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Sample records for north-end orebody rosebery

  1. The North End Boston.

    ERIC Educational Resources Information Center

    Connally, Nicole; And Others

    Goals and objectives, student activities, and evaluations are contained in this guide for a one-day scavenger hunt through the North End of Boston. The culmination of a unit involving urban planning and land-use problems, the field trip is intended to give students first-hand experience with city life and a better understanding of urban issues…

  2. Mine Planning for Asteroid Orebodies

    NASA Astrophysics Data System (ADS)

    Gertsch, L. S.; Gertsch, R. E.

    2000-01-01

    Given that an asteroid (or comet) has been determined to contain sufficient material of value to be potentially economic to exploit, a mining method must be selected and implemented. This paper discusses the engineering necessary to bring a mine online, and the opportunities and challenges inherent in asteroid mineral prospects. The very important step of orebody characterization is discussed elsewhere. The mining methods discussed here are based on enclosing the asteroid within a bag in some fashion, whether completely or partially. In general, asteroid mining methods based on bags will consist of the following steps. Not all will be required in every case, nor necessarily in this particular sequence. Some steps will be performed simultaneously. Their purpose is to extract the valuable material from the body of the asteroid in the most efficient, cost-effective manner possible. In approximate order of initiation, if not of conclusion, the steps are: 1. Tether anchoring to the asteroid. 2. Asteroid motion control. 3. Body/fragment restraint system placement. 4. Operations platform construction. 5. Bag construction. 6. Auxiliary and support equipment placement. 7. Mining operations. 8. Processing operations. 9. Product transport to markets.

  3. 25. DETAIL VIEW OF COMMEMORATIVE NAMEPLATE PLAQUE, NORTH END SPAN ...

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

    25. DETAIL VIEW OF COMMEMORATIVE NAMEPLATE PLAQUE, NORTH END SPAN - East Bloomsburg Bridge, Spanning Susquehanna River at Pennsylvania Route 487 (Legislative Route 283), Bloomsburg, Columbia County, PA

  4. 14. DETAIL VIEW OF COMMEMORATIVE PLAQUE AND FINIAL, NORTH END ...

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

    14. DETAIL VIEW OF COMMEMORATIVE PLAQUE AND FINIAL, NORTH END SPAN - East Bloomsburg Bridge, Spanning Susquehanna River at Pennsylvania Route 487 (Legislative Route 283), Bloomsburg, Columbia County, PA

  5. BLDG 1 REAR (EAST) AND NORTH END Naval Magazine ...

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

    BLDG 1 REAR (EAST) AND NORTH END - Naval Magazine Lualualei, Headquarters Branch, Administration Building, Between Constitution & Constellation Streets, east side of main quad, Pearl City, Honolulu County, HI

  6. 26. Aerial photograph dated 20 June 1942, showing north end ...

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

    26. Aerial photograph dated 20 June 1942, showing north end of Gould Island from the southwest. At upper left is firing pier. Shop building and power plant under construction at center. Photo courtesy of Naval Undersea Warfare Center, Division Newport, Rhode Island. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  7. 5. EXTERIOR OF NORTH END OF BUILDINT 104 SHOWING WOODSIDED ...

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

    5. EXTERIOR OF NORTH END OF BUILDINT 104 SHOWING WOODSIDED BEDROOM ADDITION TO FRONT OF HOUSE, AND SMALL GABLE ROOF OVER FORMER BATHROOM PROJECTION ON NORTH END OF HOUSE. VIEW TO SOUTH. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  8. 4. NORTH END OF TERMINAL ROOM, SHOP LEVEL SHOWING SPIRAL ...

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

    4. NORTH END OF TERMINAL ROOM, SHOP LEVEL SHOWING SPIRAL STAIR TO CABLE RACK. Looking north. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  9. Feature 6, removed culvert north end to south very little ...

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

    Feature 6, removed culvert north end to south very little showing due to vegetation - Victory Highway, One Mile Segment West of West Wendover and South of Interstate 80, West Wendover, Elko County, NV

  10. 6. NORTH END OF MACHINE SHOP. FORGE SHOP (HAER No. ...

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

    6. NORTH END OF MACHINE SHOP. FORGE SHOP (HAER No. CA-326-K) ON LEFT, FORD PLANT IN DISTANCE, NE BY 60. - Rosie the Riveter National Historical Park, