoic metamorphic terrain as well as structure in the younger Triassic deposits. A major synform five miles wide and more than 20 miles long has been identified in the metamorphic rocks north of Danville, Va. Structures in the metavolcanic Carolina slate belt are also identifiable near the confluence of the Dan and Staunton Rivers. Cleared land and other cultural features tend to coincide with topographic reflection of geologic units, thus enhancing the ERTS-1 resolution of some geologic structures. In other cases pseudostructures may be identified when regular geometric configurations of culture bear little or no relation to underlying geologic units. Interpreting geologic structure in the nearly flat and deeply weather Piedmont is a severe test of ERTS-1 imagery resolution. Doubling the resolution and providing stereoscopic overlap would increase the geologic usefulness of these photographs many fold.

  12. Radiological health assessment of natural radioactivity in the vicinity of Obajana cement factory, North Central Nigeria

    PubMed Central

    Isinkaye, Omoniyi Matthew; Jibiri, Nnamdi N.; Olomide, Adebowale A.

    2015-01-01

    Measurements of activity concentrations of natural radionuclides in and around Obajana cement factory, North Central Nigeria have been carried out in this study to determine the activity levels of natural radionuclides in different environmental matrices in order to assess the radiological health hazards associated with the use of these matrices by the local population. A low-background Pb-shielded gamma spectroscopic counting assembly utilizing NaI (Tl) detector was employed for the measurements. The results show that sediment samples have the highest activity concentrations of all the radionuclides relative to soil, farmland soil, and rock samples. The radium equivalent activity and indoor gamma dose rates together with the corresponding annual effective indoor doses evaluated were found to be lower than their permissible limits. It suffices to say, that contrary to age-long fear of radiation risks to the population in the vicinity of the cement factory, no excessive radiological health hazards either indoors and/or outdoors is envisaged. Therefore, the environmental matrices around the factory could be used without any restrictions. PMID:26150688

  13. Association of sea turtles with petroleum platforms in the north-central Gulf of Mexico

    SciTech Connect

    Lohoefener, R.; Hoggard, W.; Mullin, K.; Roden, C.; Rogers, C.

    1990-06-01

    There are over 4,500 petroleum platforms in the north-central Gulf of Mexico. Explosives are commonly used to remove platforms and have the potential to kill nearby sea turtles. From June 1988-June 1990, the authors used aerial surveys to study turtle density and the spatial relationship between turtles and platforms offshore of Louisiana. They sighted 316 turtles most of which (92%) were loggerheads. Seventy-eight percent were sighted just east of the Mississippi River offshore of the Chandeleur Islands. East of the river, turtle densities ranged from 0.92 (winter) to 4.83 turtles/100 sq km (spring). West of the river, annual densities ranged from 0.11-0.50 turtles/100 sq km. East of the river, three statistical tests indicated that turtles were generally closer to platforms than expected by chance alone. West of the river, turtles were randomly located with respect to platform locations. Before explosives are used, current mitigation measures require that no turtle can be sighted within 1,000 m of the platform. East of the river, the probability of a turtle being within 1,000 m of any platform selected at random was about 60%; west of the river, 2-7%. West of the river to about 92 W, the mitigation measures should protect turtles but offshore of the Chandeleur Islands, special precautions should be taken.

  14. Pollen Analysis of Natural Honeys from the Central Region of Shanxi, North China

    PubMed Central

    Song, Xiao-Yan; Yao, Yi-Feng; Yang, Wu-De

    2012-01-01

    Based on qualitative and quantitative melissopalynological analyses, 19 Chinese honeys were classified by botanical origin to determine their floral sources. The honey samples were collected during 2010–2011 from the central region of Shanxi Province, North China. A diverse spectrum of 61 pollen types from 37 families was identified. Fourteen samples were classified as unifloral, whereas the remaining samples were multifloral. Bee-favoured families (occurring in more than 50% of the samples) included Caprifoliaceae (found in 10 samples), Laminaceae (10), Brassicaceae (12), Rosaceae (12), Moraceae (13), Rhamnaceae (15), Asteraceae (17), and Fabaceae (19). In the unifloral honeys, the predominant pollen types were Ziziphus jujuba (in 5 samples), Robinia pseudoacacia (3), Vitex negundo var. heterophylla (2), Sophora japonica (1), Ailanthus altissima (1), Asteraceae type (1), and Fabaceae type (1). The absolute pollen count (i.e., the number of pollen grains per 10 g honey sample) suggested that 13 samples belonged to Group I (<20,000 pollen grains), 4 to Group II (20,000–100,000), and 2 to Group III (100,000–500,000). The dominance of unifloral honeys without toxic pollen grains and the low value of the HDE/P ratio (i.e., honey dew elements/pollen grains from nectariferous plants) indicated that the honey samples are of good quality and suitable for human consumption. PMID:23185358

  15. Remote sensing of regional pyroclastic deposits on the north central portion of the lunar nearside

    NASA Technical Reports Server (NTRS)

    Hawke, B. R.; Campbell, B. A.; Lucey, P. G.; Peterson, C. A.; Coombs, C. R.

    1991-01-01

    High-resolution 3.0-cm radar data for the Rima Bode regional pyroclastic deposit and a number of UV-visible reflectance spectra for regional pyroclastic deposits on the north-central portion of the lunar nearside are analyzed and compared to existing data. The data obtained indicate that small craters in this deposit excavated loose unwelded pyroclastic particles, suggesting that welded layers or lenses do not exist at depths within the deposit's core area. The 70-cm radar data indicate that the Roma Bode deposit is thinner than the pyroclastic unit on the Aristarchus Plateau. The surfaces of all these regional pyroclastic deposits are dominated by ilmenite-rich black spheres, and contamination by low-Ti, nonpyroclastic debris appears to be minimal. The fine-grained block-free uncontaminated Rima Bode would be ideal for lunar mining operations and for rapidly covering lunar base modules with an adequate thickness of shielding material for protection from meteorite impact and space radiation.

  16. Vertical distribution of rocky subtidal assemblages along the exposed coast of north-central Chile

    NASA Astrophysics Data System (ADS)

    Stotz, Wolfgang B.; Aburto, Jaime; Caillaux, Luis M.; González, Sergio A.

    2016-01-01

    Through a systematic study of a stretch of coast in north central Chile, the variety and vertical zonation patterns of the rocky subtidal communities are described, thereby revising apparent uniformity and lack of vertical zonation of the rocky subtidal of southeastern Pacific shores previously reported in the literature. Over the 600 km of coast studied, the following pattern of depth-zonation is described: an upper fringe (lower part of the sublittoral fringe) characterized by barren grounds dominated by calcareous encrusting algae and the sea urchin Tetrapygus niger; an intermediate fringe (upper Infralittoral sub-zone) characterized either by deep barren grounds similar to the former, or kelp beds of Lessonia trabeculata, or an assemblage of suspension feeding organisms, as the big barnacle Austromegabalanus psittacus and/or the tunicate Pyura chilensis; and a deep fringe (Circalittoral sub-zone) dominated by small encrusting or mobile invertebrates. This basic vertical zonation pattern of the shallow rocky subtidal communities seems to be common to most of the temperate coasts of the world. The analysis, first of the occurrence of the general zonation pattern and second of the species composition within the assemblages corresponding to each sub-zone, offers a useful framework for the assessment of the eventual impacts and changes within the shallow rocky subtidal habitat, for example within environmental monitoring programs.

  17. Styles of trap development in Caddo limestone in Bend Arch area, north-central Texas

    SciTech Connect

    Crabtree, J.L. )

    1987-02-01

    The Lower Pennsylvanian Caddo limestone has been a prolific hydrocarbon producer in the Bend arch area of north-central Texas since the early 1900s and continues to be a major exploration target although it is in a mature province. Early explorationists understood the Caddo's large potential when the James pool was discovered in Young County in 1917. Initial flows were greater than 1,000 BOPD in some wells, and field development with additional infill drilling and waterfloods continued into the early 1980s. James pool has produced more than 2 million bbl of oil as of December 1985. Fields in jack, Throckmorton, and Archer Counties had recorded similar successes by the 1940s. The early caddo discoveries were made before singlefold seismic mapping was available, and were based on sparse subsurface control. By the 1950s and 1960s, seismic and subsurface data were more commonly used in the hunt for Caddo reservoirs. Most exploration concepts held that all Caddo traps were structural. Recent studies showed that structural, stratigraphic, and combination traps are common in the Caddo. This study presents examples of each trap type in the Bend arch area, where 49 million bbl of oil has been discovered in the Caddo, and focuses on the current exploration methods.

  18. Priorities for ecological research on energy crops in the north central states

    SciTech Connect

    Ugoretz, S.M.; Rineer, K.C.; Downing, M.

    1995-07-26

    Following the principles set by the National Biofuels Roundtable, a workshop was held in March 1995 which brought together a group of stakeholders and experts in the field of biomass energy and ecology. The mission of the workshop was to identify and set priorities for ecological research to ensure that large-scale biomass energy development in the North Central states occurs in an ecologically sound, sustainable manner. The workshop found that questions about the landscape-scale deployment of biomass plantations were most pressing. The workshop recommended that adaptive resource management principles be applied in a phased development of increasingly larger plantations. Each phase of development would help to answer questions about landscape-scale development; improving the design of subsequent phases. Principles of sustainable agriculture should also be applied to biomass plantations to minimize impact on soils and water quality, maintain productivity and benefit the rural economy. Results of the workshop will be helpful to natural resource and research agencies, as well as utilities and biomass energy developers.

  19. Enhanced Sidescan-Sonar Imagery, North-Central Long Island Sound

    USGS Publications Warehouse

    McMullen, K.Y.; Poppe, L.J.; Schattgen, P.T.; Doran, E.F.

    2008-01-01

    The U.S. Geological Survey, National Oceanic and Atmospheric Administration (NOAA), and Connecticut Department of Environmental Protection have been working cooperatively to map the sea-floor geology within Long Island Sound. Sidescan-sonar imagery collected during three NOAA hydrographic surveys (H11043, H11044, and H11045) was used to interpret the surficial-sediment distribution and sedimentary environments within the Sound. The original sidescan-sonar imagery generated by NOAA was used to evaluate hazards to navigation, which does not require consistent tonal matching throughout the survey. In order to fully utilize these data for geologic interpretation, artifacts within the imagery, primarily due to sidescan-system settings (for example, gain changes), processing techniques (for example, lack of across-track normalization) and environmental noise (for example, sea state), need to be minimized. Sidescan-sonar imagery from surveys H11043, H11044, and H11045 in north-central Long Island Sound was enhanced by matching the grayscale tones between adjacent sidescan-sonar lines to decrease the patchwork effect caused by numerous artifacts and to provide a more coherent sidescan-sonar image for use in geologic interpretation.

  20. Isostatic geoid anomalies over mid-plate swells in the Central North Atlantic

    NASA Astrophysics Data System (ADS)

    Grevemeyer, Ingo

    1999-08-01

    The relation of geoid height data from Geosat/ERM altimeter measurements to seafloor topography from recent shipborne data is investigated for eight igneous provinces located in the Central North Atlantic. The long wavelength undulations of the geoid, reflecting deep-seated density anomalies, were removed by subtracting a low degree and order spherical harmonic representation of the geoid. After converting residual geoid heights and topography to anomalies related to the thermal plate model, both maps were low-pass filtered to isolate the signal associated with local compensation from surface loading. Finally, the ratio of geoid height to topography was determined by fitting a straight line to the data. Cape Verde, Bermuda, Canary and Madeira swells exhibit high geoid/topography ratios, which signify reheating of the lower lithosphere. These features were classified as thermal swells. Geoid/topography ratios occurring over the New England, Corner, Azores and Great Meteor seamount chains can be explained by Airy compensation model of crustal thickening. This requires non-hotspot processes to be active within the Azores and Great Meteor seamounts.

  1. The subsidence evolution of the Fort Worth Basin in north central Texas, U.S.A

    NASA Astrophysics Data System (ADS)

    Al Salem, Ohood Bader

    Although the Fort Worth Basin in north--central Texas has become a major shale--gas production system in recent years, its subsidence history and dynamic relationship to the Ouachita fold--and--thrust belt have not been well understood. Here I study the sedimentation patterns ' model the basin subsidence and thermal maturation histories to understand the evolution of the Fort Worth Basin . Depositional patterns show that the tectonic loading of both the Muenster Arch and the Ouachita fold--and--thrust belt influenced the subsidence of the basin as early as the middle--late Mississippian. Rapid subsidence of the basin initiated in the earliest Pennsylvanian in response to the propagation of the Ouachita fold--and--thrust belt. The rapid subsidence lasted into the Permian based on 2D flexure subsidence and thermal maturation modeling. The Pennsylvanian source rocks in the northeast part of the basin entered the gas maturation window with ˜ 7 km of burial during the late Pennsylvanian--Permian .

  2. Air quality in the 21st century: community outreach in North Central Texas.

    PubMed

    Stuckey, H Troy; Sattler, Melanie L

    2003-06-01

    Public education campaigns, to be successful, must repeat simple, consistent messages over time, using various sources and media. During the 2000, 2001, and 2002 ozone seasons, the North Central Texas Council of Governments (NCTCOG) employed a four-pronged, multimedia approach to educate the public about air quality in the Dallas/Fort Worth (DFW) region. The four-pronged approach included several varied information sources:The new Air Pollution Watch/Warning system based on public health and designed using standard meteorological terminology with notices delivered via e-mail, over the radio, during TV weather forecasts, and on electronic road signs.A revamped Web page, including information about current air quality, ozone exceedances, clean air public meetings, and how to "Do Your Share for Cleaner Air".A PowerPoint presentation used to explain the basics of ozone air pollution, the new Air Pollution Watch/Warning system, and the new Dallas/Fort Worth Clean Air Plan to a variety of constituencies, including the media, scientific/technical/academic groups, elected officials, and community/civic organizations. Newsletter updates, published in the Environmental Resources Department's InsidER (with a circulation of around 1500), to educate and keep the public up-to-date about various air quality issues. This paper provides details about the four-pronged approach, and how it incorporates principles of successful public education campaigns. PMID:12676223

  3. Drinking water and pregnancy outcome in central North Carolina: source, amount, and trihalomethane levels.

    PubMed

    Savitz, D A; Andrews, K W; Pastore, L M

    1995-06-01

    In spite of the recognition of potentially toxic chemicals in chlorinated drinking water, few studies have evaluated reproductive health consequences of such exposure. Using data from a case-control study of miscarriage, preterm delivery, and low birth weight in central North Carolina, we evaluated risk associated with water source, amount, and trihalomethane (THM) concentration. Water source was not related to any of those pregnancy outcomes, but an increasing amount of ingested water was associated with decreased risks of all three outcomes (odds ratios around 1.5 for 0 glasses per day relative to 1-3 glasses per day, falling to 0.8 for 4+ glasses per day). THM concentration and dose (concentration x amount) were not related to pregnancy outcome, with the possible exception of an increased risk of miscarriage in the highest sextile of THM concentration (adjusted odds ratio = 2.8, 95% confidence interval = 1.1-2.7), which was not part of an overall dose-response gradient. These data do not indicate a strong association between chlorination by-products and adverse pregnancy outcome, but given the limited quality of our exposure assessment and the increased miscarriage risk in the highest exposure group, more refined evaluation is warranted. PMID:7556013

  4. Depositional styles from Miocene through Pleistocene in the North Central Gulf of Mexico: An historical reconstruction

    SciTech Connect

    Hunt, J.L. Jr.; Burgess, G.

    1995-10-01

    During the past two years, Minerals Management Service, U.S. Department of the Interior, has classified the reservoir sands from the approximately 1,100 fields across the entire Northern Gulf of Mexico into groups of genetically related plays defined by production, chronostratigraphy, lithostratigraphy, and structure. This study was undertaken in part for the 1995 National Gas and Oil Assessment. Each field was assigned a structural code, and each producible sand was classified by depositional environment. Correlation of the composite type logs with biostratigraphic and seismic data established twelve chronozones from lower Miocene to upper Pleistocene. Sands within each chronozone were classified as transgressive, aggradational, progradational, or deep-sea fan facies. Proved reserves plays, hydrocarbon extents, as well as facies sand limits were mapped for each chronozone. Dramatic changes in depositional styles from the Miocene through the Pliocene are observed in the north-central Gulf of Mexico as the ancestral Mississippi River delta moved both basinward and eastward across offshore Louisiana. The depocenter moved back to the west and significantly basinward during the Pleistocene. Depositional patterns were strongly influenced by localized salt structure and major growth faulting. Salt ridges on the paleo-slope had a damming effect on deposition. When the ridges were breached, the focused sediment supply created areas of slope fan deposits. The results of this study are useful hydrocarbon exploration and development tools.

  5. Thrust belt geometry in the central Carolina slate belt North Carolina

    SciTech Connect

    Huntsman, J.R.; Dockal, J.A.

    1985-01-01

    Newly recognized eastward-directed thrust faults and associated folds and cleavage constitute a major structural element in the central Carolina slate belt near Albemarle, North Carolina. At least two northwest-trending imbricate thrusts occur in a 10 km wide zone that trends 30 km along a northeast strike. Reconnaissance mapping suggests the presence of faults with similar style towards the west of this zone. Rocks directly involved in the thrust include the deep water rhythmites of the Tillery Formation that act as surface of detachment, and, also, a mafic rock that previously was mapped as a gabbro sill. Other field evidence documenting the thrusts includes: drag folds with a pronounced axial planar cleavage that parallels the faults; ramp areas with characteristic rootless folds; dragging of an earlier cleavage into fault surfaces; shear zones and kink bands with the same sense of movement as the thrusts. Axial planar cleavage results in part from pressure solution. The intensity of cleavage and the relative overall strain of the rocks increases from west to east across the thrust zone and suggests that thrusting progressed by successive propogation of footwall faults. Systematic and regular changes in the ratio of Bouma sequence intervals ((A+B+C+D)/E) show a marked discontinuity at the faults and suggest relative horizontal displacements of up to 14 km. Reconnaissance work suggests that the thrust may pre-date but are not younger than the regional low grade metamorphism.

  6. Selenium and mercury in pelagic fish in the central north pacific near Hawaii.

    PubMed

    Kaneko, J John; Ralston, Nicholas V C

    2007-12-01

    Protective effects of selenium against mercury toxicity have been demonstrated in all animal models evaluated. As interactions between selenium and mercury and their molar ratios in seafood are essential factors in evaluating risks associated with dietary mercury exposure, considering mercury content alone is inadequate. In this study, the absolute and molar concentrations of mercury and selenium were determined in edible portions from 420 individual fish representing 15 species of pelagic fish collected from the central North Pacific Ocean near Hawaii. Selenium was in molar excess of mercury in almost all fish species evaluated. The rank order of mean Se/Hg molar ratios was striped marlin (17.6) > yellowfin tuna (14.1) > mahimahi (13.1) > skipjack tuna (12.8) > spearfish (11.4) > wahoo (10.8) > sickle pomfret (6.7) > albacore tuna (5.3) > bigeye tuna (5.2) > blue marlin (4.1) > escolar (2.4) > opah (2.3) > thresher shark (1.5) > swordfish (1.2) > mako shark (0.5). With a Se/Hg molar ratio of less than 1, mako shark was the only fish containing a net molar excess of mercury. A selenium health benefit value based on the absolute amounts and relative proportions of selenium and mercury in seafood is proposed as a more comprehensive seafood safety criterion. PMID:17916947

  7. Azimuthal anisotropy beneath north central Africa from shear wave splitting analyses

    NASA Astrophysics Data System (ADS)

    Lemnifi, Awad A.; Liu, Kelly H.; Gao, Stephen S.; Reed, Cory A.; Elsheikh, Ahmed A.; Yu, Youqiang; Elmelade, Abdala A.

    2015-04-01

    This study represents the first multistation investigation of azimuthal anisotropy beneath the interior of north central Africa, including Libya and adjacent regions, using shear wave splitting (SWS) analysis. Data used in the study include recently available broadband seismic data obtained from 15 stations managed by the Libyan Center for Remote Sensing and Space Science, and those from five other stations at which data are publicly accessible. A total of 583 pairs of high-quality SWS measurements utilizing the PKS, SKKS, and SKS phases demonstrate primarily N-S fast orientations with an average splitting delay time of approximately 1.2 s. An absence of periodic azimuthal variation of the observed splitting parameters indicates the presence of simple anisotropy, and lack of correlation between surficial features and the splitting parameters suggests that the origin of the observed anisotropy is primarily asthenospheric. This conclusion is enhanced by nonperiodic azimuthal variation of the splitting parameters observed at one of the stations located near the boundary of areas with different anisotropic properties. We interpret the observed anisotropy to be the consequence of northward movement of the African plate relative to the asthenosphere toward the Hellenic and Calabrian subduction zones. Local variance in fast orientations may be attributable to flow deflection by the northern edge of the African continental root. The observations provide critical and previously lacking constraints on mantle dynamic models in the vicinity of the convergent boundary between the African and Eurasian plates.

  8. Pleistocene pollen stratigraphy from borehole 81/34, devil's hole area, central north sea

    NASA Astrophysics Data System (ADS)

    Ekman, Sten R.

    1998-09-01

    Twelve pollen assemblage zones are identified in a 229 m deep borehole (BH 81/34) from the Devil's Hole area in the central North Sea (British sector). The sediment from this borehole is Early to Late Pleistocene in age and the observation of massulae from Azolla filiculoides in sediment with reversed polarity indicates an age younger than the Olduvai geomagnetic event for the entire sequence. The Early Pleistocene sediments were at least partly deposited in the vicinity of a river outlet and can be correlated either with the Eburonian or the Menapian cold stage and with the Bavel interglacial and the Linge glacial within the Bavelian stage in the Dutch stratigraphy. The Middle Pleistocene sequence contains an interval rich in Abies, Picea and Pinus, probably deposited during the end of either Cromerian Complex interglacial IV (Noordbergum) or possibly the Holsteinian. The uppermost 80 m of the core contains high frequencies of pre-Quaternary and deteriorated palynomorphs indicating extensive glacial or glaciofluvially reworked sediment.

  9. Forensically important calliphoridae (diptera) associated with pig carrion in rural north-central Florida

    USGS Publications Warehouse

    Gruner, Susan V.; Slone, D.H.; Capinera, J.L.

    2007-01-01

    A study to determine the relative abundance and seasonality of forensically important blow flies (Diptera: Calliphoridae) in rural north-central Florida was conducted using pig carcasses (Sus scrofa L.) as models for human bodies. Seven species of Calliphoridae were collected: Lucilia coeruleiviridis (=Phoenicia) (Macquart), Cochliomyia macellaria (F.), Chrysomya rufifaces (Macquart), Phormia regina (Meigen), Chrysomya megacephala (F.), and a few specimens of Calliphora livida Hall, and Calliphora vicina Robineau-Desvoidy. Species composition in aerial collections of adult flies, preserved larval collections, and samples of larvae reared to the adult stage were all highly correlated. Relative abundance of the species found was significantly different, with L. coeruleiviridis the most abundant species year-round. The relative abundance of the collected species varied significantly by day of decomposition and by season, with significant interactions between season and day, season and species, and day and species. L. coeruleiviridis, C. macellaria, C. rufifaces, and P. regina were found during the entire year, two C. vicina specimens and 11 C. livida specimens were collected from December to March, whereas C. megacephala was collected only from June through September. ?? 2007 Entomological Society of America.

  10. Predicting Residential Air Exchange Rates from Questionnaires and Meteorology: Model Evaluation in Central North Carolina

    PubMed Central

    2010-01-01

    A critical aspect of air pollution exposure models is the estimation of the air exchange rate (AER) of individual homes, where people spend most of their time. The AER, which is the airflow into and out of a building, is a primary mechanism for entry of outdoor air pollutants and removal of indoor source emissions. The mechanistic Lawrence Berkeley Laboratory (LBL) AER model was linked to a leakage area model to predict AER from questionnaires and meteorology. The LBL model was also extended to include natural ventilation (LBLX). Using literature-reported parameter values, AER predictions from LBL and LBLX models were compared to data from 642 daily AER measurements across 31 detached homes in central North Carolina, with corresponding questionnaires and meteorological observations. Data was collected on seven consecutive days during each of four consecutive seasons. For the individual model-predicted and measured AER, the median absolute difference was 43% (0.17 h−1) and 40% (0.17 h−1) for the LBL and LBLX models, respectively. Additionally, a literature-reported empirical scale factor (SF) AER model was evaluated, which showed a median absolute difference of 50% (0.25 h−1). The capability of the LBL, LBLX, and SF models could help reduce the AER uncertainty in air pollution exposure models used to develop exposure metrics for health studies. PMID:21069949

  11. Morphology and sexual dimorphism of the many-lined skink in north central New Mexico

    SciTech Connect

    Hathcock, Charles D.; Wright, Marjorie Alys; Gonzales, Gilbert J.; Sias, Donald S.

    2015-09-04

    In 2001 and 2002, a study of many-lined skinks (Plestiodon multivirgatus) was conducted by Los Alamos National Laboratory biologists in north-central New Mexico to determine means and ranges for several morphological characters and to test for sexual dimorphism. Over both years, there were 539 new captures of many-lined skinks, which included 131 hatchlings. The earliest hatchling capture was on 19 June and the latest capture was on 31 August. Hatchling captures peaked on 1 August in 2001 and 6 August in 2002. The age class, sex, snout–vent length (SVL), tail length (TL), mass, head length (HL), and head width (HW) were recorded and individuals were released at the point of capture. Our results indicate that the SVL, mass, HL, and HW did not exhibit sexual dimorphism. The sex ratio was skewed toward females in this study. It is not known whether the many-lined skink has sexual determination based on environmental factors, but the data here suggest that more research is needed. From these observations, we supplement the limited existing knowledge on the morphology of this species.

  12. Evaluation of low-temperature geothermal potential in north-central Box Elder County, Utah

    SciTech Connect

    Davis, M.C.; Kolesar, P.T.

    1984-12-01

    The low-temperature geothermal resources of north-central Box Elder County, Utah were assessed. Exploration techniques used included chemical analyses of water from wells and springs, temperature surveys, and temperature-depth measurements in unused wells within the study area. The highest water temperatures (31/sup 0/, 30/sup 0/, and 29/sup 0/C) recorded in this research were located in three separate geographic regions, suggesting that no single warm water occurrence dominates the study area. Total dissolved solid (TDS) concentrations ranged from 294 to 11,590 mg/l. Areas of warm water occurrences generally had TDS values of greater than 1100 mg/l. Reservoir temperatures were estimated using chemical geothermometers. Calculated temperatures ranged between 50/sup 0/ and 100/sup 0/C. Temperature-depth measurements were logged in 16 unused wells. Thermal gradients calculated from the profiles ranged from isothermal to 267/sup 0/C/km. The background gradient for the study area appears to be slightly above the average Basin and Range gradient of 35/sup 0/C/km. The highest gradients were calculated for the area approximately eight kilometers west of Snowville, Utah, which is also an area of warm water. 61 refs., 15 figs., 6 tabs.

  13. Morphology and sexual dimorphism of the many-lined skink in north central New Mexico

    DOE PAGESBeta

    Hathcock, Charles D.; Wright, Marjorie Alys; Gonzales, Gilbert J.; Sias, Donald S.

    2015-09-04

    In 2001 and 2002, a study of many-lined skinks (Plestiodon multivirgatus) was conducted by Los Alamos National Laboratory biologists in north-central New Mexico to determine means and ranges for several morphological characters and to test for sexual dimorphism. Over both years, there were 539 new captures of many-lined skinks, which included 131 hatchlings. The earliest hatchling capture was on 19 June and the latest capture was on 31 August. Hatchling captures peaked on 1 August in 2001 and 6 August in 2002. The age class, sex, snout–vent length (SVL), tail length (TL), mass, head length (HL), and head width (HW)more » were recorded and individuals were released at the point of capture. Our results indicate that the SVL, mass, HL, and HW did not exhibit sexual dimorphism. The sex ratio was skewed toward females in this study. It is not known whether the many-lined skink has sexual determination based on environmental factors, but the data here suggest that more research is needed. From these observations, we supplement the limited existing knowledge on the morphology of this species.« less

  14. Impact of climate variability on runoff in the north-central United States

    USGS Publications Warehouse

    Ryberg, Karen R.; Lin, Wei; Vecchia, Aldo V.

    2014-01-01

    Large changes in runoff in the north-central United States have occurred during the past century, with larger floods and increases in runoff tending to occur from the 1970s to the present. The attribution of these changes is a subject of much interest. Long-term precipitation, temperature, and streamflow records were used to compare changes in precipitation and potential evapotranspiration (PET) to changes in runoff within 25 stream basins. The basins studied were organized into four groups, each one representing basins similar in topography, climate, and historic patterns of runoff. Precipitation, PET, and runoff data were adjusted for near-decadal scale variability to examine longer-term changes. A nonlinear water-balance analysis shows that changes in precipitation and PET explain the majority of multidecadal spatial/temporal variability of runoff and flood magnitudes, with precipitation being the dominant driver. Historical changes in climate and runoff in the region appear to be more consistent with complex transient shifts in seasonal climatic conditions than with gradual climate change. A portion of the unexplained variability likely stems from land-use change.

  15. Life history of the striped newt at a north-central Florida breeding pond

    USGS Publications Warehouse

    Johnson, S.A.

    2002-01-01

    I studied the life history of Striped Newts (Notophthalmus perstriatus) at a breeding pond in north-central Florida. Newts were captured in pitfall traps at a drift-fence as they migrated into and out of the pond basin. During the 2-year study, I recorded 10,290 captures (8,127 individuals) of newts at the drift-fence. Newts were active during each month of the study, but there were four peak activity periods, each of which included immigration and emigration events. Immigration events were almost exclusively comprised of adults, whereas emigration events were comprised of adults and recently transformed larvae. I documented 5,296 recently transformed, immature larvae (efts) and 435 recently transformed mature larvae (paedomorphs) during four distinct periods of emigration. Efts matured in the uplands before returning to the pond to breed. In the uplands, male efts (n = 16) grew 0.0183 mm/day on average, whereas average female (n = 24) growth was 0.0167 mm/day. Immigrating adults of both sexes were significantly smaller than emigrating adults. Emigrating efts were smallest, followed by emigrating paedomorphs, immigrating adults, then emigrating adults. The overall adult sex ratio was 1:1.25 (m:f). Sex ratio of emigrating paedomorphs was highly skewed towards females, with one male for every 4.43 females. Newts tended to move during wetter periods, and captures were significantly correlated with rainfall, but rainfall was a poor predictor of the magnitude of newt movements.

  16. Deleterious Emission Abatement through Structured Energy Use Pattern: A North Central Nigeria Perspective

    NASA Astrophysics Data System (ADS)

    Ajayi-Banji, Ademola; Omotosho, Olayinka; Amori, Anthony; Alao, Damilola; Igbode, Imoisime; Abimbola, Olufemi

    2016-05-01

    Holistic view of household energy consumption based on greenhouse gas emissions in the North Central cities of Nigeria was examined in this study. Scenarios considered were based on income level of energy users (low and high) and energy metering system (i.e. pre-paid and post-paid energy billing systems). Strong direct nexus was observed between energy use and emissions pattern. Energy utilization by post-paid category had higher weekly average value of 35.09 and 41.70 kWh as against 23.18 and 33.38 kWh for low and high income pre-paid consumers respectively. Energy use and greenhouse gas emissions from both classification followed similar trend. Data obtained and analysed in the study show that global warming and acidification potentials could be reduced by 33.94 and 19.95 % for low and high income category consumers when pre-paid meters are in place. Conclusively, energy system users with pre-paid metering system displayed reasonable level of management decisions that reduce energy wastage and consequently environmental negative impacts.

  17. Environmental gradients and identification of wetlands in north-central Florida

    USGS Publications Warehouse

    Davis, M.M.; Sprecher, S.W.; Wakeley, J.S.; Best, G.R.

    1996-01-01

    Vegetation composition, soil morphology, and hydrology were characterized along wetland-to-upland gradients at six forested sites in north-central Florida to compare results of Federal wetland delineation methods with 3–5 yr of hydrologic data. Wetland and non-wetland identifications were supported by hydrology data in eight of nine plant communities. Lack of hydric soil indicators and hydrophytic vegetation in two upland communities (scrub and mixed mesic hardwoods) agreed with a deep water table. Six wetland communities (cypress dome, cypress strand, bayhead, cypress/bayhead, red maple/oak swamp, and cedar swamp) with field indicators of wetland hydrology, hydrophytic vegetation, and hydric soils were inundated or had water tables at or near the ground surface at least 5% of the growing season in most years., Flatwoods communities, however, occurred at intermediate positions on the moisture gradient and could not be consistently identified as wetland or upland communities. Identification of flatwoods as wetlands depended on wetland delineation method and was not usually supported by hydrologic measurements. In the flatwoods community, soil properties and vegetation composition were correlated with the mean and standard deviation of water-table depths, as well as the depth continuously exceeded by the water table at least 5% of the growing season in most years. Various hydrologic parameters need to be considered in addition to the 5% exceedence level currently used in Federal wetland delineation guidance when characterizing wetland conditions in low-gradient areas such as flatwoods.

  18. Morphology and sexual dimorphism of the many-lined skink in north central New Mexico

    SciTech Connect

    Hathcock, Charles D.; Wright, Marjorie Alys; Gonzales, Gilbert J.; Sias, Donald S.

    2015-08-01

    In 2001 and 2002, a study of many-lined skinks (Plestiodon multivirgatus) was conducted by Los Alamos National Laboratory biologists in north-central New Mexico to determine means and ranges for several morphological characters and to test for sexual dimorphism. Over both years, there were 539 new captures of many-lined skinks, which included 131 hatchlings. The earliest hatchling capture was on 19 June and the latest capture was on 31 August. Hatchling captures peaked on 1 August in 2001 and 6 August in 2002. The age class, sex, snout–vent length (SVL), tail length (TL), mass, head length (HL), and head width (HW) were recorded and individuals were released at the point of capture. Our results indicate that the SVL, mass, HL, and HW did not exhibit sexual dimorphism. The sex ratio was skewed toward females in this study. It is not known whether the many-lined skink has sexual determination based on environmental factors, but the data here suggest that more research is needed. From these observations, we supplement the limited existing knowledge on the morphology of this species.

  19. Thermocline mixing and vertical oxygen fluxes in the stratified central North Sea

    NASA Astrophysics Data System (ADS)

    Rovelli, Lorenzo; Dengler, Marcus; Schmidt, Mark; Sommer, Stefan; Linke, Peter; McGinnis, Daniel F.

    2016-03-01

    In recent decades, the central North Sea has been experiencing a general trend of decreasing dissolved oxygen (O2) levels during summer. To understand potential causes driving lower O2, we investigated a 3-day period of summertime turbulence and O2 dynamics in the thermocline and bottom boundary layer (BBL). The study focuses on coupling biogeochemical with physical transport processes to identify key drivers of the O2 and organic carbon turnover within the BBL. Combining our flux observations with an analytical process-oriented approach, we resolve drivers that ultimately contribute to determining the BBL O2 levels. We report substantial turbulent O2 fluxes from the thermocline into the otherwise isolated bottom water attributed to the presence of a baroclinic near-inertial wave. This contribution to the local bottom water O2 and carbon budgets has been largely overlooked and is shown to play a role in promoting high carbon turnover in the bottom water while simultaneously maintaining high O2 concentrations. This process may become suppressed with warming climate and stronger stratification, conditions which could promote migrating algal species that potentially shift the O2 production zone higher up within the thermocline.

  20. Increasing Diversity in Geosciences: Geospatial Initiatives at North Carolina Central University

    NASA Astrophysics Data System (ADS)

    Vlahovic, G.; Malhotra, R.; Renslow, M.; Harris, J.; Barnett, A.

    2006-12-01

    Two new initiatives funded by the NSF-GEO and NSF-HRD directorates have potential to advance the geospatial program at the North Carolina Central University (NCCU). As one of only two Historically Black Colleges and Universities (HBCUs) in the southeast offering Geography as a major, NCCU is establishing a GIS Research, Innovative Teaching, and Service (GRITS) Laboratory and has partnered with American Society for Photogrammetry and Remote Sensing (ASPRS) to offer GIS certification to Geography graduates. This presentation will focus on the role that GRITS and GIS certification will play in attracting students to the geoscience majors, the planned curriculum changes, and the emerging partnership with ASPRS to develop and offer "provisional certification" to NCCU students. In addition, authors would also like to describe plans to promote geospatial education in partnership with other educational institutions. NCCUs high minority enrollment (at the present approximately 90%) and quality and tradition of geoscience program make it an ideal incubator for accreditation and certification activities and possible role model for other HBCUs.

  1. Floods of August 21-24, 2007, in Northwestern and North-Central Ohio

    USGS Publications Warehouse

    Straub, David E.; Ebner, Andrew D.; Astifan, Brian M.

    2009-01-01

    Heavy rains in northwestern and north-central Ohio on August 19-22, 2007, caused severe flooding and widespread damages to residential, public, and commercial structures in the communities of Bluffton, Bucyrus, Carey, Columbus Grove, Crestline, Findlay, Mansfield, Ottawa, and Shelby. On August 27, 2007, the Federal Emergency Management Agency (FEMA) issued a notice of a Presidential declaration of a major disaster affecting Allen, Crawford, Hancock, Hardin, Putnam, Richland, Seneca, and Wyandot Counties as a result of the severe flooding. Rainfall totals for most of the flooded area were 3 to 5 in., with some locations reporting as much as 8 to 10 in. Three National Weather Service (NWS) gages in the area indicated a rainfall recurrence interval of greater than 1,000 years, and two indicated a recurrence interval between 500 and 1,000 years. Total damages are estimated at approximately $290 million, with 8,205 residences registering for financial assistance. The U.S. Geological Survey (USGS) computed flood recurrence intervals for peak streamflows at 22 streamgages and 8 ungaged sites in and around the area of major flooding. The peak streamflows at Sandusky River near Bucyrus streamgage and at seven of the eight ungaged sites had estimated recurrence intervals of greater than 500 years. The USGS located and surveyed 421 high-water marks and plotted high-water profiles for approximately 44.5 miles of streams throughout the nine communities.

  2. North-south palaeohydrological contrasts in the central Mediterranean during the Holocene: tentative synthesis and working hypotheses

    NASA Astrophysics Data System (ADS)

    Magny, M.; Combourieu Nebout, N.; de Beaulieu, J. L.; Bout-Roumazeilles, V.; Colombaroli, D.; Desprat, S.; Francke, A.; Joannin, S.; Peyron, O.; Revel, M.; Sadori, L.; Siani, G.; Sicre, M. A.; Samartin, S.; Simonneau, A.; Tinner, W.; Vannière, B.; Wagner, B.; Zanchetta, G.; Anselmetti, F.; Brugiapaglia, E.; Chapron, E.; Debret, M.; Desmet, M.; Didier, J.; Essallami, L.; Galop, D.; Gilli, A.; Haas, J. N.; Kallel, N.; Millet, L.; Stock, A.; Turon, J. L.; Wirth, S.

    2013-04-01

    On the basis of a multi-proxy approach and a strategy combining lacustrine and marine records along a north-south transect, data collected in the Central Mediterranean within the framework of a collaborative project have led to reconstruction of high-resolution and well-dated palaeohydrological records and to assessment of their spatial and temporal coherency. Contrasting patterns of palaeohydrological changes have been evidenced in the Central Mediterranean: south (north) of around 40° N of latitude, the middle part of the Holocene was characterised by lake-level maxima (minima), during an interval dated to ca. 10 300-4500 cal BP to the south and 9000-4500 cal BP to the north. Available data suggest that these contrasting palaeohydrological patterns operated throughout the Holocene, both on millennial and centennial scales. Regarding precipitation seasonality, maximum humidity in the Central Mediterranean during the middle part of the Holocene was characterised by humid winters and dry summers north of ca. 40° N, and humid winters and summers south of ca. 40° N. This may explain an apparent conflict between palaeoclimatic records depending on the proxies used for reconstruction as well as the synchronous expansion of tree species taxa with contrasting climatic requirements. In addition, south of ca. 40° N, the first millennium of the Holocene was characterised by very dry climatic conditions not only in the Eastern, but also in the Central and the Western Mediterranean zones as reflected by low lake levels and delayed reforestation. These results suggest that, in addition to the influence of the Nile discharge reinforced by the African monsoon, the deposition of Sapropel 1 has been favoured (1) by an increase in winter precipitation in the northern Mediterranean borderlands, and (2) by an increase in winter and summer precipitation in the southern Mediterranean area. The climate reversal following the Holocene climate optimum appears to have been punctuated by

  3. Solar forcing of Holocene droughts in a stalagmite record from West Virginia in east-central North America

    NASA Astrophysics Data System (ADS)

    Springer, Gregory S.; Rowe, Harold D.; Hardt, Ben; Edwards, R. Lawrence; Cheng, Hai

    2008-09-01

    Elevated Sr/Ca ratios and δ 13C values in Holocene-age stalagmite BCC-002 from east-central North America record six centennial-scale droughts during the last five North Atlantic Ocean ice-rafted debris (IRD) episodes, previously ascribed to solar irradiance minima. Spectral and cross-spectral analyses of the multi-decadal resolution Sr/Ca and δ 13C time series yield coherent ~200 and ~500 years periodicities. The former is consistent with the de Vries solar irradiance cycle. Cross-spectral analysis of the Sr/Ca and IRD time series yields coherent periodicities of 715- and 455-years, which are harmonics of the 1,450 +/- 500 year IRD periodicity. These coherencies corroborate strong visual correlations and provide convincing evidence for solar forcing of east-central North American droughts and strengthen the case for solar modulation of mid-continent climates. Moisture transport across North America may have lessened during droughts because of weakened north-south temperature and pressure gradients caused by cooling of the tropical Pacific and Atlantic Oceans.

  4. Solar Forcing of Holocene Droughts in a Stalagmite Record From West Virginia in East- Central North America

    NASA Astrophysics Data System (ADS)

    Springer, G. S.; Rowe, H. D.; Hardt, B.; Edwards, R. L.; Cheng, H.

    2008-12-01

    Elevated Sr/Ca ratios and δ13C values in Holocene-age stalagmite BCC-002 from east-central North America record six centennial-scale droughts during the last five North Atlantic Ocean ice-rafted debris (IRD) episodes, previously ascribed to solar irradiance minima. Spectral and cross-spectral analyses of the multi-decadal resolution Sr/Ca and δ13C time series yield coherent ~200 and ~500 years periodicities. The former is consistent with the de Vries solar irradiance cycle. Cross-spectral analysis of the Sr/Ca and IRD time series yields coherent periodicities of 715- and 455-years, which are harmonics of the 1,450±500 year IRD periodicity. These coherencies corroborate strong visual correlations and provide convincing evidence for solar forcing of east-central North American droughts and strengthen the case for solar modulation of mid-continent climates. Moisture transport across North America may have lessened during droughts because of weakened north-south temperature and pressure gradients caused by cooling of the tropical Pacific and Atlantic Oceans.

  5. Aerosol optical depth over central north Asia based on MODIS-Aqua data

    NASA Astrophysics Data System (ADS)

    Avgousta Foutsi, Athina; Korras Carraca, Marios Bruno; Matsoukas, Christos; Biskos, George

    2016-04-01

    Atmospheric aerosols, both natural and anthropogenic, can affect the regional and global climate through their direct, indirect, and semi-direct effects on the radiative energy budget of the Earth-atmosphere system. To quantify these effects it is important to determine the aerosol load, and an effective way to do that is by measuring the aerosol optical depth (AOD). The central Asia region (mainly the Caspian and Aral sea basins), the arid and semi-arid regions of Western China as well as Siberia are of great interest due to the significant natural sources of mineral aerosols originating from local deserts and biomass burning from wildfires in boreal forests. What is of particular interest in the region is the phenomenal shrinking and desertification of the Aral Sea that drives an intense salt and dust transport from the exposed sea-bed to the surrounding regions with important implications in regional air quality. Anthropogenic particles are also observed due to fossil-fuel combustion occurring mainly at oil refineries in the Caspian Sea basin. Here we investigate the spatial and temporal variability of the AOD at 550 nm over central Asia, Siberia and western China, in the region located between 35° N - 65° N and 45° E - 110° E. For our analysis we use Level-3 daily MODIS - Aqua Dark Target - Deep Blue combined product, from the latest collection (006), available in a 1°×1° resolution (ca. 100 km × 100 km) over the period 2002-2014. Our results indicate a significant spatial variability of the aerosol load over the study region. The highest AODs are observed over the Aral Sea year-round, with extreme values reaching 2.1 during July. In the rest of our study region a clear seasonal cycle with highest AOD values (up to 1.2 over the Taklamakan Desert) during spring and summer is observed. The arid parts of central north Asia are characterized by larger aerosol loads during spring, lower but still high AOD in summer and much lower values in autumn and spring

  6. Decadal oscillation of autumn precipitation in Central Vietnam modulated by the East Pacific-North Pacific (EP-NP) teleconnection

    NASA Astrophysics Data System (ADS)

    Li, R.; Wang, S.-Y.; Gillies, R. R.; Buckley, B. M.; Truong, L. H.; Cho, C.

    2015-02-01

    Autumn precipitation over Central Vietnam is associated with an increase in the occurrence of tropical cyclones that lead to frequent flooding and pose a significant threat to lives and property. The present analyses reveal a pronounced decadal oscillation of autumn precipitation in Central Vietnam within the 8-11 year frequency band that is modulated by the East Pacific-North Pacific (EP-NP) teleconnection. The negative phase of the EP-NP pattern is associated with a positive sea surface temperature (SST) anomaly in the South China Sea (SCS) that induces low-level convergence, enhances convection, and increases precipitation over Central Vietnam and adjacent islands including Hainan (China) and the Philippines. This circulation feature around the SCS is embedded in a large-scale circulation associated with SST anomalies across the Pacific Ocean—i.e., cooling in the Eastern and Central tropical Pacific sandwiched by warming in the North and South Pacific as well as the Western Pacific Ocean. The positive phase of the EP-NP features opposite SST and circulation anomalies, with the result being reduced rainfall in Central Vietnam. This out-of-phase relationship and shared decadal spectral coherence between the EP-NP index and autumn precipitation in Central Vietnam might be useful for future climate predictions and flood management.

  7. Spatiotemporal variability in bigeye tuna ( Thunnus obesus) dive behavior in the central North Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Howell, Evan A.; Hawn, Donald R.; Polovina, Jeffrey J.

    2010-07-01

    Data from 29 pop-up archival transmission (PAT) tags deployed on commercial-size bigeye tuna ( Thunnus obesus) in the central North Pacific Ocean from 4°N to 32°N were analyzed to describe variability in their dive behavior across space and time. During the day, bigeye tuna generally spent time in the 0-50 m and 300-400 m depth ranges, with spatial and temporal variability in the deep mode. At night, bigeye tuna generally inhabited the 0-100 m depth range. Three daily dive types were defined based on the percentage of time tuna spent in specific depth layers during the day. These three types were defined as shallow, intermediate, and deep and represented 24.4%, 18.8%, and 56.8% of the total number of days in the study, respectively. More shallow and intermediate dive-type behavior was found in the first half of the year, and in latitudes from 14°N to 16°N and north of 28°N. A greater amount of deep-dive behavior was found in the regions south of 10°N and between 18°N and 28°N during the third and fourth quarters of the year. Dive-type behavior also varied with oceanographic conditions, with more shallow and intermediate behavior found in colder surface waters. Intermediate and deep-dive types were pooled to reflect the depths where bigeye tuna may have potential interactions with fishing gear. A Generalized Additive Model was used to quantify the effects of time, space, and sea surface temperature on this pooled dive type. Results from the model showed that while latitude and quarter of the year were important parameters, sea surface temperature had the most significant effect on the pooled intermediate and deep-dive behavior. Model predictions indicated that the largest percentage of potential interaction would occur in the fourth quarter in the region from 18°N-20°N, which corresponds to the time and place of the highest bigeye tuna catch rates by the Hawaii-based long-line fishery. These results suggest that a model framework using these three

  8. Living benthic foraminifera of the Hess Rise and Suiko Seamount, central North Pacific

    NASA Astrophysics Data System (ADS)

    Ohkushi, Ken'ichi; Natori, Hiro'o.

    2001-05-01

    Rose-Bengal-stained benthic foraminifera in six pilot-core samples and one multicore sample collected from the Hess Rise and Suiko Seamount in August 1994 were studied in order to understand foraminiferal distributions between two areas divided by an oceanic front in the central North Pacific. Samples from the Hess Rise were collected in depths of 2167-3354 m under the warm, saline Kuroshio Extension, while samples from Suiko Seamount came from depths of 1811-1955 m under the cold, less-saline subarctic current. Sediment-trap results for the year prior to our sediment sampling show that organic matter fluxes were about 2.5 times greater at Suiko Seamount than at the Hess Rise. However, the hydrographic structure between 1800 and 3400 m, based on CTD observations, is almost the same at both sites. Temperature decreases from 2.2 to 1.7°C over the depth range of 1800-3400 m, salinity increases from 34.5 to 34.7, and the dissolved oxygen content gradually increases from 1.5 to 3.0 ml l -1. The faunal populations at the Hess Rise are quite different from those at Suiko Seamount. The abundant species at the Hess Rise are Epistominella exigua, Brizalina pacifica, Fursenkoina cedrosensis and Alabaminella weddellensis. These species characteristically inhabit phytodetrital aggregates deposited on an oligotrophic seafloor. The populations at Suiko Seamount are dominated by Triloculina frigida, Lagenammina cf. arenulata, Reophax subfusiformis, and Reophax scorpiurus. The reason for differences between these populations is unclear. However, the typical phytodetritus-dwelling species E. exigua is dominant at the Hess Rise, which is located in a subtropical area that has a pulsed supply of settling organic matter in the spring. On the other hand, E. exigua is rare at Suiko Seamount, a subarctic site where there are more stable and greater fluxes of organic matter in summer and autumn. Occurrences of this species may be related to the seasonally short supply of organic matter

  9. A Rare Early Pliocene Record of Paleoclimate from North-central Indiana, USA

    NASA Astrophysics Data System (ADS)

    Shunk, A. J.; Driese, S. G.; Farlow, J. O.; Fluegeman, R.

    2007-12-01

    The Early Pliocene is a critical period in Earth history, representing warm Earth conditions immediately prior to the development of extensive northern hemisphere glaciation. It thus may provide the best available analog for predicting the climate changes associated with continued global warming. Unfortunately, there are few interior continental records for the early Pliocene from the eastern half of North America and subsequently very little is known about the conditions characterizing climate of this region. The Early Pliocene (4-5 Ma) Pipe Creek Sinkhole (PCS) includes the sediment fill of a complex karst environment that developed in north-central IN (Lat 40° 27' 16", Long 85° 47' 31"). The PCS contains a well-preserved record of sedimentation that includes lacustrine strata with an abundant and diverse fauna and flora that collectively provides a valuable record of paleoclimate from the late Tertiary. Previous research indicates that the floral types are broadly consistent with late Tertiary habitat reconstructions of the US Great Plains. Micromorphologic and stratigraphic analysis of PCS sediments indicate that there are at least three distinct facies present. The underlying red facies is an oxidized silty-clay package that is not fossiliferous. An immature paleosol with root traces represents the pedogenic modification of the red facies and indicates a change in the environment of deposition. The highly fossiliferous lacustrine facies includes abundant quartz sand grains that are not present in the red facies. Geochemical analysis of PCS pond sediment total organic carbon (TOC) derived from vascular land plants sources (based on samples with C/N ratios >20) have δ13 C (PDB) isotope values ranging from -15‰ to - 26.2‰ and a mean value of -22.4‰. The red facies averages 0.1% TOC and has δ13 C values averaging -20.0‰, whereas the paleosol δ13 C values average -24.2‰. These values suggest the presence of a mixture of C3 and C4 plants in the

  10. Seismicity in Central North Africa at low magnitudes: A first look at the TAM event detected data base

    SciTech Connect

    Harben, P.E.,

    1997-01-01

    Teleseismic observations of seismicity in the central North Africa region show that the region is aseismic. This is true for earthquakes with a body wave magnitude greater than about 4 or so. For earthquakes with body wave magnitudes substantially below about 4, the teleseismic observations of seismicity in the central Sahara are incomplete since smaller earthquakes would probably not be detected and located by the current teleseismic monitoring networks. Only one known open seismic station has been operating in the central Sahara. This is the Tamanrasset (TAM) seismic station in southern Algeria. A simple analysis of data records from this station can be used to determine if the central Sahara is also relatively aseismic at magnitudes substantially below 4. That is the primary purpose of this study.

  11. Accommodation of missing shear strain in the Central Walker Lane, western North America: Constraints from dense GPS measurements

    NASA Astrophysics Data System (ADS)

    Bormann, Jayne M.; Hammond, William C.; Kreemer, Corné; Blewitt, Geoffrey

    2016-04-01

    We present 264 new interseismic GPS velocities from the Mobile Array of GPS for Nevada Transtension (MAGNET) and continuous GPS networks that measure Pacific-North American plate boundary deformation in the Central Walker Lane. Relative to a North America-fixed reference frame, northwestward velocities increase smoothly from ∼4 mm/yr in the Basin and Range province to 12.2 mm/yr in the central Sierra Nevada resulting in a Central Walker Lane deformation budget of ∼8 mm/yr. We use an elastic block model to estimate fault slip and block rotation rates and patterns of deformation from the GPS velocities. Right-lateral shear is distributed throughout the Central Walker Lane with strike-slip rates generally <1.5 mm/yr predicted by the block model, but extension rates are highest near north-striking normal faults found along the Sierra Nevada frontal fault system and in a left-stepping, en-echelon series of asymmetric basins that extend from Walker Lake to Lake Tahoe. Neotectonic studies in the western Central Walker Lane find little evidence of strike-slip or oblique faulting in the asymmetric basins, prompting the suggestion that dextral deformation in this region is accommodated through clockwise block rotations. We test this hypothesis and show that a model relying solely on the combination of clockwise block rotations and normal faulting to accommodate dextral transtensional strain accumulation systematically misfits the GPS data in comparison with our preferred model. This suggests that some component of oblique or partitioned right-lateral fault slip is needed to accommodate shear in the asymmetric basins of the western Central Walker Lane. Present-day clockwise vertical axis rotation rates in the Bodie Hills, Carson Domain, and Mina Deflection are between 1-4°/Myr, lower than published paleomagnetic rotation rates, suggesting that block rotation rates have decreased since the Late to Middle Miocene.

  12. Base of Principal Aquifer for the Elkhorn-Loup Model Area, North-Central Nebraska

    USGS Publications Warehouse

    McGuire, V.L.; Peterson, Sean M.

    2008-01-01

    In Nebraska, the water managers in the Natural Resources Districts and the Nebraska Department of Natural Resources are concerned with the effect of ground-water withdrawal on the availability of surface water and the long-term effects of ground-water withdrawal on ground- and surface-water resources. In north-central Nebraska, in the Elkhorn and Loup River Basins, ground water is used for irrigation, domestic supply, and public supply; surface water is used in this area for irrigation, recreation, and hydropower production. In recognition of these sometimes competing ground- and surface-water uses in the Elkhorn and Loup River Basins, the U.S. Geological Survey, the Lewis and Clark Natural Resources District, the Lower Elkhorn Natural Resources District, the Lower Loup Natural Resources District, the Lower Niobrara Natural Resources District, the Lower Platte North Natural Resources District, the Middle Niobrara Natural Resources District, the Upper Elkhorn Natural Resources District, and the Upper Loup Natural Resources District agreed to cooperatively study water resources in the Elkhorn and Loup River Basins. The goals of the overall study were to construct and calibrate a regional ground-water flow model of the area and to use that flow model as a tool to assess current and future effects of ground-water irrigation on stream base flow and to help develop long-term water-resource management strategies for this area, hereafter referred to as the Elkhorn-Loup model area. The Elkhorn-Loup model area covers approximately 30,800 square miles, and extends from the Niobrara River in the north to the Platte River in the south. The western boundary of the Elkhorn-Loup model area coincides with the western boundary of the Middle Niobrara, Twin Platte, and Upper Loup Natural Resources Districts; the eastern boundary coincides with the approximate location of the western extent of glacial till in eastern Nebraska. The principal aquifer in most of the Elkhorn-Loup model

  13. Origin and evolution of mountainous regions north of Tibet, Central Asia

    NASA Astrophysics Data System (ADS)

    Cunningham, D.; Zhang, J.

    2013-12-01

    The huge deformation field associated with the Indo-Eurasia collision provides an unrivalled opportunity to investigate the origin and evolution of anomalously high topography in an intraplate, continental interior setting. Mountainous regions north of Tibet and south of the Hangay Dome are hyper-arid with internally drained basins and very low erosion rates. Consequently, the tectonic signal is very strongly expressed in the landscape. Directly north of Tibet, the Beishan is an anomalous plateau region whose first-order topography cannot be explained by Tertiary-Quaternary faulting, although second-order topographic culminations within the plateau are due to Quaternary-Recent transpressional fault displacements. The Beishan appears to be a peripheral bulge due to significant underthrusting of the Tarim-Dunhuang Block beneath the northern margin of Tibet. North of the Beishan region, the Eastern Tien Shan and Gobi Altai are essentially a transpressional basin and range province whose origin is due to thrust and oblique-slip thrust reactivation of older basement structures and diffuse sinistral strike-slip faulting. The angular relationship between SHmax and older structural trends is the first-order control on the kinematics of Quaternary faulting in the region and the style of mountain building. Restraining bends, thrust blocks and diverse transpressional fault arrays generate a complex 3D orogenic architecture that differs significantly from a contractional fold and thrust belt. Late Cenozoic uplift of the Gobi Altai, eastern Tien Shan and Altai orogens is due to diffuse transpressional reactivation of a mechanically weak Paleozoic terrane collage sandwiched between more rigid Precambrian basement blocks, representing the ';soft' core of Central Asia. Southeast of Mongolia and northeast of Tibet, the Lang Shan, Yabrai Shan and Helan Shan mountainous regions comprise footwall block uplifts associated with Ordos Basin extension and the left-lateral strike

  14. HSPF Modeling of a Forested Headwater in North-Central Minnesota

    NASA Astrophysics Data System (ADS)

    Hess, J.; Nieber, J. L.; Sebestyen, S. D.

    2015-12-01

    The Hydrologic Simulation Program Fortran (HSPF) model is a conceptual based model, in contrast to the alternative grid-based hydrologic models. In its application, the HSPF model has been applied almost exclusively to watersheds scales larger than HUC 14. We applied the HSPF model to a small forested watershed located at the Marcell experimental forest in north-central Minnesota. The watershed has an area of 9.7 hectares and is one of six experimental watersheds managed by the U.S. Forest Service. These experimental watersheds have been in operation since 1955. While some of the experimental watersheds have experienced environmental disturbance (e.g., clear-cutting), the S2 watershed has been in continuous forested condition for the last century. The S2 watershed is composed of forested upland hillslopes that connect to a raised bog area. The forest is aspen (Populus sp.) and birch (Betula papyrifera) on uplands and spruce (Picea mariana) on a 3.2 ha central bog. The upland soils are composed of a shallow sandy loam overlying clay loam which impedes vertical water movement. Water input to the peatland is either from direct precipitation or from the upland hillslopes. Water flux from the bog is either through ET, groundwater seepage losses, or surface discharge to a stream network. Streamflow is measured at a v-notch weir. Within the watershed two upland hillslopes have been isolated to monitor surface runoff and subsurface flow since the 1980's. The HSPF model was applied to the watershed using precipitation and other meteorological data collected within the watershed or nearby on the Experimental Forest. The model representation of the watershed included one element for the upland hillslope area, and one element for the bog area. Daily flows from water years 1991 to 1995 were used to calibrate the model. An equal period of time was used to validate the model from 1996 to 2000. Nash-Sutcliffe values were very good for both calibration and validation. Calibration

  15. Open-System Alkaline Magmatism in the Caledonides of North-Central Norway

    NASA Astrophysics Data System (ADS)

    Barnes, C. G.; Prestvik, T.; Barnes, M. A.

    2002-12-01

    The Caledonian-age Hortavaer intrusion is exposed on small islands and skerries off the coast of north-central Norway. It was emplaced into a range of host rocks that includes calcitic and dolomitic marble to migmatitic gneiss to quartz-rich meta-arenite. The intrusion is unusual relative to Caledonian plutons on the mainland because of its alkaline nature and its possible circa 460-470 Ma age (based on imprecise Sr and Nd isochrones). The intrusion is broadly zoned, with central diorite and outer syenite. Dike-like bodies of monzonite and syenite are also present and are elongate in a NNE-SSW direction. Each lithologic unit is characterized by evidence for magma mingling, particularly by synplutonic dikes and enclaves. In the syenitic zone, mingled magmas ranged from monzonitic (syenitic) to dioritic. In the diorite zone, mingling was dominated by diorite-in-diorite, but composite diorite-syenite dikes are present. The contact between the syenite and diorite units is marked by an approximately 500-m-wide zone of sheeted diorite/syenite dikes that are mutually intrusive. In addition to magma mingling, the complex shows a variety of types of interaction with screens of its host rocks, which are typically subparallel to foliation in the pluton. Some screens were apparently unreactive with the surrounding magma, whereas others resulted in intense reaction and formation of garnet melasyenite, pyroxene-rich monzodiorite, and rare nepheline-bearing rocks. A trend toward Fe enrichment among the dioritic rocks, the low Mg/(Mg+Fe) and Sr contents of the evolved syenites, and curvilinear composition trends for many elements in the suite suggest fractional crystallization was a major control on magma evolution. However, low epsilon Nd (465 Ma) (-3 to -10), moderate initial 87Sr/86Sr (0.705 to 0.710), and high delta18O (+8.3 to +14.0 %) suggest either a crustal source or intense contamination. The presence of primary calcite with delta13C typical of host carbonate rocks

  16. Salt distribution in the Norwegian-Danish Basin, Central North Sea

    NASA Astrophysics Data System (ADS)

    Sassier, Caroline; Jarsve, Erlend; Heeremans, Michel; Mansour Abdelmalak, Mohamed; Faleide, Jan Inge; Helge Gabrielsen, Roy

    2014-05-01

    Salt tectonics have extensively been studied in most parts of the Central North Sea. However, few studies have been done in the Norwegian side of the Norwegian-Danish Basin. In this contribution, we report a new regional analysis of the salt patterns across the offshore Norwegian-Danish Basin. We have mapped the regional distribution of salt structures in the Norwegian-Danish Basin using both old and recent 2D seismic reflection profiles tied to wells. The salt-thickness map shows three distinct salt structures patterns: (1) NW-SE trending salt walls in the northern part of the basin; the spacing between the walls vary between 7 to 12 km; (2) a dense and irregular distribution of salt diapirs in the southern part of the studied area; (3) an irregular pattern of sparse but big salt diapirs in the eastern part of the basin. This domain is characterized by numerous turtle structures associated with salt diapirs. Reflection seismic cross-sections show that most salt structures only pierce the Triassic sedimentary strata whereas only few salt structures reach the seabed. Rotated fault blocks indicate a gliding vergence towards the South in the eastern part of the basin and towards the SE in the western side of the Norwegian-Danish Basin. No mature or compressive salt structures, except some squeezed salt diapirs, are observed in the topographic lows of the basin. The initiation of salt tectonics started during the early Middle Triassic in the entire basin; salt tectonics reactivations were recorded during the Middle Jurassic, Paleogene, and prior to the Quaternary but are not homogeneous across the basin. Salt movements inferred from our study are in good agreement with previous studies. The trend of salt walls (domain 1) indicates a NE-SW extension which is not compatible with N-S trending pre-salt faults. Instead, the strong Triassic subsidence towards the SW has most likely controlled the formation of the salt walls. The salt was initially thicker in domain 2 that

  17. Cation export by overland flow in a recently burnt forest area in north-central Portugal.

    PubMed

    Machado, A I; Serpa, D; Ferreira, R V; Rodríguez-Blanco, M L; Pinto, R; Nunes, M I; Cerqueira, M A; Keizer, J J

    2015-08-15

    The current fire regime in the Mediterranean Basin constitutes a serious threat to natural ecosystems because it drastically enhances surface runoff and soil erosion in the affected areas. Besides soil particles themselves, soil cations can be lost by fire-enhanced overland flow, increasing the risk of fertility loss of the typically shallow and nutrient poor Mediterranean soils. Although the importance of cations for land-use sustainability is widely recognized, cation losses by post-fire runoff have received little research attention. The present study aimed to address this research gap by assessing total exports of Na(+), K(+), Ca(2+) and Mg(2+) in a recently burnt forest area in north-central Portugal. These exports were compared for two types of planted forest (eucalypt vs. maritime pine plantations), two types of parent materials (schist vs. granite) and for two spatial scales (micro-plot vs. hill slope). The study sites were a eucalypt plantation on granite (BEG), a eucalypt plantation on schist (BES) and a maritime pine plantation on schist (BPS). Overland flow samples were collected during the first six months after the wildfire. Cation losses differed strikingly between the two forest types on schist, being higher at the eucalypt than pine site. This difference was evident at both spatial scales, and probably due to the extensive cover of a needle cast from the scorched pine crowns. The role of parent material in cation export was less straightforward as it varied with spatial scale. Cation losses were higher for the eucalypt plantation on schist than for that on granite at the micro-plot scale, whereas the reverse was observed at the hill slope scale. Finally, cation yields were higher at the micro-plot than slope scale, in agreement with the general notion of scaling-effect in runoff generation. PMID:25897728

  18. Vegetated dune morphodynamics during recent stabilization of the Mu Us dune field, north-central China

    NASA Astrophysics Data System (ADS)

    Xu, Zhiwei; Mason, Joseph A.; Lu, Huayu

    2015-01-01

    The response of dune fields to changing environmental conditions can be better understood by investigating how changing vegetation cover affects dune morphodynamics. Significant increases in vegetation and widespread dune stabilization over the years 2000-2012 are evident in high-resolution satellite imagery of the Mu Us dune field in north-central China, possibly a lagged response to changing wind strength and temperature since the 1970s. These trends provide an opportunity to study how dune morphology changes with increasing vegetation stabilization. Vegetation expansion occurs mainly by expansion of pre-existing patches in interdunes. As vegetation spreads from interdunes onto surrounding dunes, it modifies their shapes in competition with wind-driven sand movement, primarily in three ways: 1) vegetation anchoring horns of barchans transforms them to parabolic dunes; 2) vegetation colonizes stoss faces of barchan and transverse dunes, resulting in lower dune height and an elongated stoss face, with shortening of barchan horns; and 3) on transverse dunes, the lee face is fixed by plants that survive sand burial. Along each of these pathways of stabilization, dune morphology tends to change from more barchanoid to more parabolic forms, but that transformation is not always completed before full stabilization. Artificial stabilization leads to an extreme case of "frozen" barchans or transverse dunes with original shapes preserved by rapid establishment of vegetation. Observations in the Mu Us dune field emphasize the point that vegetation growth and aeolian sand transport not only respond to external factors such as climate but also interact with each other. For example, some barchans lose sand mass during vegetation fixation, and actually migrate faster as they become smaller, and vegetation growth on a barchan's lower stoss face may alter sand transport over the dune in a way that favors more rapid stabilization. Conceptual models were generalized for the

  19. Late Triassic to middle Jurassic history of the north-central High Atlas, Morocco

    SciTech Connect

    Letsch, D.K.

    1988-08-01

    The Lower and Middle Jurassic (Liassic and Dogger) rocks in the north-central High Atlas and on the adjacent Oran Meseta, Morocco, were deposited on the subsiding margin of the Triassic/Jurassic High Atlas Trough. This and the Middle Atlas Trough formed as a result of rifting of the Moroccan and Oran Mesetas from the Saharan craton during initial stages of the opening of the modern Atlantic. The Tethys seaway flooded these troughs in the early Liassic, depositing several thousand meters of limestone and marlstone onto the Dogger. Four major Liassic-lower Dogger stratigraphic units were identified, termed Units 1 through 4, oldest to youngest. Unit 1 consists of intertidal and supratidal skeletal pelletal wackestones, algal boundstones, and claystones located on the Oran Meseta and shelf-margin skeletal pelletal oolitic packstones and grainstones along the High Atlas margin. Unit 2 intertongues with and overlies shelf-margin Unit 1 and consists of slope and basin-floor mudstones, wackestones, and turbidite packstones, cyclically interbedded with marlstones. Unit 2 is punctuated by slumps and debris beds near the margin of the basin. At the top of Unit 2 is a condensed zone overlain by basin-floor Unit 3 marlstones, which are cyclically interbedded with mudstones, wackestones, and turbidite packstones. Both Units 2 and 3 thicken basinward, off the ancient shelf margin. Unit 4 lies within Unit 3 and consists of a displaced block (3 /times/ 30 km) of the upper Liassic shelf margin and associated coarse-grained debris, thickest on the marginward side of the block.

  20. Physical and biogeochemical modulation of ocean acidification in the central North Pacific.

    PubMed

    Dore, John E; Lukas, Roger; Sadler, Daniel W; Church, Matthew J; Karl, David M

    2009-07-28

    Atmospheric carbon dioxide (CO(2)) is increasing at an accelerating rate, primarily due to fossil fuel combustion and land use change. A substantial fraction of anthropogenic CO(2) emissions is absorbed by the oceans, resulting in a reduction of seawater pH. Continued acidification may over time have profound effects on marine biota and biogeochemical cycles. Although the physical and chemical basis for ocean acidification is well understood, there exist few field data of sufficient duration, resolution, and accuracy to document the acidification rate and to elucidate the factors governing its variability. Here we report the results of nearly 20 years of time-series measurements of seawater pH and associated parameters at Station ALOHA in the central North Pacific Ocean near Hawaii. We document a significant long-term decreasing trend of -0.0019 +/- 0.0002 y(-1) in surface pH, which is indistinguishable from the rate of acidification expected from equilibration with the atmosphere. Superimposed upon this trend is a strong seasonal pH cycle driven by temperature, mixing, and net photosynthetic CO(2) assimilation. We also observe substantial interannual variability in surface pH, influenced by climate-induced fluctuations in upper ocean stability. Below the mixed layer, we find that the change in acidification is enhanced within distinct subsurface strata. These zones are influenced by remote water mass formation and intrusion, biological carbon remineralization, or both. We suggest that physical and biogeochemical processes alter the acidification rate with depth and time and must therefore be given due consideration when designing and interpreting ocean pH monitoring efforts and predictive models. PMID:19666624

  1. Regional frequency analysis for mapping drought events in north-central Chile

    NASA Astrophysics Data System (ADS)

    Núñez, J. H.; Verbist, K.; Wallis, J. R.; Schaefer, M. G.; Morales, L.; Cornelis, W. M.

    2011-08-01

    SummaryDroughts are among the most important natural disasters, particularly in the arid and semiarid regions of the world. Proper management of droughts requires knowledge of the expected frequency of specific low magnitude precipitation totals for a variety of durations. Probabilistic approaches have often been used to estimate the average recurrence period of a given drought event. However, probabilistic model fitting by conventional methods, such as product moment or maximum likelihood in areas with low availability of long records often produces highly unreliable estimates. Recognizing the need for adequate estimates of return periods of severe droughts in the arid and semiarid region of Chile, a regional frequency analysis method based on L-moments (RFA-LM) was used for estimating and mapping drought frequency. Some adaptations to the existing procedures for forming homogeneous regions were found necessary. In addition, a new 3-parameter distribution, the Gaucho, which is a special case of the 4-parameter Kappa distribution, was introduced, and the analysis procedure was improved by the developments of two new software tools named L-RAP, to perform the RFA-LM analysis, and L-MAP, to map the resulting drought maps. Eight homogeneous sub-regions were delineated using the Gaucho distribution and used to construct return period maps for drought events with 80% and 40% precipitation of the normal. The study confirms the importance of a sub-regional homogeneity test, and the usefulness of the Gaucho distribution. The RFA-LM showed that droughts with a 40% precipitation of the normal have return periods that range from 4 years at the northern arid boundary of the study area to 22 years at the southern sub-humid boundary. The results demonstrate the need for different thresholds for declaring a drought than those currently in use for drought characterization in north-central Chile.

  2. The hydrology of a drained topographical depression within an agricutlural field in north-central Iowa

    USGS Publications Warehouse

    Roth, Jason L.; Capel, Paul D.

    2012-01-01

    North-central Iowa is an agriculturally intensive area comprising the southeastern portion of the Prairie Pothole Region, a landscape containing a high density of enclosed topographical depressions. Artificial drainage practices have been implemented throughout the area to facilitate agricultural production. Vertical surface drains are utilized to drain the topographical depressions that accumulate water. This study focuses on the hydrology of a drained topographical depression located in a 39.5 ha agricultural field. To assess the hydrology of the drained depression, a water balance was constructed for 11 ponding events during the 2008 growing season. Continuous pond and groundwater level data were obtained with pressure transducers. Flows into the vertical surface drain were calculated based on pond depth. Precipitation inflows and evaporative outflows of the ponds were calculated using climatic data. Groundwater levels were used to assess groundwater/pond interactions. Results of the water balances show distinct differences between the inflows to and outflows from the depression based on antecedent conditions. In wet conditions, groundwater inflow sustained the ponds. The ponds receded only after the groundwater level declined to below the land surface. In drier conditions, groundwater was not a source of water to the depression. During these drier conditions, infiltration comprised 30% of the outflows from the depression during declining pond stages. Over the entire study period, the surface drain, delivering water to the stream, was the largest outflow from the pond, accounting for 97% of the outflow, while evapotranspiration was just 2%. Precipitation onto the pond surface proved to be a minor component, accounting for 4% of the total inflows.

  3. Seasonal methane accumulation and release from a gas emission site in the central North Sea

    NASA Astrophysics Data System (ADS)

    Mau, S.; Gentz, T.; Körber, J.-H.; Torres, M. E.; Römer, M.; Sahling, H.; Wintersteller, P.; Martinez, R.; Schlüter, M.; Helmke, E.

    2015-09-01

    We investigated dissolved methane distributions along a 6 km transect crossing active seep sites at 40 m water depth in the central North Sea. These investigations were done under conditions of thermal stratification in summer (July 2013) and homogenous water column in winter (January 2014). Dissolved methane accumulated below the seasonal thermocline in summer with a median concentration of 390 nM, whereas during winter, methane concentrations were typically much lower (median concentration of 22 nM). High-resolution methane analysis using an underwater mass-spectrometer confirmed our summer results and was used to document prevailing stratification over the tidal cycle. We contrast estimates of methane oxidation rates (from 0.1 to 4.0 nM day-1) using the traditional approach scaled to methane concentrations with microbial turnover time values and suggest that the scaling to concentration may obscure the ecosystem microbial activity when comparing systems with different methane concentrations. Our measured and averaged rate constants (k') were on the order of 0.01 day-1, equivalent to a turnover time of 100 days, even when summer stratification led to enhanced methane concentrations in the bottom water. Consistent with these observations, we could not detect known methanotrophs and pmoA genes in water samples collected during both seasons. Estimated methane fluxes indicate that horizontal transport is the dominant process dispersing the methane plume. During periods of high wind speed (winter), more methane is lost to the atmosphere than oxidized in the water. Microbial oxidation seems of minor importance throughout the year.

  4. Elemental characterization of urban particulates at receptor locations in Abuja, north-central Nigeria

    NASA Astrophysics Data System (ADS)

    Abiye, Olawale Emmanuel; Obioh, Imoh B.; Ezeh, Godwin C.

    2013-12-01

    The rising population and increasing urban infrastructures of Abuja have led to increased pressure on the urban environment. Two decades after putting the city of Abuja to use, there is yet no information on the air quality status of the city. Hence, this study was conducted in order to assess the mass concentration and elemental characterization of airborne particulate matter in Abuja, north-central Nigeria. Sampling of PM2.5: aerodynamic diameter ≤2.5 μm and PM10: aerodynamic diameter ≤10 μm were carried out in five urban sites within the city from April, 2009 to May, 2010. "Gent" stacked filter unit sampler equipped with a double stage filters in series was employed for sample collection. Charged helium (4He+) Particle Induced X-ray Emission technique of 2500 keV particle energy and Genie 2000 software were used for spectra acquisition while elemental characterization was achieved using Gupixwin software in order to determine the concentration of eighteen elements (Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Sn, Ba, Ta and Pb). Mass concentrations range between 7-86 μg m-3 and 22-343 μg m-3 for PM2.5 and PM10 respectively. Crustal elements (Si, Ca, and Fe) were found to be predominant in PM10 than in PM2.5 fraction with very high values. Positive correlation r > 0.90 and r > 0.53 to 0.90 exist between metals (V, Co, Ni, Cd, Zn and Pb). PM2.5/PM10 mass ratios were well within the range specified by WHO for developing urban scenario.

  5. Mercury Accumulation in the Forest Floor of the North Central United States

    NASA Astrophysics Data System (ADS)

    Perry, C. H.; Amacher, M. C.; Cannon, W. F.; Kolka, R. K.; Woodruff, L. G.

    2007-12-01

    Atmospherically-deposited Hg has a strong affinity for soil organic matter. Fluxes of Hg in soil water of upland watersheds are generally small, but Hg stored in soil organic matter may be released when the forest floor is consumed by fire. The contribution of Hg from forest fires relative to other anthropogenic sources is an important unknown. The Forest Service, US Department of Agriculture, Forest Inventory and Analysis (FIA) program collects soil samples from forested areas across the United States as part of its Phase 3 sampling, and annual soils inventories are underway or completed in 45 of the 50 states (Alaska, Hawaii, Mississippi, New Mexico, and Oklahoma have yet to be sampled). Our objective here is to inventory and model the spatial distribution of forest floor Hg for a transect running across the north central United States. The collection of forest floor samples was accomplished as part of the standard FIA Phase 3 Soil Quality Indicator program. Field protocols include the measurement of the thickness of the forest floor and the collection of the entire forest floor found within a sampling frame having a diameter of 30 cm. We removed approximately 0.1 g of the sample for plots in our region of interest, and these were sent for Hg analysis by cold-vapor atomic absorption. Observations of mercury concentrations were joined with the Forest Inventory and Analysis Database to assign basic location information and associated inventory data. Mean plot-level values of Hg storage were tested against ecoprovince, forest type group, latitude, and longitude using analysis of variance and geographically weighted regression. Ecoprovince and forest type group were both significant predictors of mercury storage; conifer species tend to store more mercury than hardwood species. Different forest type groups store different amounts of forest floor Hg and in widely dispersed locations.

  6. Assessing the toxicity and teratogenicity of pond water in north-central Minnesota to amphibians

    USGS Publications Warehouse

    Bridges, C.; Little, E.; Gardiner, D.; Petty, J.; Huckins, J.

    2004-01-01

    Background. Incidence of amphibian deformities have increased in recent years, especially in the northern region of the United States. While many factors have been proposed as being responsible for generating deformities (e.g., contaminants, ultraviolet radiation [UV], parasites), no single cause has been definitively established. Methods. To determine whether waterborne chemicals are responsible for amphibian deformities in ponds in north-central Minnesota, we deployed semipermeable membrane devices (SPMDs) in an impacted and a reference site to accumulate lipophilic contaminants. We then exposed native tadpoles (northern leopard frogs; Rana pipiens) to the SPMD extracts combined with two agricultural pesticides (atrazine, carbaryl) at two levels of UV radiation. Results and Discussion. UV radiation alone caused a slight increase in hatching success and tadpole growth rate. Deformity rate among hatchlings was high following exposure to SPMD extracts from the reference site in the absence of UV, suggesting that chemicals present at this site are broken down by UV to less harmful forms, or become less bioavailable. Conversely, impacted site SPMD extracts caused hatchling deformities only in the presence of UV, suggesting that UV potentiates the teratogenicity of the compounds present there. Impacted site SPMD extracts significantly increased the number of bony triangles among metamorphs, a common deformity observed at this site. The incidence of skin webbings increased significantly with SPMD extracts from both sites as well as with our pesticide control containing atrazine and carbaryl alone. Conclusions. Higher deformity rates among tadpoles reared in the presence of UV radiation and SPMD extracts from sites where deformities are common indicates a chemical compound (or compounds) in the water at this site may be causing the deformities. Recommendations and Outlook. It is important to examine the effects of chemical Stressors in the presence of other natural

  7. Evaluation of water resources in part of north-central Texas

    SciTech Connect

    Baker, B.; Duffin, G.; Flores, R.; Lynch, T.

    1990-01-01

    Water resources within the North-Central Texas Region which lies in the Brazos, Red, Sulphur, Sabine, and Trinity River basins, were evaluated. The geologic formations underlying the study area range in age from Paleozoic to Recent. The principal water-bearing formations are the Antlers, Twin Mountains, and Paluxy Formations of the Trinity Group, and the Woodbine Group, all of Cretaceous age. Extensive cones of depression have developed in the piezometric surface of each of the region's principal aquifers, coinciding with areas of large groundwater withdrawals. During the 13-year period 1976 to 1989, water level declines of 25 ft were common in the aquifers studied. The study identified a number of existing and potential water quality problems. Some of these are naturally occurring and are related to geologic structure. Elevated levels of some chemical constituents suggest contamination related to oil-field activities and other industrial sources. The projected water demands for the study area by the year 2010 total over 1.4 million acre-ft. Existing surface-water reservoirs can supply 1.6 million acre ft of water under 2010 conditions. The amount of groundwater currently pumped exceeds the estimated annual effective recharge to the area's aquifers; a portion of the water pumped is drawn from aquifer storage resulting in water level declines. Even though the study area has sufficient surface water to meet projected needs through 2010, rural areas that depend on a groundwater supply could face shortages before 2010 due to the limited availability of groundwater and the high cost of converting to a surface water supply. 93 refs., 19 figs., 3 tabs.

  8. 21st century projections of snowfall and winter severity across central-eastern North America

    NASA Astrophysics Data System (ADS)

    Notaro, M.; Lorenz, D. J.; Hoving, C.; Schummer, M.

    2014-12-01

    Statistically downscaled climate projections from nine global climate models (GCMs) are used to force a snow accumulation and ablation model (SNOW-17) across the central-eastern North American Landscape Conservation Cooperatives (LCCs) to develop high-resolution projections of snowfall, snow depth, and winter severity index (WSI) by the mid- and late 21st century. Here, we use projections of a cumulative WSI (CWSI) known to influence autumn-winter waterfowl migration to demonstrate the utility of SNOW-17 results. The application of statistically downscaled climate data and a snow model leads to a better representation of lake processes in the Great Lakes Basin, topographic effects in the Appalachian Mountains, and spatial patterns of climatological snowfall, compared to the original GCMs. Annual mean snowfall is simulated to decline across the region, particularly in early winter (December-January), leading to a delay in the mean onset of the snow season. Due to a warming-induced acceleration of snowmelt, the percentage loss in snow depth exceeds that of snowfall. Across the Plains and Prairie Potholes LCC and Upper Midwest and Great Lakes LCC, daily snowfall events are projected to become less common, but more intense. The greatest reductions in the number of days per year with a present snowpack are expected close to the historical position of the -5°C isotherm in DJFM, around 44°N. The CWSI is projected to decline substantially during December-January, leading to increased likelihood of delays in timing and intensity of autumn-winter waterfowl migrations.

  9. Hydrologic influence on methane and carbon dioxide dynamics at two north-central Minnesota lakes

    USGS Publications Warehouse

    Striegl, R.G.; Michmerhuizen, C.M.

    1998-01-01

    Annual emissions of (CH4 + CO2) to the atmosphere were proportional to net hydrologic inputs of C, mostly by groundwater, at two lakes in the Shingobee River watershed in north-central Minnesota. Williams Lake (WL), a closed basin lake near the top of the watershed, had a hydraulic residence time of 2-4 yr and groundwater exchange of about +2 mol dissolved inorganic carbon (DIC) and -0.1 mol dissolved organic carbon (DOC) m-2 lake area yr-1. The Shingobee River flows through Shingobee Lake (SL) that had a hydraulic residence of 0.3-0.4 yr and received net groundwater plus surface-water inputs of +5.3 to +7.3 mol DIC and fewer than +1.3 mol (DOC + particulate organic carbon) m-2 yr-1. Approximately 60-80% of net annual C input to SL was from groundwater. Lake storage of CH4 and CO2 was greatest in late winter, with maximum emissions to the atmosphere immediately following ice melt. The lakes emitted CH4 continuously during open water, having annual losses of -1.6 mol CH4 m-2 yr-1 at WL and -1.9 mol CH4 m-2 yr-1 at SL. Although the WL epilimnion was CO2 depleted throughout summer, net annual CO2 exchange with the atmosphere was near zero because springtime emission offset summertime uptake. CO2 supersaturation resulted in emission of -8.0 mol CO2 m-2 yr-1 at SL.

  10. Comparison of atmospheric mercury speciation and deposition at nine sites across central and eastern North America

    NASA Astrophysics Data System (ADS)

    Engle, Mark A.; Tate, Michael T.; Krabbenhoft, David P.; Schauer, James J.; Kolker, Allan; Shanley, James B.; Bothner, Michael H.

    2010-09-01

    This study presents >5 cumulative years of tropospheric mercury (Hg) speciation measurements, over the period of 2003-2009, for eight sites in the central and eastern United States and one site in coastal Puerto Rico. The purpose of this research was to identify local and regional processes that impact Hg speciation and deposition (wet + dry) across a large swath of North America. Sites sampled were selected to represent both a wide range of mercury exposure and environmental conditions. Seasonal mean concentrations of elemental Hg (1.27 ± 0.31 to 2.94 ± 1.57 ng m-3; ? ± σ), reactive gaseous mercury (RGM; 1.5 ± 1.6 to 63.3 ± 529 pg m-3), and fine particulate Hg (1.2 ± 1.4 to 37.9 ± 492 pg m-3) were greatest at sites impacted by Hg point sources. Diel bin plots of Hgo and RGM suggest control by a variety of local/regional processes including impacts from Hg point sources and boundary layer/free tropospheric interactions as well as from larger-scale processes affecting Hg speciation (i.e., input of the global Hg pool, RGM formed from oxidation of Hgo by photochemical compounds at coastal sites, and elemental Hg depletion during periods of dew formation). Comparison of wet Hg deposition (measured), RGM and fine particulate Hg dry deposition (calculated using a multiple resistance model), and anthropogenic point source emissions varied significantly between sites. Significant correlation between emission sources and dry deposition was observed but was highly dependant upon inclusion of data from two sites with exceptionally high deposition. Findings from this study highlight the importance of environmental setting on atmospheric Hg cycling and deposition rates.

  11. Comparative evolution of Pennsylvanian platform margins in Oklahoma and north-central Texas

    SciTech Connect

    Cleaves, A.W.; Puckette, J.O. )

    1991-08-01

    Pennsylvanian evolution of the Midland basin's eastern shelf and the northern shelves of the Anadarko and Arkoma basins demonstrates a strongly contrasting pattern with regard to the facies composition and stability of the shelf margin. For the Midland basin a carbonate ramp system developed adjacent to the Eastern shelf during the early Desmoinesian but received no coarse-grained clastic sediment until after the central Fort Worth basin was completely filled by Ouachita orogenic debris in the late Desmoinesian. At that time, a distinct north-south hingeline formed between the shelf and incipient Midland basin that allowed for subsequent vertical accretion of a Missourian-age double bank system. Due to the absence of active deltaic depocenters across the southern two-thirds of the shelf, the Missourian shelf margin did not prograde basinward nor did a submarine fan system develop adjacent to this reciprocal bank complex. Later, during the Virgilian, a single shelf-edge bank and submarine fan complex prograded the shelf edge westward. The shelf edges for the Anadarko and Arkoma basins demonstrate a significantly different pattern. Only during the late Desmoinesian (Marmaton Group) did a shelf-edge bank develop in association with shelf-slope reciprocal sedimentation. For the Anadarko basin, widespread submarine fans, fed from a northeasterly cratonic source, are first seen with Red Fork deposition. Post-Tonkawa cyclic sedimentation prograded the shelf edge southward and gave rise to a more carbonate-dominated shelf sequence. In virtually all instances the regressive submarine fan units indicate eustatic lowstands of sea level.

  12. Polycyclic aromatic hydrocarbons (PAHs) in aerosols over the central Himalayas along two south-north transects

    NASA Astrophysics Data System (ADS)

    Chen, Pengfei; Li, Chaoliu; Kang, Shichang; Rupakheti, Maheswar; Panday, Arnico K.; Zhang, Qianggong

    2016-04-01

    Our understanding of the transport of polycyclic aromatic hydrocarbons (PAHs) from the Indo-Gangetic Plains (IGP) to the Himalayas remains limited. Concentrations of PAHs were therefore measured in total suspended particles (TSP) from six sites along two south-north transects across the central Himalayas. Spatially, the annual average TSP and PAH (especially 5- and 6-ring) concentrations were found to decrease noticeably along both transects. The dry deposition fluxes had similar distribution pattern with the ambient PAH levels. Moreover, annual TSP and PAH concentrations exhibited a logarithmic decreasing pattern with increasing elevation especially in the non-monsoon seasons (TSP: y=-57.3lnx+552, R2=0.952; PAHs: y=-26.8lnx+229, R2=0.948). The TSP and PAH concentrations showed a clear seasonal variation, with the minimum concentrations around the mid-monsoon season and the maximum concentrations in winter season at Lumbini and Pokhara. While at other remote sites these pollutants were slightly higher during the non-monsoon season than those in the monsoon season. The diagnostic ratio suggested that atmospheric PAHs from the Nepal sites were mainly associated with emission of biomass, coal burning and petroleum combustion. A similar composition pattern was found between the two sides of the Himalayas, suggesting that the northern side of the Himalayas may be affected by anthropogenic emissions from the IGP due to long-range transportation as well as the unique mountain/valley breeze system which bring pollution from the IGP into Tibet across the high Himalayas.

  13. Tributary-stream infiltration in Marsh Creek Valley, north-central Pennsylvania

    USGS Publications Warehouse

    Williams, John H.

    1991-01-01

    The geohydrology of infiltration from five tributary streams along a 3.6-mile reach of Marsh Creek valley in north-central Pennsylvania was investigated during 1983-85. Marsh Creek valley is underlain by up to 100 feet of stratified drift that overlies Devonian bedrock. The stratified drift is overlain by up to 30 feet of alluvial-fan deposits near the tributary streams. Four of the five tributary streams lose large amounts of water to the stratified-drift aquifer in Marsh Creek valley. Along reaches away from the valley wall, infiltration losses from the streams averaged about 2 cubic feet per second per 1,000 feet of wetted channel length. Estimated hydraulic conductivity of the deposits near these streams ranges from 31 to 100 feet per day and averages 61 feet per day. Silty beds of lower permeability near the streams may significantly affect infiltration. The low permeability of the sediments near the fifth stream, which probably consist largely of fine-grained alluvium and swamp deposits, may account for the lack of infiltration losses along this stream. Tributary-stream infiltration accounted for more than 70 percent of the estimated recharge to the stratified-drift aquifer along the reach investigated during water year 1985, in which annual precipitation was below average. The sources of recharge and their estimated rates were: (1) direct infiltration of precipitation on the valley, 1.7 cubic feet per second; (2) unchanneled runoff and ground-water inflow from the uplands, 2.7 cubic feet per second; and (3) tributary-stream infiltration from Asaph Run, 3.7 cubic feet per second, Straight Run, 3.7 cubic feet per second, Dantz Run, 1.2 cubic feet per second, and Canada Run, 1.9 cubic feet per second. The temporal variation in recharge from tributary-stream infiltration greatly affects drawdowns caused by pumping from the wellfield at the National Fisheries Research and Development Laboratory near Straight Run.

  14. Soil respiration in four different land use systems in north central Alberta, Canada

    NASA Astrophysics Data System (ADS)

    Arevalo, Carmela B. M.; Bhatti, Jagtar S.; Chang, Scott X.; Jassal, Rachhpal S.; Sidders, Derek

    2010-03-01

    This study compares soil respiration and its heterotrophic and autotrophic components in four land use types: agriculture, 2 and 9 year old hybrid poplar plantations, grassland, and a native aspen stand in north central Alberta, Canada, over a period of two growing seasons (2006 and 2007). The differences were examined with respect to substrate quality and quantity, fine root biomass, and nutrient availability, in addition to soil temperature and soil water content. Cumulative soil C loss via soil respiration averaged over the two growing seasons was (in decreasing order) 781, 551, 523, 502, and 428 g C m-2 for native aspen stand, 9 year old hybrid poplar plantation, grassland, agriculture and 2 year old hybrid poplar plantation, respectively. We found that ˜75% of soil respiration in the native aspen stand originated from the top 7.5-10 cm litter-fibric-humus layer. Seasonal heterotrophic and autotrophic respiration among the land uses ranged from 97 to 272 and 333 to 560 g C m-2, respectively, contributing up to 35% and 83% of total soil respiration, respectively. The variability in soil respiration across different land uses was explained mainly by site differences in soil temperature (88-94%). Soil respiration followed a pronounced seasonal trend: increasing during the growing season and converging to a minimum in the fall. Soil respiration under different land uses was influenced by (1) ecosystem C stock, (2) temperature sensitivity (Q10) of organic matter present, and (3) organic matter decomposability as indicated by the natural abundance of δ13C. Heterotrophic respiration was influenced by soil temperature, while autotrophic respiration was influenced by fine root biomass and nutrient (NO3- and P) availability. These results are useful in estimating potential responses of soil respiration and its components to future land management and climate change.

  15. Gender, Sexual Health Seeking Behavior, and HIV/AIDS Among Tarok Women in North-Central Nigeria.

    PubMed

    Orisaremi, Titilayo Cordelia

    2016-06-01

    In this study, which was part of a larger project I undertook in North-central Nigeria, I explored the differences in the sexual health seeking behavior of Tarok women and men and how these differences affect the spread of HIV. With the help of three research assistants, I conducted 16 in-depth interviews and 24 focus group discussions in four Tarok communities in North-central Nigeria. I found certain negative effects of gender inequality on women's sexual health seeking behavior in particular, a situation that has adverse implications for HIV acquisition and transmission. I therefore concluded that addressing the challenges of gender inequality is imperative for a sustained fight against HIV and AIDS in Nigeria. PMID:25365697

  16. Annotated bibliography of the hydrology, geology, and geothermal resources of the Jemez Mountains and vicinity, north-central New Mexico

    USGS Publications Warehouse

    Abeyta, Cynthia G.; Delaney, B.M.

    1986-01-01

    The Jemez Mountains volcanic complex, located in north-central New Mexico at the intersection of the Rio Grande rift and Jemez lineament, is a potential location for geothermal energy exploration. This bibliography lists selected papers pertaining to the geology, hydrology, geochemistry, geothermometry, geophysics, ecology, and geothermal and hydrologic modeling aspects of the Jemez region. The bibliography is composed of 795 citations with annotations and a subject and author index. (USGS)

  17. Aircraft measurement of dicarboxylic acids in the free tropospheric aerosols over the western to central North Pacific

    NASA Astrophysics Data System (ADS)

    Narukawa, M.; Kawamura, K.; Okada, K.; Zaizen, Y.; Makino, Y.

    2003-07-01

    Aircraft observation of aerosols was conducted in February 2000, for spatial and vertical distributions of dicarboxylic acids in the free troposphere over the western to central North Pacific. Oxalic, malonic, adipic and azelaic acids were detected in the aerosol samples as the major species. Concentrations of these diacids decreased exponentially with an increase in altitude. They were higher in the western North Pacific (130°E) and decrease eastward. Local flights conducted over Naha (Okinawa), Iwo-jima and Saipan showed that diacid concentrations decreased from the lower to upper troposphere. In the atmosphere over Saipan, where the air is not strongly affected from polluted East Asia, diacid concentrations were almost below the detection limit. Vertical profiles of diacids over Naha and Iwo-jima would be typical over the western North Pacific during winter, suggesting that diacids were significantly injected to the free troposphere from East Asia. Backward air mass trajectories also suggested that the diacids in the free troposphere over the North Pacific are strongly affected by the outflow from East Asia. Diacids, which were produced by both primary emission and secondary photochemical processes in polluted air of East Asia, could alter the physico-chemical properties of aerosols in the free troposphere over the western North Pacific.

  18. Late Holocene Drought Record From Castor Lake, North-Central Washington State

    NASA Astrophysics Data System (ADS)

    Nelson, D. B.; Abbott, M. B.; Polissar, P. J.; Finney, B.

    2006-12-01

    The effects of recent and historic drought in the North American west provide motivation for understanding the natural variability and underlying causes of these events. We present a 6,000-year lake sediment record of water balance from Washington State in an effort to address these questions. A series of overlapping sediment cores were collected and chronological control was established through a combination of radiocarbon, tephrochronology, and cesium isotope activity. Modern basin morphometry and lake water oxygen and hydrogen isotope data indicate closed-basin hydrology and the strong influence of evaporative enrichment on lake water composition, and therefore sensitivity of the system to changes in regional water balance and drought. Samples of endogenic aragonite precipitates were isolated from sediment cores at an average sampling interval of 3.7mm, corresponding to a temporal resolution of approximately 7 years. Grayscale data were generated from digital images of the cores collected under controlled light conditions and are shown to track changes in oxygen isotope values, with darker layers corresponding to periods of increased isotopic composition. In addition to supporting the notion that oxygen isotope data are primarily recording changes in water balance as opposed to changes in water source or temperature, the increased resolution of the grayscale record improves the resolution of the climate signal to the sub-millimeter scale of the laminations. There is a significant correlation between the most recent portion of the Castor Lake grayscale record and a 1,500-yr Palmer Drought Severity Index (PDSI) reconstruction from central Washington (1). The strong association between changes in the Castor Lake record and changes in the PDSI reconstruction provides convincing method validation and strengthens the interpretation of both as drought signals. Spectral analyses of the grayscale record using singular spectrum analysis (SSA), maximum entropy method (MEM

  19. Glacial-eustatic sea-level fluctuation curve for Carboniferous-Permian boundary strata based on outcrops in the North American Midcontinent and North-Central Texas

    SciTech Connect

    Boardman, D.R. . School of Geology)

    1993-02-01

    Based on lithologic and faunal analysis of uppermost Carboniferous through Lower Permian strata (Wabaunsee through lower Chase groups) exposed from southeastern Nebraska through north-central Oklahoma, a preliminary glacial-eustatic sea-level fluctuation curve is presented herein. In addition to the sea-level curve presented for the Midcontinent region, one for coeval outcropping strata (middle and upper Cisco Group) of the Eastern Shelf of the Midland Basin is also presented based on similar criteria. This sea-level curve is derived from new field studies as well as a refinement of earlier curves presented by Harrison (1973), and Boardman and Malinky (1985). The conclusion on the nature of the Carboniferous-Permian boundary strata cyclothems in the Midcontinent is mirrored by the results of that from North-Central Texas. Each of the primary biostratigraphically-based picks for the Carboniferous-Permian boundary coincide with either intermediate of major cycles in both study areas. Utilization of a glacial-eustatic maximum transgressive event for the Carboniferous-Permian boundary should result in a more correlatable level for intercontinental correlation.

  20. Garnet peridotites from Williams kimberlites, north-central Montana, U.S.A

    USGS Publications Warehouse

    Hearn, B.C.; McGee, E.S.

    1983-01-01

    Two Williams kimberlites, 250x350m and 37x390m, in the eastern part of a swarm of 30 middle Eocene alnoitic diatremes in north-central Montana, USA, contain xenoliths of garnet-bearing lherzolites, harzburgites and dunites, in addition to spinel peridotites and upper and lower crustal amphibolites and granulites. Colluvial purple, red, and pink garnets are dominantly Mg- and Cr-rich, indicating their derivation From peridotites or megacrysts, and have CaO and Cr2O3 contents that fall in the lherzolite trend. Temperatures were calculated by the Lindsley-Dixon 20 kb method for lherzolites and by the O'Neill-Wood method for harzburgites and dunites, and pressures were calculated by the MacGregor method, or were assumed to be 50 kb for dunites. Most peridotites equilibrated at 1220-1350?C and 50-60 kb, well above a 44mW/m2 shield geotherm and on or at higher P than the graphite-diamond boundary. Four lherzolites are low T-P (830-990?C, 23-42 kb) and are close to the shield geotherm. All four low T-P lherzolites have coarse textures whereas the high T-P cluster has both coarse and porphyroclastic textures, indicating a range of conditions of deformation and recrystallization in a restricted high T-P range. The tiny size (0.01-0.2 mm) of granulated and euhedral olivines in several xenoliths shows that deformation was occurring just prior to incorporation in kimberlite and that ascent was rapid enough (40-70 km/hr) to retard Further coarsening of fine-grained olivine. For other high T-P peridotites, cessation of deformation and beginning of recrystallization before or during inclusion in kimberlite is suggested by larger (up to 3mm) euhedral olivines in a matrix of fine granulated olivine or by optical continuity of large and nearby small olivines. Two low T-P lherzolites contain distinctive, phlogopite-rimmed, 5-8mm clots of moderate-Cr garnet + Cr-spinel + Cr-diopside + enstatite that are inferred to have formed by reaction of an initial high-Cr garnet brought into the

  1. Prevalence of ectoparasites in a population of feral cats from north central Florida during the summer.

    PubMed

    Akucewich, Lisa H; Philman, Kendra; Clark, Abby; Gillespie, Jeromey; Kunkle, Gail; Nicklin, Constance F; Greiner, Ellis C

    2002-10-16

    Ectoparasites are a common and important cause of skin disorders in cats. Ectoparasites are capable of disease transmission and can cause life-threatening anemia in young or debilitated animals. The objective of this study was to determine the potential feline ectoparasites in domestic cats by using a cohort of feral cats from north central Florida that have not received veterinary care and have no known exposure to insecticide application. A total of 200 feral cats were randomly selected for this study. Four monthly sessions were scheduled for feral cat ectoparasite examination and sample collection. Five minutes flea combing revealed that 185/200 (92.5%) of the cats were infested with fleas. The cat flea, Ctenocephalides felis was the most common flea infesting 92.5% feral cats (mean = 13.6; standard deviation +/- 16.4 fleas per cat). Pulex simulans was identified on 9/200 (4.5%) (mean = 1 +/- 0.50 fleas per cat). Echidnophaga gallinacea was found on 11/200 (5.5%) of cats (mean = 14.8 +/- 9.63 fleas per cat). There was a significant difference (P = 0.0005) in the average number of C. felis counted per cat between months. Mean counts in June (18.3 +/- 2.4) and July (16.6 +/- 2.1) were significantly (P < 0.01) higher than in August (8.4 +/- 2.5) and September (7.7 +/- 2.0). Only 15/200 cats had skin disease. Flea infestation may potentially be the underlying cause in 10/15. Otoscopic examination of both ears revealed mite movement and black ceruminous exudate typically indicative of the presence of Otodectes cynotis in 45/200 (22.5%) cats. Examination of a swab specimen from both ear canals of all cats revealed O. cynotis in 74/200 (37%) cats. Of 74 cats positive on ear swab, 8 (10.8%) showed a normal ear canal appearance (no or mild ceruminous exudate) in both ears upon otoscopic examination. A total of nine ticks were recovered from five cats. The number and species of ticks recovered were: one adult female Rhipicephalus sanguineus; one adult female Amblyomma

  2. Quartz-molybdenite veins in the Priestly Lake granodiorite, north-central Maine

    USGS Publications Warehouse

    Ayuso, Robert A.; Shank, Stephen G.

    1983-01-01

    Quartz-molybdenite veins up to 15 cm in width occur in fine to medium-grained porphyritic biotite-hornblende granodiorite at Priestly Lake north-central Maine. An area of about 150 m x 150 m contains quartz-molybdenite veins; a larger area is characterized by barren quartz veins. Quartz-molybdenite veins are concentrated within the most felsic variants of the intrusion as suggested by lower mafic mineral contents. The pluton has a narrow range in SiO2 (67-70 wt.%), major oxides, and in trace-element compositions. Molybdenite occurs as coarse grained clusters in pockets within the quartz veins, and fills fractures in the quartz veins and host rocks. Disseminated molybdenite in the granodiorite is relatively rare and occurs only in the area characterized by a high density of quartz veins (up to 50 veins per square meter). Alteration envelopes along the quartz veins are very thin or absent, although in some areas the granodiorite appears to be selectively and pervasively altered. Sericite, chlorite, epidote, calcite, pyrite, and quartz are concentrated near the quartz-molybdenite veins. Many of the field and geochemical characteristics of the Priestly Lake pluton are unlike those of major molybdenum-producing areas (Climax, Henderson, Urad). For example, the area of alteration seems to be of limited extent, the host rock is not intensely altered hydrothermally at the surface, the density of fractures is rather low in the mineralized area, and the amount of disseminated molybdenite appears to be small. However, the Priestly Lake pluton may be a small fraction of a concealed batholith as suggested by geophysical data. It is conceivable that the type of mineralization at the surface might be the expression of more extensive molybdenite mineralization at depth. The quartz-molybdenite veins in the Priestly Lake pluton are significant because they indicate that potential molybdenum sources for producing mineralized granites were available at depth. Future studies should be

  3. Chronological refinement of an ice core record at Upper Fremont Glacier in south central North America

    SciTech Connect

    Schuster, Paul F.; White, David E.; Naftz, David L.; Cecil, L. DeWayne

    2000-02-27

    alpine regions of central North America may have occurred on a relatively short (decadal) timescale. (c) 2000 American Geophysical Union.

  4. Late Glacial and Holocene sedimentary evolution of Czechowskie Lake (Eastern Pomerania, North Central Poland)

    NASA Astrophysics Data System (ADS)

    Kordowski, Jarosław; Błaszkiewicz, Mirosław; Kramkowski, Mateusz; Noryśkiewicz, Agnieszka M.; Słowiński, Michał; Tyszkowski, Sebastian; Brauer, Achim; Ott, Florian

    2015-04-01

    Czechowskie Lake is located in north-central Poland in Tuchola Forest, about 100 kilometers SW away from Gdańsk. In the deepest parts of the lake there are preserved laminated sediments with an excellent Holocene climatic record. The lake has the area of 76,6 ha. Actual water level is at 109,9 m a.s.l. The average depth is 9,59 m, maximal 32 m. It occupies a large subglacial channel, reproduced within the glacifluvial sediments of the last glaciation. The lake has a history reaching back to Pommeranian phase which is proved by analysis of sedimentary succesions in the vicinity of present-day waterbody. Primarily it come to existence as an very variable ice dammed lake but after dead ice and permafrost desintegration it changed into a stable lake. In the terrestrialised part oft the lake and in its litoral zone there were curried out numerous boreholes within limnic and slope sediments. They have been analysed in respect to lithology and structure. Some of them were also investigated palynologically which along with radiocarbon datings allowed to reconstruct major phases of the water level fluctuations. The maximum infilling with the limnic and telmatic sediments reaches over 12 m. In the bottom of the lake there is a marked presence of many overdeepenings with the diameter of dozen or several dozen meters and the depth of up to 10 m with numerous, distinct throughs between them. They favoured the preservation of the lamination in the deepest parts of the lake due to waves hampering and stopping of the density circulation in the lake waterbody. The analysis of limnic sediments revealed considerable spatial and temporal variability mainly in dependance of the area of the water body and water level in time of deposition. In the lake are recorded three distinct phases of lake level decrease. The sedimentary evolution in the isolated minor lake basins showed gradual decrease of mineral and organic deposition in favour for carbonate one although in places separated by

  5. Stratigraphy, geochronology, geochemistry and tectonic setting of the Mesozoic Nazas Formation, north-central Mexico

    NASA Astrophysics Data System (ADS)

    Bartolini, Claudio

    Late Triassic to Middle Jurassic volcanic-sedimentary sequences that were part of the Mesozoic continental-margin of western North America are exposed in northern and central Mexico. These sequences have been grouped into the Nazas Formation and crop out in the states of Durango, Coahuila, Zacatecas, and San Luis Potosi. The Nazas Formation consists of 2,500 m or more of volcanic and pyroclastic rocks and interbedded clastic sedimentary rocks that were deposited in alluvial fan and fluvial depositional systems that developed in intra-arc basins, mainly fault-bound grabens and topographic depressions within an extending Mesozoic volcanic arc. Major and trace element geochemistry of volcanic rocks suggests that the volcanic suite is calc-alkaline and includes rhyolite, dacite, rhyodacite, andesite, trachyandesite and rare basalt. Pyroclastic rocks are basically air-fall tuffs and volcanic breccias. The sedimentary strata include conglomerate, sandstone, shale, and siltstone, locally red in color. Geochronology (Ar-Ar, K-Ar and Rb-Sr) and field evidence indicate that the age of the Nazas Formation ranges from Late Triassic to Middle Jurassic, but the peak of arc volcanism appears to be Early and Middle Jurassic. The Mesozoic magmatic arc in Mexico has a northwest trend and extends from Sonora to Chiapas. The arc structure is more than 2,000 km long, and possibly up to 150 km wide. The width of the arc is uncertain due to the limited number of surface outcrops, however, it did not extend east into the Gulf of Mexico. Arc-related magmatism began in latest Triassic time, but the peak of arc evolution occurred during the Early and Middle Jurassic. By Oxfordian time, the arc was deeply dissected and eroded, and magmatic activity had ceased. A marine transgression from the Gulf of Mexico covered most of the Nazas arc, depositing the initial sediments of the Oxfordian Zuloaga Limestone in the Mexican Geosyncline. Jurassic crustal extension in the Gulf of Mexico was

  6. Determinants of HIV-related cardiac disease among adults in north central Nigeria

    PubMed Central

    Isiguzo, Godsent; Okeahialam, Basil; Danbauchi, Solomon; Odili, Augustin; Iroezindu, Michael

    2013-01-01

    Objective The aim of the present study was to evaluate the determinants of HIV-related cardiac disease (HRCD) among adults in north central Nigeria. This was a hospital-based cross-sectional study recruiting patients who were HIV positive attending the HIV clinic at Jos University teaching Hospital, Nigeria. Methods A total of 200 adults who were HIV positive and aged ≥18 years were consecutively recruited. All patients were administered a questionnaire and underwent clinical examination, laboratory investigation for haemoglobin estimation, CD4 cell count, viral load, serum lipid profile, hepatitis B surface antigen, anti-hepatitis C virus antibody, electrocardiogram and two-dimensional echocardiography Doppler studies. The outcome measure was echocardiography-defined cardiac disease, such as systolic dysfunction, diastolic dysfunction, isolated left ventricular dilatation, right ventricular dysfunction or pulmonary hypertension. Results The mean age of the study population was 38±9 years. The majority (71%) were women and were on average younger than the men (36±8 years vs 47±9 years, p<0.0002). Highly active anti-retroviral therapy (HAART) use was seen in 84.4% of subjects. The median CD4 cell count for the study population was 358 cells/µL; the count was 459 (95% CI 321 to 550) cells/µL for subjects without HRCD and 193 (95% CI 126 to 357) cells/µL for subjects with HRCD (p<0.001). HAART-naive subjects with HRCD had a mean CD4 cell count of 121 cells/µL vs 200 cells/µL for those on HAART (p<0.01). CD4 cell count (OR = 0.25, 95% CI 0.15 to 0.45) and duration of diagnosis (OR=3.88, 95% CI 1.20 to 13.71) were the significant determinants of HRCD on multivariate analysis. Conclusions Duration of HIV diagnosis and degree of immunosuppression were the significant determinants of HRCD. There is therefore a need to reduce cardiovascular morbidity in patients infected with HIV through early diagnosis/sustained use of HAART, early screening for HRCD

  7. Soil water dynamic studies from two Arenosols of North-Central Namibia

    NASA Astrophysics Data System (ADS)

    Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus

    2015-04-01

    In North-Central Namibia, farmers mainly cultivate Pearl Millet based on dryland agriculture. Based on interviews of farmers in the study area, agricultural soil quality is mostly related to soil water moisture characteristics, in particular the capacity to provide water during dry periods on one hand and the risk to get water-logged on the other. In order to assess these differences in the perspective of water use efficiency, two soils types have been studied. The first one, Omutunda (mostly Arenosol hypereutric), is nutrient-rich, but does not supply much water to the crops during long rainless periods that occur over the growing season. The other soil studied, Ehenge (mostly hypoluvic albic Arenosol), is nutrient-poor, but it keeps water for a longer period. Soil water monitoring as well as rainfall simulations have been used to examine the difference in soil hydraulics between these two soils. These data have been compared to the information gathered during the interviews on the farmers' perspective on the use of both soils. The nutrient-rich soil, Omutunda, has very high water retention capacity, but a high landscape position, the presence of sealing, as well as low percolation rates can cause high runoff and evaporation. This is particularly obvious during rainstorms that are frequent in the area. On the other hand, high percolation rates into the sandy top layers of the poor-nutrient soil, Ehenge, permit rainwater to reach a deep sandy loam layer in which water is accumulated. Low matric potential of the upper sandy layers isolates this water reservoir from the dry soil surface and crops can use this water to grow for at least six rainless weeks. These results show that, despite their spatial proximity, these two soils types would have very different requirements related to irrigation to balance rainfall regimes. This is particularly important to adapt to future climate change in the area, which should increase rainfall intensity events and lengthen rainless

  8. The Beni-Ilmane (North-Central Algeria) Earthquake Sequence of May 2010

    NASA Astrophysics Data System (ADS)

    Yelles-Chaouche, A. K.; Abacha, I.; Semmane, F.; Beldjoudi, H.; Djellit, H.

    2014-07-01

    Starting on 14 May 2010 and lasting several months, the village of Beni-Ilmane (Msila District, North-Central Algeria) and its surroundings were struck by an important seismic crisis marked by three successive moderate shocks (5.0 ≤ M d ≤ 5.2). This sequence of events caused severe damage in the Beni-Ilmane village and in the epicentral area. The poor quality of masonry construction and the cumulative effects of the large number of aftershock events played a key role in the destruction. To follow this earthquake sequence, 11 temporary seismic stations, in addition to the permanent stations of the Algerian seismic network, were deployed in the region. A representative set of well located aftershocks in the period of maximum activity (lasting 18 days) were selected. The horizontal distribution of the aftershocks shows two main earthquake clusters located near Beni-Ilmane village, one cluster oriented E-W and the other oriented NNE-SSW, crossing the first cluster at its eastern tip. The aftershocks distribution suggests that the three main shocks ruptured two distinct and adjacent fault segments of about 8 km length. The focal mechanisms of the first and third events, located in the NNE-SSW cluster, show near-vertical left-lateral strike-slip fault planes. In the second cluster, oriented E-W, focal mechanisms show a high-angle reverse fault. A field survey, initiated immediately after the first main shock, identified surface fissures generated by the three largest events in the sequence. The fissures, concentrated in a narrow area at the western termination of the NE-SW Jebel Choukchot anticline (location of Beni-Ilmane village), showed several orientations which were mainly related to gravity instabilities. The 2010 Beni-Ilmane earthquake sequence, located in the Bibans-Hodna Mountains transition zone, demonstrates that the Tellian Atlas-High Plateaus border region is an active seismic zone marked by moderate and possibly strong earthquakes; thus, a reevaluation

  9. Mercury in wild mushrooms and underlying soil substrate from Koszalin, North-central Poland.

    PubMed

    Falandysz, Jerzy; Jedrusiak, Aneta; Lipka, Krzysztof; Kannan, Kurunthachalam; Kawano, Masahide; Gucia, Magdalena; Brzostowski, Andrzej; Dadej, Monika

    2004-01-01

    Concentrations of total mercury were determined by cold-vapour atomic absorption spectroscopy (CV-AAS) in 221 caps and 221 stalks of 15 species of wild growing higher fungi/mushrooms and 221 samples of corresponding soil substrate collected in 1997-98 in Manowo County, near the city of Koszalin in North-central Poland. Mean mercury concentrations in caps and stalks of the mushroom species examined and soils varied between 30+/-31 and 920+/-280, 17+/-11 and 560+/-220, and 10+/-9 and 170+/-110 ng/g dry matter, respectively. Cap to stalk mercury concentration quotients were from 1.0+/-0.4 in poison pax (Paxillus involutus) to 2.8+/-0.7 in slippery jack (Suillus luteus). Brown cort (Cortinarius malicorius), fly agaric (Amanita muscaria), orange-brown ringless amanita (A. fulva), red-aspen bolete (Leccinum rufum) and mutagen milk cap (Lactarius necator) contained the highest concentrations of mercury both in caps and stalks, and mean concentrations varied between 600+/-750 and 920+/-280 and 370+/-470 and 560+/-220 ng/g dry matter, respectively. An estimate of daily intake of mercury from mushroom consumption indicated that the flesh of edible species of mushrooms may not pose hazards to human health even at a maximum consumption rate of 28 g/day. However, it should be noted that mercury intake from other foods will augment the daily intake rates. Species such as the sickener (Russula emetica), Geranium-scented russula (R. fellea) and poison pax (P. involutus) did not concentrate mercury as evidenced from the bioconcentration factors (BCFs: concentrations in mushroom/concentration in soil substrate), which were less than 1. Similarly, red-hot milk cap (L. rufus), rickstone funnel cap (Clitocybe geotropa) and European cow bolete (S. bovinus) were observed to be weak accumulators of mercury. Fly agaric (A. muscaria) accumulated great concentrations of mercury with BCFs reaching 73+/-42 and 38+/-22 in caps and stalks, respectively. Mercury BCFs of between 4.0+/-2.3 and 23

  10. Runoff and inter-rill soil erosion following wildfire and terracing in north-central Portugal

    NASA Astrophysics Data System (ADS)

    Martins, Martinho A. S.; Machado, Ana Isabel; Serpa, Dalila; Prats, Sergio; Faria, Silvia; Eufemia Varela, María; Keizer, Jan Jacob

    2013-04-01

    In Portugal, wildfires occur frequently and affect large areas, on average some 100.000 ha per year but in extreme years such as 2003 and 2005 over 300.000 ha. Wildfires can lead to considerable changes in geomorphologic and hydrological processes, as evidenced by the strong and sometimes extreme responses in post-fire runoff and erosion reported from various parts of the world, including Portugal. Besides wildfire itself, also post-fire forestry practices can strongly influence the hydrological and erosion response in recently burnt areas. In north-central Portugal, for example, rip ploughing in down-slope direction was found to be far more damaging in terms of soil loss than fire. Whilst rip ploughing in down-slope direction has now by and large been abandoned in the region, the construction of terraces in preparation of new tree and especially eucalypt plantations has become increasingly common. Although terraces are traditionally viewed as a technique for soil conservation, the authors have measured high splash erosion rates on recent terraces and have frequently observed small-scale erosion features and, on one occasion, gully formation over the full hill slope length. Runoff and sediment losses, however, have hardly ever been quantified for recently terraced plantations. In this study, we compared runoff and erosion, at the micro-plot scale, before and after terracing, during the first seven months after a wildfire and during the subsequent 17 months. This was done at two contrasting hill slopes, designated here as eucalypt and pine site. The former was, at the time of the wildfire, covered by eucalypt and then terraced and re-planted with eucalypt over its full extent; the latter was initially covered with pine and then partially terraced and planted with eucalypt and partially left to regenerate spontaneously. Total rainfall was rather similar for the pre- and post-terracing period (1205 and 1437 mm), in spite of their different, above-mentioned durations

  11. Biofuel production and climate mitigation potential from marginal lands in US North Central region

    NASA Astrophysics Data System (ADS)

    Gelfand, I.; Sahajpal, R.; Zhang, X.; Izaurralde, R. C.; Robertson, G. P.

    2010-12-01

    An ever-increasing demand for liquid fuels, amidst concerns of anthropogenic impacts on the environment and fossil fuels availability, has spurred a strong interest in the development of agriculturally-based renewable energy sources. However, increasing demand for food as well as direct and indirect effects on land use, have raised concerns about reliance on grain-based ethanol and shifted research towards the direction of cellulosic feedstocks. In order to understand the future possibility for using agricultural systems for bio-fuel production, we present here a full greenhouse gas (GHG) balance of six potential sources of cellulosic feedstocks production. From 1991 to 2008, we measured GHGs sinks and sources in cropped and nearby unmanaged ecosystems in SW Michigan. The measurements included soil fluxes of GHGs (N2O and CH4), soil organic carbon concentration change, agronomic practices data, and biomass yields. We analyzed two types of intensively managed annual cropping systems under corn-soybean-wheat rotation (conventional tillage and no till), two perennial systems (alfalfa and poplar plantation), and one successional system. The use of agricultural residues for biofuel feedstock from conventionally-tilled crops had the lowest climate stabilization potential (-9 ±13 gCO2e m-2 y-1). In contrast, biomass collected from a successional system fertilized with N at123 kg ha-1y-1 showed the highest climate stabilization potential (-749 ±30 gCO2e m-2 y-1). We used our results to parameterize the EPIC model, which, together with GIS analysis was used to scale up the biomass productivity of the best environmentally performing systems to the marginal lands of the 10-state U.S. North Central region. Assuming 80 km as the maximum distance for road haulage to the biorefinery from the field, we identified 32 potential biorefinery placements each capable of supplying sufficient feedstock to produce at least 133 × 106 L y-1. In total, ethanol production from marginal

  12. Late-Pleistocene evolution of the East Mediterranean shallow continental shelf of north-central Israel

    NASA Astrophysics Data System (ADS)

    Shtienberg, Gilad; Dix, Justin; Waldmann, Nicolas; Makovsky, Yizhaq; Bookman, Revital; Roskin, Joel; Bialik, Or; Golan, Arik; Sivan, Dorit

    2016-04-01

    Sea-level fluctuations are a dominant and dynamic mechanism that control coastal environmental through time. This is especially the case for the successive regressions and transgressions over the last interglacial cycle, which have shaped the deposition, preservation and erosion patterns of unconsolidated sediments currently submerged on continental shelves. The current study focuses on an integrated high-resolution marine and terrestrial litho-stratigraphic and geophysical framework of the north-central Mediterranean coastal zone of Israel. The interpretation enabled the reconstruction of the coastal evolution over the last ˜130 ka. A multi-disciplinary approach was applied by compiling existing elevation raster grids, bathymetric charts, detailed lithological borehole data-sets, a dense 110 km long sub-bottom geophysical survey and seven continuous boreholes sediment records. Based on seismic stratigraphic analysis, observed geometries, and reflective appearances, six bounding surfaces and seven seismic units were identified and characterized. Meanwhile, the chronostratigraphy of the terrestrial side was constructed through integration of magnetic susceptibility, sedimentological and geochemical analysis with 17 new OSL ages. The seismic units were correlated with the available terrestrial borehole data and then associated to the retrieved terrestrial chronostratigraphy to produce a 4D reconstruction model of the paleo-landscape. The entire unconsolidated sequence overlies a calcareous aeolianite (locally named Kurkar unit) dated from ˜131 - ˜104 ka, which represents the top of the last interglacial cycle dune sediments. The lower unconsolidated unit consists of a red silty loam dated to ˜71 ka. This Red-Paleosol unit is overlaid by a dark brown clayey silty loam This Brown-Paleosol unit dates to ˜58 - ˜36 ka and is overlaid by a dark silty clay wetland deposit dated to ˜21 - ˜10 ka. The wetland unit is topped by a quartz sand dated to ˜6.6 - 0.1 ka

  13. Chronological refinement of an ice core record at Upper Fremont Glacier in south central North America

    USGS Publications Warehouse

    Schuster, P.F.; White, D.E.; Naftz, D.L.; Cecil, L.D.

    2000-01-01

    The potential to use ice cores from alpine glaciers in the midlatitudes to reconstruct paleoclimatic records has not been widely recognized. Although excellent paleoclimatic records exist for the polar regions, paleoclimatic ice core records are not common from midlatitude locations. An ice core removed from the Upper Fremont Glacier in Wyoming provides evidence for abrupt climate change during the mid-1800s. Volcanic events (Krakatau and Tambora) identified from electrical conductivity measurements (ECM) and isotopic and chemical data from the Upper Fremont Glacier were reexamined to confirm and refine previous chronological estimates of the ice core. At a depth of 152 m the refined age-depth profile shows good agreement (1736 ?? 10 A.D.) with the 14C age date (1729 ?? 95 A.D.). The ??18O profile of the Upper Fremont Glacier (UFG) ice core indicates a change in climate known as the Little Ice Age (LIA). However, the sampling interval for ??18O is sufficiently large (20 cm) such that it is difficult to pinpoint the LIA termination on the basis of ??18O data alone. Other research has shown that changes in the ??18O variance are generally coincident with changes in ECM variance. The ECM data set contains over 125,000 data points at a resolution of 1 data point per millimeter of ice core. A 999-point running average of the ECM data set and results from f tests indicates that the variance of the ECM data decreases significantly at about 108 m. At this depth, the age-depth profile predicts an age of 1845 A.D. Results indicate the termination of the LIA was abrupt with a major climatic shift to warmer temperatures around 1845 A.D. and continuing to present day. Prediction limits (error bars) calculated for the profile ages are ??10 years (90% confidence level). Thus a conservative estimate for the time taken to complete the LIA climatic shift to present-day climate is about 10 years, suggesting the LIA termination in alpine regions of central North America may have

  14. Crater palaeolakes in the Tibesti mountains (Central Sahara, North Chad) - New insights into past Saharan climates

    NASA Astrophysics Data System (ADS)

    Kröpelin, Stefan; Dinies, Michèle; Sylvestre, Florence; Hoelzmann, Philipp

    2016-04-01

    cm. Grasses and wormword are dominating throughout the sequence, probably reflecting the main constituents of the regional vegetation. Cattail (Typha/Sparganium) and especially milfoil (Myriophyllum) are recorded abundantly and continuously throughout the sequence. In combination with green algae like Pediastrum the first pollen spectra indicate a lake shore and shallow fresh water vegetation. This seems to be in agreement with the preliminary observations of the fossil diatom contents, which show a diatom flora mainly composed of benthic and tychoplanktonic species, indicating a shallow freshwater lake. Both diatomite sequences thus suggest shallow lakes throughout their deposition-whether this is due to their marginal position within the large calderas and/or shallow waters covered the entire calderas is an outstanding question that will be addressed with planned additional investigations. Kröpelin, S. etal (2015): New data on the unresolved paradox of the Tibesti crater paleolakes (Central Sahara, North Chad). Abstract #64322 AGU-Fall-Meeting-2015.

  15. Series of Case Patients with Nontuberculous Mycobacteria Isolation, Central North Carolina, 2006-2010

    EPA Science Inventory

    Nontuberculous mycobacteria (NTM) infection/colonization, associated with human morbidity/mortality, is linked to drinking water and drinking water distribution systems. To characterize rates and distribution of NTM isolation among residents living in three North Carolina countie...

  16. Analyses and descriptions of geochemical samples, central part of the Southern Nantahala Wilderness, Rabun and Towns Counties, Georgia, and Clay and Macon Counties, North Carolina

    SciTech Connect

    Adrian, B.M.; Peper, J.D.; Fairfield, R.J.; Laudon, L.S.; Edwards, C.A.

    1989-01-01

    A U.S. Geological Survey report is presented giving analyses and descriptions of geochemical samples, central part of the southern Nantahala Wilderness, Rabun and Towns Counties, Georgia, and Clay and Macon Counties, North Carolina.

  17. High frequency measurements of dissolved inorganic and organic nutrients using instrumented moorings in the southern and central North Sea

    NASA Astrophysics Data System (ADS)

    Suratman, Suhaimi; Weston, Keith; Greenwood, Naomi; Sivyer, David B.; Pearce, David J.; Jickells, Tim

    2010-05-01

    The aim of this study was to investigate the cycling of dissolved inorganic and organic nutrients using moored instrumented buoys (SmartBuoys) during the spring bloom in the North Sea. The instrumentation on the buoys enabled high frequency measurements of water-column integrated irradiance and in situ chlorophyll to be made, and also preserved water sample collection which were used for dissolved inorganic and organic nutrient analyses. The SmartBuoys were located in the year-round well-mixed plume zone associated with the River Thames and in the summer stratified central North Sea. These site locations allowed comparison of nutrient concentrations and cycling, and spring bloom development at two contrasting sites. The spring bloom was expected to be initiated at both stations due to increasing insolation and decreasing suspended load leading to higher water-column integrated irradiance. Due to differences in suspended load between the sites, the spring bloom started ˜2 months earlier in the central North Sea. The spring bloom in the Thames plume also resulted in higher maximum phytoplankton biomass due to the higher pre-bloom nutrient concentrations associated with riverine input. The use of SmartBuoys is also shown to allow the cycling of dissolved organic nutrients to be examined over the critical, and often undersampled, spring bloom period. Dissolved Organic Nitrogen (DON) clearly increased during the spring bloom in the central North Sea compared to winter concentrations. DON also increased in the Thames plume although showing greater winter variability related to higher riverine and sedimentary dissolved organic matter input at this shallow (˜18 m) coastal site. DON increase during the spring bloom was therefore related to primary production at both sites probably due to active release by phytoplankton. At both stations DON decreased to pre-bloom concentrations as the bloom declined suggesting the released DON was bioavailable and removed due to

  18. Tree-ring records of near-Younger Dryas time in central North America - Preliminary results from the Lincoln quarry site, central Illinois, USA

    USGS Publications Warehouse

    Panyushkina, Irina P.; Leavitt, Steven W.; Wiedenhoeft, A.; Noggle, S.; Curry, B.; Grimm, E.

    2004-01-01

    The abrupt millennial-scale changes associated with the Younger Dryas (YD) event ("chronozone") near the dawn of the Holocene are at least hemispheric, if not global, in extent. Evidence for the YD cold excursion is abundant in Europe but fairly meager in central North America. We are engaged in an investigation of high-resolution environmental changes in mid-North America over several millennia (about 10,000 to 14,000 BP) during the Late Glacial-Early Holocene transition, including the YD interval. Several sites containing logs or stumps have been identified and we are in the process of initial sampling or re-sampling them for this project. Here, we report on a site in central Illinois containing a deposit of logs initially thought to be of YD age preserved in alluvial sands. The assemblage of wood represents hardwood (angiosperm) trees, and the ring-width characteristics are favorable to developing formal tree-ring chronologies. However, 4 new radiocarbon dates indicate deposition of wood may have taken place over at least 8000 14C yr (6000-14,000 BP). This complicates the effort to develop a single floating chronology of several hundred years at this site, but it may provide wood from a restricted region over a long period of time from which to develop a sequence of floating chronologies, the timing of deposition and preservation of which could be related to paleoclimatic events and conditions.

  19. Assessment of sea surface temperature variations in the central North Atlantic using the alkenone unsaturation index (U 37k')

    NASA Astrophysics Data System (ADS)

    Villanueva, Joan; Grimalt, Joan O.; Cortijo, Elsa; Vidal, Laurence; Labeyrie, Laurent

    1998-07-01

    A high resolution record of U 37k' -derived SST estimations has been obtained in a core from the central North Atlantic Ocean (SU90/08, 43°30'N, 30°24'W) spanning a time period of 280 ky. The general trend of the U 37k' profile parallels closely the δ 180 signal and represent an independent confirmation that the SST variations in the glacial-interglacial time scales are correlated with the northern ice sheets evolution. In contrast to the CLIMAP (1984) conclusions based on the foraminiferal transfer function technique, the SST during the last interglacial period (LIP, isotopic stage 5.5) are 2-3°C warmer than during the Holocene. This result is in good agreement with many studies based in coastal and continental records that strongly suggest warmer climatic conditions over North America and Europe. Finally, the SST estimates during the last glacial maximum (LGM, 18 ky BP) where 4.5°C cooler than during the previous glacial period (PGP, stage 6). We argue that this difference is caused by a northward position of the polar front during the PGP in the Central North Atlantic.

  20. Hydrology and model of North Fork Solomon River Valley, Kirwin Dam to Waconda Lake, north-central Kansas

    USGS Publications Warehouse

    Jorgensen, Donald G.; Stullken, Lloyd E.

    1981-01-01

    The alluvial valley of the North Fork Solomon River is an important agricultural area. Reservoir releases diverted below Kirwin Dam are the principal source of irrigation water. During the 1970'S, severe water shortages occurred in Kirwin Reservoir and other nearby reservoirs as a result of an extended drought. Some evidence indicates that surface-water shortages may have been the result of a change in the rainfall-runoff relationship. Examination of the rainfall-runoff relationship shows no apparent trend from 1951 to 1968, but annual records from 1969 to 1976 indicate that deficient rainfall occurred during 6 of the 8 years. Ground water from the alluvial aquifer underlying the river valley also is used extensively for irrigation. Utilization of ground water for irrigation greatly increased from about 200 acre-feet in 1955 to about 12,300 acre-feet in 1976. Part of the surface water diverted for irrigation has percolated downward into the aquifer raising the ground-water level. Ground-water storage in the aquifer increased from 230,000 acre-feet in 1946 to 275,000 acre-feet in 1976-77. A digital model was used to simulate the steady-state conditions in the aquifer prior to closure of Kirwin Dam. Model results indicated that precipitation was the major source of recharge to the aquifer. The effective recharge, or gain from precipitation minus evapotranspiration, was about 11,700 acre-feet per year. The major element of discharge from the aquifer was leakage to the river. The simulated net leakage (leakage to the river minus leakage from the river) was about 11,500 acre-feet per year. The simulated value is consistent with the estimated gain in base flow of the river within the area modeled. Measurements of seepage used to determine gain and loss to the stream were made twice during 1976. Based on these measurements and on base-flow periods identified from hydrographs, it was estimated that the ground-water discharge to the stream has increased about 4,000 acre

  1. Mineralization potential along the trend of the Keweenawan- age Central North American Rift System in Iowa, Nebraska, and Kansas

    USGS Publications Warehouse

    Berendsen, P.

    1989-01-01

    The tectonic and sedimentary environment of the Central North American Rift System (CNARS) provides an excellent setting for major mineral deposits. Major north-northeast-trending high-angle normal or reverse faults and northwest-trending transcurrent fault systems may exercise control over ore forming processes. Gabbro and basalt are the dominant igneous rock types. Carbonatite and kimberlite occur in Nebraska and Kansas. Concentrations of Cu, Ni, Co, Ti, Au, Ag and PG minerals are known to occur in this setting. Arkosic sandstone, siltstone, shale, and minor carbonate units occur on top of the rift basalts and in flanking basins where they may reach thicknesses of 10 km (6 miles). The potential for stratiform or unconformity-related metalliferous deposits should be considered. The rift as a whole remains largely unexplored.

  2. Multiple Magmatic Events Over 40 Ma in the Fish Creek Mountains, North-central Great Basin, Nevada, USA

    NASA Astrophysics Data System (ADS)

    Cousens, B.; Henry, C. D.; Stevens, C.; Varve, S.

    2011-12-01

    The Fish Creek Mountains, located in north-central Nevada south of Battle Mountain, is a site of multiple igneous events ranging from ca. 35 Ma to 1 Ma, covering most of the igneous history of the Great Basin of the western United States. Such extended volcanic activity allows for documentation of mantle sources and petrogenetic processes over time. Beginning approximately 50 Ma, the Great Basin experienced a magmatic front that began migrating southwestward across southern Idaho, central Oregon and into northern Nevada and Utah. Intermediate, "arc-like" andesite and dacite dominated volcanic activity in northeastern Nevada between about 45 and 36 Ma. By 34 Ma, a northwest-trending belt of rhyolitic ash-flow calderas began to develop through central Nevada, the "ignimbrite flare-up". Volcanism then migrated westwards towards the Sierra Nevada. In north-central Nevada, the oldest lavas are ca. 35 Ma basaltic andesites through rhyolites that are exposed in the western Shoshone Range, the eastern Tobin Range, and the northern and eastern Fish Creek Mountains. Plagioclase-rich andesites, dacite intrusions, and volcanic breccias occur in a belt along the western side of the Fish Creek Mountains. The bulk of the Fish Creek Mountains is composed of the 24.7 Ma Fish Creek Mountains rhyolitic tuff that is largely confined to an undeformed caldera structure. The caldera and tuff are anomalously young compared to nearby felsic centers such as the Caetano caldera (33.8Ma) and Shoshone Range (39-35 Ma) and relative to the southwest to west magmatic migration. The basal tuff is unwelded, with abundant pumice and lithic (primarily volcanic) fragments but only rare crystals. Sanidine and smoky quartz phenocrysts become more abundant upsection and glassy fiamme (hydrated to devitrified) are common, but the abundance of lithic fragments diminishes. 16-15 Ma volcanic rocks of the Northern Nevada Rift are exposed in the Battle Mountain area, ranging in composition from subalkaine

  3. The 1996-2002 Plunge in the North-Atlantic Oscillation Index Produces Cold Spring Temperatures in Central Europe

    NASA Technical Reports Server (NTRS)

    Atlas, Robert (Technical Monitor); Otterman, Joseph; Atlas, Robert; Bungato, Dennis; Chou, Shu-Hsien; Koslowsky, Dirk; Rogers, Jeffrey; Wos, Alojzy

    2002-01-01

    Surface-air temperatures in winter and spring in central Europe rose over the second half of the 20th century, reported for different data-spans, and by different approaches (Ross et al., 1996; Angell, 1999; Hansen et al., 1999; Demaree et al., 2002). Analysis with a finer temporal resolution shows that late-winter and early-spring (February and March) trends are much stronger than the 3-month season averages (Otterman et al., 2002a). Responding to this need for finer than 3- month resolution, observations at meteorological stations in central Europe are analyzed here for the years 1951-2002, computing six-pentad (5-day period) averages (effectively monthly averages for January, February, and March). The daily minimum surface-air temperature, T(sub min), and the daily maximum temperature, T(sub max), rose steeply in Berlin and Poznan' in the years 1951-1995. Based on sensitivity studies, the bulk of this sharp warming is due to stronger southwesterlies over the North Atlantic, with which the temperatures in Europe are strongly correlated (Otterman et al., 1999; 2002a). However, for the most recent seven years, a pronounced downturn of the warming is observed, which we attribute to the concurrent, 1996-2002, sharp downturn of the ocean-surface southwesterlies over the North Atlantic (Otterman et al., 2002b). Such changes in the ocean winds and variations in the storm tracks are associated with changes in the North Atlantic Oscillation, NAO (Rogers, 1997). The NAO index, the difference in the surface pressure between Iceland and Azores, constitutes a measure of the zonal winds over the eastern North Atlantic, and thus is a critically important factor influencing the flow of maritime air into Europe (but the temperature of the advected airmasses depends on the meridional component, as we discuss). The recent (1996-2002) downturn in this index resulted in much colder spring temperatures in Europe, with adverse significance for the growing season.

  4. Distribution and behavior of scavenging amphipods from the central North Pacific

    NASA Astrophysics Data System (ADS)

    Ingram, Camilla L.; Hessler, Robert R.

    1983-07-01

    Deep-sea scavenging amphipod distributions, abundance, and behavior were studied with five-vehicle baited traps. The species composition and numerical abundances were comparable in the areas sampled. All size classes of the four predominant species ( Paralicella caperesca, P. tenuipes, Orchomene gerulicorbis, and Eurythenes gryllus) were trapped including sexually mature individuals, but no females were ovigerous. The central North Pacific E. gryllus is morphologically distinct from Atlantic E. gryllus and may represent a different species. Pelagic and demersal amphipod guilds exist, as determined by body size and vertical and horizontal distributional patterns. The demersal guild is composed of P. caperesca, P. tenuipes, and O. gerulicorbis, all of which are <2 cm in total body length and occur within 1 m of the sediment. E. gryllus, the only representative of the pelagic guild, ranges between 1.7 and 14 cm in total body length and has its greatest abundance several to tens of meters above the sediment. Members of the demersal guild probably can detect and exploit both large and small food falls or autochthonous organic particles because of their proximity to the sediment. They reside within the area of the benthic boundary layer where currents are slowest, and the diffusion of odor is slower than higher in the water column, thus reducing the area from which they can be attracted to a food item. The vertical distribution of E. gryllus correlates well with several physical features of the benthic boundary layer. Their vertical abundance increases an order of magnitude near the top of the Ekman layer, correlating with the increase in current velocities. It continues to increase up to 20 m, corresponding with the probable vertical extent of more than two-thirds of an odor trace. Their abundance decreases significantly above 20 m. The above correlations imply that the vertical distribution of E. gryllus is an adaptation that provides a wide chemosensory overview of

  5. Wildfire effects on soil lipid composition in burnt eucalypt stands, in north-central Portugal

    NASA Astrophysics Data System (ADS)

    Faria, Sílvia; De la Rosa, José Maria; Knicker, Heike; González-Pérez, José A.; González-Vila, Francisco J.; Keizer, Jan Jacob

    2013-04-01

    Wildfires can induce profound changes in the quality and quantity of soil organic matter (SOM) pools. Early detection of fire impacts on SOM pools is relevant for taking decision and planning of post-fire restoration actions, since SOM plays a key role in post-fire erosion risk and the recovery of fire-affected ecosystems. This work focuses on wildfire effects on the composition of lipids in the topsoil of eucalypt plantations, one of the prevailing and, at the same time, most fire-prone forest types in north-central Portugal. To this end, two neighbouring eucalypt plantations were sampled at 5 occasions with roughly 6-monthly intervals, starting immediately after a wildfire in August 2010 till August 2012. One of the study sites was located within the 2010-bunrt area and the other just outside it. The air-dry soil samples were treated with a dichloromethane-methanol (3:1) mixture for Soxhlet extraction of the SOM's labile lipid fraction, as this fraction is particularly prone to undergo rapid and significant alterations by fire-induced heating. In turn, these alterations have elevated potential to be used as markers of direct fire effects on soil properties in general and, at the same time, as indicators of the recovery process during the so-called window-of-disturbance. The lipid compositions of the samples were determined by GC-MS. The preliminary results of this study indicated that the soil lipid fraction of the upper soil layer (0-2 cm depth) decreased sharply due to the wildfire, and that this effect lasted for more than 24 months. Its contents in the different sampling periods varied between 2.4 and 5.7 % at the long-unburnt site as compared to 0.9 - 1.1 % at the burnt site. The main differences between the burnt and unburnt samples were found in the distribution patterns of alkyl compounds. Without exception, an accumulation of low molecular weight homologues was observed in the burnt samples, suggesting that fire led to thermal breakdown and cracking of

  6. Estimation of evapotranspiration in the Rainbow Springs and Silver Springs basins in North-Central Florida

    USGS Publications Warehouse

    Knowles, Leel, Jr.

    1996-01-01

    Estimates of evapotranspiration (ET) for the Rainbow and Silver Springs ground-water basins in north-central Florida were determined using a regional water-~budget approach and compared to estimates computed using a modified Priestley-Taylor (PT) model calibrated with eddy-correlation data. Eddy-correlation measurements of latent 0~E) and sensible (H) heat flux were made monthly for a few days at a time, and the PT model was used to estimate 3,E between times of measurement during the 1994 water year. A water-budget analysis for the two-basin area indicated that over a 30-year period (196594) annual rainfall was 51.7 inches. Of the annual rainfall, ET accounted for about 37.9 inches; springflow accounted for 13.1 inches; and the remaining 0.7 inch was accounted for by stream-flow, by ground-water withdrawals from the Floridan aquifer system, and by net change in storage. For the same 30-year period, the annual estimate of ET for the Silver Springs basin was 37.6 inches and was 38.5 inches for the Rainbow Springs basin. Wet- and dry-season estimates of ET for each basin averaged between nearly 19 inches and 20 inches, indicating that like rainfall, ET rates during the 4-month wet season were about twice the ET rates during the 8-month dry season. Wet-season estimates of ET for the Rainbow Springs and Silver Springs basins decreased 2.7 inches, and 3.4 inches, respectively, over the 30-year period; whereas, dry-season estimates for the basins decreased about 0.4 inch and1.0 inch, respectively, over the 30-year period. This decrease probably is related to the general decrease in annual rainfall and reduction in net radiation over the basins during the 30-year period. ET rates computed using the modified PT model were compared to rates computed from the water budget for the 1994 water year. Annual ET, computed using the PT model, was 32.0 inches, nearly equal to the ET water-budget estimate of 31.7 inches computed for the Rainbow Springs and Silver Springs basins

  7. GIS-analysis of gully erosion susceptibility: a key study in north-central Sicily, Italy

    NASA Astrophysics Data System (ADS)

    Agnesi, Valerio; Angileri, Silvia; Cappadonia, Chiara; Conoscenti, Christian; Costanzo, Dario; Maerker, Michael; Rotigliano, Edoardo

    2010-05-01

    Erosion by water is responsible for severe geo-environmental problems in semi-humid to arid Mediterranean areas. Large sectors of Sicily are affected by intense soil erosion phenomena leading to severe damages in agriculture lands that, in some cases, experience high soil loss rates. An important contribution to sediment yield from these areas is given by gully erosion phenomena; the latter, in the last decades, attracted attention of many researches that developed and applied methods to quantify soil loss volumes and to evaluate proneness of territory to this process. The present research aims to assess gully erosion susceptibility in the basin of the San Giorgio torrent, a mountain stream flowing in north-central Sicily and draining an area of about 9.5 km2; the watershed, which is mainly covered by arable lands, has highly erodible slopes characterized by the outcropping of clays and marls. In order to predict gully erosion susceptibility, a multivariate geostatistical approach is adopted here. In particular, the method is based on the definition of spatial relationships between the geographical variability of a set of controlling factors and the occurrence of gullies on slopes; the linear density of gullies computed on homogeneous domains is selected as the probabilistic function expressing how proneness to gully erosion spatially changes in the studied area. Available thematic maps, which were integrated by field and remote surveys, and a high quality DEM, were used to derive eight layers of terrain variables, selected according to geomorphological criteria and expressing both soil erodibility (bedrock lithology, land use) and erosivity of flowing waters (slope angle, Stream Power Index, SL-factor, Topographic Wetness Index, plan and profile curvature). All the parameters were computed for homogeneous spatial domains, created by intersecting a grid of 50m square polygons and a layer of slope units automatically derived from DEM; therefore, the eight layers

  8. Discovery of 3 km long seafloor fracture system in the Central North Sea

    NASA Astrophysics Data System (ADS)

    Pedersen, R. B.; Blomberg, A.; Landschulze, K.; Baumberger, T.; Økland, I.; Reigstad, L.; Gracias, N.; Mørkved, P. T.; Stensland, A.; Lilley, M. D.; Thorseth, I. H.

    2013-12-01

    We have discovered a 3 km long seafloor fracture system in the Central North Sea (block 16/4). The discovery was made using a synthetic aperture sonar (HISAS) mounted on a Kongsberg Hugin AUV. The surface expression of the structure - named the Hugin Fracture - changes along the strike and it is characterized by: 1) linear; 2) en echelon; and 3) branching segments. Ring-structures, that typically are 5-10 meters across, are common along the feature. Micro-bathymetry acquired using the HISAS system demonstrates that sub-meter scale elevation changes occur across the fracture. Microbial mats occur along different parts of the structure showing that active seepage is taking place. AUV based photo-imaging of parts of the structure shows that the microbial mats predominantly are associated with ring structures and some of the linear fracture segments. Sediment pore waters extracted from push cores show Na, Cl and Mg contents that are 10-15% lower compared to background pore fluid concentrations. This points towards a fresh water input. The fracture pore fluid compositions are also characterized by elevated methane, ammonium and hydrogen sulphide contents compared to the background seawater. The presence of these volatiles is likely caused by subsurface microbial activity, and carbon isotope analyses confirm a biological source of the detected methane. However, the presence of ethane (CH4/C2H6 of 126) indicates a small input of a thermogenic carbon to these fluids. Subsurface imaging using a hull mounted parametric sub bottom profiler reveal Holocene stratified sediments overlying quaternary moraine in the area. The sub bottom profiler data show sub-meter scale vertical movements along the fracture. Associated with the structures are small bright spots that may reflect gas accumulations. No deep-seated fault system is apparent below the fracture in 3D seismic data from the area. However, the 3D seismic data show that the structure is located above the boundary of a

  9. Healdsburgite - a New Tektite and Associated Tektite Strewnfield in North Central California

    NASA Astrophysics Data System (ADS)

    Erickson, R. C.; Deino, A. L.; Norwick, S. A.; Byrd, C.

    2012-12-01

    Erickson, Rolfe; Norwick, Steven; and Byrd, Caitlin, Sonoma State University; Deino, Alan, Berkeley Geochronology Center. I A Distinctive Glass Clast Population In numerous locations in Sonoma and Solano Counties in north central California, over an area of ~ 200 km2, distinctive ~ 1-5 cm dominantly ovoid glass clasts are found as part of the pebble population in young sediments. They are composed of black massive aphyric nonvesicular glass whose surfaces are totally covered with a texture of adjoining small deep pits and grooves. The pits are hemispherical, 1-10 mm across, and join at sharp edges composed of straight segments. The grooves, where present, are the width and depth of the pits and may be up to several cm long and vermicular. Some clasts have internal layering resembling flow textures. These glass objects were brought to our attention by a local resident, Ms. Diane Moore, about 20 years ago. Four of these glass clasts from widely separated locations in the exposure area have been dated by the laser incremental-heating Ar39/Ar40 method at the Berkeley Geochronology Center, with an age of ~ 2.81 Ma (upper Pliocene). The four samples have mutually overlapping ages at one sigma. Chemical analyses of the 10 major and 50 minor elements, of four widely separated clasts, were obtained at commercial laboratories. The clasts are all rhyolites and cluster tightly on the TAS diagram of Le Maitre et al (2002). All available data show that all these pitted and grooved clasts are part of a single population. II. The Clasts are Tektites We believe these distinctive glass clasts to be tektites for the following reasons: 1. Pits are always present and wholly cover the clast surface. Perhaps half the clasts also have distinctive irregular vermicular grooves superimposed on the pitted surface. This surface pattern is like those on other long-recognized 'classic' tektites, like indochinites. The clasts look like tektites; compare McCall (2001, Figure 2.30) for example. 2

  10. Thrust belt Formation followed by Back-Arc Extension: Mantle Dynamics from central North Island, New Zealand.

    NASA Astrophysics Data System (ADS)

    Stern, T.; Stratford, W.; Salmon, M.; Pulford, A.

    2008-12-01

    In central North Island a useful geological and geophysical data exists to examine the evolution from retro-arc compression to back-arc extension in the Neogene. We show that the switch from compression to extensional deformation is related in space and time with an event that rapidly removed much of the mantle lithosphere beneath central and western North Island at about 5 Ma. The geophysical smoking gun for this removal process is in two parts: a regional surface uplift at about 5 Ma, and a sharp east-west, lithospheric boundary across which there is a 7 km jump in Moho as determined by a common conversion point stack of receiver functions. Also associated with the boundary is sharp change in mantle properties such as seismic P-wave attenuation, isostatic gravity and Pn wave speeds. A cluster of earthquakes in the depth range 20-35 km tightly correlates with the Moho step. Thickening then removal of mantle lithosphere within central and western North Island is consistent with its geological history. About 20 my of compression and fold and thrust development within western North Island built much of the Taranaki (foreland) basin during the Miocene. This 600 km long and 200 km wide basin is now the principal source of hydrocarbons for New Zealand. Up to 100 km of shortening in both crust and mantle is estimated from deep seismic reflection profiling, subsidence curves and plate reconstructions. At the close of the Miocene thrusting ceased and a rapid (post 5 Ma) and regional (400 km wide) exhumation event began. Based on mudstone porosity data, a maximum 2.5 km of rock uplift (1 km of surface uplift) occurred and this gave shape to much of the North Island land mass as we see today. The edge of the foreland basin was exhumed by up to 1.5 km and oil wells drilled in the margin date this event as starting at 5 Ma. After 5 Ma a switch to extension occurred with present day back-arc extension occurring at rates between 8-20 mm/y. This extension is accompanied by

  11. Wood resources and utilization patterns in the North Central Region and energy needs for the manufacture of wood products

    SciTech Connect

    Sinclair, S.A.

    1981-03-01

    The timber resources of the North Central Region are discussed on a state-by-state basis. The discussion of standing timber growth and removal is in terms of commercial growing stock; however, the total forest biomass may be estimated by simply adding the potential logging residue to the growing stock figure. The energy needs of various wood and paper products plants, Standard Industrial Classification (SIC) Codes 24 and 26, are highlighted. In addition, the ability of various wood manufacturing facilities to generate their energy needs from wood residues and by-products is explored.

  12. Food of Flesh-footed shearwaters Puffinus carneipes associated with high-seas driftnets in the central North Pacific Ocean

    USGS Publications Warehouse

    Gould, P.; Ostrom, P.; Walker, W.

    1997-01-01

    We examined digestive tract contents and stable nitrogen isotope ratios in breast muscles of Flesh-footed Shearwaters Puffinus carneipes associated with high-seas driftnet fisheries in the central North Pacific Ocean. Small fish, Lanternfish (Myctophidae) and Pacific Saury Cololabis saira, were the principal prey found in the digestive tracts. Pieces of unidentified fish, possibly Pacific Pomfret Brama japonica, and shredded squid tissue, mostly Neon Flying Squid Ommastrephes bartrami, in the digestive tracts indicate scavenging at driftnet fishing operations. Although softbodied animals such as Velella sp. were rare in the digestive tracts, low stable nitrogen isotope values (??15N) suggest Flesh-footed Shearwaters feed heavily on such low trophic level animals.

  13. Chemistry of atmospheric precipitation in the north-central united states: Influence of sulfate, nitrate, ammonia and calcareous soil particulates

    NASA Astrophysics Data System (ADS)

    Munger, James William

    The supply of alkaline soil dust and gaseous NH 3 available to neutralize anthropogenic acids in the atmosphere controls the acidity of precipitation in the north-central United States. Major ions and trace metals were determined in precipitation-event and snow-core samples from sites along a 600 km transect from the North Dakota prairie to the forests of northeastern Minnesota, collected during the period April 1978-June 1979. Acidity increased 4-fold from west to east as the effect of alkaline dust and NH 3 decreased with increasing distance from the cultivated prairie; calcium and Mg 2+ decreased 2 to 3-fold across the transect. However, minimum concentrations of NH 4+ and SO 42- were observed at Itasca, the central site. Natural emissions of these elements were important in the west, while anthropogenic emissions were responsible for the higher concentrations in the east. Wet deposition of H + decreased 8-fold and deposition of NO 3- and SO 42- decreased 1.5 to 2-fold from Hovland in the east to Tewaukon in the west. Wet deposition of the metal cations increased from Hovland to Tewaukon. Dry deposition followed a similar trend. Winter snow cover and freezing temperatures, which decreased airborne soil dust and the evolution of NH 3 from the prairie soils, led to an increase in precipitation acidity at all sites. The acid increase was accompanied by a decrease in alkaline metal cations, especially Ca 2+, and in NH 4+. At Hovland SO 42- and NO 3- also increased during the winter. The occurrence of snow events at Tewaukon that were appreciably more acid than the snowpack accumulated there indicates that snow was neutralized after it fell by alkaline dust entrained in resuspended snow, or deposited separately. Winter inputs of acid are especially important because they are released during a short period in the spring. Over half of the acid input at Hovland occurred during the winter. Precipitation inputs of P and N probably benefit nutrient-poor ecosystems in the

  14. Paleocene Paleomagnetic Pole for north America from alkalic intrusions, central Montana

    SciTech Connect

    Jacobson, D.; Beck, M.E. Jr.; Diehl, J.F.; Hearn, B.C. Jr.

    1980-07-01

    The apparent polar wandering path from Late Cretaceous through early Tertiary time is not well defined. We have collected 33 paleomagnetic sites from the Paleocena Moccasin, Judith, and Little Rocky Mountains and from these a North American Paleocene paleomagnetic pole position has been determined at 174.9 /sup 0/W long., 80.5 /sup 0/N lat., with a circle of 95% confidence of 3.6 /sup 0/. This pole location serves as a Paleocene reference pole and enhances the North America apparent polar wandering path for a critical period of its history.

  15. Glacial-eustatic sea-level curve for early Late Pennsylvanian sequence in north-central Texas and biostratigraphic correlation with curve for midcontinent North America

    SciTech Connect

    Boardman, D.R. II ); Heckel, P.H. )

    1989-09-01

    At least 30 transgressive-regressive cycles of deposition are recognized from the upper Desmoinesian East Mountain Shale to the mid-Virgilian Wayland Shale in north-central Texas. Maximum regressive deposits are typically paleosol mudstones and fluvial sandstones; maximum transgressive deposits are typically widespread, ammonoid-bearing, conodont-rich, dark phosphatic shales in more major cycles, and persistent fossiliferous shales or limestones overlying terrestrial deposits in more minor cycles. Delta complexes dominate the regressive sequences of many cycles. Using biostratigraphic criteria of first, last, sole, or acme occurrence of ammonoid, conodont, and fusulinid taxa, the authors correlate 17 cycles in the Texas sequence directly with 17 glacial-eustatic cycles of similar magnitude in the northern midcontinent. This correlation suggests that glacial eustacy was the basic control over the cyclic sequence in Texas, that tectonic masking of the eustatic signal by nearby orogenic movement in Texas was negligible, and that delta shifting, though conspicuous, was only a secondary control over the cyclicity there. Minor cycles recognized between the correlated cycles also match well enough between Texas and the midcontinent to further discount potential tectonic or deltaic masking of glacial-eustatic cyclicity. This strengthens the likelihood of correlating glacial-eustatic events across larger parts of North America, and perhaps with other parts of the world.

  16. Cretaceous stratigraphic sequences of north-central California suggest a discontinuity in the Late Cretaceous forearc basin

    SciTech Connect

    Haggart, J.W.

    1986-10-01

    The Cretaceous sedimentary succession preserved east of Redding, at the northern end of California's Great Valley, indicates that marine deposition was widespread in the region for only two periods during the Late Cretaceous. If it is assumed that there was minimal Cenozoic offset between the northern Sierra Nevada and eastern Klamath Mountains terranes, Cretaceous sedimentation in this region was most likely restricted to a narrow trough and was not a continuation of the wide, Cretaceous forearc basin of central California. The dissimilar depositional histories of the Redding basin and the Hornbrook basin of north-central California suggest that the basins were not linked continuously during the Late Cretaceous. A thick section of Cretaceous strata beneath the southwestern Modoc Plateau is considered unlikely.

  17. Recent viroid disease outbreaks in greenhouse tomatoes in North and Central America and their management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouse tomato productions in North America have suffered from several high profile viroid disease outbreaks in recent years. In this presentation, I will summarize and briefly describe each of these viroid disease outbreak and their relationship. What are viroids and their transmission through ...

  18. Coal Rank and Stratigraphy of Pennsylvanian Coal and Coaly Shale Samples, Young County, North-Central Texas

    USGS Publications Warehouse

    Guevara, Edgar H.; Breton, Caroline; Hackley, Paul C.

    2007-01-01

    Vitrinite reflectance measurements were made to determine the rank of selected subsurface coal and coaly shale samples from Young County, north-central Texas, for the National Coal Resources Database System State Cooperative Program conducted by the Bureau of Economic Geology at The University of Texas at Austin. This research is the continuation of a pilot study that began in adjacent Archer County, and forms part of a larger investigation of the coalbed methane resource potential of Pennsylvanian coals in north-central Texas. A total of 57 samples of coal and coaly shale fragments were hand-picked from drill cuttings from depths of about 2,000 ft in five wells, and Ro determinations were made on an initial 10-sample subset. Electric-log correlation of the sampled wells indicates that the collected samples represent coal and coaly shale layers in the Strawn (Pennsylvanian), Canyon (Pennsylvanian), and Cisco (Pennsylvanian-Permian) Groups. Coal rank in the initial sample subset ranges from lignite (Ro=0.39), in a sample from the Cisco Group at a depth of 310 to 320 ft, to high volatile bituminous A coal (Ro=0.91) in a sample from the lower part of the Canyon Group at a depth of 2,030 to 2,040 ft.

  19. Phylogeny and Niche Conservatism in North and Central American Triatomine Bugs (Hemiptera: Reduviidae: Triatominae), Vectors of Chagas' Disease

    PubMed Central

    Ibarra-Cerdeña, Carlos N.; Zaldívar-Riverón, Alejandro; Peterson, A. Townsend; Sánchez-Cordero, Víctor; Ramsey, Janine M.

    2014-01-01

    The niche conservatism hypothesis states that related species diverge in niche characteristics at lower rates than expected, given their lineage divergence. Here we analyze whether niche conservatism is a common pattern among vector species (Hemiptera: Reduviidae: Triatominae) of Trypanosoma cruzi that inhabit North and Central America, a highly heterogeneous landmass in terms of environmental gradients. Mitochondrial and nuclear loci were used in a multi-locus phylogenetic framework to reconstruct phylogenetic relationships among species and estimate time of divergence of selected clades to draw biogeographic inferences. Then, we estimated similarity between the ecological niche of sister species and tested the niche conservatism hypothesis using our best estimate of phylogeny. Triatoma is not monophyletic. A primary clade with all North and Central American (NCA) triatomine species from the genera Triatoma, Dipetalogaster, and Panstrongylus, was consistently recovered. Nearctic species within the NCA clade (T. p. protracta, T. r. rubida) diverged during the Pliocene, whereas the Neotropical species (T. phyllosoma, T. longipennis, T. dimidiata complex) are estimated to have diverged more recently, during the Pleistocene. The hypothesis of niche conservatism could not be rejected for any of six sister species pairs. Niche similarity between sister species best fits a retention model. While this framework is used here to infer niche evolution, it has a direct impact on spatial vector dynamics driven by human population movements, expansion of transportation networks and climate change scenarios. PMID:25356550

  20. Contribution of cephalopod prey to the diet of large pelagic fish predators in the central North Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Logan, John M.; Toppin, Rebecca; Smith, Sean; Galuardi, Benjamin; Porter, Julie; Lutcavage, Molly

    2013-10-01

    Trophic studies documenting the importance of cephalopod prey for large pelagic fish predators have been performed recently for open ocean ecosystems in the Pacific and Indian oceans, but similar data for the central North Atlantic Ocean have been lacking. A series of longline sampling cruises targeting large pelagic fish species was undertaken in the central North Atlantic Ocean in 2001-2002, and stomach samples were analyzed from a variety of tuna, shark, and billfish species to help fill this data gap. Stomach samples were collected from nine species (n=170 non-empty stomachs), with the majority of stomachs from Atlantic swordfish (Xiphias gladius; n=69), yellowfin tuna (Thunnus albacares; n=31), and albacore tuna (Thunnus alalunga; n=28). Ommastrephid squids were the most ubiquitous prey group across predator species and sampling years. Secondary cephalopod prey included octopods, histioteuthids, and architeuthids. Mesopelagic fishes and Sargassum-associated fishes were also identified as important prey. Diet composition varied spatially and prey size increased with predator size for swordfish and yellowfin tuna. Our results support findings in other ocean basins that demonstrate the importance of squid to large pelagic fishes and highlight the need for more research on their ecological and biophysical dynamics.

  1. Little Ice Age evidence from a south-central North American ice core, U.S.A.

    USGS Publications Warehouse

    Naftz, D.L.; Klusman, R.W.; Michel, R.L.; Schuster, P.F.; Ready, M.M.; Taylor, H.E.; Yanosky, T.M.; McConnaughey, E.A.

    1996-01-01

    In the past, ice-core records from mid-latitude glaciers in alpine areas of the continental United States were considered to be poor candidates for paleoclimate records because of the influence of meltwater on isotopic stratigraphy. To evaluate the existence of reliable paleoclimatic records, a 160-m ice core, containing about 250 yr of record was obtained from Upper Fremont Glacier, at an altitude of 4000 m in the Wind River Range of south-central North America. The ??18O (SMOW) profile from the core shows a -0.95??? shift to lighter values in the interval from 101.8 to 150 m below the surface, corresponding to the latter part of the Little Ice Age (LIA). Numerous high-amplitude oscillations in the section of the core from 101.8 to 150 m cannot be explained by site-specific lateral variability and probably reflect increased seasonality or better preservation of annual signals as a result of prolonged cooler temperatures that existed in this alpine setting. An abrupt decrease in these large amplitude oscillations at the 101.8-m depth suggests a sudden termination of this period of lower temperatures which generally coincides with the termination of the LIA. Three common features in the ??18O profiles between Upper Fremont Glacier and the better dated Quelccaya Ice Cap cores indicate a global paleoclimate linkage, further supporting the first documented occurrence of the LIA in an ice-core record from a temperate glacier in south-central North America.

  2. Evidence and implications for a grounded ice sheet in the Central North Sea in the early Pleistocene

    NASA Astrophysics Data System (ADS)

    Rea, Brice; Rose, Phil; Buckley, Francis; Cater, John; Spagnolo, Matteo; Archer, Stuart; Halliyeva, Maral; Howell, John; Cornwell, Dave; Basell, Jon

    2015-04-01

    The rich archive of industry 2D and 3D seismic dataprovide a major opportunity to enlighten us about the Quaternary glacial history of the British and Scandinavian Ice Sheets. Early Quaternary terrestrial records of glaciation are at best highly fragmentary and at worst non-existent and dominated for the most part, by the last deglaciation. The depo-centre along the Central Graben and Viking Graben contains a rich sedimentary archive approaching, in places, 1000 m thick. Evidence is reviewed, from existing and new work, including mapping from 3D seismic of diagnostic ice proximal and subglacial landforms, wireline log and core data. These data indicate that, not only was there grounded ice present on the periphery of the North Sea but, an ice sheet extended far into the Central North Sea. The timing of this is not fully constrained but is it significantly earlier than previously thought, and certainly occurs in the early Quaternary. The possible source areas for this ice sheet and mechanisms by which it could be so extensive early in the Quaternary are explored. These findings are contextualised in terms of other evidence for NW European ice masses from IRD, and evidence for extensive ice sheets in other parts of the world in the early Quaternary e.g. the Laurentide Ice Sheet. The implications for the regolith hypothesis, a mechanism by which orbital forcing is modulated by changing ice sheet dynamics, and landscape evolution are discussed.

  3. Recent increases in atmospheric deposition of mercury to North-Central Wisconsin lakes inferred from sediment analyses

    USGS Publications Warehouse

    Rada, R.G.; Wiener, J.G.; Winfrey, M.R.; Powell, D.E.

    1989-01-01

    Profiles of total mercury (Hg) concentrations in sediments were examined in 11 lakes in north-central Wisconsin having a broad range of pH (5.1 to 7.8) and alkalinity (-12 to 769 μeq/L). Mercury concentrations were greatest in the top 15 cm of the cores and were much lower in the deeper strata. The Hg content in the most enriched stratum of individual cores ranged from 0.09 to 0.24 μg/g dry weight, whereas concentrations in deep, precolonial strata ranged from 0.04 to 0.07 μg/g. Sediment enrichment factors varied from 0.8 to 2.8 and were not correlated with lake pH. The increase in the Hg content of recent sediments was attributed to increased atmospheric deposition of the metal. Eight of the 11 systems studied were low-alkalinity lakes that presumably received most (≥90%) of their hydrologic input from precipitation falling directly onto the lake surface. Thus, the sedimentary Hg in these lakes seems more likely linked to direct atmospheric deposition onto the lake surfaces than to influxes from the watershed. The data imply that a potentially significant fraction of the high Hg burdens measured in game fish in certain lakes in north-central Wisconsin originated from atmospheric sources.

  4. The ants of North and Central America: the genus Mycocepurus (Hymenoptera: Formicidae)

    PubMed Central

    Mackay, William P.; Maes, Jean-Michel; Fernández, Patricia Rojas; Luna, Gladys

    2004-01-01

    Abstract We provide a review of the North American ants (north of Colombia) of the ant genus Mycocepurus, including keys to the workers and females, illustrations and distribution maps. The distribution of M. tardus is extended to Nicaragua and Costa Rica. The female of M. curvispinosus is described. Resumen Se revisan las especies del género Mycocepurus de Norte América (al norte de Colombia). Se incluyen claves para la identificación de las obreras y las hembras, ilustraciones y mapas de distribución. Se amplia hacia el norte la distribución de M. tardus, incluyendo ahora Nicaragua y Costa Rica y se describe la hembra de M. curvispinosus. PMID:15861242

  5. Identifying Pelagic Habitat Hotspots of Neon Flying Squid in the Temperate Waters of the Central North Pacific.

    PubMed

    Alabia, Irene D; Saitoh, Sei-Ichi; Mugo, Robinson; Igarashi, Hiromichi; Ishikawa, Yoichi; Usui, Norihisa; Kamachi, Masafumi; Awaji, Toshiyuki; Seito, Masaki

    2015-01-01

    We identified the pelagic habitat hotspots of the neon flying squid (Ommastrephes bartramii) in the central North Pacific from May to July and characterized the spatial patterns of squid aggregations in relation to oceanographic features such as mesoscale oceanic eddies and the Transition Zone Chlorophyll-a Front (TZCF). The data used for the habitat model construction and analyses were squid fishery information, remotely-sensed and numerical model-derived environmental data from May to July 1999-2010. Squid habitat hotspots were deduced from the monthly Maximum Entropy (MaxEnt) models and were identified as regions of persistent high suitable habitat across the 12-year period. The distribution of predicted squid habitat hotspots in central North Pacific revealed interesting spatial and temporal patterns likely linked with the presence and dynamics of oceanographic features in squid's putative foraging grounds from late spring to summer. From May to June, the inferred patches of squid habitat hotspots developed within the Kuroshio-Oyashio transition zone (KOTZ; 37-40°N) and further expanded north towards the subarctic frontal zone (SAFZ; 40-44°N) in July. The squid habitat hotspots within the KOTZ and areas west of the dateline (160°W-180°) were likely influenced and associated with the highly dynamic and transient oceanic eddies and could possibly account for lower squid suitable habitat persistence obtained from these regions. However, predicted squid habitat hotspots located in regions east of the dateline (180°-160°W) from June to July, showed predominantly higher squid habitat persistence presumably due to their proximity to the mean position of the seasonally-shifting TZCF and consequent utilization of the highly productive waters of the SAFZ. PMID:26571118

  6. Identifying Pelagic Habitat Hotspots of Neon Flying Squid in the Temperate Waters of the Central North Pacific

    PubMed Central

    Alabia, Irene D.; Saitoh, Sei-Ichi; Mugo, Robinson; Igarashi, Hiromichi; Ishikawa, Yoichi; Usui, Norihisa; Kamachi, Masafumi; Awaji, Toshiyuki; Seito, Masaki

    2015-01-01

    We identified the pelagic habitat hotspots of the neon flying squid (Ommastrephes bartramii) in the central North Pacific from May to July and characterized the spatial patterns of squid aggregations in relation to oceanographic features such as mesoscale oceanic eddies and the Transition Zone Chlorophyll-a Front (TZCF). The data used for the habitat model construction and analyses were squid fishery information, remotely-sensed and numerical model-derived environmental data from May to July 1999–2010. Squid habitat hotspots were deduced from the monthly Maximum Entropy (MaxEnt) models and were identified as regions of persistent high suitable habitat across the 12-year period. The distribution of predicted squid habitat hotspots in central North Pacific revealed interesting spatial and temporal patterns likely linked with the presence and dynamics of oceanographic features in squid’s putative foraging grounds from late spring to summer. From May to June, the inferred patches of squid habitat hotspots developed within the Kuroshio-Oyashio transition zone (KOTZ; 37–40°N) and further expanded north towards the subarctic frontal zone (SAFZ; 40–44°N) in July. The squid habitat hotspots within the KOTZ and areas west of the dateline (160°W-180°) were likely influenced and associated with the highly dynamic and transient oceanic eddies and could possibly account for lower squid suitable habitat persistence obtained from these regions. However, predicted squid habitat hotspots located in regions east of the dateline (180°-160°W) from June to July, showed predominantly higher squid habitat persistence presumably due to their proximity to the mean position of the seasonally-shifting TZCF and consequent utilization of the highly productive waters of the SAFZ. PMID:26571118

  7. Estimation of speciated and total mercury dry deposition at monitoring locations in eastern and central North America

    USGS Publications Warehouse

    Zhang, L.; Blanchard, P.; Gay, D.A.; Prestbo, E.M.; Risch, M.R.; Johnson, D.; Narayan, J.; Zsolway, R.; Holsen, T.M.; Miller, E.K.; Castro, M.S.; Graydon, J.A.; St. Louis, V.L.; Dalziel, J.

    2012-01-01

    Dry deposition of speciated mercury, i.e., gaseous oxidized mercury (GOM), particulate-bound mercury (PBM), and gaseous elemental mercury (GEM), was estimated for the year 2008–2009 at 19 monitoring locations in eastern and central North America. Dry deposition estimates were obtained by combining monitored two- to four-hourly speciated ambient concentrations with modeled hourly dry deposition velocities (Vd) calculated using forecasted meteorology. Annual dry deposition of GOM+PBM was estimated to be in the range of 0.4 to 8.1 μg m−2 at these locations with GOM deposition being mostly five to ten times higher than PBM deposition, due to their different modeled Vd values. Net annual GEM dry deposition was estimated to be in the range of 5 to 26 μg m−2 at 18 sites and 33 μg m−2 at one site. The estimated dry deposition agrees very well with limited surrogate-surface dry deposition measurements of GOM and PBM, and also agrees with litterfall mercury measurements conducted at multiple locations in eastern and central North America. This study suggests that GEM contributes much more than GOM+PBM to the total dry deposition at the majority of the sites considered here; the only exception is at locations close to significant point sources where GEM and GOM+PBM contribute equally to the total dry deposition. The relative magnitude of the speciated dry deposition and their good comparisons with litterfall deposition suggest that mercury in litterfall originates primarily from GEM, which is consistent with the limited number of previous field studies. The study also supports previous analyses suggesting that total dry deposition of mercury is equal to, if not more important than, wet deposition of mercury on a regional scale in eastern North America.

  8. Thematic mapping, land use, geological structure and water resources in central Spain. [north of Madrid

    NASA Technical Reports Server (NTRS)

    Delascuevas, N. (Principal Investigator)

    1976-01-01

    The author has identified the following significant results. A method for a rapid updating of cartography at scale 1:200,000 was established. An annular tectonic structure was detected north of Madrid which was named Structural Halo of Guadalix, since its center is situated in the locality of Guadalix de la Sierra. This circular complex has from 30 to 40 km of radius and its influences at its most extreme edges reach Madrid.

  9. Multistory duplexes with forward dipping roofs, north central Brooks Range, Alaska

    USGS Publications Warehouse

    Wallace, W.K.; Moore, T.E.; Plafker, G.

    1997-01-01

    The Endicott Mountains allochthon has been thrust far northward over the North Slope parautochthon in the northern Brooks Range. Progressively younger units are exposed northward within the allochthon. To the south, the incompetent Hunt Fork Shale has thickened internally by asymmetric folds and thrust faults. Northward, the competent Kanayut Conglomerate forms a duplex between a floor thrust in Hunt Fork and a roof thrust in the Kayak Shale. To the north, the competent Lisburne Group forms a duplex between a floor thrust in Kayak and a roof thrust in the Siksikpuk Formation. Both duplexes formed from north vergent detachment folds whose steep limbs were later truncated by south dipping thrust faults that only locally breach immediately overlying roof thrusts. Within the parautochthon, the Kayak, Lisburne, and Siksikpuk-equivalent Echooka Formation form a duplex identical to that in the allochthon. This duplex is succeeded abruptly northward by detachment folds in Lisburne. These folds are parasitic to an anticlinorium interpreted to reflect a fault-bend folded horse in North Slope "basement," with a roof thrust in Kayak and a floor thrust at depth. These structures constitute two northward tapered, internally deformed wedges that are juxtaposed at the base of the allochthon. Within each wedge, competent units have been shortened independently between detachments, located mainly in incompetent units. The basal detachment of each wedge cuts upsection forward (northward) to define a wedge geometry within which units dip regionally forward. These dips reflect forward decrease in internal structural thickening by forward vergent folds and hindward dipping thrust faults. Copyright 1997 by the American Geophysical Union.

  10. Depositional sequence evolution, Paleozoic and early Mesozoic of the central Saharan platform, North Africa

    SciTech Connect

    Sprague, A.R.G. )

    1991-08-01

    Over 30 depositional sequences have been identified in the Paleozoic and lower Mesozoic of the Ghadames basin of eastern Algeria, southern Tunisia, and western Libya. Well logs and lithologic information from more than 500 wells were used to correlate the 30 sequences throughout the basin (total area more than 1 million km{sup 2}). Based on systematic change in the log response of strata in successively younger sequences, five groups of sequences with distinctive characteristics have been identified: Cambro-Ordivician, Upper Silurian-Middle Devonian, Upper Devonian, Carboniferous, and Middle Triassic-Middle Jurassic. Each sequence group is terminated by a major, tectonically enhanced sequence boundary that is immediately overlain (except for the Carboniferous) by a shale-prone interval deposited in response to basin-wide flooding. The four Paleozoic sequence groups were deposited on the Saharan platform, a north facing, clastic-dominated shelf that covered most of North Africa during the Paleozoic. The sequence boundary at the top of the Carboniferous sequence group is one of several Permian-Carboniferous angular unconformities in North Africa related to the Hercynian orogeny. The youngest sequence group (Middle Triassic to Middle Jurassic) is a clastic-evaporite package that onlaps southward onto the top of Paleozoic sequence boundary. The progressive changes from the Cambrian to the Jurassic, in the nature of the Ghadames basin sequences is a reflection of the interplay between basin morphology and tectonics, vegetation, eustasy, climate, and sediment supply.

  11. Evidence for an Upper Palaeozoic North-Palaeotethyan succession in Central Iran: The Siah Godar Complex of Jandaq

    NASA Astrophysics Data System (ADS)

    Berra, Fabrizio; Zanchi, Andrea; Malaspina, Nadia; Javadi, Hamid Reza; Koohpeyma, Meysam; Angiolini, Lucia; Vachard, Daniel; Zanchetta, Stefano

    2014-05-01

    The Upper Palaeozoic successions exposed SW of Jandaq, Central Iran, have been studied in the frame of the DARIUS PROGRAMME. These successions, different from the typical passive margin succession of Gondwanan affinity of the Central Iran block, represent keystones for the reconstruction of the convergence (latest Palaeozoic) and docking (Triassic) of Iran to the margin of Eurasia, despite their original relationships have been modified by Mesozoic to Quaternary tectonics, hampering Palaeozoic palaeogeographic reconstructions. In the Jandaq area, three isolated Upper Palaeozoic outcrops, different for tectonic deformation and lithological composition, are preserved close to amphibolite-facies metamorphic rocks of the Jandaq Complex. The southernmost of these outcrops (Chah Rizab) consists of a succession of volcanics interbedded with severely deformed carbonate layers, Fammenian-Tournaisian in age (Bagheri and Stampfli, 2008) according to conodonts, unconformably covered by conglomerates with volcanic and granitoid blocks. The intermediate outcrop is characterized by deformed massive limestones (Early to Late Carboniferous, Sharkovski et al.; 1984) yielding crinoid ossicles, brachiopods (Choristites aff. C. mosquensis, Orulgania sp.)and bryozoans. They are associated with cherty limestones, fine-grained siliciclastics and bedded limestones rich in isolated corals. Shallow marine sedimentation with local episodes of deeper water facies can be inferred. A lithologically different, poorly deformed succession occurs slightly to the north: it consists of alluvial plain sandstones and conglomerates containing marble, volcanic and sedimentary pebbles, as well as granitoids and granophyres. U-Pb radiometric dating on zircons from these rocks are in progress. In the upper part of the unit, marine ingressions are documented by coastal well-selected quartzarenites and a thin limestone intercalation containing brachiopods (Choristites aff. C. mosquensis, Choristites sp

  12. Long-Billed Curlew Breeding Success on Mid-Columbia River National Wildlife Refuges, South-Central Washington and North-Central Oregon, 2007-08

    USGS Publications Warehouse

    Stocking, Jessica; Elliott-Smith, Elise; Holcomb, Neil; Haig, Susan M.

    2010-01-01

    Long-billed curlew (Numenius americanus) reproductive success was evaluated on the Mid-Columbia River National Wildlife Refuges of south-central Washington and north-central Oregon during the 2007 and 2008 breeding seasons. Additionally, we assisted the U.S. Fish and Wildlife Service in collecting information on distribution, abundance, and brood habitat for this shorebird species of conservation concern. A total of 32 breeding pairs were located on the refuges in 2007 and 35 pairs were located in 2008. We monitored 17 nests in 2007 and 23 nests in 2008. Curlew pairs were most abundant on Hanford Reach National Monument in 2007 but more nests were located on Umatilla National Wildlife Refuge in both years, with Columbia National Wildlife Refuge supporting few pairs. Nest success was 23.6 percent in 2007 and 32.9 percent in 2008 after taking into account exposure time and combining data for all the refuges. We were unable to detect any relationship between nest success and habitat type or habitat variables measured. However, our study was the first to document use of agricultural fields on the refuge as curlew nest habitat. We collected 39 and 28 brood locations in 2007 and 2008, respectively, and many observations were likely resightings of the same brood. Broods used a similar variety of habitats as nesting curlew and no clear habitat use pattern was detected.

  13. Seismic stratigraphy and clay mineral distribution in shallow-marine siliciclastic deposits, central Mississippi sound, North-central Gulf of Mexico

    SciTech Connect

    Harper, G.G.; Manley, F.H.; Staheli, A.C.

    1983-03-01

    Three north-south high-resolution (7 kHz) seismic profiles and 16 20-foot cores taken at shot-point locations in central Mississippi Sound were utilized to determine: (1) any meaningful seismic reflector configurations in the subsurface; (2) the clay species dispersal pattern and its relation to transport systems that move sediment into the depositional basin; (3) any change in clay mineral species that has occurred through time with respect to deposition of 5 to 6 m (16 to 20 ft) of sediment. Interpretation of shallow seismic events (20 m (66 ft)) and clay mineral analysis indicates that extrinsic factors largely determined the clay mineral species and geologic history of Pleistocene and Holocene sedimentation in central Mississippi Sound. Trend surface maps, residual maps, profiles of the smectite (montmorillonite) to kaolinite ratios, and seismic profiles illustrate that: (1) Mississippi Sound has been influenced by transgressions and regressions associated with proglacial and interglacial stages; (2) a toplap seismic reflection configuration forms the probable Pleistocene-Holocene boundary; (3) at least one ancient barrier island is located inside the Holocene barrier system; (4) there is a late date for sea level reaching its present location (2500 years B.P.); (5) the influence of the Mississippi River system on sedimentation is soon after inundation of Mississippi Sound; (6) the longshore currents and flood tides supplied sediment rich in kaolinite to the study area; (7) the drainage systems emptying into the study area have local influence on clay mineral distribution; and (8) the dredging of ship channels affects the clay-mineral distribution within the sediments immediately below the sediment-water interface in central Mississippi Sound.

  14. Ancient to Modern History of the Jemez Lineament of North Central New Mexico

    NASA Astrophysics Data System (ADS)

    Magnani, M.; Miller, K. C.; Levander, A.; Karlstrom, K. E.

    2002-12-01

    The continental lithosphere of the southwestern US was derived from mantle sources and accreted to the proto-North American continent, more specifically the Archean-age Wyoming province, during a succession of island arc collisions between 1.8-1.6 Ga. Many of the assembly structures, that is, the sutures between accreted island arcs and oceanic fragments, have been difficult to identify from surface geology. Likewise the tectonic significance of major lineaments in today's lithosphere remains uncertain. The Jemez Lineament (JL), originally defined as an alignment of Tertiary-Quaternary volcanic centers, is a NE trending zone characterized by active uplift, low seismic velocity in the mantle, and repeated reactivation. It also coincides with the southern edge of a 300 km wide transition zone between the Yavapai (1.8-1.7 Ga) and Mazatzal (1.7-1.6 Ga) Proterozoic provinces. This study presents new deep crustal seismic reflection results across the Jemez Lineament of NM, and the Proterozoic Yavapai-Mazatzal terrane boundary. The crust is strongly reflective from the sedimentary column to its base at ~39-42 km. The seismic data show large-scale structures that we interpret as a Proterozoic bi-vergent orogen that extends for at least 170 km laterally and roots into the mantle at the southern edge of the Jemez lineament. A significant portion of this orogen is a 20km thick, south-vergent, crustal duplex occupying at least 50% of the crust south of the JL. North of the JL the depth migrated seismic images show a set of upper crustal north verging recumbent folds and related thrusts in the Proterozoic rocks as well as a south dipping reflectivity in the lower crust that we interpret as one of the north-verging ramps associated with the orogen. Subhorizontal high amplitude reflections across the JL at about 7-15km depth are interpreted to be extensive magmatic intrusions of uncertain age. Based on the seismic and geologic data, we argue that the JL represents both a

  15. Reduced admixture of North Atlantic Deep Water to the deep central South Pacific during the last two glacial periods

    NASA Astrophysics Data System (ADS)

    Molina-Kescher, Mario; Frank, Martin; Tapia, Raúl; Ronge, Thomas A.; Nürnberg, Dirk; Tiedemann, Ralf

    2016-06-01

    The South Pacific is a sensitive location for the variability of the global oceanic thermohaline circulation given that deep waters from the Atlantic Ocean, the Southern Ocean, and the Pacific Basin are exchanged. Here we reconstruct the deep water circulation of the central South Pacific for the last two glacial cycles (from 240,000 years ago to the Holocene) based on radiogenic neodymium (Nd) and lead (Pb) isotope records complemented by benthic stable carbon data obtained from two sediment cores located on the flanks of the East Pacific Rise. The records show small but consistent glacial/interglacial changes in all three isotopic systems with interglacial average values of -5.8 and 18.757 for ɛNd and 206Pb/204Pb, respectively, whereas glacial averages are -5.3 and 18.744. Comparison of this variability of Circumpolar Deep Water (CDW) to previously published records along the pathway of the global thermohaline circulation is consistent with reduced admixture of North Atlantic Deep Water to CDW during cold stages. The absolute values and amplitudes of the benthic δ13C variations are essentially indistinguishable from other records of the Southern Hemisphere and confirm that the low central South Pacific sedimentation rates did not result in a significant reduction of the amplitude of any of the measured proxies. In addition, the combined detrital Nd and strontium (87Sr/86Sr) isotope signatures imply that Australian and New Zealand dust has remained the principal contributor of lithogenic material to the central South Pacific.

  16. Holocene flood frequency across the Central Alps - solar forcing and evidence for variations in North Atlantic atmospheric circulation

    NASA Astrophysics Data System (ADS)

    Wirth, Stefanie B.; Glur, Lukas; Gilli, Adrian; Anselmetti, Flavio S.

    2013-11-01

    The frequency of large-scale heavy precipitation events in the European Alps is expected to undergo substantial changes with current climate change. Hence, knowledge about the past natural variability of floods caused by heavy precipitation constitutes important input for climate projections. We present a comprehensive Holocene (10,000 years) reconstruction of the flood frequency in the Central European Alps combining 15 lacustrine sediment records. These records provide an extensive catalog of flood deposits, which were generated by flood-induced underflows delivering terrestrial material to the lake floors. The multi-archive approach allows suppressing local weather patterns, such as thunderstorms, from the obtained climate signal. We reconstructed mainly late spring to fall events since ice cover and precipitation in form of snow in winter at high-altitude study sites do inhibit the generation of flood layers. We found that flood frequency was higher during cool periods, coinciding with lows in solar activity. In addition, flood occurrence shows periodicities that are also observed in reconstructions of solar activity from 14C and 10Be records (2500-3000, 900-1200, as well as of about 710, 500, 350, 208 (Suess cycle), 150, 104 and 87 (Gleissberg cycle) years). As atmospheric mechanism, we propose an expansion/shrinking of the Hadley cell with increasing/decreasing air temperature, causing dry/wet conditions in Central Europe during phases of high/low solar activity. Furthermore, differences between the flood patterns from the Northern Alps and the Southern Alps indicate changes in North Atlantic circulation. Enhanced flood occurrence in the South compared to the North suggests a pronounced southward position of the Westerlies and/or blocking over the northern North Atlantic, hence resembling a negative NAO state (most distinct from 4.2 to 2.4 kyr BP and during the Little Ice Age). South-Alpine flood activity therefore provides a qualitative record of variations

  17. Perfluorinated alkyl substances (PFASs) in household dust in Central Europe and North America.

    PubMed

    Karásková, Pavlína; Venier, Marta; Melymuk, Lisa; Bečanová, Jitka; Vojta, Šimon; Prokeš, Roman; Diamond, Miriam L; Klánová, Jana

    2016-09-01

    Concentrations of 20 perfluorinated alkyl substances (PFASs) were measured in dust samples from 41 homes in Canada, the Czech Republic, and United States in the spring-summer of 2013. The most frequently detected compounds were perfluorohexanoic acid (PFHxA) and perfluorooctane sulfonate (PFOS). PFOS and perfluorooctanoic acid (PFOA) had the highest concentrations of PFASs in all countries. PFOS median concentrations for the three countries were between 9.1 and 14.1ng/g, and PFOA medians ranged between 8.2 and 9.3ng/g. In general, concentrations in North America were higher than in the Czech Republic, which is consistent with usage patterns. No differences were found for perfluorooctane sulfonamides/sulfonamidoethanols (FOSA/Es) levels due to the low number of detections. Homologue profiles suggest that the shift from longer to shorter chain PFASs is more advanced in North America than in Europe. Significant relationships were found among individual homologues and between PFAS concentrations in dust and type of floor, number of people living in the house, and building age. PMID:27295048

  18. Climatic variability, fire, and vegetation modeling in the North American Central Grassland Region

    SciTech Connect

    Lenihan, J.M.; Neilson, R.P. )

    1994-06-01

    In developing an equilibrium vegetation model for assessing the sensitivity of natural vegetation to climatic change in the Central Grasslands, we encountered difficulties in establishing solely climatic determinants for grasslands. Under the normal climate, woody plant dominance was predicted for much of the region supporting open grassland at the time of European settlement. Climatic data for historic periods and a fire model were used to test whether grass dominance was promoted by (1) climatic periods distinct from the normal period, (2) by fire, or (3) by the interactive effect of both. Grass/woody ratios in test simulations exhibited spatio-temporal variation produced by complex interactions among PET, precipitation seasonality, competition for soil moisture, and fuel characteristics determining fire intensity. Results support concepts of plant community thresholds and multiple steady states in the Central Grassland region.

  19. Lower Palaeozoic of North-Western and West-Central Africa

    SciTech Connect

    Holland, C.H.

    1985-01-01

    The first compilation in English of the stratigraphy, palaeontology, sedimentology, palaeogeography, and palaeoclimatology of the Lower Palaeozoic found in this area. The fourth volume in the Lower Palaeozoic Rocks of the World Series discusses geological formations such as the lower Cambrian tribolite-bearing sequences of Morocco, those showing evidence of late Ordovician glaciation in West-Central Africa, and the Silurian-Devonian sequences of Morocco and Algeria.

  20. In Situ Assimilation Tracked By Trace Element Variation in Augite: Sausfjellet Pluton, North-Central Norway

    NASA Astrophysics Data System (ADS)

    Barnes, C. G.; Coint, N.; Yoshinobu, A. S.; Prestvik, T.; Barnes, M. A. W.

    2014-12-01

    The Sausfjellet pluton is a sub-circular, 445 Ma pluton in the Bindal Batholith. It was intruded into mid-crustal level (~700 MPa), high-grade rocks during Taconian assembly of the Helgeland Nappe Complex. Stage 1 of the pluton is massive pyroxene hornblende gabbro with poikilitic hornblende. Stage 2, the subject of this study, occupies the central and western parts of the pluton and is gradationally zoned from central, layered, xenolith-rich hornblende biotite two-pyroxene diorite + anorthosite, to western, massive, xenolith-poor hornblende biotite three-pyroxene quartz monzonite. Bulk-rock compositions are consistent with widespread accumulation of pyroxene + plagioclase. In order to separate effects of accumulation from assimilation, trace element zoning profiles in augite were used as a proxy for changes in melt composition. Augite is normally zoned, with incompatible elements increasing from cores to rims. However, trace element variation among samples plots as multiple trends that can be resolved into two broad groups that correspond to the central and western zones. Augite in the layered central zone has lower abundances of REE, Pb and Hf and higher abundances of Cr, V, Ni, Sr, and P compared to the western zone. The two trends intersect at low concentrations of incompatible elements such as Zr. Calculation of melts in equilibrium with augite, combined with AFC-type modeling, suggest that variation in augite Zr contents requires assimilation of Zr-rich rocks in all Stage 2 rocks. In the western zone, increases in Zr, Hf, REE and Pb suggest assimilation of Neoproterozoic gneisses that are host to the western zone; this conclusion is consistent with bulk-rock δ18O values. We conclude that assimilation of host rocks was widespread in this mid-crustal magma body, and that augite preserves a trace element record of differentiation (AFC) that is difficult to identify using bulk-rock compositions alone.

  1. Lithospheric expression of geological units in central and eastern North America from full waveform tomography

    NASA Astrophysics Data System (ADS)

    Yuan, Huaiyu; French, Scott; Cupillard, Paul; Romanowicz, Barbara

    2014-09-01

    The EarthScope TA deployment has provided dense array coverage throughout the continental US and with it, the opportunity for high resolution 3D seismic velocity imaging of both lithosphere and asthenosphere in the continent. Building upon our previous long-period waveform tomographic modeling in North America, we present a higher resolution 3D isotropic and radially anisotropic shear wave velocity model of the North American lithospheric mantle, constructed tomographically using the spectral element method for wavefield computations and waveform data down to 40 s period. The new model exhibits pronounced spatial correlation between lateral variations in seismic velocity and anisotropy and major tectonic units as defined from surface geology. In the center of the continent, the North American craton exhibits uniformly thick lithosphere down to 200-250 km, while major tectonic sutures of Proterozoic age visible in the surface geology extend down to 100-150 km as relatively narrow zones of distinct radial anisotropy, with Vsv>Vsh. Notably, the upper mantle low velocity zone is present everywhere under the craton between 200 and 300 km depth. East of the continental rift margin, the lithosphere is broken up into a series of large, somewhat thinner (150 km) high velocity blocks, which extend laterally 200-300 km offshore into the Atlantic Ocean. Between the craton and these deep-rooted blocks, we find a prominent narrow band of low velocities that roughly follows the southern and eastern Laurentia rift margin and extends into New England. We suggest that the lithosphere along this band of low velocities may be thinned due to the combined effects of repeated rifting processes and northward extension of the hotspot related Bermuda low-velocity channel across the New England region. We propose that the deep rooted high velocity blocks east of the Laurentia margin represent the Proterozoic Gondwanian terranes of pan-African affinity, which were captured during the Rodinia

  2. North Atlantic Oscillation Dynamics Recorded in Central Norwegian Fjord Sediments During the Past 2800 Years

    NASA Astrophysics Data System (ADS)

    Faust, J.; Knies, J.; Fabian, K.; Giraudeau, J.

    2014-12-01

    The North Atlantic Oscillation (NAO) is the leading mode of atmospheric circulation variability in the North Atlantic region. Long-term NAO reconstructions are crucial to better understand NAO variability in its response to climate forcing factors, and assess predictability and possible shifts associated with ongoing global warming. However, existing records are rare and often inconsistent (Pinto and Raible, 2012). Fjord deposits have a great potential for providing high-resolution sedimentary records that reflect local terrestrial and marine processes and, therefore, offer unique opportunities for the investigation of sedimentological and geochemical climatically induced processes. Recently, Faust et al. (2014) provided a comprehensive overview of the Trondheimsfjord environmental system by applying a geochemical multiproxy analysis on surface sediment samples and compared his findings with available geochemical data from the fjords drainage area. Here we use the gained knowledge to establish the first high resolution NAO proxy record from marine sediments. By comparing geochemical measurements from a short sediment core with instrumental data we show that marine primary productivity proxies are sensitive to NAO changes during the past 50 years. This result is used to link a 2,800 years paleoproductivity record to a 500-year long winter NAO reconstruction based on early instrumental and documentary proxy data. We find that NAO variabilities coincide with climatically associated paleo-demographic trends and persistent positive/negative NAO phases are in accordance with cooler/warmer climate periods, such as Medieval Climate Anomaly and Little Ice Age. Moreover, negative NAO phases coincide with northern hemisphere glacier advances and rapid phase transitions related to large volcanic eruptions indicate the existence of internal atmospheric thresholds and instabilities in the atmospheric circulation pattern. Faust J.C., Knies J., Slagstad T., Vogt C., Milzer G. and

  3. U-Pb Geochronologic Evidence for the Evolution of the Gondwanan Margin of the North- Central Andes

    NASA Astrophysics Data System (ADS)

    Chew, D.; Schaltegger, U.; Košler, J.; Whitehouse, M.; Gutjahr, M.; Spikings, R.; Miškovic, A.

    2007-05-01

    The Neoproterozoic - Early Paleozoic evolution of the Gondwanan margin of the north-central Andes has been investigated by a U-Pb zircon geochronology study in the Eastern Cordilleras of Peru and Ecuador, combining LA- ICPMS detrital zircon analysis with dating of syn- and post-tectonic intrusives by TIMS and ion microprobe. The majority of detrital zircon samples exhibit prominent peaks in the ranges 0.45 - 0.65 Ga and 0.9 - 1.3 Ga, with minimal older detritus from the Amazonian craton. The detrital zircon data demonstrate that the basement to the western Gondwanan margin was likely composed of a metamorphic belt of Grenvillian age, upon which an Early Paleozoic magmatic belt was situated in a similar way to the Sierra Pampeanas and Famatina Terranes of northern Argentina. These two orogenic belts are interpreted to be either buried underneath the present-day Andean chain or adjacent foreland sediments. Plutons associated with the Early Paleozoic subduction-related magmatic belt have been identified in the Eastern Cordillera of Peru, and have been dated by U-Pb zircon TIMS and ion microprobe to 474 - 442 Ma. This is in close agreement with the ages of subduction-related magmatism in the Arequipa - Antofalla Basement (e.g. Loewy et al., 2004). This Early Paleozoic arc is clearly not linear as it jumps from a coastal location in the Arequipa - Antofalla Basement to several hundred kilometers inland in the Eastern Cordillera further to the north. This is interpreted as an embayment on the Proto-Andean margin at the time the arc was initiated; if this is the case the northern termination of the Arequipa-Antofalla Basement in the vicinity of Lima is an Ordovician or older feature. The arc magmatism pre- and post dates phases of regional metamorphism in the Eastern Cordillera of Peru. U- Pb zircon ion microprobe dating of zircon overgrowths in high-grade leucosomes demonstrates that the presence of a metamorphic event at c. 478 Ma, and refutes the previously

  4. Database compilation for the geologic map of the San Francisco volcanic field, north-central Arizona

    USGS Publications Warehouse

    Bard, Joseph A.; Ramsey, David W.; Wolfe, Edward W.; Ulrich, George E.; Newhall, Christopher G.; Moore, Richard B.; Bailey, Norman G.; Holm, Richard F.

    2015-01-01

    The orignial geologic maps were prepared under the Geothermal Research Program of the U.S. Geological Survey as a basis for interpreting the history of magmatic activity in the volcanic field. The San Francisco field, which is largely Pleistocene in age, is in northern Arizona, just north of the broad transition zone between the Colorado Plateau and the Basin and Range province. It is one of several dominantly basaltic volcanic fields of the late Cenozoic age situated near the margin of the Colorado Plateau. The volcanic field contains rocks ranging in composition from basalt to rhyolite—the products of eruption through Precambrian basement rocks and approximately a kilometer of overlying, nearly horizontal, Paleozoic and Mesozoic sedimentary rocks. About 500 km3 of erupted rocks cover about 5,000 km2 of predominantly Permian and locally preserved Triassic sedimentary rocks that form the erosionally stripped surface of the Colorado Plateau in Northern Arizona.

  5. Preliminary Results From the CAUGHT Experiment: Investigation of the North Central Andes Subsurface Using Receiver Functions and Ambient Noise Tomography

    NASA Astrophysics Data System (ADS)

    Ryan, J. C.; Ward, K. M.; Porter, R. C.; Beck, S. L.; Zandt, G.; Wagner, L. S.; Minaya, E.; Tavera, H.

    2011-12-01

    Jamie Ryan, Kevin M. Ward, Ryan Porter, Susan Beck, George Zandt, Lara Wagner, Estela Minaya, and Hernando Tavera The University of Arizona The University of North Carolina San Calixto Observatorio, La Paz, Bolivia IGP, Lima, Peru In order to investigate the interplay between crustal shortening, lithospheric removal, and surface uplift we have deployed 50 broadband seismometers in northwestern Bolivia and southern Peru as part of the interdisciplinary Central Andean Uplift and Geodynamics of High Topography (CAUGHT) project. The morphotectonic units of the central Andes from west to east, consist of the Western Cordillera, the active volcanic arc, the Altiplano, an internally drained basin (~4 km elevation), the Eastern Cordillera, the high peaks (~6 km elevation) of an older fold and thrust belt, the Subandean zone, the lower elevation active fold and thrust belt, and the foreland Beni basin. Between northwestern Bolivia and southern Peru, the Altiplano pinches out north of Lake Titicaca as the Andes narrow northward. The CAUGHT seismic instruments were deployed between 13° to 18° S latitudes to investigate the crust and mantle lithosphere of the central Andes in this transitional zone. In northwest Bolivia, perpendicular to the strike of the Andes, there is a total of 275 km of documented upper crustal shortening (15° to 17°S) (McQuarrie et al, 2008). Associated with the shortening is crustal thickening and possibly lithospheric removal as the thickening lithospheric root becomes unstable. An important first order study is to compare upper crustal shortening estimates with present day crustal thickness. To estimate crustal thickness, we have calculated receiver functions using an iterative deconvolution method and used common conversion point stacking along the same profile as the geologically based shortening estimates. In our preliminary results, we observed a strong P to S conversion corresponding to the Moho at approximately 60-65 km depth underneath the

  6. Geologic reconnaissance of an extensive clay unit in north-central Suffolk County, Long Island, New York

    USGS Publications Warehouse

    Krulikas, R.K.; Koszalka, E.J.

    1983-01-01

    Recent geologic data indicate an extensive lacustrine clay unit within the glacial deposits in the area between the Harbor Hill and Ronkonkoma moraines in north-central Suffolk County, New York. The unit, locally known as the ' Smithtown clay unit ' (informal usage), is an integral part of the glacial aquifer in this area. The clay occurs at depths varying from 90 ft above to 150 ft below National Geodetic Vertical Datum of 1929 (NGVD) and attains a maximum thickness of 170 ft in the northern part of the Town of Smithtown. Its upper surface is mostly above NGVD and reaches a maximum altitude of 90 ft in the Town of Huntington. The unit is predominantly clay but locally contains lenses of sand, silt, and gravel. The upper part of the clay is generally light to dark brown; the lower part is light gray, which is characteristics of other clays in the glacial aquifer. (USGS)

  7. The Central China North-South Seismic Belt: Seismicity, Ergodicity, and Five-year PI Forecast in Testing

    NASA Astrophysics Data System (ADS)

    Zhang, Shengfeng; Wu, Zhongliang; Jiang, Changsheng

    2016-01-01

    Instrumentally recorded seismicity from 1970/01/01 to 2014/01/01 of the central China north-south seismic belt (21.0°-41.5°N, 97.5°-107.5°E) was analyzed, emphasizing the applicability of the predictive algorithms based on the assumptions of meta-stable equilibrium. The seismicity in this region was shown to exhibit ergodicity from 1980 to the present, with sub-region dependence, and interrupted by the 2008 Wenchuan earthquake. pattern informatics algorithm, a statistical physics-based predictive model for five-year time scale, is put to forward forecast test for the period 2014/01/01 to 2019/01/01.

  8. Evaluation of multiband, multitemporal, and transformed LANDSAT MSS data for land cover area estimation. [North Central Missouri

    NASA Technical Reports Server (NTRS)

    Stoner, E. R.; May, G. A.; Kalcic, M. T. (Principal Investigator)

    1981-01-01

    Sample segments of ground-verified land cover data collected in conjunction with the USDA/ESS June Enumerative Survey were merged with LANDSAT data and served as a focus for unsupervised spectral class development and accuracy assessment. Multitemporal data sets were created from single-date LANDSAT MSS acquisitions from a nominal scene covering an eleven-county area in north central Missouri. Classification accuracies for the four land cover types predominant in the test site showed significant improvement in going from unitemporal to multitemporal data sets. Transformed LANDSAT data sets did not significantly improve classification accuracies. Regression estimators yielded mixed results for different land covers. Misregistration of two LANDSAT data sets by as much and one half pixels did not significantly alter overall classification accuracies. Existing algorithms for scene-to scene overlay proved adequate for multitemporal data analysis as long as statistical class development and accuracy assessment were restricted to field interior pixels.

  9. GOES-derived fog and low cloud indices for coastal north and central California ecological analyses

    NASA Astrophysics Data System (ADS)

    Torregrosa, Alicia; Combs, Cindy; Peters, Jeff

    2016-02-01

    Fog and low cloud cover (FLCC) strongly influences the water, energy, and nutrient flux of coastal ecosystems. Easy-to-use FLCC data are needed to quantify the impacts of FLCC on ecosystem dynamics especially during hot and dry Mediterranean climate summers. Monthly, annual, and decadal FLCC digital maps (indices) were derived for June-September 1999-2009 for coastal California, latitude 34.50°N (south of Monterey Bay) to latitude 41.95°N (north of Crescent City) from 26,000 hourly night and day Geostationary Operational Environmental Satellite (GOES) images. Monthly average FLCC ranges from <2 to 18 hours per day (h/d). Average FLCC over the ocean increases from north (9 h/d) to south (14 h/d), whereas on land, FLCC is highest where land juts into the prevailing NW winds and is lowest in the lee of major capes. FLCC advects farthest inland through low-lying NW ocean-facing valleys. At night, average total hours of FLCC are higher more frequently on land than over the ocean. The interannual FLCC coefficient of variation shows long-term geographic stability that is strongly associated with landform position. FLCC hours per day mapped contours, derived from decadal average FLCC, delineate the commonly used term "fog belt" into FLCC zones with increased locational precision. FLCC indices are available for download from the California Landscape Conservation Cooperative Climate Commons website (http://climate.calcommons.org/datasets/summertime-fog). FLCC indices can improve analyses of biogeographic and bioclimatic species distribution models; understanding meteorological mechanisms driving FLCC patterns; solar energy feasibility studies; investigations of ecohydrology, evapotranspiration, and agricultural irrigation demand; and viticulture ripening models.

  10. GOES-derived fog and low cloud indices for coastal north and central California ecological analyses

    USGS Publications Warehouse

    Torregrosa, Alicia; Cindy Combs; Peters, Jeff

    2015-01-01

    Fog and low cloud cover (FLCC) changes the water, energy, and nutrient flux of coastal ecosystems. Easy-to-use FLCC data are needed to quantify the impacts of FLC on ecosystem dynamics during hot, dry Mediterranean climate summers. FLCC indices were generated from 26,000 hourly night and day FLCC maps derived from Geostationary Environmental Operational Satellite (GOES) data for June, July, August, and September, 1999- 2009 for coastal California, latitude 34.50°N, south of Monterey Bay, to latitude 41.95°N, north of Crescent City. Monthly FLCC average hours per day (h/d) range from < 2 to 18. Average FLCC over the ocean increases from north (9 h/d) to south (14 h/d) whereas FLCC over land is reversed. Over land, FLCC is highest where land juts into the prevailing NW winds and is lowest in the lee of major capes. FLCC advects furthest inland through low-lying NW ocean-facing valleys. At night hours of FLCC is higher more frequently on land than over the ocean. Interannual FLCC coefficient of variation shows long term geographic stability strongly associated with landform position. Contours delineating homogeneous zones of FLCC, derived from average decadal h/d FLCC, provide data to refine the commonly used term ‘fog belt.’ FLCC indices are available for download from the California Landscape Conservation Cooperative Climate Commons website. FLCC indices can be used to improve analyses of biogeographic and bioclimatic species distribution models, meteorological mechanisms driving FLCC patterns, ecohydrological investigations of evapotranspiration, solar energy feasibility studies, agricultural irrigation demand and viticultural ripening models.

  11. Significance of tourmaline-rich rocks in the north range group of the cuyuna iron range, East-Central Minnesota

    USGS Publications Warehouse

    Cleland, J.M.; Morey, G.B.; McSwiggen, P.L.

    1996-01-01

    Concentrations of tourmaline in Early Proterozoic metasedirnentary rocks of the Cuyuna iron range, east-central Minnesota, provide a basis for redefinition of the evolutionary history of the area. Manganiferous iron ore forms beds within the Early Proterozoic Trommald Formation, between thick-bedded granular iron-formation having shallow-water depositional attributes and thin-bedded, nongranular iron-formation having deeper water attributes. These manganese-rich units were previously assumed to be sedimentary in origin. However, a revaluation of drill core and mine samples from the Cuyuna North range has identified strata-bound tourmaline and tourmalinite, which has led to a rethinking of genetic models for the geology of the North range. We interpret the tourmaline-rich rocks of the area to be a product of submarine-hydrothermal solutions flowing along and beneath the sedirnent-seawater interface. This model for the depositional environment of the tourmaline is supported by previously reported mineral assemblages within the Trommald Formation that comprise aegirine; barium feldspar; manganese silicates, carbonates, and oxides; and Sr-rich barite veins. In many places, tourmaline-rich metasedimentary rocks and tourmalinites are associated locally with strata-bound sulfide deposits. At those localities, the tourmaline-rich strata are thought to be lateral equivalents of exhalative sulfide zones or genetically related subsea-floor replacements. On the basis of the occurrence of the tourmaline-rich rocks and tourmalinites, and on the associated minerals, we suggest that there is a previously unrecognized potential for sediment-hosted sulfide deposits in the Cuyuna North range.

  12. Water resources of the Rattlesnake Butte area, a site of potential lignite mining in west-central North Dakota

    USGS Publications Warehouse

    Horak, W.F.

    1983-01-01

    The D and E lignite beds, the two mineable beds in the lower Sentinel Butte Member (Fort Union Formation), underlies the entire Rattlesnake Butt study area, North Dakota but are unsaturated over much of their area of occurrence. Ground-water flow in both lignite aquifers is largely controlled by topography. Interconnected sand beds form aquifers between the E and D beds (E-D aquifer) and below the D bed (D-HT aquifer). Both aquifers underlie the central part of the study area and consist of fine silty sand. Depth to the aquifers is as much as 320 feet. Aquifers also occur in strata of Late Cretaceous and early Tertiary age. Aquifers in the Fox Hills Sandstone (Cretaceous) and lower Tongue River Member (Tertiary) lie at depths of about 1,700 and 750 feet, respectively. All aquifers yield a sodium bicarbonate or sodium sulfate type water. Mean dissolved-solids concentrations in the four shallowest aquifers ranged from 1,290 to 1,970 milligrams per litter. North Creek and an unnamed tributary of Green River drain most of the study area. North Creek, the major drain, ceases to flow during several months of most years, while the Green River tributary, with a smaller basin area, has sustained base flows of 0.15 to 0.25 cubic foot per second. Mining-induced impacts on the shallow ground-water flow system would be very localized because of the already low water levels and the segmented nature of the flow system in the lignite aquifers. (USGS)

  13. Potentiometric surface, 2012, and water-level differences, 2005-12, of the Sparta Aquifer in north-central Louisiana

    USGS Publications Warehouse

    McGee, Benton D.; Brantly, Jeffrey A.

    2015-01-01

    The Sparta aquifer is used in 15 parishes in north-central Louisiana, primarily for public supply and industrial purposes. Of those parishes, eight (Bienville, Claiborne, Jackson, Lincoln, Ouachita, Union, Webster, and Winn) rely on the Sparta aquifer as their principal source of groundwater. In 2010, withdrawals from the Sparta aquifer in Louisiana totaled 63.11 million gallons per day (Mgal/d), a reduction of more than 11 percent from 1995, when the highest rate of withdrawals (71.32 Mgal/d) from the Sparta aquifer were documented. The Sparta aquifer provides water for a variety of purposes which include public supply (34.61 Mgal/d), industrial (25.60 Mgal/d), rural domestic (1.50 Mgal/d), and various agricultural (1.40 Mgal/d). Of the 13 major aquifers or aquifer systems in Louisiana, the Sparta aquifer is currently (2012) the sixth most heavily pumped. The Sparta aquifer is the second most heavily pumped aquifer in Arkansas, which borders Louisiana to the north. In 2005, 170 Mgal/d were withdrawn from the Sparta aquifer in eastern and southern Arkansas; of that total, about 15.55 Mgal/d were withdrawn from the aquifer in Union County, which borders Claiborne and Union Parishes to the north. By 1997, a large cone of depression (a cone-shaped depression in the potentiometric surface caused by and centered on a pumping well or wells) in the Sparta aquifer centered over Union County had merged with the cone of depression at West Monroe. In 2004, the rate of withdrawal from the Sparta aquifer in Union County began to decline and water levels in the aquifer began to rise in nearby areas of Arkansas and Louisiana.

  14. Current and Future Niche of North and Central American Sand Flies (Diptera: Psychodidae) in Climate Change Scenarios

    PubMed Central

    Moo-Llanes, David; Ibarra-Cerdeña, Carlos N.; Rebollar-Téllez, Eduardo A.; Ibáñez-Bernal, Sergio; González, Camila; Ramsey, Janine M.

    2013-01-01

    Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases. PMID:24069478

  15. Influence of Pacific Ocean multidecadal variability on the distributional properties of hydrological variables in north-central Chile

    NASA Astrophysics Data System (ADS)

    Núñez, J.; Rivera, D.; Oyarzún, R.; Arumí, J. L.

    2013-09-01

    This paper addresses the relationship between multitemporal variability and regime shifts in the Pacific Decadal Oscillation and El Niño Southern Oscillation, with precipitation and streamflows in Andean watersheds of the north-central region of Chile. In addition, an analysis of the effect of a regime shift displayed by annual streamflow records on their distributional properties is performed. By applying empirical fluctuation processes to monthly standardized PDO, Niño 3.4, precipitation and streamflow time series, the occurrence of a regime shift in the streamflow series, consistent with that for PDO, but highly dependent on the latitude of particular watersheds, is shown. No regime shift is detected for the precipitation time series. Using the ensemble Empirical Mode Decomposition procedure on all series, a relationship between climatic indices and hydrological variables in two main modes is determined: the former associated with a mean period of quasi 1.5-3 years related to interannual variability, and the latter with a mean period of quasi 30-35 years, related to decadal low frequency variability. Using the regional frequency analysis based on the L-moments procedure, it is found that the distributional properties of streamflow records are influenced by the phases of the PDO, with changes that affect the mean, L-CV, L-skewness and L-kurtosis in three identified homogeneous regions. The importance of incorporating low-frequency climate variability for distributional analysis and the implications of these results for water resources management and planning in north-central Chile and similar areas is discussed.

  16. Paleoecology of an early Holocene faunal and floral assemblage from the Dows Local Biota of north-central Iowa

    NASA Astrophysics Data System (ADS)

    Hudak, Curtis M.

    1984-05-01

    The faunas and floras from the Dows Local Biota provide an opportunity to compare Holocene taxa without a cultural bias. The Dows Local Biota is located in a large depression on the back side (north) of the Altamont I Moraine complex within the Des Moines Lobe. The Dows Silt Fauna/Flora ( = DSF; ca. 9380 ± 130 yr B.P.), one horizon of the Dows Local Biota, was collected for plant macrofossils, mollusks, and micromammals. DSF terrestrial gastropods are upland mesic forest dwellers although one species, Strobilops affinis, is characteristic of more xeric forests and may represent open woods. The aquatic gastropods reflect both permanent and periodic waters. DSF micromammals prefer an open, mesic, deciduous forest. The micromammal sympatry is restricted to a small area within the tension zone and deciduous forest belt of west-central Wisconsin. DSF plants are characteristic of upland forests, moist meadowlands or disturbed areas, and aquatic habitats. The DSF plant sympatry is large but restricted to the conifer-hardwood and deciduous forests along the Great Lakes-New England regions. Quantitative climatic data for the combined DSF sympatries suggest that Dows (ca. 9380 yr B.P.) was cooler than at present, and is nearly identical to that achieved by pollen analyses at the Cherokee Sewer-Lake West Okoboji sites (ca. 9000 yr B.P.) in northwest Iowa. Based on common habitat interpretations and sympatries, about 9380 yr B.P. north-central Iowa was cooler and moister than at present and was occupied by an open deciduous forest.

  17. Little ice age evidence from a south-central North American ice core, U.S.A.

    SciTech Connect

    Naftz, D.L.; Klusman, R.W.; Michel, R.L.

    1996-02-01

    In the past, ice-core records from mid-latitude glaciers in alpine areas of the continental United States were considered to be poor candidates for paleoclimate records because of the influence of meltwater on isotopic stratigraphy. To evaluate the existence of reliable paleoclimatic records, a 160-m ice core, containing about 250 yr of record was obtained from Upper Fremont Glacier, at an altitude of 4000 m in the Wind River Range of south-central North America. The {gamma}{sup 18}O (SMOW) profile from the core shows a -0.95{per_thousand} shift to lighter values in the interval from 101.8 to 150 m below the surface, corresponding to the latter part of the Little Ice Age (LIA). Numerous high-amplitude oscillations in the section of the core from 101.8 to 150 m cannot be explained by site-specific lateral variability and probably reflect increased seasonality or better preservation of annual signals as a result of prolonged cooler temperatures that existed in this alpine setting. An abrupt decrease in these large amplitude oscillations at the 101.8-m depth suggests a sudden termination of this period of lower temperatures which generally coincides with the termination of the LIA. Three common features in the {gamma}{sup 18}O profiles between Upper Fremont Glacier and the better dated Quelccaya Ice Cap cores indicate a global paleoclimate linkage, further supporting the first documented occurrence of the LIA in an ice-core record from a temperate glacier in south-central North America.

  18. Slip rate and earthquake recurrence along the central Septentrional fault, North American-Caribbean plate boundary, Dominican Republic

    USGS Publications Warehouse

    Prentice, C.S.; Mann, P.; Pena, L.R.; Burr, G.

    2003-01-01

    The Septentrional fault zone (SFZ) is the major North American-Caribbean, strike-slip, plate boundary fault at the longitude of eastern Hispaniola. The SFZ traverses the densely populated Cibao Valley of the Dominican Republic, forming a prominent scarp in alluvium. Our studies at four sites along the central SFZ are aimed at quantifying the late Quaternary behavior of this structure to better understand the seismic hazard it represents for the northeastern Caribbean. Our investigations of excavations at sites near Rio Cenovi show that the most recent ground-rupturing earthquake along this fault in the north central Dominican Republic occurred between A.D. 1040 and A.D. 1230, and involved a minimum of ???4 m of left-lateral slip and 2.3 m of normal dip slip at that site. Our studies of offset stream terraces at two locations, Rio Juan Lopez and Rio Licey, provide late Holocene slip rate estimates of 6-9 mm/yr and a maximum of 11-12 mm/yr, respectively, across the Septentrional fault. Combining these results gives a best estimate of 6-12 mm/yr for the slip rate across the SFZ. Three excavations, two near Tenares and one at the Rio Licey site, yielded evidence for the occurrence of earlier prehistoric earthquakes. Dates of strata associated with the penultimate event suggest that it occurred post-A.D. 30, giving a recurrence interval of 800-1200 years. These studies indicate that the SFZ has likely accumulated elastic strain sufficient to generate a major earthquake during the more than 800 years since it last slipped and should be considered likely to produce a destructive future earthquake.

  19. Evaluating Religious Influences on the Utilization of Maternal Health Services among Muslim and Christian Women in North-Central Nigeria

    PubMed Central

    Al-Mujtaba, Maryam; Cornelius, Llewellyn J.; Galadanci, Hadiza; Erekaha, Salome; Okundaye, Joshua N.; Adeyemi, Olusegun A.; Sam-Agudu, Nadia A.

    2016-01-01

    Introduction. Uptake of antenatal services is low in Nigeria; however, indicators in the Christian-dominated South have been better than in the Muslim-dominated North. This study evaluated religious influences on utilization of general and HIV-related maternal health services among women in rural and periurban North-Central Nigeria. Materials and Methods. Targeted participants were HIV-positive, pregnant, or of reproductive age in the Federal Capital Territory and Nasarawa. Themes explored were utilization of facility-based services, provider gender preferences, and Mentor Mother acceptability. Thematic and content approaches were applied to manual data analysis. Results. Sixty-eight (68) women were recruited, 72% Christian and 28% Muslim. There were no significant religious influences identified among barriers to maternal service uptake. All participants stated preference for facility-based services. Uptake limitations were mainly distance from clinic and socioeconomic dependence on male partners rather than religious restrictions. Neither Muslim nor Christian women had provider gender preferences; competence and positive attitude were more important. All women found Mentor Mothers highly acceptable. Conclusion. Barriers to uptake of maternal health services appear to be minimally influenced by religion. ANC/PMTCT uptake interventions should target male partner buy-in and support, healthcare provider training to improve attitudes, and Mentor Mother program strengthening and impact assessment. PMID:27006944

  20. Dynamics of Late Quaternary North African humid periods documented in the clay mineral record of central Aegean Sea sediments

    NASA Astrophysics Data System (ADS)

    Ehrmann, Werner; Seidel, Martin; Schmiedl, Gerhard

    2013-08-01

    The ratio between the clay minerals kaolinite and chlorite has been investigated in high resolution in a late Quaternary sediment core from the central Aegean Sea. The record spans the last ca. 105 ka. The kaolinite/chlorite ratio was used to reconstruct the fine-grained aeolian dust influx from the North African deserts, mainly derived from desiccated lake depressions. It therewith can be used as a proxy for wind activity, aridity and vegetation cover in the source area. The data document three major humid phases in North Africa bracketing the formation of sapropel layers S4, S3 and S1. They occur at > 105-95 ka, 83.5-72 ka and 14-2 ka. The first two phases are characterised by relatively abrupt lower and upper boundaries suggesting a non-linear response of vegetation to precipitation, with critical hydrological thresholds. In contrast, the onset and termination of the last humid period were more gradual. Highest kaolinite/chlorite ratios indicating strongest aeolian transport and aridity occur during Marine Isotope Stage (MIS) 5b, at ca. 95-84 ka. The long-term decrease in kaolinite/chlorite ratios during the last glacial period indicates a gradual decline of deflatable lake sediments in the source areas.

  1. Sero-epizootiological investigation of infectious laryngotracheitis infection in commercial poultry of Plateau State, north central Nigeria.

    PubMed

    Shittu, Ismaila; Sulaiman, Lanre K; Gado, Dorcas A; Egbuji, Anthony N; Ndahi, Mwapu D; Pam, Ezekiel; Joannis, Tony M

    2016-01-01

    Infectious laryngotracheitis (ILT) is a highly contagious acute respiratory disease of chickens with outbreaks resulting in high economic losses due to increased mortality and drop in egg production. This study reports a survey of ILT virus antibody conducted in nine local government areas (LGAs) of Plateau State involving 67 randomly selected commercial poultry flocks. In all, 938 sera were tested using the Agar Gel Immuno-diffusion (AGID) technique. Overall prevalence of 1.2% (N = 11) was recorded. ILT virus antibody was found in 2.5% (n = 9) and 7.1% (n = 2) of the tested sera from Jos South and Langtang North LGAs, respectively. No detectable ILT virus antibody was found from the other seven LGAs. This is the first report of ILT infection in poultry from the North central part of Nigeria. It is therefore recommended that the economic implication of ILT infection in Nigerian poultry population be conducted in order to know if vaccination should be adopted for control. PMID:26918306

  2. Structure of the Cordillera de la Costa Belt, North-Central Venezuela: Implications for plate tectronic models

    SciTech Connect

    Ave Lallemant, H.G.; Sisson, V.B.; Wright, J.E. )

    1993-02-01

    Preliminary results of an on-going study of the Cordillera de la Costa belt between Puerto Cabello and Choroni, north-central Venezuela, indicate that the deformational history is far more complicated than expected from simple plate-tectonic models. The Cordillera de la Costa belt consists of oceanic rocks (e.g., serpentinites, amphibilites, with lenses of eclogite and blueschist) intimately intermixed with metamorphosed continental margin deposits (e.g., mica and graphite schist, quartzite, marble). Locally, large granitic (basement ) complexes of Lower Paleozoic age are included as well. In late Cretaceous time, the entire belt was involved in four synmetamorphic deformations phases (D[sub 1a] to D[sub 1d]); the first (D[sub 1a]) occurred at depths of at 35-40 km and the later ones at successively shallower depths. This deformation occurred in a subduction zone, related to right-oblique convergence of the Farallon and Atlantic plates. The most penetrative structures resulted from (all in present coordinates) north-south contraction and east-west dextral simple shear (D[sub 1b]). During an Early Tertiary ( ) event (D[sub 2]), the belt was emplaced southward onto the South American continental margin. Subsequent deformational structures (D[sub 3]) resulted in cross folds and faults (with small pull-apart basins) which are consistent with the eastward passage of the Caribbean past the South American plate.

  3. A link between North Atlantic cooling and dry events in the core SW monsoon region in Lonar Lake, central India

    NASA Astrophysics Data System (ADS)

    Menzel, Philip; Gaye, Birgit; Prasad, Sushma; Plessen, Birgit; Stebich, Martina; Anoop, Ambili; Riedel, Nils; Basavaiah, Nathani

    2014-05-01

    A sediment core from Lonar Lake in central India covers the complete Holocene and was used to reconstruct the monsoon history of the core SW-monsoon region. We compare C/N ratios, stable carbon and nitrogen isotopes, grain size, as well as amino acid derived degradation proxies with climatically sensitive proxies of other records from South Asia and the North Atlantic region. The comparison reveals some more or less contemporaneous climate shifts. At Lonar Lake, a general long term climate transition from wet conditions during the early Holocene to drier conditions during the late Holocene, delineating the insolation curve, can be reconstructed. Several phases of shorter term climate alteration that superimpose the general climate trend correlate with cold phases in the North Atlantic region. The most pronounced climate deteriorations indicated by our data occurred between 6.2 - 5.2, 4.65 - 3.9, and 2.05 - 0.55 cal ka BP. The strong dry phase between 4.65 - 3.9 cal ka BP at Lonar Lake corroborates the hypothesis that severe climate deterioration contributed to the decline of the Indus Civilisation about 3.9 ka BP.

  4. Evaluating Religious Influences on the Utilization of Maternal Health Services among Muslim and Christian Women in North-Central Nigeria.

    PubMed

    Al-Mujtaba, Maryam; Cornelius, Llewellyn J; Galadanci, Hadiza; Erekaha, Salome; Okundaye, Joshua N; Adeyemi, Olusegun A; Sam-Agudu, Nadia A

    2016-01-01

    Introduction. Uptake of antenatal services is low in Nigeria; however, indicators in the Christian-dominated South have been better than in the Muslim-dominated North. This study evaluated religious influences on utilization of general and HIV-related maternal health services among women in rural and periurban North-Central Nigeria. Materials and Methods. Targeted participants were HIV-positive, pregnant, or of reproductive age in the Federal Capital Territory and Nasarawa. Themes explored were utilization of facility-based services, provider gender preferences, and Mentor Mother acceptability. Thematic and content approaches were applied to manual data analysis. Results. Sixty-eight (68) women were recruited, 72% Christian and 28% Muslim. There were no significant religious influences identified among barriers to maternal service uptake. All participants stated preference for facility-based services. Uptake limitations were mainly distance from clinic and socioeconomic dependence on male partners rather than religious restrictions. Neither Muslim nor Christian women had provider gender preferences; competence and positive attitude were more important. All women found Mentor Mothers highly acceptable. Conclusion. Barriers to uptake of maternal health services appear to be minimally influenced by religion. ANC/PMTCT uptake interventions should target male partner buy-in and support, healthcare provider training to improve attitudes, and Mentor Mother program strengthening and impact assessment. PMID:27006944

  5. Lg excitation, attenuation, and source spectral scaling in central and eastern North America

    SciTech Connect

    Mitchell, B.J.; Xie, J.; Baqer, S.

    1997-10-01

    Seismic moments and corner frequencies were obtained for many earthquakes in the central and eastern United States, and for a few events in the western United States, using the Lg phase and a recently developed inversion algorithm. Additionally, Q values for the Lg phase along paths to individual stations were obtained simultaneously with the source parameters. Both corner frequencies and magnitudes were found to vary systematically with moment. For moments between 0.15 and 400 x 10{sup 15} N-m corner frequencies vary between about 4 and 0.2 Hz while body-wave magnitude varies between about 3.5 and 5.8. A map of Lg Q values displays a systematic decrease from east and west. Maximum and minimum values are 989 and 160, respectively. Lg coda Q values were obtained for the entire United States with excellent coverage in the eastern and western portions of the country and somewhat poorer coverage in the central portion. Lg coda Q is highest (700-750) in a region of the northeastern United States that includes portions of New York and Pennsylvania and lowest (>200) in California. Lg coda Q is lower (250-450) everywhere west of Rocky Mountains than in the rest of the country (450-750). Q determinations for both the direct Lg phase and Lg coda indicate that, for an earthquake of a given magnitude, Lg and its coda will propagate much more efficiently, and cause damage over a wider area, in the eastern and central United States than it will in the United States.

  6. Characterization of the radon source in North-Central Florida. Final report part 1 -- Final project report; Final report part 2 -- Technical report

    SciTech Connect

    1997-12-01

    This report contains two separate parts: Characterization of the Radon Source in North-Central Florida (final report part 1 -- final project report); and Characterization of the Radon Source in North-Central Florida (technical report). The objectives were to characterize the radon 222 source in a region having a demonstrated elevated indoor radon potential and having geology, lithology, and climate that are different from those in other regions of the U.S. where radon is being studied. Radon availability and transport in this region were described. Approaches for predicting the radon potential of lands in this region were developed.

  7. The Radiative Role of Free Tropospheric Aerosols and Marine Clouds over the Central North Atlantic

    SciTech Connect

    Mazzoleni, Claudio; Kumar, Sumit; Wright, Kendra; Kramer, Louisa; Mazzoleni, Lynn; Owen, Robert; Helmig, Detlev

    2014-12-09

    The scientific scope of the project was to exploit the unique location of the Pico Mountain Observatory (PMO) located in the summit caldera of the Pico Volcano in Pico Island in the Azores, for atmospheric studies. The observatory, located at 2225m a.s.l., typically samples free tropospheric aerosols laying above the marine low-level clouds and long-range transported from North America. The broad purpose of this research was to provide the scientific community with a better understanding of fundamental physical processes governing the effects of aerosols on radiative forcing and climate; with the ultimate goal of improving our abilities to understand past climate and to predict future changes through numerical models. The project was 'exploratory' in nature, with the plan to demonstrate the feasibility of deploying for the first time, an extensive aerosol research package at PMO. One of the primary activities was to test the deployment of these instruments at the site, to collect data during the 2012 summer season, and to further develop the infrastructure and the knowledge for performing novel research at PMO in follow-up longer-term aerosol-cloud studies. In the future, PMO could provide an elevated research outpost to support the renewed DOE effort in the Azores that was intensified in 2013 with the opening of the new sea-level ARM-DOE Eastern North Atlantic permanent facility at Graciosa Island. During the project period, extensive new data sets were collected for the planned 2012 season. Thanks to other synergistic activities and opportunities, data collection was then successfully extended to 2013 and 2014. Highlights of the scientific findings during this project include: a) biomass burning contribute significantly to the aerosol loading in the North Atlantic free troposphere; however, long-range transported black carbon concentrations decreased substantially in the last decade. b) Single black carbon particles – analyzed off-line at the electron

  8. Shoreline erosion rates along barrier islands of the north central gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Shabica, Stephen V.; Dolan, Robert; May, Suzette; May, Paul

    1983-09-01

    Rates of shoreline change and overwash penetration distances were calculated for barrier islands along the Louisiana, Mississippi, and Alabama coasts with the orthogonal grid mapping system (OGMS). Average rates of shoreline change are exceptionally high in Louisiana, being of the order -4.7 to -7.4 m yr-1. Mississippi and Alabama recession rates are lower and range from -2.0 to -3.1 m yr-1 over the period of record. Erosion rates along the shorelines of these islands have remained relatively constant over the period of study with five exceptions in coastal Louisiana and the Chandeleur-Breton Islands Arc, and two exceptions along the Mississippi-Alabama barrier islands where they have accelerated. Mean overwash penetration is greatest along Dauphin Island, Alabama, and Cat Island, Mississippi: 207.6 and 197.9 m, respectively. The Chandeleur-Brenton Islands Arc range from 88.1 m at the central barrier to 180.4 along the flanks. The Mississippi islands range from 105.2 m on Ship Island to 200.5 m along central Horn Island. Mean overwash penetration along the Louisiana barriers is highly variable: 46.3 to 211.4 m.

  9. Grazing pressure of copepods on the phytoplankton stock of the central North Sea

    NASA Astrophysics Data System (ADS)

    Baars, M. A.; Fransz, H. G.

    Measurements on gut fluorescence indicated that large stages of calanoid copepods ingested ˜6 times more chlorophyll containing particles by night than by day in the Oyster Ground area of the North Sea. No diurnal rhythm in chlorophyll pigment concentrations in the water was found in July and September. In May the chlorophyll a concentration was twice as high in the afternoon as after midnight, and ambient phaeopigment concentration showed an inverse rhythm but of small amplitude. During all 3 cruises total daily ingestion of chlorophyll by copepods was only a small fraction of ambient chlorophyll concentrations, and it is suggested that the observed rhythm in chlorophyll in May was caused not by grazing but by an internal physiological rhythm in the Cryptophyceae associated with Mesodinium. Chlorophyll ingestion and filtering rates measured in grazing experiments with labelled food were used to estimate the daily ration of phytoplankton carbon consumed by larger copepod stages. It was always low in Pseudocalanus and Calanus (4 to 8% of body carbon), higher in Temora and Centropages in May and September (˜25%). Respiration experiments showed that metabolic needs were 13%, 25% and 30% of body carbon per day in May (7°C), July (15.5°C) and September (17°C). In July and September labile POC concentrations were low (44 and 77 mg·m -3) and non-phytoplankton carbon formed the lesser part of it (14 and 39%, respectively). It is concluded that during summer most of the species studied were feeding below threshold concentrations, and, if not consuming detritus and microzooplankton, suffered from starvation. Biomass of calanoid copepods decreased from July to September, while other herbivorous species, probably more adapted to the phytoplankton composition, exceeded copepod biomass during these months. Extrapolation of the results on grazing by larger stages to the nauplii and small copepodites indicated that daily ingestion of phytoplankton carbon by the whole

  10. New insights into the origin of late Neogene sediments in the Umatilla Basin, north-central Oregon and south-central Washington

    SciTech Connect

    Lindsey, K.A. ); Tolan, T.L. . Dept. of Geology); Reidel, S.P. )

    1993-04-01

    The study of late Miocene-aged terrigenous clastic sediments in the Umatilla Basin of north-central Oregon and adjacent Klickitat Valley of southern Washington reveal important, previously unrecognized stratigraphic and lithologic trends. These sediments, comprising the upper Ellensburg and the Alkali Canyon Formations (14 to 8.5 Ma) previously have been characterized as basaltic gravels deposited in localized alluvial fans and minor air fall tuffs produced by Cascade volcanism. A minor extrabasinal (exotic) component to these sediments has been noted in some previous studies. The authors' data challenges these interpretations. Pebble counts reveal a variety of exotic clast types, including metavolcanics, laminated metasediments, quartzites, and intermediate to silicic volcanics. This assemblage of lithologies is different than those that characterize the ancestral Columbia and Salmon-Clearwater Rivers. Sedimentologic trends suggest fluvial rather than alluvial fan deposition dominated. They interpret that a major fluvial system flowed from SE to NW across the western third of the Umatilla Basin. This river exited the Umatilla Basin via the Rock Creek water gap in the Columbia Hills, flowed across the Klickitat Valley and the Horse Heaven Hills, and then intersected the ancestral Columbia River. The abundance and stratigraphic distribution of exotic clast types suggests that this river drained terranes south and east of the Blue Mountains and persisted for a significant period of time, from approximately 14.5 to 8.5 Ma.

  11. Validation of attenuation models for ground motion applications in central and eastern North America

    DOE PAGESBeta

    Pasyanos, Michael E.

    2015-11-01

    Recently developed attenuation models are incorporated into standard one-dimensional (1-D) ground motion prediction equations (GMPEs), effectively making them two-dimensional (2-D) and eliminating the need to create different GMPEs for an increasing number of sub-regions. The model is tested against a data set of over 10,000 recordings from 81 earthquakes in North America. The use of attenuation models in GMPEs improves our ability to fit observed ground motions and should be incorporated into future national hazard maps. The improvement is most significant at higher frequencies and longer distances which have a greater number of wave cycles. This has implications for themore » rare high-magnitude earthquakes, which produce potentially damaging ground motions over wide areas, and drive the seismic hazards. Furthermore, the attenuation models can be created using weak ground motions, they could be developed for regions of low seismicity where empirical recordings of ground motions are uncommon and do not span the full range of magnitudes and distances.« less

  12. Recent warming by latitude associated with increased length of ragweed pollen season in central North America

    PubMed Central

    Ziska, Lewis; Knowlton, Kim; Rogers, Christine; Dalan, Dan; Tierney, Nicole; Elder, Mary Ann; Filley, Warren; Shropshire, Jeanne; Ford, Linda B.; Hedberg, Curtis; Fleetwood, Pamela; Hovanky, Kim T.; Kavanaugh, Tony; Fulford, George; Vrtis, Rose F.; Patz, Jonathan A.; Portnoy, Jay; Coates, Frances; Bielory, Leonard; Frenz, David

    2011-01-01

    A fundamental aspect of climate change is the potential shifts in flowering phenology and pollen initiation associated with milder winters and warmer seasonal air temperature. Earlier floral anthesis has been suggested, in turn, to have a role in human disease by increasing time of exposure to pollen that causes allergic rhinitis and related asthma. However, earlier floral initiation does not necessarily alter the temporal duration of the pollen season, and, to date, no consistent continental trend in pollen season length has been demonstrated. Here we report that duration of the ragweed (Ambrosia spp.) pollen season has been increasing in recent decades as a function of latitude in North America. Latitudinal effects on increasing season length were associated primarily with a delay in first frost of the fall season and lengthening of the frost free period. Overall, these data indicate a significant increase in the length of the ragweed pollen season by as much as 13–27 d at latitudes above ~44°N since 1995. This is consistent with recent Intergovernmental Panel on Climate Change projections regarding enhanced warming as a function of latitude. If similar warming trends accompany long-term climate change, greater exposure times to seasonal allergens may occur with subsequent effects on public health. PMID:21368130

  13. East central North America climates during marine isotope stages 3-5

    NASA Astrophysics Data System (ADS)

    Springer, Gregory S.; Rowe, Harold D.; Hardt, Ben; Cheng, Hai; Edwards, R. Lawrence

    2014-05-01

    Long-term, high-resolution stalagmite carbon and oxygen isotope records from eastern North America (ENA) provide a midlatitude history of relative changes in moisture availability and climate states during the last interglacial and glacial inception (127.7 to 41.6 ka before present). The West Virginia carbon record shows low-amplitude variability at orbital time scales, superimposed on a long-term asymmetric pattern similar to global sea level changes. Relative moisture availability peaked at ~114 ka, and following a brief dry interval at ~96 ka, moisture availability gradually decreased. The almost linear change in moisture availability over ENA may reflect gradual changes in midlatitude zonal circulation as the polar cell and Laurentide Ice Sheet expanded or decreased. In contrast, our oxygen record is precession modulated and in phase with spring insolation, perhaps due to changes in precipitation seasonality. The separate pacings by eccentricity (carbon) and precession (oxygen) expose an underlying complexity that will be a challenge to explain.

  14. Validation of attenuation models for ground motion applications in central and eastern North America

    SciTech Connect

    Pasyanos, Michael E.

    2015-11-01

    Recently developed attenuation models are incorporated into standard one-dimensional (1-D) ground motion prediction equations (GMPEs), effectively making them two-dimensional (2-D) and eliminating the need to create different GMPEs for an increasing number of sub-regions. The model is tested against a data set of over 10,000 recordings from 81 earthquakes in North America. The use of attenuation models in GMPEs improves our ability to fit observed ground motions and should be incorporated into future national hazard maps. The improvement is most significant at higher frequencies and longer distances which have a greater number of wave cycles. This has implications for the rare high-magnitude earthquakes, which produce potentially damaging ground motions over wide areas, and drive the seismic hazards. Furthermore, the attenuation models can be created using weak ground motions, they could be developed for regions of low seismicity where empirical recordings of ground motions are uncommon and do not span the full range of magnitudes and distances.

  15. Current distribution of North American river otters in central and eastern Oklahoma, with seven new county records

    USGS Publications Warehouse

    Barrett, Dominic A.; Leslie,, David M., Jr.

    2010-01-01

    In 1984 and 1985, the Oklahoma Department of Wildlife Conservation reintroduced North American river otters (Lontra canadensis) from coastal Louisiana into eastern Oklahoma. Those reintroductions and immigration from Arkansas and possibly northeastern Texas allowed river otters to become reestablished in eastern Oklahoma. Our goals were to determine the contemporary distribution of river otters in central and eastern Oklahoma with voucher specimens, sign surveys, and mail surveys and to compare proportion of positive detections among watersheds. We report new distributional records with voucher specimens from seven counties (Adair, Bryan, Coal, Johnston, McIntosh, Okfuskee, Tulsa) in Oklahoma. We also provide locality information for specimens collected from four counties (Haskell, McCurtain, Muskogee, Wagoner) where river otters were described in published literature but no voucher specimens existed. During winter and spring 2006 and 2007, we visited 340 bridge sites in 28 watersheds in eastern and central Oklahoma and identified river otter signs in 16 counties where river otters were not previously documented in published literature or by voucher specimens. Proportion of positive sites within each watershed ranged 0–100%. Mail surveys suggested that river otters occurred in eight additional counties where they were not previously documented by published literature, voucher specimens, or sign-survey efforts.

  16. Environmental change in the mid-Boteti area of north-central Botswana: Biophysical processes and human perceptions

    NASA Astrophysics Data System (ADS)

    Ringrose, Susan; Chanda, Raban; Nkambwe, Musisi; Sefe, Francis

    1996-05-01

    Increased interest in environmental change issues has led researchers to consider more integrated approaches to change dynamics. This paper examines change in terms of land degradation in north-central Botswana from both biophysical and human perspectives. Although seasonal and periodic droughts were prevalent, analysis of rainfall data over the past 70 years revealed no downward trend. However, indicators of declining productivity such as soil erosion, loss of vegetation cover, and a declining groundwater table were amply evident. The GIS analysis of remotely sensed data has shown that complete vegetation recovery after drought is not taking place, particularly in the south-central part of the study area. These areas contained the highest human and livestock population densities. The local people acknowledged facing increasing resource depletion and indicated drought as the main cause. Pressures on available resources, particularly during drought periods, appeared to have impeded the regenerative capacity of the natural vegetation cover, thereby inducing land degradation. This situation may not easily be rectified because of widespread poverty and inappropriate local perceptions of the solutions. Both of these hinder the adoption of sustainable land management.

  17. Geometry and State of Stress of the Slab Beneath the North Central Andes

    NASA Astrophysics Data System (ADS)

    Kumar, A.; Beck, S. L.; Wagner, L. S.; Zandt, G.; Long, M. D.

    2012-12-01

    The central Andean plateau of southern Peru and Bolivia is one of the largest topographic features on Earth. It has strongly influenced the local and regional climate since the early Miocene by affecting the regional dynamics that control circulation and precipitation. The surface and subsurface processes responsible for the plateau formation and evolution are still unclear. There are two end member models proposed for this uplift: (1) Slow and steady rise since the late Eocene (~40 Ma) with maximum upper crustal shortening between 30 and 10 Ma or (2) rapid surface uplift of ~2.5 km in the late Miocene between 10.3 and 6.7 Ma. The rapid uplift theory argues for the wholesale removal of a thick portion of the lower eclogitic crust and upper mantle lithosphere. A slow and steady uplift of the Andes would suggest a continuous removal of the lower lithosphere or piecemeal delamination, proportional to the rate of shortening. We present earthquake locations and focal mechanisms using data from two ongoing temporary arrays: the network of 50 broadband seismic stations that was part of the NSF-Continental Dynamics-funded project "CAUGHT" (Central Andean Uplift and the Geodynamics of High Topography) and the 40 station NSF- Geophysics funded "PULSE" array (PerU Lithosphere and Slab Experiment). Our new earthquake locations provide an improved insight about the geometry of subducting Nazca slab and also put an upper bound on the thickness of overriding lithosphere. Obvious clustering of intermediate depth earthquakes suggests strong and localized release of tectonic stress in the slab at ~15.5oS. The seismic section drawn from the precisely located slab events provide a better idea about the lateral variations of the slab geometry and the geometry of asthenoshperic corner flow to help understand its geodynamic effect on the lithospheric delamination or ablative subduction process. . Focal mechanisms of the slab events are helpful in understanding the stress state of the

  18. Health outcomes among HIV-positive Latinos initiating antiretroviral therapy in North America versus Central and South America

    PubMed Central

    Cesar, Carina; Koethe, John R; Giganti, Mark J; Rebeiro, Peter; Althoff, Keri N; Napravnik, Sonia; Mayor, Angel; Grinsztejn, Beatriz; Wolff, Marcelo; Padgett, Denis; Sierra-Madero, Juan; Gotuzzo, Eduardo; Sterling, Timothy R; Willig, James; Levison, Julie; Kitahata, Mari; Rodriguez-Barradas, Maria C; Moore, Richard D; McGowan, Catherine; Shepherd, Bryan E; Cahn, Pedro

    2016-01-01

    Introduction Latinos living with HIV in the Americas share a common ethnic and cultural heritage. In North America, Latinos have a relatively high rate of new HIV infections but lower rates of engagement at all stages of the care continuum, whereas in Latin America antiretroviral therapy (ART) services continue to expand to meet treatment needs. In this analysis, we compare HIV treatment outcomes between Latinos receiving ART in North America versus Latin America. Methods HIV-positive adults initiating ART at Caribbean, Central and South America Network for HIV (CCASAnet) sites were compared to Latino patients (based on country of origin or ethnic identity) starting treatment at North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) sites in the United States and Canada between 2000 and 2011. Cox proportional hazards models compared mortality, treatment interruption, antiretroviral regimen change, virologic failure and loss to follow-up between cohorts. Results The study included 8400 CCASAnet and 2786 NA-ACCORD patients initiating ART. CCASAnet patients were younger (median 35 vs. 37 years), more likely to be female (27% vs. 20%) and had lower nadir CD4 count (median 148 vs. 195 cells/µL, p<0.001 for all). In multivariable analyses, CCASAnet patients had a higher risk of mortality after ART initiation (adjusted hazard ratio (AHR) 1.61; 95% confidence interval (CI): 1.32 to 1.96), particularly during the first year, but a lower hazard of treatment interruption (AHR: 0.46; 95% CI: 0.42 to 0.50), change to second-line ART (AHR: 0.56; 95% CI: 0.51 to 0.62) and virologic failure (AHR: 0.52; 95% CI: 0.48 to 0.57). Conclusions HIV-positive Latinos initiating ART in Latin America have greater continuity of treatment but are at higher risk of death than Latinos in North America. Factors underlying these differences, such as HIV testing, linkage and access to care, warrant further investigation. PMID:26996992

  19. Projecting the vegetation response to climatic change in the North American Central Grasslands Region

    SciTech Connect

    Lenihan, J.M.; Neilson, R.P. )

    1993-06-01

    An interdisciplinary modeling effort is underway in which high-resolution climate change projections will drive the Mapped Atmosphere-Plant-Soil System (MAPSS) to simulate vegetation change in the Central Grasslands Region. MAPSS calculates a complete site water balance and solves for the leaf area (LAI) of both woody and grass lifeforms in full competition for both light and water. Fire is a necessary constraint on simulated shrub LAI throughout much of the grasslands region, and incorporation of weather variability is critical for obtaining accurate tree/grass LAI ratios in the Prairie Peninsula. Initial estimates of the potential impact of climatic change include significant changes in both lifeform LAI and the distribution of subformation vegetation types, but the magnitude and even the direction of change varies with the climate scenario and with assumptions concerning wind speed and plant water-use efficiency.

  20. Intestinal and blood parasites in the North Lore District, Central Sulawesi, Indonesia.

    PubMed

    Carney, W P; Masri, S; Stafford, E E; Putrali, J

    1977-06-01

    Over 1,000 stool specimens from residents of the Napu and Besoa Valleys, Central Sulawesi, Indonesia were examined. Schistosoma japonicum was detected in 31% of Napu Valley residents while in only 2% of the Besoa Valley residents. Hookworm infections were the most frequently encountered helminth parasitisms in both valleys. Other helminth parasites encountered were: Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Strongyloides stercoralis, Physaloptera sp., Diphyllobothrium sp., echinostome and heterophyid trematodes. Intestinal protozoa endemic to the area were: Entamoeba histolytica, E. coli, E. hartmanni, Iodamoebe bütschlii, Giardia lamblia, Chilomastix mesnili and Trichomonas hominis. Plasmodium falciparum was responsible for malaria parasitaemias in 5% of 1353 specimens examined and Brugia malayi microfilaraemias were detected in 10% of 972 specimens examined. PMID:335530

  1. Intraspecific phylogeography of red squirrels (Tamiasciurus hudsonicus) in the central Rocky Mountain region of North America.

    PubMed

    Wilson, Gregory M; Den Bussche, Ronald A; McBee, Karen; Johnson, Lacrecia A; Jones, Cheri A

    2005-11-01

    We used variation in a portion of the mitochondrial DNA control region to examine phylogeography of Tamiasciurus hudsonicus, a boreal-adapted small mammal in the central Rocky Mountain region. AMOVA revealed that 65.66% of genetic diversity was attributable to variation within populations, 16.93% to variation among populations on different mountain ranges, and 17.41% to variation among populations within mountain ranges. Nested clade analysis revealed two major clades that likely diverged in allopatry during the Pleistocene: a southern clade from southern Colorado and a northern clade comprising northern Colorado, Wyoming, eastern Utah, and eastern Idaho. Historically restricted gene flow as a result of geographic barriers was indicated between populations on opposite sides of the Green River and Wyoming Basin and among populations in eastern Wyoming. In some instances genetic structure indicated isolation by distance. PMID:16247688

  2. Growth dynamics and biodiversity of larch forest after wildfire at the north of central Siberia

    SciTech Connect

    Danilin, I.

    1996-12-31

    Investigations of qualitative and quantitative changes occurring in disturbed forest communities in Siberia are now recognized as important issues, since anthropogenic stress is increasingly affecting forests from year to year and often results in irreversible decomposition of forest ecosystems over large areas. In forests of central Siberia, fire accounts for the greatest disturbance. The level of fire-caused forest destruction is noticeably high. Space imagery analysis has revealed that, from 1980 throughout 1995, the average annual forest area covered by fires was more than 500,000 ha. In as much as this is a country with permafrost soils, fires promote swamping and treeless areas. However, forests regenerate naturally on some burned areas. Forest regeneration can occur either with stand replacement (through secondary birch) or without replacement when new forests are formed by the pre-fire edificators. The second way of succession is ecologically more preferable, because the larch population is more resistant to external influences and keeps its native biodiversity.

  3. Genetic Variability and Phylogeny of High Risk HPV Type 16, 18, 31, 33 and 45 L1 Gene in Greek Women

    PubMed Central

    Ntova, Chara Kleio; Kottaridi, Christine; Chranioti, Aikaterini; Spathis, Aris; Kassanos, Dimitrios; Paraskevaidis, Evangelos; Karakitsos, Petros

    2012-01-01

    The present study explores nucleotide variability, phylogeny and association with cervical neoplasia in high risk HPV types 16, 18, 31, 33 and 45 collected from Greek women. Of the 1894 women undergoing routine cervical cytology examination, 160 samples test positive for single infections of HPV type 16 (n = 104), HPV 31 (n = 40), HPV 33 (n = 7), HPV 18 (n = 5), and HPV 45 (n = 4) were typed by microarrays method, amplified by PCR then sequenced and phylogenetically analyzed. For HPV 16, 9 variants with nucleotide variations were included into the study. For HPV 31, 33, 18 and 45, nucleotide variations were identified in 6, 4, 2 and 3 variants, respectively. The Bayesian inference and Maximum Parsimony methods were used in order to construct the phylogenetic trees. When types were analyzed independently HPV 16 (European and non-European) and HPV 18 (African and non-African) formed distinct clades. The genomic characterization of HPV variants will be important for illuminating the geographical relatedness and biological differences and for the determination of their risk. PMID:22312235

  4. Monosomy 1p36.31-33{yields}pter due to a paternal reciprocal translocation: Prognostic significance of FISH analysis

    SciTech Connect

    Blennow, E.; Bui, The-Hung; Wallin, A.

    1996-10-02

    A rare monosomy 1p36.31-33{r_arrow}pter was found in a child with physical anomalies, psycho-motor retardation, and seizures. Cytogenetic investigation suggested an unbalanced translocation between 1p and an acrocentric chromosome, but the rearrangement was difficult to assess accurately using conventional chromosome banding techniques. The half-cryptic translocation was further characterized using fluorescence in situ hybridization, and the aberrant chromosome 1 was shown to be a derivate of a paternal reciprocal translocation t(1;15)(p36.31-33;p11.2-12). The breakpoints on chromosome 1 and 15 were defined in detail using locus specific probes. The rearrangement did not include the region on chromosome 1p which previously has been suggested to predispose to the development of neuroblastoma in a case with a constitutional translocation. At 3 6/12 years, the patient has no clinical signs of this disease, which illustrates the prognostic significance of this investigation. 30 refs., 4 figs., 1 tab.

  5. Atlantic Multidecadal Oscillation (AMO) modulates dynamics of small pelagic fishes and ecosystem regime shifts in the eastern North and Central Atlantic

    NASA Astrophysics Data System (ADS)

    Alheit, Jürgen; Licandro, Priscilla; Coombs, Steve; Garcia, Alberto; Giráldez, Ana; Santamaría, Maria Teresa Garcia; Slotte, Aril; Tsikliras, Athanassios C.

    2014-03-01

    Dynamics of abundance and migrations of populations of small pelagic clupeoid fish such as anchovy (Engraulis encrasicolus), sardine (Sardina pilchardus), sardinella (Sardinella aurita), sprat (Sprattus sprattus) and herring (Clupea harengus) in the eastern North and Central Atlantic between Senegal and Norway vary in synchrony with the warm and cool phases of the Atlantic Multidecadal Oscillation (AMO). This is shown by compiling retrospective data on fish catches and anecdotal observations, which in some cases date back to the mid-19th century. The AMO is defined as the de-trended mean of North Atlantic (0-60°N) sea surface temperature anomalies. However, it is not primarily the temperature which drives the dynamics of the small pelagic fish populations. Instead, the AMO seems to be a proxy for complex processes in the coupled atmosphere-ocean system of the North Atlantic. This is manifested in large-scale changes in strength and direction of the current system that move water masses around the North Atlantic and likely involves the North Atlantic Oscillation (NAO), the Atlantic Meridional Overturning Circulation (AMOC), the Mediterranean Overflow Water (MOW) and the subpolar gyre (SPG). The contractions and expansions of the SPG apparently play a key role. This was particularly obvious in the mid-1990s, when the SPG abruptly contracted with the result that warm subtropical water masses moved to the north and east. Small pelagic fish populations in the eastern North and Central Atlantic, including those in the Mediterranean responded quickly by changing abundances and migrating northwards. It seems that the complex ocean-atmosphere changes in the mid-1990s, which are described in the text in detail, caused a regime shift in the ecosystems of the eastern North and Central Atlantic and the small pelagic clupeoid fish populations are the sentinels of this shift.

  6. Reprint of “Atlantic Multidecadal Oscillation (AMO) modulates dynamics of small pelagic fishes and ecosystem regime shifts in the eastern North and Central Atlantic”

    NASA Astrophysics Data System (ADS)

    Alheit, Jürgen; Licandro, Priscilla; Coombs, Steve; Garcia, Alberto; Giráldez, Ana; Santamaría, Maria Teresa Garcia; Slotte, Aril; Tsikliras, Athanassios C.

    2014-05-01

    Dynamics of abundance and migrations of populations of small pelagic clupeoid fish such as anchovy (Engraulis encrasicolus), sardine (Sardina pilchardus), sardinella (Sardinella aurita), sprat (Sprattus sprattus) and herring (Clupea harengus) in the eastern North and Central Atlantic between Senegal and Norway vary in synchrony with the warm and cool phases of the Atlantic Multidecadal Oscillation (AMO). This is shown by compiling retrospective data on fish catches and anecdotal observations, which in some cases date back to the mid-19th century. The AMO is defined as the de-trended mean of North Atlantic (0-60°N) sea surface temperature anomalies. However, it is not primarily the temperature which drives the dynamics of the small pelagic fish populations. Instead, the AMO seems to be a proxy for complex processes in the coupled atmosphere-ocean system of the North Atlantic. This is manifested in large-scale changes in strength and direction of the current system that move water masses around the North Atlantic and likely involves the North Atlantic Oscillation (NAO), the Atlantic Meridional Overturning Circulation (AMOC), the Mediterranean Overflow Water (MOW) and the subpolar gyre (SPG). The contractions and expansions of the SPG apparently play a key role. This was particularly obvious in the mid-1990s, when the SPG abruptly contracted with the result that warm subtropical water masses moved to the north and east. Small pelagic fish populations in the eastern North and Central Atlantic, including those in the Mediterranean responded quickly by changing abundances and migrating northwards. It seems that the complex ocean-atmosphere changes in the mid-1990s, which are described in the text in detail, caused a regime shift in the ecosystems of the eastern North and Central Atlantic and the small pelagic clupeoid fish populations are the sentinels of this shift.

  7. High-resolution single-channel seismic reflection surveys of Orange Lake and other selected sites of north central Florida

    USGS Publications Warehouse

    Kindinger, Jack G.; Davis, Jeffrey B.; Flocks, James G.

    1994-01-01

    The potential fluid exchange between lakes of north central Florida and the Floridan aquifer and the process by which exchange occurs is of critical concern to the St. Johns Water Management District. High-resolution seismic tools with relatively new digital technology were utilized in collecting geophysical data from Orange, Kingsley, Lowry and Magnolia Lakes, and the Drayton Island area of St. Johns River. The data collected shows the application of these techniques in understanding the formation of individual lakes, thus aiding in the management of these natural resources by identifying breaches or areas where the confining units are thin or absent between the water bodies and the Floridan aquifer. Orange Lake, the primary focus of the study, is a shallow flooded plain that was formed essentially as an erosional depression in the clayey Hawthorn formation. The primary karstic features identified in the lake were cover subsidence, cover collapse and buried sinkholes structures in various sizes and stages of development. Orange Lake was divided into three areas southeast, southwest, and north-central. Karst features within the southeast area of Orange Lake are mostly cover subsidence sinkholes and associated features. Many of the subsidence features found are grouped together to form larger composite sinkholes, some greater than 400 m in diameter. The size of these composite sinkholes and the number of buried subsidence sinkholes distinguish the southeast area from the others. The potential of lake waters leaking to the aquifer in the southeast area is probably controlled by the permeability of the cover sediments or by fractures that penetrate the lake floor. The lake bottom and subsurface of the north-central areas are relatively subsidence sinkholes that have no cover sediments overlying them, implying that the sinks have been actively subsiding with some seepage into the aquifer from the lake in this area due to the possible presence of the active subsidence

  8. Habitat of oil in the Lindsborg field, Salina basin, north-central Kansas

    SciTech Connect

    Newell, K.D. )

    1991-03-01

    The Lindsborg field was discovered in 1938, and is now 14 mi in length and 1-2 mi in width. It has a projected ultimate recovery of 16 MMBO. Three pay zones (5-20 ft thick) produce in the field. The Simpson pay zone (Middle Ordovician) is a well-rounded, quartzitic sandstone that is interpreted to be a paralic, high-energy shelf deposit. The Viola pay (Middle Ordovician) appears to be a dolomitic, lime grainstone but no cores are available to confirm this. The uppermost pay zone, the Upper Ordovician Maquoketa, is a finely laminated, vuggy, cherry dolomite interpreted to have been deposited as a subtidal lime mudstone in a restricted lagoon. The Simpson and Viola pays are structurally trapped in culminations along the crest of the Lindsborg anticline. Although the Maquoketa pay is structurally trapped with the other pay zones in the southern half of the field, its locus of production in the north half of the fields extends 100 ft vertically down the western flank of the anticline. The trapping mechanism is unclear due to lack of core control and modern logging suites, but it may be subtle updip diagenetic change from vuggy to nonvuggy dolomite. The Simpson and Maquoketa oils are geochemically distinct. Both may reflect efficient local source-to-reservoir migration from originally rich but marginally mature Ordovician and Devonian shales that contact each pay zone. If oil in the Lindsborg field is locally generated, the prospectivity of the relatively unproductive and underexplored Salina basin may be enhanced.

  9. Deformation of the Roberts Mountains Allochthon in north-central Nevada

    USGS Publications Warehouse

    Evans, James George; Theodore, Ted G.

    1978-01-01

    During the Antler orogeny in Late Devonian and Early Mississippian time, early and middle Paleozoic siliceous rocks, largely chert and sha1e, were thrust eastward for 90 to 160 km over coexisting carbonate rocks. Minor and major structures of two small areas of the allochthon at Battle Mountain and in the southern Tuscarora Mountains were studied in order to characterize the deformation and test the consistency of the movement plan with respect to the large eastward displacement. In the Battle Mountain area, the lower Paleozoic Scott Canyon and Valmy Formations were deformed in the Antler orogeny but were unaffected by later tectonism during late Paleozoic or early Mesozoic. In the southern Tuscarora Mountains area, the Ordovician and Silurian siliceous rocks deformed in the Antler Orogeny were deformed by later, possibly Mesozoic, folding and thrusting. Most of the minor folding visible in the allochthon is in the cheret, but proportionally more of the strain was taken up in the shale and argillite, both poorly exposed but predominant rock types. Most minor folds, concentric in form, plunge at small angles to the north-northeast and south-southwest with steeply dipping or vertical axial planes. The b-fabric axis, parallel to these folds, is identical apparently to the B-kinematic axis. The horizontal component of tectonic shortening of the allochthon, N. 70?-75? W. both in the Battle Mountain area and in the southern Tuscarora Mountains area, is therefore consistent with an eastward direction of movement of the allochthon. Folds with west- northwest trends locally present in the allochthon, may have formed in the direction of tectonic transport. In the southern Tuscarora Mountains, local strain in and below the allochthon was different from the prevailing strain in the allochthon, and tectonic shortening was locally at large angles to the accepted direction of movement of the allochthon.

  10. Radionuclides reveal age and source of aerosols collected over central North Atlantic

    NASA Astrophysics Data System (ADS)

    Zhang, B.; Urban, N. R.; Perlinger, J. A.; Owen, R. C.; China, S.; Mazzoleni, C.; Mazzoleni, L. R.

    2014-12-01

    Aerosol filter samples were collected daily during summer 2013, at the Pico Mountain Observatory (PMO, 38.47°N, 28.40°W, 2,225 m a.s.l.), Azores Islands. PMO monitors free troposphere air and aerosols transported from neighboring continents; North America has the most frequent influence due to predominantly westerly winds in mid-latitude regions, while aerosols from Europe and Africa are sampled occasionally. The residence time during long-range transport in the atmosphere has a critical impact on aerosol chemical and physical properties, and it can be estimated by measuring activities of radionuclides attached to aerosols. 210Pb (t1/2 = 22.1 years) and 210Po (t1/2 = 138 days) are daughter nuclides in the decay chain of 222Rn, an inert gas species produced throughout the Earth's crust and emitted into the atmosphere. Due to different rates of decay, the activity ratio of 210Po to 210Pb can be used to estimate atmospheric residence times of the carrier aerosols. 210Po activity counting of 58 samples was conducted to investigate aerosol residence times in this study. 210Po activity was measured twice serially for each aerosol sample to predict the initial activity of 210Po on the sampling date and the activity of very slowly decaying 210Pb. Aerosol ages calculated by the activity ratio of 210Po to 210Pb were compared with air tracer ages simulated using the FLEXible PARTicle dispersion model (FLEXPART) and studied together with aerosol particle physical properties. The activity of terrestrial radionuclides per unit of aerosol mass can also reveal source information of the aerosols. FLEXPART backward trajectories will be used to verify correlations between source regions and activity of radionuclides in aerosols. In previous research related to long-range atmospheric transport to PMO, FLEXPART has proven to be reliable in identifying upwind source regions.

  11. Polyphase Alpine deformation at the northern edge of the Menderes Taurus block, North Konya, Central Turkey

    NASA Astrophysics Data System (ADS)

    Eren, Yasar

    2001-10-01

    Low-grade metamorphic rocks of Paleozoic-Mesozoic age to the north of Konya, consist of two different groups. The Silurian-Lower Permian Sizma Group is composed of reefal complex metacarbonates at the base, and flyschoid metaclastics at the top. Metaigneous rocks of various compositions occur as dykes, sills, and lava flows within this group. The ?Upper Permian-Mesozoic age Ardicli Group unconformably overlies the Sizma Group and is composed of, from bottom to top, coarse metaclastics, a metaclastic-metacarbonate alternation, a thick sequence of metacarbonate, and alternating units of metachert, metacarbonates and metaclastics. Although pre-Alpine overthrusts can be recognized in the Sizma Group, intense Alpine deformation has overprinted and obliterated earlier structures. Both the Sizma and Ardicli Groups were deformed, and metamorphosed during the Alpine orogeny. Within the study area evidence for four phases of deformation and folding is found. The first phase of deformation resulted in the major Ertugrul Syncline, overturned tight to isoclinal and minor folding, and penetrative axial planar cleavage developed during the Alpine crustal shortening at the peak of metamorphism. Depending on rock type, syntectonic crystallization, rotation, and flattening of grains and pressure solution were the main deformation mechanisms. During the F 2-phase, continued crustal shortening produced coaxial Type-3 refolded folds, which can generally be observed in outcrop with associated crenulation cleavage (S 2). Refolding of earlier folds by the noncoaxial F 3-folding event generated Type-2 interference patterns and the major Meydan Synform which is the largest map-scale structure within the study area. Phase 3 structures also include crenulation cleavage (S 3) and conjugate kink folds. Further shortening during phase 4 deformation also resulted in crenulation cleavage and conjugate kink folds. According to thin section observations, phases 2-4 crenulation cleavages are mainly

  12. Geometry, evolution, and tectonic framework of the Skeena Fold Belt, north central British Columbia

    NASA Astrophysics Data System (ADS)

    Evenchick, Carol A.

    1991-06-01

    The Intermontane Belt of the Canadian Cordillera has long been viewed as a passive, relatively rigid block between two metamorphic-plutonic belts, the Coast Plutonic Complex and the Omineca Belt. However, the Skeena Fold Belt, which spans most of the width of the northern Intermontane Belt, exhibits shortening comparable with that in the Rocky Mountain Fold and Thrust Belt. The Skeena Fold Belt has many features of thin-skinned fold and thrust belts, such as thrust faults which sole into a detachment, a wide variety of structural styles which depend on rock type, a foreland basin which was cannibalized by continued deformation, a frontal triangle zone, and a hinterland of metamorphic and plutonic rocks (Coast Plutonic Complex). The Skeena Fold Belt thus is comparable with the Rocky Mountain Fold and Thrust Belt, but rather than deforming a continental terrace wedge, it developed in a terrane (Stikinia) which had accreted to North America in the early Mesozoic, and in Jurassic and Cretaceous clastic successions (Bowser Lake and Sustut groups) which overlie Stikinia. Structural and stratigraphic relationships show that the earliest deformation occurred between Oxfordian and Albian time and that the last folds developed in latest Cretaceous or early Tertiary time. As much as 160 km of northeastward shortening in the Skeena Fold Belt was broadly contemporaneous with crustal thickening in the Coast Plutonic Complex and Omineca Belt, with dextral strike-slip faulting east of the Skeena Fold Belt, and with shortening in the Rocky Mountain Fold and Thrust Belt. Therefore, between latest Jurassic and early Tertiary times, horizontal shortening occured across most of the width of the northern Canadian Cordillera. Concurrent shortening across the Cordillera suggests that a common detachment (or detachments) fed all of these zones as far east as the Rocky Mountain Fold and Thrust Belt.

  13. Mid-Cretaceous unconformity in the Methow basin, north-central Washington

    SciTech Connect

    Haugerud, R.A.; Hurlow, H.A. ); Tabor, R.W. ); Snee, L.W. )

    1993-04-01

    New mapping in the Methow basin demonstrates a significant unconformity beneath mid-Cretaceous strata of the Pasayten Group and may explain stratigraphic contrasts puzzling to earlier workers. The Pasayten Group, defined along regional strike to the north in Manning Park, includes Virginia Ridge Fm. (shallow-marine argillite and chert-clast-rich sandstone and conglomerate), Winthrop Sandstone (fluvial arkose), and Midnight Peak Fm. (redbeds and andesitic volcanic rocks) in ascending stratigraphic order. Local unconformities and lateral gradations amongst Pasayten Group units result in no one unit lying above the unconformity. Hornblende from Midnight Peak andesite on Isabella Ridge yields an [sup 40]Ar-[sup 39]Ar age of 87.0 [+-] 0.4 (1[sigma]) Ma, though Pasayten Group strata elsewhere are intruded by 88--90 Ma plutons and thus much of the unit is older. From west to east the Pasayten Group lies on progressively older strata. In upper Three Fools Creek, west of the Cascade crest, it lies on unnamed marine strata, more than 1 km thick, which conformably overlie 3 km of sand-rich turbidites of the Albian Harts Pass Fm. In the Osceola Peak-Harts Pass area it lies on upper Harts Pass turbidites. Southwest of Monument 85 and west of Hidden Lakes it lies on probable Early Cretaceous (pre-Harts Pass-age) lithic marine sandstone and siltstone. On Isabella Ridge it lies on [approximately]150 Ma tonalite and older volcanic rocks. This unconformity predates most of the conspicuous thrusts and related folds that characterize the Methow basin. Adjacent to the Pasayten fault, pre- and intra-Pasayten Group unconformities have reduced the stratigraphic section to scraps of Winthrop Sandstone and probable lower Cretaceous conglomerate locally preserved between Midnight Peak andesite and older volcanic rocks, suggesting continued early and mid-Cretaceous movement along the Pasayten fault.

  14. New data on the unresolved paradox of the Tibesti crater paleolakes (Central Sahara, North Chad)

    NASA Astrophysics Data System (ADS)

    Kroepelin, S.; Darius, F.; Deschamps, P.; Dinies, M.; Hoelzmann, P.; Kuper, J.; Oppenheimer, C.; Soulié-Märsche, I.; Sylvestre, F.

    2015-12-01

    Recent field work in the volcanic Tibesti Mountains opens a new chapter in the reconstruction of the last climatic cycles in the central Sahara and their lacustrine environments. For the first time, complete lacustrine sections were sampled in the 900 m deep crater of Trou au Natron at Pic Toussidé (3,315 m a.s.l.), and in 800 m deep Era Kohor, the major sub-caldera of Emi Koussi, the Sahara's 3,445 m high peak (photo). The probed diatomites are located 360 and 125 m above the present-day bottom of the calderas. Studies in the 1960s suggested that lake levels in the Trou au Natron were 300-500 m high at 12,400-14,970 uncal. yrs BP. Such lake depths and resulting water volumes, however, are hardly conceivable in view of the limited intake area and precipitation-evaporation ratios which would have required local rainfall by far surpassing estimates for latitudes 19-21°N from the full-Holocene record of Lake Yoa situated 460 or 220 km southeast, and 1,550 or 2,450 m lower. The presentation will examine whether differences in altitude may explain unparalleled lake depths and postglacial humid conditions 4,000-7,000 years earlier than in the surrounding lowlands, and present alternative hypotheses of lake formation in this Saharan key region.

  15. Post-collisional magmatism in the central East African Orogen: The Maevarano Suite of north Madagascar

    USGS Publications Warehouse

    Goodenough, K.M.; Thomas, Ronald J.; De Waele, B.; Key, R.M.; Schofield, D.I.; Bauer, W.; Tucker, R.D.; Rafahatelo, J.-M.; Rabarimanana, M.; Ralison, A.V.; Randriamananjara, T.

    2010-01-01

    Late tectonic, post-collisional granite suites are a feature of many parts of the Late Neoproterozoic to Cambrian East African Orogen (EAO), where they are generally attributed to late extensional collapse of the orogen, accompanied by high heat flow and asthenospheric uprise. The Maevarano Suite comprises voluminous plutons which were emplaced in some of the tectonostratigraphic terranes of northern Madagascar, in the central part of the EAO, following collision and assembly during a major orogeny at ca. 550 Ma. The suite comprises three main magmatic phases: a minor early phase of foliated gabbros, quartz diorites, and granodiorites; a main phase of large batholiths of porphyritic granitoids and charnockites; and a late phase of small-scale plutons and sheets of monzonite, syenite, leucogranite and microgranite. The main phase intrusions tend to be massive, but with variably foliated margins. New U-Pb SHRIMP zircon data show that the whole suite was emplaced between ca. 537 and 522 Ma. Geochemically, all the rocks of the suite are enriched in the LILE, especially K, and the LREE, but are relatively depleted in Nb, Ta and the HREE. These characteristics are typical of post-collisional granitoids in the EAO and many other orogenic belts. It is proposed that the Maevarano Suite magmas were derived by melting of sub-continental lithospheric mantle that had been enriched in the LILE during earlier subduction events. The melting occurred during lithospheric delamination, which was associated with extensional collapse of the East African Orogen. ?? 2009 Natural Environment Research Council.

  16. Shale-filled channel system in Wilcox Group (Paleocene-Eocene), north-central south Louisiana

    SciTech Connect

    McCulloh, R.P.; Eversull, L.G.

    1986-09-01

    Anomalously thick shale intervals of limited extent within normally sandy facies of the Wilcox are evident on published regional electric log structure sections through south Louisiana. These intervals were investigated with a series of subregional stratigraphic electric log sections and by mapping. The stratigraphic sections show that in places the shale cuts out nearly 1000 ft (300 m) of adjacent interstratified sandstone and shale section and has lenticular, channel-like, cross-sectional geometry. The sections also indicate that the uppermost parts of the thick shale intervals are stratigraphically equivalent to, or at least contiguous with, a persistent subregional shale marker bed known informally as the Big Shale, but are distinguishable from it in places by more uniform log character. A map of the anomalously thick and uniform shale indicates a south-trending, relatively straight channel with a single bifurcation in southern Avoyelles Parish. The branches probably continue downdip, although they cannot be traced with confidence south of central St. Landry Parish because of the overall shalier Wilcox section and scarcity of adequately deep control wells. The channel shale is analogous to other early Cenozoic subsurface truncational shale masses that have been mostly interpreted as submarine canyon-channel fills. Stratigraphic trapping possibilities are evident from the truncation of bounding permeable units, but the possible continuation of the branches downdip suggests the potential for deep sandy equivalents and deep gas.

  17. Floristic composition and vegetation analysis in Hail region north of central Saudi Arabia.

    PubMed

    El-Ghanim, Wafaa M; Hassan, Loutfy M; Galal, Tarek M; Badr, Abdelfattah

    2010-04-01

    In this study, 19 sites representing different habitats in Hail region were regularly visited for two years, in each site 2-5 stands were selected for investigating floristic composition and vegetation types in the area. A total of 124 species representing 34 families were recorded. The family Asteraceae is represented by the highest number of species (21 species) followed by the Poaceae (17 species) and the Brassicaceae (10 species) whereas, 15 families including Acanthaceae, Convolvulaceae, Moraceae, Nyctaginaceae and Primulaceae, are represented by a single species each. Chronological analysis of the vegetation in the area revealed the domination of Saharo-Sindian elements in the wild vegetations and of weedy species in the cultivated plots. Therophytes and chamaephytes are the dominating life forms of the vegetation spectra; therophytes represent 49.20% and chamaephytes represent 29.00% of the total species in the study area. Application of TWINISPAN and DECORANA classification and ordination techniques to the data produced seven vegetation groups. Ruderal habitats comprised two small groups A and F dominated by Phragmites australis and Imperata cylindrical (A), Euphorbia peplus and Sisymbrium irio (F), respectively. Two vegetation groups (B and G) have been recognized in the mountains and slopes dominated by Launaea mucronata, Trigonella stellata (B) and Ficus palmate and Fagonia bruguieri (G). Other two groups (C and E) inhabit the desert and mountainous wadies; these are represented by Gymnocarpos decandrus and Ochradenus baccatus (C) and Senecio glaucus subsp. coronopifolius and Rumex equisetiforme (E). On the other hand, one group (D) inhabits the cultivated plots and is represented by Plantago albicans and Rumex vesicarius, the last group also includes species restricted to the sand dune habitat of the Al-Nafud desert north of Hail city and represented by Calligonum polygonoides and Halyxolon salicornicum. The vegetation analysis indicated the invasion of

  18. Late Early Permian continental ichnofauna from Lake Kemp, north-central Texas, USA

    USGS Publications Warehouse

    Lucas, S.G.; Voigt, S.; Lerner, A.J.; Nelson, W.J.

    2011-01-01

    Continental trace fossils of Early Permian age are well known in the western United States from Wolfcampian (~. Asselian to Artinskian) strata, but few examples are known from Leonardian (~. Kungurian) deposits. A substantial ichnofauna from strata of the lower part of the Clear Fork Formation at Lake Kemp, Baylor County, Texas, augments the meager North American record of Leonardian continental trace fossil assemblages. Ichnofossils at Lake Kemp occur in the informally-named Craddock dolomite member of the Clear Fork Formation, which is 12-15. m above the local base of the Clear Fork. The trace-bearing stratum is an up-to-0.3. m thick, laminated to flaser-bedded, dolomitic siltstone that also contains mud cracks, raindrop impressions, microbially induced mat structures, and some land-plant impressions. We interpret the Craddock dolomite member as the feather-edge of a marine transgressive carbonate deposit of an irregular coastline marked by shallow bays or estuaries on the eastern shelf of the Midland basin, and the trace-fossil-bearing stratum at Lake Kemp is an unchannelized flow deposit on a muddy coastal plain. The fossil site at Lake Kemp yields a low to moderately diverse fauna of invertebrate and vertebrate traces. A sparse invertebrate ichnofauna consists of arthropod feeding and locomotion traces assigned to Walpia cf. W. hermitensis White, 1929 and Diplichnites gouldi Gevers in Gevers et al., 1971. Tetrapod footprints are most common and assigned to Batrachichnus salamandroides (Geinitz, 1861), cf. Amphisauropus kablikae (Geinitz and Deichm??ller, 1882), and Dromopus lacertoides (Geinitz, 1861), which represent small temnospondyl, seymouriamorph, and basal sauropsid trackmakers. Both the traces and sedimentary features of the fossil horizon indicate a freshwater setting at the time of track formation, and the trace assemblage represents the Scoyenia ichnofacies and the Batrachichnus ichnofacies in an overbank environment with sheet flooding and shallow

  19. Regional Tectonic Framework and Human Activities on the North Central Part of The Mexican Volcanic Belt.

    NASA Astrophysics Data System (ADS)

    Nieto-Obregon, J.

    2001-12-01

    Faults and fractures northeasterly oriented dipping NW and SE, with slips mainly normal with a slight left lateral component, affect a suite of rocks of Mesozoic to Pleistocene age, in the area of El Bajio, in the states of Queretaro, Guanajuato, Michoacan, and Aguascalientes. The faults and fractures have affected the infrastructure of the cities and surroundings of Queretaro, Celaya, Salamanca, Irapuato, Silao, Leon and Aguascalientes. In the city of Queretaro, the Tlacote-Balvanera active fault has developed a scarp and its motion may potentially affect life lines of great importance. In Celaya City a N-S trending fault traverses the city and has produced a step wise scarp more than 1.80 m high, damaging houses, streets and life lines. In Salamanca, a fault trending N 60oE, dipping to the SE extends from Cerro Gordo to the SW traversing the city and affecting with a varying degree its infrastructure. Displacements observed within the urban area reach as much as 50 cm. Close to Irapuato City, in a quarry near La Valencianita village, a N 45oE trending fault dipping to the NW affects a lacustrine sequence bearing calcareous horizons. The fault exhibits a throw of 10 m and passes north of the urban area. A similarly oriented fault traverses the city of Irapuato, and near the Traffic Circle of Puente de Guadalupe, changes its strike to the SE and continues to the city limits. In the city of Silao, a fault oriented N 60oE, traverses the city and continues to the SW up to the localities of Venta de Ramales and La Aldea. Important displacements in urban and rural areas reach more than 60 cm. Outside the city of Leon in the junction of the highways to Aguascalientes and Guadalajara a normal fault plane NE oriented and dipping SE shows striations compatible with a normal left lateral motion. Faulting is associated with old buried scarps controlled by pre existing faults, and over exploited aquifers. Some of these faults however are considered potentially active based on

  20. Floristic composition and vegetation analysis in Hail region north of central Saudi Arabia

    PubMed Central

    El-Ghanim, Wafaa M.; Hassan, Loutfy M.; Galal, Tarek M.; Badr, Abdelfattah

    2010-01-01

    In this study, 19 sites representing different habitats in Hail region were regularly visited for two years, in each site 2–5 stands were selected for investigating floristic composition and vegetation types in the area. A total of 124 species representing 34 families were recorded. The family Asteraceae is represented by the highest number of species (21 species) followed by the Poaceae (17 species) and the Brassicaceae (10 species) whereas, 15 families including Acanthaceae, Convolvulaceae, Moraceae, Nyctaginaceae and Primulaceae, are represented by a single species each. Chronological analysis of the vegetation in the area revealed the domination of Saharo-Sindian elements in the wild vegetations and of weedy species in the cultivated plots. Therophytes and chamaephytes are the dominating life forms of the vegetation spectra; therophytes represent 49.20% and chamaephytes represent 29.00% of the total species in the study area. Application of TWINISPAN and DECORANA classification and ordination techniques to the data produced seven vegetation groups. Ruderal habitats comprised two small groups A and F dominated by Phragmites australis and Imperata cylindrical (A), Euphorbia peplus and Sisymbrium irio (F), respectively. Two vegetation groups (B and G) have been recognized in the mountains and slopes dominated by Launaea mucronata, Trigonella stellata (B) and Ficus palmate and Fagonia bruguieri (G). Other two groups (C and E) inhabit the desert and mountainous wadies; these are represented by Gymnocarpos decandrus and Ochradenus baccatus (C) and Senecio glaucus subsp. coronopifolius and Rumex equisetiforme (E). On the other hand, one group (D) inhabits the cultivated plots and is represented by Plantago albicans and Rumex vesicarius, the last group also includes species restricted to the sand dune habitat of the Al-Nafud desert north of Hail city and represented by Calligonum polygonoides and Halyxolon salicornicum. The vegetation analysis indicated the invasion

  1. A Report to the U.S. Department of Education on Educational Challenges and Technical Assistance Needs for the North Central Region

    ERIC Educational Resources Information Center

    CNA Corporation, 2005

    2005-01-01

    The North Central Regional Advisory Committee (NC RAC) final report provides our assessment of the technical assistance needs of educators in our region. The technical assistance is to be provided by comprehensive centers and directed toward implementing the programs of the No Child Left Behind (NCLB) Act and achieving its goals through the use of…

  2. Triton College 1999 NCA Self-Study Report. Prepared for the North Central Association of Colleges and Schools Commission on Institutions of Higher Education.

    ERIC Educational Resources Information Center

    Triton Coll., River Grove, IL.

    The primary purpose of this report is to demonstrate that Triton College meets the North Central Association's (NCA's) twenty-four General Institutional Requirements and satisfies NCA's five criteria of Educational Excellence. To achieve this goal, the report presents a comprehensive picture of Triton College's mission, organization, programs, and…

  3. Mennonite Country: The Role of Latina Leaders in the Familial, Social, and Educational Outreach of Immigrant Latino Families in North Central Indiana

    ERIC Educational Resources Information Center

    López, Anayeli; Anguiano, Rubén P. Viramontez

    2013-01-01

    This study explored the role of Latina leaders in serving Latino families in North Central Indiana and how they produced social capital through service and leadership. The larger sample of the ethnographic study consisted of 40 Latino families (63 parents) and 14 school personnel. This study focused specifically on 13 Latina women who were…

  4. Increasing the Supply of Quality, Accessible, Affordable Child Care: An Economic Development Strategy for the North Central Region. NCRCRD Policy Briefs

    ERIC Educational Resources Information Center

    Traill, Saskia; Brown, Brentt

    2005-01-01

    The child care industry has not been fully integrated into economic development activities despite its growing importance in the economy. This is, in large part, because child care is not usually thought of as an element of economic development. As a result, states in the North Central region are not maximizing the economic benefits from quality,…

  5. Discovery of new Ohbayashinema spp. (nematoda: heligomosomoidea) in Ochotona princeps and O. cansus (lagomorpha: ochotonidae) from western North America and central Asia, with considerations of historical biogeography

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three new species of Ohbayashinema (Nematoda, Heligmosomoidea) are described from localities in western North America and central Asia. Two of these species, Ohbayashinema nearctica n. sp and O. aspeira n. sp. are parasitic in American pika, Ochotona princeps. Ohbayashinema nearctica is differentiat...

  6. Educating Black Librarians. Papers from the 50th Anniversary Celebration of the School of Library and Information Sciences, North Carolina Central University.

    ERIC Educational Resources Information Center

    Speller, Benjamin F., Jr., Ed.

    This document assembles 16 papers given at a 1989 symposium in honor of the 50th anniversary of the School of Library and Information Sciences at North Carolina Central University, Durham (NCCU). The papers examine the past, present, and future of the participation of African Americans in the field of library and information service. Titles…

  7. Year-Round School versus Traditional School: The Impact of Academic Calendars on Student Achievement at Selected Elementary Schools in North Central South Carolina

    ERIC Educational Resources Information Center

    Lindsay-Brown, Sandra J.

    2010-01-01

    This study examined the impact that a year-round school calendar and a traditional school calendar may have on student achievement at selected elementary schools in North Central South Carolina. Specifically it investigated mean differences in academic achievement between elementary students at two year-round schools versus two traditional…

  8. A Descriptive and Economic Analysis of Agricultural Teacher Education Programs in Land-Grant Universities of the North-Central Region.

    ERIC Educational Resources Information Center

    Trede, Larry D.; Crawford, Harold R.

    1981-01-01

    Presents a study which assessed the inputs and outputs of the agricultural programs of land-grant universities in the North-Central region. It was found that programs in this region are fairly homogeneous, particularly at the undergraduate level. (CT)

  9. Climatology of aerosol optical depth in North-Central Oklahoma: 1992-2008

    SciTech Connect

    Michalsky, J.; Schwartz, S.; Denn, F.; Flynn, C.; Hodges, G.; Kiedron, P.; Koontz, A.; Schlemmer, J., and Schwartz, S. E

    2010-04-01

    Aerosol optical depth (AOD) has been measured at the Atmospheric Radiation Measurement Program central facility near Lamont, Oklahoma, since the fall of 1992. Most of the data presented are from the multifilter rotating shadowband radiometer, a narrow-band, interference-filter Sun radiometer with five aerosol bands in the visible and near infrared; however, AOD measurements have been made simultaneously and routinely at the site by as many as three different types of instruments, including two pointing Sun radiometers. Scatterplots indicate high correlations and small biases consistent with earlier comparisons. The early part of this 16 year record had a disturbed stratosphere with residual Mt. Pinatubo aerosols, followed by the cleanest stratosphere in decades. As such, the last 13 years of the record reflect changes that have occurred predominantly in the troposphere. The field calibration technique is briefly described and compared to Langley calibrations from Mauna Loa Observatory. A modified cloud-screening technique is introduced that increases the number of daily averaged AODs retrieved annually to about 250 days compared with 175 days when a more conservative method was employed in earlier studies. AODs are calculated when the air mass is less than six; that is, when the Sun's elevation is greater than 9.25{sup o}. The more inclusive cloud screen and the use of most of the daylight hours yield a data set that can be used to more faithfully represent the true aerosol climate for this site. The diurnal aerosol cycle is examined month-by-month to assess the effects of an aerosol climatology on the basis of infrequent sampling such as that from satellites.

  10. Climatology of aerosol optical depth in north-central Oklahoma: 1992–2008

    SciTech Connect

    Michalsky, Joseph; Denn, Frederick; Flynn, Connor; Hodges, Gary; Kiedron, Piotr; Koontz, Annette; Schlemmer, James; Schwartz, Stephen E.

    2010-04-13

    Aerosol optical depth (AOD) has been measured at the Atmospheric Radiation Measurement Program central facility near Lamont, Oklahoma, since the fall of 1992. Most of the data presented are from the multifilter rotating shadowband radiometer, a narrow-band, interference-filter Sun radiometer with five aerosol bands in the visible and near infrared; however, AOD measurements have been made simultaneously and routinely at the site by as many as three different types of instruments, including two pointing Sun radiometers. Scatterplots indicate high correlations and small biases consistent with earlier comparisons. The early part of this 16 year record had a disturbed stratosphere with residual Mt. Pinatubo aerosols, followed by the cleanest stratosphere in decades. As such, the last 13 years of the record reflect changes that have occurred predominantly in the troposphere. The field calibration technique is briefly described and compared to Langley calibrations from Mauna Loa Observatory. A modified cloudscreening technique is introduced that increases the number of daily averaged AODs retrieved annually to about 250 days compared with 175 days when a more conservative method was employed in earlier studies. AODs are calculated when the air mass is less than six; that is, when the Sun’s elevation is greater than 9.25°. The more inclusive cloud screen and the use of most of the daylight hours yield a data set that can be used to more faithfully represent the true aerosol climate for this site. The diurnal aerosol cycle is examined month-by-month to assess the effects of an aerosol climatology on the basis of infrequent sampling such as that from satellites.

  11. A Crustal Cross Section over the Central North Iberian Margin: New Insights into the Bay of Biscay Inverted Hyperextended Rift

    NASA Astrophysics Data System (ADS)

    Cadenas Martínez, P.; Fernandez Viejo, G.; Pulgar, J. A.; Minshull, T. A.

    2015-12-01

    The Bay of Biscay is a V-shape failed arm of the Atlantic rift which was opened during the Mesozoic and partially closed during the Alpine orogeny in the Cenozoic, when the convergence of the Iberian and European Plates drove to the formation of the Pyrenean-Cantabrian realm in the North Iberian peninsula. A complete crustal cross section through the central part of the North Iberian Margin, representing the southern margin of the Bay of Biscay, is presented here from the interpretation of a high quality deep seismic reflection profile together with boreholes and well logs, acquired for oil and gas exploration purposes. The studied segment of this margin includes a basement high so called Le Danois Bank, and the Asturian basin, one of the sedimentary basins developed during the Mesozoic extensional processes, which was subsequently inverted during the Alpine orogeny. Most of the compression seems to have taken place through uplift of the continental platform and slope and the formation of an accretionary wedge at the bottom of the slope, so it is still possible to elucidate both extensional and compressional features. The basin appears as an asymmetric bowl bounded by synsedimentary normal faults with a maximum thickness of about 6 s TWT, which has been estimated to be equivalent to about 7 km. Depth migration of the seismic profile has revealed the presence of a deeper trough, with a maximum thickness of 13. 5 km at its main depocenter, which closely resembles the sedimentary thickness proposed for other contemporaneous proximal basins. These results support the high degree of extension and the exhumation processes proposed for this margin, deduced from refraction velocities and from the upper crustal and mantle rocks dredged at the slopes of Le Danois High. They will bring new insights to, and further constraints on, geodynamical models for this margin, where the amount of shortening linked with Cenozoic compression and the role of the rift structure during the

  12. Glacitectonic rafting and associated deformation of mid-Pleistocene glacigenic sediments, near Central Graben, central North Sea; results of a 2D High-Resolution Geophysical Survey

    NASA Astrophysics Data System (ADS)

    Vaughan-Hirsch, David

    2013-04-01

    Glacitectonic rafts are defined as dislocated slabs of bedrock or unconsolidated sediments, transported from their original position by glacial action. These relatively thin, slab-like bodies feature transport distances ranging from tens of meters to hundreds of kilometers. They occur as either single rafts, or multiple stacked bodies associated with a variety of ice-pushed landforms. Internally, rafts frequently appear undeformed although at a larger scale, they may be folded or cut by shear zones and brittle faults. However, the processes leading to the detachment, transport and subsequent emplacement of the rafts remain uncertain. This work describes the results of a geophysical 2D seismic survey of thrust-bound glacitectonic rafts and associated deformation structures, occurring within mid-Pleistocene glacigenic sediments of the Central Graben, central North Sea. The total shortened length of the rafted section is 2.4km, comprising a series of nine discrete rafts which individually range from 235m to 1018m in length. The principle basal detachment occurs at the erosive contact between Aberdeen Ground Formation and overlying Ling Bank Formation. The ice-proximal (northern) limit of rafting is defined by the presence of a large-scale palaeo-channel oriented perpendicular to the direction of rafting, composed of sediments of the Ling Bank Formation and the Forth Formation. The observed deformation structures infer a mean tectonic direction of 178°, indicating that they are associated with an active glacial advance from the north. The resulting deformation creates a minimum lateral shortening throughout the observed sequence of 35%, typifying a strongly compressional regieme associated with rafting. Throughout the surveyed area, structurally younger rafts are found to be emplaced towards the south, compared to the structurally older rafts which are emplaced towards the south-east. This distinction is suggested to be caused by early rafts creating an obstacle to

  13. Bayesian Spatiotemporal Pattern and Eco-climatological Drivers of Striped Skunk Rabies in the North Central Plains

    PubMed Central

    Raghavan, Ram K.; Hanlon, Cathleen A.; Goodin, Douglas G.; Anderson, Gary A.

    2016-01-01

    Striped skunks are one of the most important terrestrial reservoirs of rabies virus in North America, and yet the prevalence of rabies among this host is only passively monitored and the disease among this host remains largely unmanaged. Oral vaccination campaigns have not efficiently targeted striped skunks, while periodic spillovers of striped skunk variant viruses to other animals, including some domestic animals, are routinely recorded. In this study we evaluated the spatial and spatio-temporal patterns of infection status among striped skunk cases submitted for rabies testing in the North Central Plains of US in a Bayesian hierarchical framework, and also evaluated potential eco-climatological drivers of such patterns. Two Bayesian hierarchical models were fitted to point-referenced striped skunk rabies cases [n = 656 (negative), and n = 310 (positive)] received at a leading rabies diagnostic facility between the years 2007–2013. The first model included only spatial and temporal terms and a second covariate model included additional covariates representing eco-climatic conditions within a 4km2 home-range area for striped skunks. The better performing covariate model indicated the presence of significant spatial and temporal trends in the dataset and identified higher amounts of land covered by low-intensity developed areas [Odds ratio (OR) = 3.41; 95% Bayesian Credible Intervals (CrI) = 2.08, 3.85], higher level of patch fragmentation (OR = 1.70; 95% CrI = 1.25, 2.89), and diurnal temperature range (OR = 0.54; 95% CrI = 0.27, 0.91) to be important drivers of striped skunk rabies incidence in the study area. Model validation statistics indicated satisfactory performance for both models; however, the covariate model fared better. The findings of this study are important in the context of rabies management among striped skunks in North America, and the relevance of physical and climatological factors as risk factors for skunk to human rabies transmission and

  14. Bayesian Spatiotemporal Pattern and Eco-climatological Drivers of Striped Skunk Rabies in the North Central Plains.

    PubMed

    Raghavan, Ram K; Hanlon, Cathleen A; Goodin, Douglas G; Davis, Rolan; Moore, Michael; Moore, Susan; Anderson, Gary A

    2016-04-01

    Striped skunks are one of the most important terrestrial reservoirs of rabies virus in North America, and yet the prevalence of rabies among this host is only passively monitored and the disease among this host remains largely unmanaged. Oral vaccination campaigns have not efficiently targeted striped skunks, while periodic spillovers of striped skunk variant viruses to other animals, including some domestic animals, are routinely recorded. In this study we evaluated the spatial and spatio-temporal patterns of infection status among striped skunk cases submitted for rabies testing in the North Central Plains of US in a Bayesian hierarchical framework, and also evaluated potential eco-climatological drivers of such patterns. Two Bayesian hierarchical models were fitted to point-referenced striped skunk rabies cases [n = 656 (negative), and n = 310 (positive)] received at a leading rabies diagnostic facility between the years 2007-2013. The first model included only spatial and temporal terms and a second covariate model included additional covariates representing eco-climatic conditions within a 4km2 home-range area for striped skunks. The better performing covariate model indicated the presence of significant spatial and temporal trends in the dataset and identified higher amounts of land covered by low-intensity developed areas [Odds ratio (OR) = 3.41; 95% Bayesian Credible Intervals (CrI) = 2.08, 3.85], higher level of patch fragmentation (OR = 1.70; 95% CrI = 1.25, 2.89), and diurnal temperature range (OR = 0.54; 95% CrI = 0.27, 0.91) to be important drivers of striped skunk rabies incidence in the study area. Model validation statistics indicated satisfactory performance for both models; however, the covariate model fared better. The findings of this study are important in the context of rabies management among striped skunks in North America, and the relevance of physical and climatological factors as risk factors for skunk to human rabies transmission and the

  15. P wave velocity of the uppermost mantle of the Rio Grande rift region of North Central New Mexico

    SciTech Connect

    Murdock, J.N.; Jaksha, L.H.

    1981-08-10

    A network of seismograph stations has operated in north-central New Mexico since 1975. The network is approximtely 200 by 300 km in size and encompasses the Rio Grande rift there. Several seismic refraction experiments have been reported in the literature for the region of the network and adjacent areas. Because all of the seismic refraction lines are unreversed, P/sub n/ velocities reported were mainly of the inverse travel time slope for the direction of the corresponding line. The values of the inverse slope for those studies range from 7.6 to 8.2 km/s. The purpose of our study is to estimate the P wave velocity of the uppermost mantle by using the time term method. First, we timed the P/sub n/ waves of strong signals from five explosions and eight shallow earthquakes recorded by the network. The main data set, which contains 87 time-distance pairs, was processed by using the time term method. The P/sub n/ velocity estimated by this method is 8.0 +- 0.1 km/s. To corroborate this estimate, we then processed 10 subsets of the main data set in the same way. Almost allof the solutions show velocities 7.9--8.1 km/s, in agreement with the velocity determined for the main data set. The station time terms of the main data set also are substantied, and they suggest that the base of the crust dips northward by a few degrees in the region of the survey. The smallest value reported by other investigators for the inverse slope (7.6 km/s) appears to be related to the dip. The normal P wave velocity of the uppermost mantle of north-central New Mexico places restrictions on thermal models of the rift. For instance, the results exlude the likelihood of a wide zone of asthenosphere at the base of the crust beneath the rift, but they do not exclude a narrow such zone.

  16. Mental health literacy among secondary school students in North and Central Uganda: a qualitative study

    PubMed Central

    Okello, Elialilia S.; Abbo, Catherine; Muhwezi, Wilson W.; Akello, Grace; Ovuga, Emilio

    2015-01-01

    Objectives There has been limited effort to explore young people’s perceptions about mental illness in Uganda. For mental health programs targeting young people to succeed, it is important to incorporate their understanding of mental illness, their perceptions about causes of mental illness and their attitudes about mentally ill people. The objective of this study was to explore the mental health of young people in secondary schools in Northern and Central Uganda. Subjects and Methods This was a qualitative study where 24 focus group discussions (FGDs) were held with young people in secondary schools. Respondents aged 14-24 years were purposively selected from 4 secondary schools in the two regions. During the FGDs, young people’s perceptions and understanding of three areas listed below were explored: meaning of mental health/mental illness; causes of mental illness and attitudes toward mental illness. Data management and analysis was done with the help of Atlas.ti, a-qualitative-analysis software. Thematic analysis approach was employed. Results FGD participants used concepts like a sound and normal mind, right thinking, normal behavior and normal thoughts to define mental health. Mental illness on the other hand was defined as loss of sense of reality, malfunctioning of the brain, impaired thinking and bizarre behavior. Young people attributed mental illness to; substance abuse (Marijuana, alcohol), witnessing traumatic events (seeing ones your relatives being killed, or being forced to participate in killing-frequently mentioned by young people in Northern Uganda); witch craft, effect of physical illness e.g. HIV/epilepsy, thinking too much, accidents and genetic explanations. They had mixed opinions about interacting with mentally ill individuals. Unpredictability and dangerousness were known to be a recurrent theme among people with negative views about mentally ill. Nonetheless, some FGD participants believed that the level of interaction with mentally

  17. InSAR Identifies Mine-Dewatering Associated Bedrock Compaction and Subsidence in North- Central Nevada

    NASA Astrophysics Data System (ADS)

    Katzenstein, K. W.; Bell, J. W.; Watters, R. J.

    2007-12-01

    During the last decade, InSAR has been used extensively for the delineation of aquifer-system response to heavy groundwater pumping. A number of studies have demonstrated the vastly improved spatial resolution afforded by InSAR relative to traditional surveying techniques in detecting groundwater-related effects, including subsidence. This has allowed for further understanding of the complexity of subsidence bowls and the role of secondary factors such as structure, aquifer material properties and other previously unforeseen factors. In the western U.S., ground subsidence related to mine dewatering is a common occurrence due to the very large volumes of water (as high as 100,000 acre-ft/yr) that are typically pumped in order to lower the local groundwater table to facilitate the excavation of open pit and underground mines. Several gold mines located along the Carlin Trend of Central Nevada have produced distinct InSAR-identified subsidence signals of greater aerial extent and magnitude than most municipal groundwater signals, including signals partly or entirely within bedrock. One signal in particular shows a minimum of 54 cm of cumulative dewatering related subsidence between June 1, 1992 and September 21, 2000. Our study has produced many (>50) interferograms, each covering different time intervals, allowing a better understanding of how the subsidence signal has evolved in response to varied pumping rates from dewatering wells. Since the spatial resolution of the InSAR is much better than that of the monitoring well locations, the complexity of the signal is better delineated. The aerial extent of the subsidence feature is impressive as it extends as far as 20 km away from the location of the extraction wells used for dewatering. The area of maximum subsidence correlates well with the area of maximum groundwater drawdown, however the subsidence signal extends well beyond (as much as 8-10 km) the observed groundwater drawdown pattern. This suggests a much

  18. The Shoal Arm Formation, north-central Newfoundland: Fe- and Mn-enriched sediments underlying black shales and flysch

    SciTech Connect

    Bruechert, V.; Delano, J.W.; Kidd, J.W.; William, S.F. . Dept. of Geological Sciences)

    1992-01-01

    The Middle Ordovician Shoal Arm Formation is located in the central volcanic belt of north-central Newfoundland and consists of a sequence of hematitic argillites overlain by grey cherts and then black shales directly underneath a late Ordovician/early Silurian flysch sequence. The hematitic argillites are enriched in Fe, Mn, Ni, Pb, and Co. Geochemically definable components within related lithologic groups were discriminated using principal component analysis and factor analysis. These procedures indicate the presence of (1) biogenic, (2) mixed detrital, (3) hydrothermal, and (4) Mn-carbonate components. The base of the hematitic part is marked by a sharp increase in the hydrothermal component, which then decreases stratigraphically upward. The Mn-carbonate component also decreases upwards, but persists up to the grey cherts. The clastic component changes from mixed mafic/pelagic clay-like detritus to Zr-, Nb- and Y-rich detritus in the top hematitic part. The grey cherts mark a transitional stage between the hematitic sediments (oxic) and the black shales (anoxic). The change to increasingly O[sub 2]-deficient conditions is explained by (a) an increase of biological productivity and related O[sub 2]-drain by C[sub org]-oxidation and/or (b) diachronous subsidence of the basin floor into a deep-water anoxic layer as a result of the loading of the basin floor by an approaching thrust stack. The similar stratigraphic sequence and geochemistry of the Middle Ordovician sediments in the Taconic Allochthon of New York State suggest that these processes also acted at other locations along the continental margin of the Iapetus Ocean. This uniformity may reflect the strong influence of the warm Middle Ordovician climate on the sediment facies or, alternatively, the control by the specific tectonic environment.

  19. Multiproxy, Cross-Biome Analysis Of Ecosystem Dynamics During Late-Glacial And Holocene Climatic Change In North-Central North America

    NASA Astrophysics Data System (ADS)

    Camill, P.; Umbanhowar, C. E.; Geiss, C. E.; Teed, R. E.; Dorale, J. A.; Lynch, J. A.

    2010-12-01

    Vegetation ecotones and lake ecosystem dynamics have the potential to change dramatically with rapid climate warming. We present data for 15 proxies from eight well-dated lake sediment cores documenting late glacial and Holocene changes in both terrestrial and lake processes across a latitudinal gradient in central North America spanning grassland, aspen parkland, boreal, and tundra biomes. Our goal was to examine the timing and magnitude of terrestrial and aquatic ecosystem proxies across known climatic gradients in space and time. Results indicate that fire and vegetation dynamics were influenced by how climate controlled the relative abundance of arboreal vs. herbaceous taxa. Fire severity was greatest during the Holocene Thermal Maximum (HTM, 8500-5000 BP) only in forest-dominated boreal and northern parkland landscapes. At the grassland-woodland border and tundra-woodland ecotones, fire severity peaked after the HTM, presumably during more mesic conditions that supported greater landscape productivity. Lake ecosystems differed across the latitudinal gradient, with warmer grassland lakes showing a potential shift from diatoms to cyanobacteria following HTM aridity, P inputs, N:P (molar) declines to < 5-15, and N limitation, leading to poor or negative overall correlations among biogenic silica, nutrients, and organic matter. At the northernmost parkland and boreal and tundra sites, there was no indication from the pollen, magnetics, grain size, TP, or N:P data of significant mineral transport to these lakes or shifts in lake stoichiometry at or following the HTM, suggesting that aridity was less severe in higher latitudes. Unlike the grassland sites, which may have experienced a state change in the plankton community from diatoms to cyanobacteria as a result of HTM mineral inputs, cyanobacteria probably played a smaller role in the northernmost parkland, boreal, and tundra sites because the strong positive correlations between organic matter and bSi (P < 0

  20. Seismic tomography of the area of the 2010 Beni-Ilmane earthquake sequence, north-central Algeria.

    PubMed

    Abacha, Issam; Koulakov, Ivan; Semmane, Fethi; Yelles-Chaouche, Abd Karim

    2014-01-01

    The region of Beni-Ilmane (District of M'sila, north-central Algeria) was the site of an earthquake sequence that started on 14 May 2010. This sequence, which lasted several months, was triggered by conjugate E-W reverse and N-S dextral faulting. To image the crustal structure of these active faults, we used a set of 1406 well located aftershocks events and applied the local tomography software (LOTOS) algorithm, which includes absolute source location, optimization of the initial 1D velocity model, and iterative tomographic inversion for 3D seismic P- and S-wave velocities (and the Vp/Vs ratio), and source parameters. The patterns of P-wave low-velocity anomalies correspond to the alignments of faults determined from geological evidence, and the P-wave high-velocity anomalies may represent rigid blocks of the upper crust that are not deformed by regional stresses. The S-wave low-velocity anomalies coincide with the aftershock area, where relatively high values of Vp/Vs ratio (1.78) are observed compared with values in the surrounding areas (1.62-1.66). These high values may indicate high fluid contents in the aftershock area. These fluids could have been released from deeper levels by fault movements during earthquakes and migrated rapidly upwards. This hypothesis is supported by vertical sections across the study area show that the major Vp/Vs anomalies are located above the seismicity clusters. PMID:25485193

  1. Increased wetness confounds Landsat-derived NDVI trends in the central Alaska North Slope region, 1985–2011

    NASA Astrophysics Data System (ADS)

    Raynolds, Martha K.; Walker, Donald A.

    2016-08-01

    Satellite data from the circumpolar Arctic have shown increases in vegetation indices correlated to warming air temperatures (e.g. Bhatt et al 2013 Remote Sensing 5 4229–54). However, more information is needed at finer scales to relate the satellite trends to vegetation changes on the ground. We examined changes using Landsat TM and ETM+ data between 1985 and 2011 in the central Alaska North Slope region, where the vegetation and landscapes are relatively well-known and mapped. We calculated trends in the normalized difference vegetation index (NDVI) and tasseled-cap transformation indices, and related them to high-resolution aerial photographs, ground studies, and vegetation maps. Significant, mostly negative, changes in NDVI occurred in 7.3% of the area, with greater change in aquatic and barren types. Large reflectance changes due to erosion, deposition and lake drainage were evident. Oil industry-related changes such as construction of artificial islands, roads, and gravel pads were also easily identified. Regional trends showed decreases in NDVI for most vegetation types, but increases in tasseled-cap greenness (56% of study area, greatest for vegetation types with high shrub cover) and tasseled-cap wetness (11% of area), consistent with documented degradation of polygon ice wedges, indicating that increasing cover of water may be masking increases in vegetation when summarized using the water-sensitive NDVI.

  2. Determinants of Cervical Cancer Screening Uptake among Women in Ilorin, North Central Nigeria: A Community-Based Study

    PubMed Central

    Idowu, Ajibola; Olowookere, Samuel Anu; Fagbemi, Aderonke Tolulope; Ogunlaja, Olumuyiwa Ayotunde

    2016-01-01

    Introduction. Cancer of the cervix is the leading cause of cancer deaths among women in developing countries. Screening is one of the most cost effective control strategies for the disease. This study assessed the determinants of cervical cancer screening uptake among Nigerian women. Methodology. This cross-sectional study was conducted using multistage sampling technique among 338 participants in Ilorin, North Central Nigeria. A pretested questionnaire was used for data collection and data analysis was done using SPSS version 21. Chi-square test was used for bivariate analysis while binary logistic regression was used for multivariate analysis. Statistical significance was set at p < 0.05. Results. Only 8.0% of the respondents had ever been screened for cancer of the cervix. The proportion of women who had ever been screened was significantly higher among those who demonstrated positive attitude to screening (81.5%, p = 0.001), respondents who were aware of the disease (100.0%, p = 0.001), and those who were aware of cervical cancer screening (88.9%, p = 0.001). Respondents who had negative attitude had 63% lesser odds of being screened compared to those who had positive attitudes towards screening (AOR; 0.37, 95% CI; 0.01–0.28). Conclusion. There is urgent need to improve the knowledge base and attitude of Nigerian women to enhance cervical cancer screening uptake among them. PMID:26880916

  3. Foods of American badgers in west-central Minnesota and southeastern North Dakota during the duck nesting season

    USGS Publications Warehouse

    Sovada, M.A.; Roaldson, J.M.; Sargeant, A.B.

    1999-01-01

    Although the American badger (Taxidea taxus) is common in grasslands and preys on a wide diversity of foods including birds, little is known about badger diet in areas where nesting ducks are common. Small mammals, primarily Muridae and Geomyidae, were the most common food items in the diet of badgers collected from west-central Minnesota and southeastern North Dakota during April-July 1987 through 1990, based on analysis of gastrointestinal tracts of 47 adult ( 1/4 -y-old) and 5 juvenile (<6-mo-old) badgers. Remains of mammals occurred in 98% of samples from adult badgers. Small quantities of insects were found in 40% of adult samples. Bird remains were in 32% of adult samples, most birds identified as Anatidae; ducks or ducklings occurred in 27% and duck eggs in 60% of those samples. Remains of reptiles, amphibians and mollusks were present, but were less common than other foods. Insects and bird eggs were more common during spring (April-May) than summer (June-July). Birds were more frequent in diets of adults than juvenile badgers.

  4. Thrust segment from the Antler orogeny identified north of the Snake River Plain, south-central Idaho

    SciTech Connect

    Skipp, B. )

    1993-04-01

    A small segment of folded thrust fault places silicified, cleaved, folded, graptolite-bearing black mudstone, sandstone, and minor granule conglomerate of the Ordovician Phi Kappa Formation over unnamed cleaved, yellow, calcareous siltstone and silty limestone of Devonian to Silurian age in the Long Canyon area near Fish Creek Reservoir, within a kilometer of the north-central margin of the Snake River Plain. The thrust fault and rocks of both hanging wall and footwall are overlain by sandy limestone and pebble conglomerate of the Middle Pennsylvanian Hailey Member of the Wood River Formation along a locally faulted unconformable contact. Thus, the age of the thrust is bracketed as post-Devonian and pre-Middle Pennsylvanian, a period that encompasses the Antler orogeny. The Long Canyon thrust fault is the first direct evidence of contraction within rocks of the postulated Mississippian Antler highland in western Idaho. Indirect evidence such as penetrative axial plane cleavage in Devonian argillites of the Milligen Formation, not present in younger argillites, has been recognized for several years. The entire sequence of Ordovician through Pennsylvanian rocks constitutes the southernmost exposure of the hanging wall of the Mesozoic Pioneer thrust fault system. In this area, the footwall of the Pioneer thrust comprises Silurian through Devonian platform carbonate rocks overlain unconformably by Mississippian orogenic detritus derived from the western Antler highland.

  5. Geologic Model for Oil and Gas Assessment of the Kemik-Thomson Play, Central North Slope, Alaska

    USGS Publications Warehouse

    Schenk, Christopher J.; Houseknecht, David W.

    2008-01-01

    A geologic model was developed to assess undiscovered oil and gas resources in the Kemik-Thomson Play of the Central North Slope, Alaska. In this model, regional erosion during the Early Cretaceous produced an incised valley system on the flanks and crest of the Mikkelsen High and formed the Lower Cretaceous unconformity. Locally derived, coarse-grained siliciclastic and carbonate detritus from eroded Franklinian-age basement rocks, Carboniferous Kekiktuk Conglomerate (of the Endicott Group), Lisburne Group, and Permian-Triassic Sadlerochit Group may have accumulated in the incised valleys during lowstand and transgression, forming potential reservoirs in the Lower Cretaceous Kemik Sandstone and Thomson sandstone (informal term). Continued transgression resulted in the deposition of the mudstones of the over-lying Cretaceous pebble shale unit and Hue Shale, which form top seals to the potential reservoirs. Petroleum from thermally mature facies of the Triassic Shublik Formation, Jurassic Kingak Shale, Hue Shale (and pebble shale unit), and the Cretaceous-Tertiary Canning Formation might have charged Thomson and Kemik sandstone reservoirs in this play during the Tertiary. The success of this play depends largely upon the presence of reservoir-quality units in the Kemik Sandstone and Thomson sandstone.

  6. Coastal and deltaic sedimentation of Upper Cretaceous Eagle Sandstone: relation to shallow gas accumulations, North-Central Montana

    SciTech Connect

    Rice, D.D.

    1980-03-01

    Depositional environments of the Upper Cretaceous Eagle Sandstone were studied at outcrops along the Missouri River and its southern tributaries from the town of Virgelle southeastward to the mouth of the Judith River in north-central Montana. The Eagle Sandstone is underlain by the Telegraph Creek Formation and overlain by the Claggett Shale, both of Late Cretaceous Age. The basal Virgelle was deposited along an eastwardly prograding coastal-interdeltaic mainland shoreline. The middle member of the Eagle represents coastal-plain deposition. The delta-front sandstone was deposited along a wave-dominated shoreline that prograded over a coastal plain following an overall marine transgression. The upper member lies disconformably on the middle member and is represented by rock types which were deposited in two distinct depositional settings. Interbedded sandstone, siltstone, and shale that exhibit variable bedding types in the northern outcrops probably accumulated in a tidal-flat environment. Natural gas from shallow accumulations in the Eagle Sandstone of the Bearpaw Mountains area is of biogenic origin and was probably generated in the surrounding shales during Late Cretaceous time. Although gravity-induced faults formed after the gas generation provide the final trapping mechanism, the initial control for entrapment was stratigraphic. Most of the early generated gas has remigrated into separate, discrete structural traps where porous reservoirs are developed; some of the gas may have been selectively sealed in origin stratigraphic traps. 16 figures, 1 table.

  7. Interactions between surface water and ground water and effects on mercury transport in the north-central Everglades

    USGS Publications Warehouse

    Harvey, Judson W.; Krupa, Steven L.; Gefvert, Cynthia; Mooney, Robert H.; Choi, Jungyill; King, Susan A.; Giddings, Jefferson B.

    2002-01-01

    The hydrology of the north-central Everglades was altered substantially in the past century by canal dredging, land subsidence, ground-water pumping, and levee construction. Vast areas of seasonal and perennial wetlands were converted to uses for agriculture, light industry, and suburban development. As the catchment area for the Everglades decreased, so did the sources of water from local precipitation and runoff from surrounding uplands. Partly in response to those alterations, water-resources managers compartmentalized the remaining wetlands in the north-central Everglades into large retention basins, called Water Conservation Areas (WCAs). In spite of efforts to improve how water resources are managed, the result has been frequent periods of excessive drying out or flooding of the WCAs because the managed system does not have the same water-storage capacity as the pre-drainage Everglades. Linked to the hydrological modifications are ecological changes including large-scale invasions of cattail, loss of tree islands, and diminishing bird populations in the Everglades. Complex interactions among numerous physical, chemical, and biological factors are responsible for the long-term degradation of the ecological character of the Everglades.Over the past 15 years, a new set of smaller wetland basins, called Stormwater Treatment Areas (STAs), have been designed and constructed by water-resources engineers on the former wetlands adjacent to WCAs. The purpose of STAs is to remove excess nutrients from agricultural drainage water prior to its input to WCAs. STAs tend to be about one-tenth the size of a WCA, and they are located on former wetlands on the northwestern side of WCAs on sites that were managed as farmland for much of the twentieth century in an area referred to as the Everglades Agricultural Area, or EAA. The objective of the present investigation was to quantify interactions between surface water and ground water in the Everglades Nutrient Removal Project

  8. Base-level Response to Holocene Climate Change in the Central Appalachian Mountains of North America: Preview of Global Warming?

    NASA Astrophysics Data System (ADS)

    Springer, G. S.; Rowe, H. D.; Cocina, F. G.; Hardt, B.; Cheng, H.; Edwards, R. L.

    2007-12-01

    Global Warming is expected to bring about substantive changes in global precipitation patterns, which will lead to altered stream hydrologies. The directions and magnitudes of streamflow changes can be inferred from climate projections, but changes in stream architecture and base level are open questions. We address base level response to climate change by reconstructing river behavior during the mid- to late Holocene, including the Hypsithermal when peak Holocene temperatures were achieved. We reconstruct the climate of the Greenbrier River watershed of the central Appalachian Mountains of North America using the stable isotope geochemistry of a stalagmite, cave sediments, and published pollen data. Independently, we construct a history of base level position using cave sediments deposited by the river. Stalagmite values of δ18O and δ13C are heavy during the Hypsithermal, which pollen results indicate was warm and dry compared to the rest of the Holocene. Cave sediments deposited by the Greenbrier River record base level as having been below the cave during the early and late Holocene, but above the cave during the Hypsithermal. The mid-Holocene base level rise is attributed to infilling of the channel with as much as 4 m of sediment, presumably a response to changes in storm frequency and stream hydrology. Global Warming will cause temperatures to exceed those of the Hypsithermal. Flood zones will extend to higher elevations and flood risks and vulnerabilities will increase dramatically if Appalachian rivers respond to Global Warming as the Greenbrier River did to the Hypsithermal.

  9. Models of marine transgression —Example from Lower Cretaceous fluvial and paralic deposits, north-central Kansas

    NASA Astrophysics Data System (ADS)

    Franks, Paul C.

    1980-01-01

    Transgression of the Early Cretaceous Kiowa sea in north-central Kansas led to deposition and preservation of fluvial, estuarine, and lagoon or bay deposits behind Kiowa barrier systems. The fluvial, estuarine, and part of the lagoon or bay deposits compose the Longford Member of the Kiowa Formation. The member is thickest in broad valleys that were eroded into Permian bed rock prior to deposition of the Cretaceous strata. Overlying Kiowa beds include open-sea deposits of shale., and barrier-system deposits of sandstone. Transgression was not accompanied by near-shore erosion of barrier, paralic, or fluvial deposits, nor by development of transgressive disconformities within the transgressive sequence, nor by deposition of transgressive sand sheets. Progradational pulses that might account for the generation and preservation of the barrier, paralic, and fluvial deposits are not apparent in the Longford-Kiowa record. An upward gradation from fluvial deposits at the base of the member to lagoonal deposits at the top and an apparently scattered distribution of Kiowa open-sea and barrier deposits above the member indicate that rising sea level or basin subsidence was accompanied by vertical growth, eventual submergence, and stepwise landward shift of barrier systems across expanding lagoons or bays. *Temporary address, until August 1980: c/o Amoco Production Company, P.O. Box 591, Tulsa, Oklahoma 74102

  10. Uranium and thorium enrichment in rocks from the base of DSDP Hole 465A, Hess Rise, central North Pacific

    USGS Publications Warehouse

    Hein, J.R.; Koski, R.A.; Morgenson, L.A.

    1982-01-01

    Uranium and thorium are concentrated in Cretaceous limestone, chert, ash, basalt, and other rock types at Deep Sea Drilling Project Site 465 located on the southern Hess Rise in the central North Pacific. U concentrations, up to 194 ppm on a carbonate-free basis, are among the highest recorded for any deep-sea deposits. U was initially derived from seawater and concentrated by absorption on terrigenous (humic) organic matter in limestone in a shallow marine environment. U and Th were probably concentrated further by low-temperature hydrothermal fluids emanating from the basaltic basement. Mainly montmorillonite, an alteration product of basalt and ash, and organic matter in sedimentary rocks acted as hosts for U and Th. The unique combination of sediments rich in humic organic matter, abundant smectite in altered ash and basalt, and warm hydrothermal solutions provided the necessary conditions for migration and concentration of U and Th. To better understand the conditions limiting the migrating and concentration of U and Th, other rocks deposited during the ocean-wide Cretaceous anoxic events should be analyzed for these elements. ?? 1982.

  11. Evaluation of surface water dynamics for water-food security in seasonal wetlands, north-central Namibia

    NASA Astrophysics Data System (ADS)

    Hiyama, T.; Suzuki, T.; Hanamura, M.; Mizuochi, H.; Kambatuku, J. R.; Niipele, J. N.; Fujioka, Y.; Ohta, T.; Iijima, M.

    2014-09-01

    Agricultural use of wetlands is important for food security in various regions. However, land-use changes in wetland areas could alter the water cycle and the ecosystem. To conserve the water environments of wetlands, care is needed when introducing new cropping systems. This study is the first attempt to evaluate the water dynamics in the case of the introduction of rice-millet mixed-cropping systems to the Cuvelai system seasonal wetlands (CSSWs) in north-central Namibia. We first investigated seasonal changes in surface water coverage by using satellite remote sensing data. We also assessed the effect of the introduction of rice-millet mixed-cropping systems on evapotranspiration in the CSSWs region. For the former investigation, we used MODIS and AMSR-E satellite remote sensing data. These data showed that at the beginning of the wet season, surface water appears from the southern (lower) part and then expands to the northern (higher) part of the CSSWs. For the latter investigation, we used data obtained by the classical Bowen ratio-energy balance (BREB) method at an experimental field site established in September 2012 on the Ogongo campus, University of Namibia. This analysis showed the importance of water and vegetation conditions when introducing mixed-cropping to the region.

  12. Comparison of clast and matrix dispersal in till: Charlo-Atholville area, north-central New Brunswick

    USGS Publications Warehouse

    Dickson, M.L.; Broster, B.E.; Parkhill, M.A.

    2004-01-01

    Striations and dispersal patterns for till clasts and matrix geochemistry are used to define flow directions of glacial transport across an area of about 800km2 in the Charlo-Atholville area of north-central New Brunswick. A total of 170 clast samples and 328 till matrix samples collected for geochemical analysis across the region, were analyzed for a total of 39 elements. Major lithologic contacts used here to delineate till clast provenance were based on recent bedrock mapping. Eleven known mineral occurrences and a gossan are used to define point source targets for matrix geochemical dispersal trains and to estimate probable distance and direction of transport from unknown sources. Clast trains are traceable for distances of approximately 10 km, whereas till geochemical dispersal patterns are commonly lost within 5 km of transport. Most dispersal patterns reflect more than a single direction of glacial transport. These data indicate that a single till sheet, 1-4 m thick, was deposited as the dominant ice-flow direction fluctuated between southeastward, eastward, and northward over the study area. Directions of early flow represent changes in ice sheet dominance, first from the northwest and then from the west. Locally, eastward and northward flow represent the maximum erosive phases. The last directions of flow are likely due to late glacial ice sheet drawdown towards the valley outlet at Baie des Chaleurs.

  13. Assessment of trophic dynamics of cephalopods and large pelagic fishes in the central North Atlantic Ocean using stable isotope analysis

    NASA Astrophysics Data System (ADS)

    Logan, John M.; Lutcavage, Molly E.

    2013-10-01

    Pelagic ecosystems in the central North Atlantic Ocean support numerous commercially-exploited tuna, shark, and billfish species, which rely largely on cephalopod as well as fish and crustacean prey. Carbon and nitrogen stable isotope analyses were performed on tuna and billfish predators as well as cephalopod prey species sampled during two research longline cruises (2001-02) to study their trophic structure. Nitrogen stable isotope (δ15N) analyses revealed similarity in trophic position (TP) among sampled fish predator species, with large swordfish occupying the highest TP. Species with wider vertical distributions (swordfish and bigeye tuna) had higher δ15N values than species more constrained to the epipelagic zone (yellowfin tuna and dolphinfish). Analysis of tissue nitrogen isotope values showed an ontogenetic increase for swordfish and white marlin but no effects for other sampled fish species. For cephalopods as a group, δ15N increased with size. Smaller cephalopods sampled in this study had δ15N values that were about one TP below co-occurring tunas and billfishes, confirming their importance as a prey resource. Larger cephalopods had similar δ15N values to tunas and billfishes, indicating that these large cephalopods occupy a comparable TP to their fish predators. Both carbon and nitrogen stable isotope values of large pelagic fishes showed spatial gradients relative to conspecifics analyzed in coastal regions, which can be used to trace large scale movements.

  14. Feature Analysis of Ocean Waves in North Central Pacific Ocean Based ASAR Wave Spectral Data and Wave Model

    NASA Astrophysics Data System (ADS)

    Wang, Jichao; Zhang, Jie; Yang, Jungang; Meng, Junmin

    2013-01-01

    Directional Spectrum of the ocean waves could be obtained form Envisat advanced synthetic aperture radar (ASAR) wave spectral data. The wave model WAVEWATCH III (WW3) is applied to simulate the ocean wave field. Study area is 185°E-215°E and 15°N-30°N, time range is from 1 January 2008 to 31 December 2008. Based on ASAR and buoy data, the wave numerical simulation and assimilation of the north central Pacific Ocean is carried out. The validation and assessment of ASAR ocean wave spectra products is performed. The optimal interpolation (OI) algorithm is used in model WW3 for assimilating ASAR wave spectra data. Based on the result of the simulation and assimilation, mean waves direction (MWD), significant wave height (SWH) and mean wave period (MWP) are analysed. SWH and MWP are larger in winter and SWH reach to more than 2.5 meters. Seasonal change of SWH and MWP are significant.

  15. Characterization of Fusarium secorum, a new species causing Fusarium yellowing decline of sugar beet in north central USA.

    PubMed

    Secor, Gary A; Rivera-Varas, Viviana; Christ, Daniela S; Mathew, Febina M; Khan, Mohamed F R; Varrelmann, Mark; Bolton, Melvin D

    2014-01-01

    This study characterized a novel sugar beet (Beta vulgaris L.) pathogen from the Red River Valley in north central USA, which was formally named Fusarium secorum. Molecular phylogenetic analyses of three loci (translation elongation factor1α, calmodulin, mitochondrial small subunit) and phenotypic data strongly supported the inclusion of F. secorum in the Fusarium fujikuroi species complex (FFSC). Phylogenetic analyses identified F. secorum as a sister taxon of F. acutatum and a member of the African subclade of the FFSC. Fusarium secorum produced circinate hyphae sometimes bearing microconidia and abundant corkscrew-shaped hyphae in culture. To assess mycotoxin production potential, 45 typical secondary metabolites were tested in F. secorum rice cultures, but only beauvericin was produced in detectable amounts by each isolate. Results of pathogenicity experiments revealed that F. secorum isolates are able to induce half- and full-leaf yellowing foliar symptoms and vascular necrosis in roots and petioles of sugar beet. Inoculation with F. acutatum did not result in any disease symptoms. The sugar beet disease caused by F. secorum is named Fusarium yellowing decline. Since Fusarium yellowing decline incidence has been increasing in the Red River Valley, disease management options are discussed. PMID:25209635

  16. Three-dimensional Effects and Shortwave Cloud Radiative Forcing Associated with Shallow Cumuli Over Central North America

    SciTech Connect

    Berg, Larry K.; Kassianov, Evgueni I.; Long, Charles N.; Mills, Jr., David

    2009-09-30

    Shallow cumuli are ubiquitous over large areas of the globe, including both the interior of continents and the trade wind regions over the oceans. Measurements made at the Atmospheric Radiation Measurement (ARM) Climate Research Facility, located in central North America, provide a unique long-term data set that can be used to investigate the influence that these clouds have on the shortwave surface energy budget at a continental location. Using data collected for the summers of 2000 through 2007, inclusive, over 900 hours with fair-weather cumuli were identified using data from a Total Sky Imager, cloud-radar and lidar. Data from a suite of surface radiometers was used to determine the shortwave forcing. This analysis estimates the three-dimensional effects of shallow cumuli by examining the occurrences of both positive and negative shortwave forcing. We show that the average surface shortwave forcing is approximately -45.5 W m-2. When the data are adjusted to account for periods without shallow clouds, the shortwave forcing over the entire summer (defined as May through August) are reduced in magnitude, with forcings of -2.1 W m-2.

  17. Three-dimensional effects and shortwave cloud radiative forcing associated with shallow cumuli over the central North America

    NASA Astrophysics Data System (ADS)

    Berg, Larry K.; Mills, David, Jr.; Kassianov, Evgueni I.; Long, Charles N.

    2009-09-01

    Shallow cumuli are ubiquitous over large areas of the globe, including both the interior of continents and the trade wind regions over the oceans. Measurements made at the Atmospheric Radiation Measurement (ARM) Climate Research Facility, located in central North America, provide a unique long-term data set that can be used to investigate the influence that these clouds have on the shortwave surface energy budget at a continental location. Using data collected for the summers of 2000 through 2007, inclusive, over 900 hours with fair-weather cumuli were identified using data from a Total Sky Imager, cloud-radar and lidar. Data from a suite of surface radiometers was used to determine the shortwave forcing. This analysis estimates the three-dimensional effects of shallow cumuli by examining the occurrences of both positive and negative shortwave forcing. We show that the average surface shortwave forcing is approximately -45.5 W m-2. When the data are adjusted to account for periods without shallow clouds, the shortwave forcing over the entire summer (defined as May through August) are reduced in magnitude, with forcings of -2.1 W m-2.

  18. [Spatial-temporal dynamics of red tide precursor organisms at the Pacific coast of North and Central America].

    PubMed

    Sierra-Beltrán, A P; Lluch-Cota, D B; Lluch-Cota, S E; Cortés-Altamirano, R; Cortés-Lara, M C; Castillo-Chávez, M; Carrillo, L; Pacas, L; Víquez, R; García-Hansen, I

    2004-09-01

    The Pacific coast of Central and North America has long been and still is impacted by the flourishing of microalgal populations known as Harmful Algal Blooms (HABs). The organisms that have caused recent HABs episodes in the region are among others, Gymnodinium catenatum, Pyrodinium bahamense var. compressum, and recently Cochlodinium cf. catenatum. In spite of the accumulated effects on the human health, the economic activities and the environment, scarce information is available on the subject. The augmented use of coastal zones for human activities is also paralleled by increased awareness of global climate changes. Thus, it is not an easy task to discriminate anthropogenic or natural phenomena, or both, as the major driving forces. The long-term data sets available for limited regions, as well as some sporadic observations during notorious blooms, allowed us to discriminate major changes in the biodiversity and biogeography of HAB organisms. Main changes refer to number of events, covered area, duration and frequency, number of blooming species and appearance of not previously reported harmful taxa. The variables more clearly related to these dynamic phenomena, seems to be sea surface temperature and wind force, but it is not yet possible to weight their contributions. The participation of rain is not fully evaluated to date. The collaborative communication among small-budget monitoring operations in the region allowed to "pass the voice" about peaking concentrations of HAB organisms, diminishing the risk of poisoning. PMID:17465122

  19. North-striking fault zones and evolution of the central graben, Ore-Ida graben, Malheur County, Oregon

    SciTech Connect

    Cummings, M.L.; Ebeling, C.; Johnson, A.G. . Dept. of Geology)

    1993-04-01

    The N-striking Wall Rock Ridge (WRR) and Dry Creek Buttes (DCB) fault zones play key roles in the evolution of the middle Miocene central graben within the Ore-Ida graben. Each zone contains closely spaced N-striking faults. Drag folds and overturned beds occur where Ne- and NW-striking faults converge with N-striking faults. During volcaniclastic sedimentation, vents for basalt hydrovolcanic centers were controlled by these structures. Control is exerted during repeated development of small-scale basins in which the Deer Butte Formation accumulated. The zones also control the distribution of dacite plugs, basalt and andesite sills. The vents for the 12.6 Ma Kern Basin Tuff at the base of the Grassy Mountain Formation occur within the DCBFZ. Northward projection passes through the Double Mountain. The fault zones are also important in formation of precious metal deposits. The Grassy Mountain prospect occurs within the Grassy Mountain Formation where it is cut by the DCBFZ. The Page prospect (Quartz Mountain) occurs within the Deer Butte Formation where it is cut by the WRRFZ. Red Butte, also within the Deer Butte Formation, occurs near the western edge of the DCBFZ. A 30-km gravity line on 200 m spacings was measured during 1992. The line crosses the WRRFZ south of Page Prospect and passes north of Red Butte before crossing the DCBFZ.

  20. Determinants of Cervical Cancer Screening Uptake among Women in Ilorin, North Central Nigeria: A Community-Based Study.

    PubMed

    Idowu, Ajibola; Olowookere, Samuel Anu; Fagbemi, Aderonke Tolulope; Ogunlaja, Olumuyiwa Ayotunde

    2016-01-01

    Introduction. Cancer of the cervix is the leading cause of cancer deaths among women in developing countries. Screening is one of the most cost effective control strategies for the disease. This study assessed the determinants of cervical cancer screening uptake among Nigerian women. Methodology. This cross-sectional study was conducted using multistage sampling technique among 338 participants in Ilorin, North Central Nigeria. A pretested questionnaire was used for data collection and data analysis was done using SPSS version 21. Chi-square test was used for bivariate analysis while binary logistic regression was used for multivariate analysis. Statistical significance was set at p < 0.05. Results. Only 8.0% of the respondents had ever been screened for cancer of the cervix. The proportion of women who had ever been screened was significantly higher among those who demonstrated positive attitude to screening (81.5%, p = 0.001), respondents who were aware of the disease (100.0%, p = 0.001), and those who were aware of cervical cancer screening (88.9%, p = 0.001). Respondents who had negative attitude had 63% lesser odds of being screened compared to those who had positive attitudes towards screening (AOR; 0.37, 95% CI; 0.01-0.28). Conclusion. There is urgent need to improve the knowledge base and attitude of Nigerian women to enhance cervical cancer screening uptake among them. PMID:26880916

  1. Metagenomic assessment of the microbial diversity in ground pork products from markets in the North Central Region of South Korea.

    PubMed

    Koo, Ok-Kyung; Baker, Christopher A; Kim, Hyun-Jung; Park, Si Hong; Ricke, Steven C

    2016-09-01

    The purpose of this study was to characterize the microbial community in ground pork using molecular approaches. Forty six ground pork products were purchased from local stores in the north central area of South Korea. Aerobic plate counts varied 4.23 ± 5.14 × 10(5) CFU/g with the range between 5.00 × 10(3) and 1.85 × 10(6) CFU/g for ground pork samples. Four ground meat samples were further processed for metagenomic analysis. Pseudomonas species was the most relative abundant with a wide range occurring (1.72 to 77.7%) as part of the microbial genera in ground pork. Bacteria such as Carnobacterium, Yersinia, Photobacterium were also identified in ground pork. Despite the prominence of certain genera across all samples there was still extensive microbial diversity among ground pork products that originated from different slaughter houses and were processed in different markets. Such diversity indicates that designing interventions to extend shelf life may be hampered by the extensive variability in the microbial consortia associated with pork products. However, this diversity may be useful for developing microbial traceability signatures unique to a slaughter house or a particular market. PMID:27192496

  2. Genetic characterization and phylogenetic analysis of skunk-associated rabies viruses in North America with special emphasis on the central plains.

    PubMed

    Davis, Rolan; Nadin-Davis, Susan A; Moore, Michael; Hanlon, Cathleen

    2013-06-01

    Across North America the skunk acts as a reservoir for several rabies virus variants. Some of these variants are geographically restricted in range as is the case for the California skunk variant and two distinct variants present in Mexico. In contrast the North Central and South Central skunk rabies viruses are dispersed in overlapping ranges over large areas of the Midwestern region of the United States with the former extending into southern parts of the Canadian prairies. Despite this extensive range, there has been only very limited molecular characterization of these two viral variants. This study has examined the genetic diversity of the rabies viruses associated with North American skunks, with particular emphasis on the South Central skunk variant which was found to comprise three distinct geographically restricted groups of viruses that could in some cases be further sub-divided. The phylogenetic relationships of these groups and sub-groups allowed us to infer the likely direction of spread of these variants in some instances. Patterns of amino acid replacement of North American skunk-associated rabies viruses for both the nucleoprotein and glycoprotein products are also examined. These patterns reflect the virus phylogeny but no amino acid residues associated specifically with the skunk host were identified. PMID:23524137

  3. Variant-specific persistence of infections with human papillomavirus Types 31, 33, 45, 56 and 58 and risk of cervical intraepithelial neoplasia.

    PubMed

    Xi, Long Fu; Schiffman, Mark; Koutsky, Laura A; Hughes, James P; Hulbert, Ayaka; Shen, Zhenping; Galloway, Denise A; Kiviat, Nancy B

    2016-09-01

    In our previous study of the etiologic role of oncogenic human papillomavirus (HPV) types other than HPV16 and 18, we observed a significantly higher risk of cervical intraepithelial neoplasia Grades 2-3 (CIN2/3) associated with certain lineages of HPV types 31/33/45/56/58 [called high-risk (HR) variants] compared with non-HR variants. This study was to examine whether these intra-type variants differ in persistence of the infection and persistence-associated risk of CIN2/3. Study subjects were women who had any of HPV types 31/33/45/56/58 newly detected during a 2-year follow-up with 6-month intervals. For each type, the first positive sample was used for variant characterization. The association of reverting-to-negativity with group of the variants and CIN2/3 with length of positivity was assessed using discrete Cox regression and logistic regression, respectively. Of the 598 newly detected, type-specific HPV infections, 312 became undetectable during follow-up. Infections with HR, compared with non-HR, variants were marginally more likely to become negative [adjusted hazard ratio = 1.3; 95% confidence interval (CI), 0.9-1.8]. The adjusted odds ratio associating with the development of CIN2/3 was 3.0 (95% CI, 1.2-7.4) for persistent infections with HR variants for 6 months and 10.0 (95% CI, 3.8-38.0) for persistent infections with HR variants for 12-18 months as compared with the first positive detection of HR variants. Among women with non-HR variants, there were no appreciable differences in risk of CIN2/3 by length of positivity. Findings suggest that the lineage-associated risk of CIN2/3 was not mediated through a prolonged persistent infection, but oncogenic heterogeneity of the variants. PMID:27121353

  4. Three-dimensional attenuation structure of the Hikurangi subduction zone in the central North Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Eberhart-Phillips, Donna; Reyners, Martin; Chadwick, Mark; Stuart, Graham

    2008-07-01

    We use waveform data from 2708 earthquakes recorded by dense seismograph deployments in the central North Island of New Zealand to image the 3-D attenuation structure of the Hikurangi subduction zone, down to ca. 300 km depth. Attenuation images are obtained by determining the quality factor of P-waves Qp, using a t* inversion with a previously determined 3-D seismic velocity model. We have included limited frequency dependence for Qp, with Qp being frequency independent above 10 Hz, and having a frequency dependence of (f/10)0.5 below 10 Hz. The Qp images provide further constraint on the large-scale features associated with subduction and magmatism beneath the central North Island, and serve to refine interpretations of crust and upper mantle structure from Vp and Vp/Vs. The subducted plate is the most prominent feature in the Qp images. Its high Qp (900-1200) is consistent with the ca. 120 Myr old slab being relatively cold. Qp is better at resolving the slab than Vp. The coincidence of a strong gradient in Qp with the upper plane of the dipping seismic zone indicates that even below 75 km depth the upper envelope of seismicity provides a good estimate of the location of the plate interface. The mantle wedge is generally imaged as a relatively low Qp (<400) feature below 50 km depth. However, there are significant changes evident in the wedge along the strike of the subduction zone. The most pronounced low Qp in the mantle wedge occurs from ca. 50 to 85 km depth beneath the productive, rhyolite-dominated central segment of the Taupo Volcanic Zone, suggesting a close link between volcanism and low Qp in the shallow mantle wedge. There is a strong correlation between low Qp, low Vp and high Vp/Vs in this part of the mantle wedge, suggesting that high temperature is the controlling influence on Qp there. Within 30 km of the surface of the slab, there is a large change in Qp but only a modest change in Vp. Our results are consistent with a fluid-rich, viscous

  5. Three-dimensional electrical resistivity of the north-central USA from EarthScope long period magnetotelluric data

    NASA Astrophysics Data System (ADS)

    Yang, Bo; Egbert, Gary D.; Kelbert, Anna; Meqbel, Naser M.

    2015-07-01

    We present initial results from three-dimensional inversion of long period EarthScope magnetotelluric (MT) transportable array data from 232 sites covering the north-central US. The study area covers the 1.1 Ga Mid-Continent Rift (MCR) system, which cuts across a series of Archean and Paleoproterozoic lithospheric blocks. The western arm of the MCR is clearly evident in shallow depth sections, with a narrow resistive core, flanked by elongate conductive basins. Other prominent upper-crustal features mapped include the moderately conductive Michigan and Illinois Basins, and extremely high conductivities in foreland basin rocks at the southern margin of the Superior craton. The most prominent conductive anomalies, in an otherwise relatively resistive mid-lower crust, are two elongate east-west oriented structures, which are closely aligned with previously inferred continental sutures. The first underlies the southern margin of the Superior craton just north of the Niagara Fault (NF), and can be associated with the ∼1.85 Ga Penokean Orogeny. A second, further south beneath Iowa and western Wisconsin, lies just south of the Spirit Lake tectonic zone (SLtz), and can be identified with Yavapai accretion at ∼1.75 Ga. Both of these conductive sutures are cleanly cut by the MCR, which is otherwise not clearly evident in the deeper parts of the resistivity model. The break in the anomalies is narrow, comparable to the surface expression of the MCR, indicating that rifting impacts on the entire crustal section were highly localized. Both suture-related anomalies are imaged as extending into, and perhaps through, the lithosphere as dipping diffuse zones of reduced mantle resistivity. Sense of dip of these structures (southward for the NF anomaly, northward for SLtz) agrees with previously inferred models for subduction and accretion, suggesting that a conductive phase (most likely carbon) has been thrust deep into the lower crust and uppermost mantle, providing a marker of

  6. Ozone-CO relationships in plumes carrying North American pollution and boreal biomass burning emissions through the central North Atlantic lower free troposphere

    NASA Astrophysics Data System (ADS)

    Honrath, R. E.; Owen, R. C.; Val Martín, M.; Reid, J. S.; Lapina, K.; Kleissl, J. P.; Fialho, P.

    2004-12-01

    North American anthropogenic activities and biomass burning are both significant sources of nitrogen oxides emissions. Recent studies have indicated changes in the NOx\\ to CO emission ratio in U.S. urban regions, and amplified response to global climate change in boreal regions is expected to result (and may already have resulted) in increased frequency of large boreal fires. The PICO-NARE mountaintop (2.2~km altitude) station in the Azores Islands is well situated to probe the overall impact of both processes on lower tropospheric O3\\ levels. Measurements made there during the summers of 2001--2003 have been analyzed to assess these impacts. The relationship between CO and O3\\ in North American pollution outflow was found to be significantly steeper than expected, with a slope (d[O3]/d[ CO]) averaging 1.0 ppbv/ppbv, implying significantly more ozone formation per unit CO emissions than observed in prior measurements over eastern North America and in the nearby downwind region. Potential reasons for this difference, including changes in eastern North American emissions of ozone precursors, airmass history, and NOx,y\\ export, will be discussed. In contrast to the moderate CO enhancements in North American outflow, we find that boreal fires in Siberia and North America result in the highest CO levels observed, produce ozone enhancements comparable to those in North American pollution outflow, and play a major role in interannual variability of CO. It has been suggested that the magnitude of boreal fires may be increasing as a result of changing boreal climate; these findings imply that such an increase could significantly impact hemispheric scale ozone, CO, and nitrogen oxides levels.

  7. Changes in ground-water levels in the Carlin Trend area, north-central Nevada, 1989-2003

    USGS Publications Warehouse

    Plume, Russell W.

    2005-01-01

    Ground-water pumpage in support of gold mining activities, including mine dewatering, has resulted in water-level declines and rises in different parts of the Carlin Trend area in north-central Nevada. Total annual pumpage at the Gold Quarry, Carlin, Genesis, and Betze Mines has ranged from about 5,000 acre-feet in 1989 to almost 130,000 acre-feet in 1994 and 1998. Excess water from the mines is stored in the TS Ranch and Maggie Creek Reservoirs. Aquifers in the Carlin Trend area are comprised of carbonate rocks of Cambrian to Permian age and basin-fill deposits and interbedded volcanic rocks of Tertiary and Quaternary age. Since 1992, water levels in carbonate-rock aquifers near the Gold Quarry Mine have declined as much as 680 feet below an elongate area 12 miles long and 6 miles wide northwest and southeast from the mine. Since 1990, water levels have declined by more than 1,600 feet in the deepest part of the cone of depression at the Betze Mine. The area encompassed by the main part of the cone, which is 7 miles long by 4 miles wide, did not change much during 1993-2003, although its depth had doubled. Near both mines, the cones of depression are bounded by faults acting as barriers to ground-water flow. Water levels in the volcanic rocks of northern Boulder Flat began to rise soon after the TS Ranch Reservoir began filling in 1990 because of infiltration. Since 1990, the net water-level rise around the reservoir has been 50 feet or more over an area of about 2 square miles, and 20 feet or more over an area of about 60 square miles. Since 1992, water levels in basin-fill deposits in Boulder Flat have risen 5 feet or more over an estimated area of 20 square miles as a result of (1) use of water from the Betze Mine as a substitute for irrigation pumpage, (2) water from the TS Ranch Reservoir infiltrating volcanic rocks and then flowing southward into adjacent basin-fill deposits, (3) secondary recharge of water from the mine for irrigating about 10,000 acres

  8. Fabric Characterization of Mantle beneath South Central North America: Constraints from Peridotite Xenoliths from Knippa and Kilbourne Hole

    NASA Astrophysics Data System (ADS)

    Satsukawa, T.; Michibayashi, K.; Raye, U.; Stern, R. J.; Anthony, E. Y.

    2009-12-01

    Knippa quarry and Kilbourne Hole are sites where we can study samples of the upper mantle beneath Texas and New Mexico. Knippa peridotite xenoliths are hosted by ~86 Ma nepehlinites of the Balcones Igneous Province in central Texas. Kilbourne Hole maar, Potrillo volcanic field (PVF) near El Paso, erupted basanite approximately 10 Ka ago and thus the xenoliths represent present-day thermal and compositional character of this segment of the continental mantle. Both provide rare snapshots of upper mantle processes and compositions beneath south-central Laurentia. The xenolith suites are dominated by lherzolite, harzburgite and dunite, although pyroxenites are also common at Kilbourne Hole. Temperatures determined using the Ca in opx thermometer (Brey and Kohler, 1990) range between 900 and 1000C. Kilbourne Hole peridotites are several types. Fine-grained lherzolite has the lowest temperatures, porphyroclastic lherzolite intermediate temperature, and harzburgite and dunite the highest temperature. Large olivine grains commonly contain subgrain boundaries. The dominant slip system in olivine was determined from the orientations of the axes of subgrain rotation and CPO data. Olivine CPO data show strong concentration in [100] and [100]{0kl} patterns in Knippa peridotites, and [100](010) and [010]-fiber patterns in Kilbourne peridotites. We interpret the development of [010]-fiber patterns to: (i) axial shortening or 3D transpressive deformation, (ii) activation of multiple glide directions, (iii) deformation in the presence of melt. Presence of melt is also indicated by xenolith elemental compositions, which indicate melt infiltration and reaction. CPO strength is characterized by the dimensionless texture index “J”. J-index of Knippa peridotites varies from 4.6 to 11.4. Kilbourne Hole peridotite J-indices positively correlate with temperature, varying from 5 to 10 for the low temperature lherzolite to an unusually high value of 20 for the harzburgite and dunite

  9. Gravity modeling constraints on the Gatun-Chagres Basin and tectonic evolution of north-central Panama

    NASA Astrophysics Data System (ADS)

    Mynhier, Kelci

    The Oligocene-Miocene collision between Panama and South America significantly influenced ocean currents, global climate, and species diversification. Intraplate deformation of the Panama Block also played an important role in the evolution of this tectonic system, but is not well understood. A high-resolution gravity survey, coupled with geologic observations, was conducted in north-central Panama to better constrain the processes responsible for the Isthmus' modern configuration. Approximately 110 gravity stations were collected from Colon to Nombre de Dios, Panama and merged with existing data. Subsequently, four 2.5-D gravity models were produced to constrain the geometry of the Gatun-Chagres Basin using different sedimentary densities (1.8, 2.0, and 2.2 g/cm 3) to produce a realistic range of basin thicknesses. Overall, models with an average basin density of 2.0 g/cm3 are most consistent with offshore seismic profiles and field evidence, suggesting basin thickness is ~3.0--3.5 km. Previous seismic reflection data and geochemical analyses of Miocene arc volcanic rocks delineate a zone of extension in the Panama Canal Region, and gravity analysis from this study supports this hypothesis. Field evidence of multiple NW-facing normal faults suggests that they separate the basin from uplifted arc basement rocks east of the Canal, resulting in a 60 mGal gravity gradient. Beneath the basin, gravity models indicate ~5--10 km of crustal thinning. 3-D reconstruction of the 2.5-D models show a northward thickening basin and two depocenters that correspond to the Rio Indio and Toro facies of the Chagres Formation. This analysis suggests two directional extension of the Gatun-Chagres Basin; an east-west direction corresponding to the initial formation of the basin, and a modern northwest-southeast direction. To the northeast, gravity modeling indicates that there is a ~150 m-thick, Cretaceous-Holocene sedimentary basin present from Portobelo to Nombre de Dios. Sedimentary

  10. Relation of watershed setting and stream nutrient yields at selected sites in central and eastern North Carolina, 1997-2008

    USGS Publications Warehouse

    Harden, Stephen L.; Cuffney, Thomas F.; Terziotti, Silvia; Kolb, Katharine R.

    2013-01-01

    Data collected between 1997 and 2008 at 48 stream sites were used to characterize relations between watershed settings and stream nutrient yields throughout central and eastern North Carolina. The focus of the investigation was to identify environmental variables in watersheds that influence nutrient export for supporting the development and prioritization of management strategies for restoring nutrient-impaired streams. Nutrient concentration data and streamflow data compiled for the 1997 to 2008 study period were used to compute stream yields of nitrate, total nitrogen (N), and total phosphorus (P) for each study site. Compiled environmental data (including variables for land cover, hydrologic soil groups, base-flow index, streams, wastewater treatment facilities, and concentrated animal feeding operations) were used to characterize the watershed settings for the study sites. Data for the environmental variables were analyzed in combination with the stream nutrient yields to explore relations based on watershed characteristics and to evaluate whether particular variables were useful indicators of watersheds having relatively higher or lower potential for exporting nutrients. Data evaluations included an examination of median annual nutrient yields based on a watershed land-use classification scheme developed as part of the study. An initial examination of the data indicated that the highest median annual nutrient yields occurred at both agricultural and urban sites, especially for urban sites having large percentages of point-source flow contributions to the streams. The results of statistical testing identified significant differences in annual nutrient yields when sites were analyzed on the basis of watershed land-use category. When statistical differences in median annual yields were noted, the results for nitrate, total N, and total P were similar in that highly urbanized watersheds (greater than 30 percent developed land use) and (or) watersheds with greater

  11. On the Development of Multi-Hazard Early Warning Networks: Practical experiences from North and Central America.

    NASA Astrophysics Data System (ADS)

    Mencin, David; Hodgkinson, Kathleen; Braun, John; Meertens, Charles; Mattioli, Glen; Phillips, David; Blume, Fredrick; Berglund, Henry; Fox, Otina; Feaux, Karl

    2015-04-01

    The GAGE facility, managed by UNAVCO, maintains and operates about 1300 GNSS stations distributed across North and Central America as part of the EarthScope Plate Boundary Observatory (PBO) and the Continuously Operating Caribbean GPS Observational Network (COCONet). UNAVCO has upgraded about 450 stations in these networks to real-time and high-rate (RT-GNSS) and included surface meteorological instruments. The majority of these streaming stations are part of the PBO but also include approximately 50 RT-GNSS stations in the Caribbean and Central American region as part of the COCONet and TLALOCNet projects. Based on community input UNAVCO has been exploring ways to increase the capability and utility of these resources to improve our understanding in diverse areas of geophysics including seismic, volcanic, magmatic and tsunami deformation sources, extreme weather events such as hurricanes and storms, and space weather. The RT-GNSS networks also have the potential to profoundly transform our ability to rapidly characterize geophysical events, provide early warning, as well as improve hazard mitigation and response. Specific applications currently under development with university, commercial, non-profit and government collaboration on national and international scales include earthquake and tsunami early warning systems and near real-time tropospheric modeling of hurricanes and precipitable water vapor estimate assimilation. Using tsunami early warning as an example, an RT-GNSS network can provide multiple inputs in an operational system starting with rapid assessment of earthquake sources and associated deformation which informs the initial modeled tsunami. The networks can then can also provide direct measurements of the tsunami wave heights and propagation by tracking the associated ionospheric disturbance from several 100's of km away as the waves approaches the shoreline. These GNSS based constraints can refine the tsunami and inundation models and potentially

  12. Reinterpretation of Paleoproterozoic accretionary boundaries of the north-central United States based on a new aeromagnetic-geologic compilation

    USGS Publications Warehouse

    Holm, D.K.; Anderson, R.; Boerboom, Terrence; Cannon, W.F.; Chandler, V.; Jirsa, M.; Miller, J.; Schneider, D.A.; Schulz, K.J.; Van Schmus, W. R.

    2007-01-01

    The Paleoproterozoic crust in the north-central U.S. represents intact juvenile terranes accreted to the rifted Archean Superior craton. A new tectonic province map, based on the interpretation of a new aeromagnetic compilation, published geologic maps, and recent geochronologic data, shows progressive accretion of juvenile arc terranes from ca. 1900-1600 Ma. Contrary to earlier models, geon 18 Penokean-interval crust is primarily confined to a ???2100 Ma tectonic embayment of the rifted Superior craton. The newly defined Spirit Lake tectonic zone, characterized by a sharp magnetic discontinuity that marks the southern limit of Archean and Penokean-interval rocks, is here interpreted to represent an eastern analog of the Cheyenne belt suture zone in southern Wyoming. South of this boundary, geon 17 Yavapai-interval rocks form the basement upon which 1750 Ma rhyolite and succeeding quartzite sequences were deposited. Substantial portions of the Penokean and Yavapai terranes were subsequently deformed during the 1650-1630 Ma Mazatzal orogeny. The northern boundary of the Mazatzal terrane is obscured by abundant 1470-1430 Ma "anorogenic" plutons that stitched the suture with the older Yavapai terrane rocks. These data reveal a progressive tectonic younging to the south as the Laurentian craton grew southward and stabilized during the Proterozoic. Late Mesoproterozoic rift magmatism produced pronounced geophysical anomalies, indicating strong, but localized crustal modification. In comparison to the western U.S., little tectonism has occurred here in the last 1 billion years, providing a uniquely preserved record of the Precambrian evolution of the continental U.S. lithosphere. ?? 2007 Elsevier B.V. All rights reserved.

  13. Mineral associations produced by sodic-calcic hydrothermal alteration in the Buffalo Mountain pluton, north-central Nevada

    SciTech Connect

    McBride, D. . Dept. of Geology and Geography)

    1993-03-01

    Sodic-calcic (Na-Ca) hydrothermal alteration is prevalent throughout Mesozoic-age arc igneous rocks in the western US. The middle Jurassic Buffalo Mountain pluton, located in north-central Nevada, contains particularly well developed Na-Ca metasomatism. The Buffalo Mountain pluton is composed of porphyritic syenite, quartz monzonite, small bordering stocks (which account for less than 1% of the pluton), and an extensive felsic dike swarm. Quartz monzonite intruded syenite and constitutes the majority of the surface area. Unaltered porphyritic syenite is composed of perthite, plagioclase, quartz, augite, hornblende, biotite, olivine, magnetite, and other minerals accounting for less than 1% of the rock. Unaltered quartz monzonite is an aggregate of K-feldspar, plagioclase, quartz, biotite, hornblende, and accessory minerals accounting for less than 1% of the rock. The dikes cut both phases of the total intrusive rock body and are closely related in space to zones of Na-Ca alteration. Alteration variably affects all igneous rock types and exists as both fracture-controlled and pervasive Na-Ca alteration. Sodic-calcic alteration resulted in the following mineral reactions: K-feldspar is replaced by chalky-colored plagioclase, and primary mafic minerals react to form pale green diopside or, less commonly, actinolite. Garnet, scapolite, and epidote are often spatially associated with Na-Ca altered rocks. The fact that Na-Ca alteration occurs most commonly in and around dikes suggests that they might have been the source of channel for fluid entry into the surrounding igneous rocks. Further study will seek to constrain the origins and pathways of Na-Ca fluids.

  14. Environmental control on water quality; cases studies from Battle Mountain mining district, north-central Nevada. Chapter A.

    USGS Publications Warehouse

    Tuttle, Michele L.W.; Wanty, Richard B.; Berger, Byron R.; Stillings, Lisa L.

    2003-01-01

    The environmental controls on water quality were the focus of our study in a portion of the Battle Mountain mining district, north-central Nevada. Samples representing areas outside known mineralized areas, in undisturbed mineralized areas, and in mined areas were chemically and isotopically analyzed. The results are related to geologic, hydrologic, and climatic data. Streams in background areas outside the mineralized zones reflect normal weathering of volcanically derived rocks. The waters are generally dilute, slightly alkaline in pH, and very low in metals. As these streams flow into mineralized zones, their character changes. In undisturbed mineralized areas, discharge into streams of ground water through hydrologically conductive fractures can be traced with chemistry and, even more effectively, with sulfur isotopic composition of dissolved sulfate. Generally, these tracers are much more subtle than in those areas where mining has produced adits and mine-waste piles. The influence of drainage from these mining relicts on water quality is often dramatic, especially in unusually wet conditions. In one heavily mined area, we were able to show that the unusually wet weather in the winter and spring greatly degraded water quality. Addition of calcite to the acid, metalrich mine drainage raised the stream pH and nearly quantitatively removed the metals through coprecipitation and (or) adsorption onto oxyhydroxides. This paper is divided into four case studies used to demonstrate our results. Each addresses the role of geology, hydrology, mining activity and (or) local climate on water quality. Collectively, they provide a comprehensive look at the important factors affecting water quality in this portion of the Battle Mountain mining district.

  15. Structural study of Wamba and Environs, north-central Nigeria using aeromagnetic data and NigeriaSat-X image

    NASA Astrophysics Data System (ADS)

    Ogunmola, J. K.; Gajere, E. N.; Ayolabi, E. A.; Olobaniyi, S. B.; Jeb, D. N.; Agene, I. J.

    2015-11-01

    Wamba 1:100,000 sheet 210 covers Wamba and Nassarawa Eggon area of North-Central Nigeria and consists of basement rocks, biotite granites and Older Granites in most parts of the northern part and by sedimentary rocks of the Cretaceous Middle Benue Trough in the southern part. High resolution aeromagnetic data was interpreted and the results integrated in a GIS environment with data from NigeriaSat-X image to map out the major structural trends within the area. Reduction-to-the-equator (RTE) operation was carried out on the aeromagnetic data after which several data transforms/derivatives such as horizontal derivative, analytical signal, and tilt derivative were calculated to highlight subsurface boundaries and the major structures within the area. Several digital image enhancement techniques such as general contrast stretching and edge enhancement were applied to the NigeraSat-X image in ERDAS IMAGINE 9.2 after which structures from the interpreted magnetic data and the image were mapped out on-screen using ArcMap 10. The results show that the RTE produced a reasonable geological picture of the area. Also the basement configuration consists of several NE-SW and NW-SE structures that range from 1 km to about 17 km in length with the NE-SW structures being the major trend within the area. The lineaments are mainly within the basement and the Older granites and may be related to the Pan-African Orogeny. This study was also able to map out more accurately the contact between the basement and the sediments hence a modified geological map of the area was produced.

  16. Evidence of evolving carbaryl resistance in western corn rootworm (Coleoptera: Chrysomelidae) in areawide-managed cornfields in north central Kansas.

    PubMed

    Zhu, K Y; Wilde, G E; Higgins, R A; Sloderbeck, P E; Buschman, L L; Shufran, R A; Whitworth, R J; Starkey, S R; He, F

    2001-08-01

    Susceptibility of adult populations of the western corn rootworm, Diabrotica virgifera virgifera LeConte, to carbaryl was determined by a survey in 1996 before the implementation of an areawide management program near Scandia in north central Kansas. Subsequently, the susceptibility of western corn rootworm adults to carbaryl has been monitored throughout the program from 1997 to 2000 in both control and managed areas. In 1996, adults were highly susceptible to carbaryl with a mean LC50 value of 0.64 microg/vial. This value was comparable to those for adults collected from other regions within Kansas. However, adult susceptibility to carbaryl decreased rapidly within the managed area, where the cucurbitacin- carbaryl-based bait SLAM has been used as the primary tool to control adults in this project since 1997. In 1999, adults collected from the managed area were 9- and 20-fold less susceptible to carbaryl at the LC50 and LC90 levels, respectively, than those evaluated in 1996. In contrast, adults collected from the control area were only 2- and 3-fold less susceptible to carbaryl at the LC50 and LC90 levels, respectively, than adults evaluated in 1996. Although field adult populations of western corn rootworm were relatively low in 2000, evaluations showed trends similar to those in 1999 regarding their carbaryl susceptibility in the managed and control areas. These results provide evidence that western corn rootworm has been evolving carbaryl resistance rapidly in response to the use of SLAM in areawide-managed cornfields near Scandia. PMID:11561854

  17. Hydrologic and Water Quality Assessment of Bioenergy Scenarios for the Boone River Watershed in North Central Iowa, U.S.

    NASA Astrophysics Data System (ADS)

    Gassman, P. W.

    2015-12-01

    he Boone River Watershed (BRW) is an intensively cropped region dominated by corn and soybean production that covers over 237,000 ha in north central Iowa. The BRW is reflective of both current Iowa cropping trends and elevated levels of nutrient pollution in streams. Nitrate losses are of particular concern, much of which escapes the cropland via subsurface tiles that drain the predominantly flat landscapes that characterize the watershed. Phosphorus export to stream systems in the BRW is also a problem of considerable concern. Questions have emerged as to the possible impacts of adopting cellulosic biofuel production systems in Iowa watersheds such as the BRW, which would be developed as function of corn stover removed after harvest or via the introduction of perennial biofuel crops such as switchgrass and miscanthus. In response, a modeling system been constructed for the watershed using the Soil and Water Assessment Tool (SWAT) model to address biofuel-related water quality and related issues. The specific version of SWAT (SWAT version 2012; Release 615) that is being used in the study features recent modifications made to the source code that corrected inaccuracies in previous codes in regards to simulating removal of corn stover and also the growth of switchgrass and miscanthus. In addition, updated crop growth parameters that more accurately represent the biomass production potential of switchgrass and miscanthus varieties being grown in the U.S. Corn Belt region are being used in this SWAT modeling system. The results of several scenarios are reported here that reflect future cellulosic biofuel scenarios based on 20%, 30% or 50% removal levels of corn stover or widespread adoption of switchgrass and/or miscanthus across much or all of the BRW. Both hydrologic and pollutant loss (sediment, nitrogen and phosphorus) losses are reported for all of the simulated scenarios.

  18. The Siberian loess record and its significance for reconstruction of Pleistocene climate change in north-central Asia

    NASA Astrophysics Data System (ADS)

    Chlachula, Jiří

    2003-09-01

    The Siberian loess represents the most significant terrestrial proxy record of Quaternary climatic history in northern Asia. Loess is extensive in southern Siberia, between the Irtysh Basin in the west and the Angara Basin in the east. Palaeoenvironmental multi-proxy data (magnetic susceptibility (MS), grain size, % CaCO 3, % TOC, pollen, etc.) from high-resolution loess-palaeosol sections provide evidence for a strongly fluctuating climatic sequence in north-central Asia during the Late Quaternary, displaying the globally diagnostic sequences found in the deep-sea oxygen isotope records. MS provides the most continuous and detailed record (encompassing the last two interglacial-glacial cycles) in loess sections in the Minusinsk Basin (Yenisei area) and on the northern Altai Plains. Evidence for periodic atmospheric shifts is provided by gradual changes in the main vegetation zones, with parkland-steppe and mixed taiga during warm interglacial/interstadial stages being replaced by boreal tundra-forest and arid periglacial tundra-steppe during stadials. Climatic pulses from warm intervals to cold are recorded by incipient (forest/steppe)-tundra gleysols. The occurrence of the highest sediment accumulation rates in glacial stages (OIS 4 and OIS 2) in the southern plains and depressions indicates that the most intensive aeolian dust deposition followed the glacial maxima, with the most recent interval dated to ca. 19-15 ka BP. Because of its zonal distribution and pronounced climatic continentality, the Siberian loess region represents an important data source for reconstructing past climates in the Northern Hemisphere. It provides a key to the correlation of other loess regions within the West-East Eurasian continental zone.

  19. Modeling a habitat suitability index for the eastern fall cohort of Ommastrephes bartramii in the central North Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Chen, Xinjun; Tian, Siquan; Liu, Bilin; Chen, Yong

    2011-05-01

    The eastern fall cohort of the neon flying squid, Ommastrephes bartramii, has been commercially exploited by the Chinese squid jigging fleet in the central North Pacific Ocean since the late 1990s. To understand and identify their optimal habitat, we have developed a habitat suitability index (HSI) model using two potential important environmental variables — sea surface temperature (SST) and sea surface height anomaly (SSHA) — and fishery data from the main fishing ground (165°-180°E) during June and July of 1999-2003. A geometric mean model (GMM), minimum model (MM) and arithmetic weighted model (AWM) with different weights were compared and the best HSI model was selected using Akaike's information criterion (AIC). The performance of the developed HSI model was evaluated using fishery data for 2004. This study suggests that the highest catch per unit effort (CPUE) and fishing effort are closely related to SST and SSHA. The best SST- and SSHA-based suitability index (SI) regression models were SISST-based = 0.7SIeffort-SST + 0.3 SICPUE-SST, and SISSHA-based = 0.5SIeffort-SSHA + 0.5SICPUE-SSHA, respectively, showing that fishing effort is more important than CPUE in the estimation of SI. The best HSI model was the AWM, defined as HSI=0.3SISST-based+ 0.7SISSHA-based, indicating that SSHA is more important than SST in estimating the HSI of squid. In 2004, monthly HSI values greater than 0.6 coincided with the distribution of productive fishing ground and high CPUE in June and July, suggesting that the models perform well. The proposed model provides an important tool in our efforts to develop forecasting capacity of squid spatial dynamics.

  20. Deposition of selenium and other constituents in reservoir bottom sediment of the Solomon River Basin, north-central Kansas

    USGS Publications Warehouse

    Christensen, Victoria G.

    1999-01-01

    The Solomon River drains approximately 6,840 square miles of mainly agricultural land in north-central Kansas. The Bureau of Reclamation, U.S. Department of the Interior, has begun a Resource Management Assessment (RMA) of the Solomon River Basin to provide the necessary data for National Environmental Policy Act (NEPA) compliance before renewal of long-term water-service contracts with irrigation districts in the basin. In May 1998, the U.S. Geological Survey (USGS) collected bottom-sediment cores from Kirwin and Webster Reservoirs, which are not affected by Bureau irrigation, and Waconda Lake, which receives water from both Bureau and non-Bureau irrigated lands. The cores were analyzed for selected physical properties, total recoverable metals, nutrients, cesium-137, and total organic carbon. Spearman's rho correlations and Kendall's tau trend tests were done for sediment concentrations in cores from each reservoir. Selenium, arsenic, and strontium were the only constituents that showed an increasing trend in concentrations for core samples from more than one reservoir. Concentrations and trends for these three constituents were compared to information on historical irrigation to determine any causal effect. Increases in selenium, arsenic, and strontium concentrations can not be completely explained by Bureau irrigation. However, mean selenium, arsenic, and strontium concentrations in sediment from all three reservoirs may be related to total irrigated acres (Bureau and non-Bureau irrigation) in the basin. Selenium, arsenic, and strontium loads were calculated for Webster Reservoir to determine if annual loads deposited in the reservoir were increasing along with constituent concentrations. Background selenium, arsenic, and strontium loads in Webster Reservoir are significantly larger than post-background loads.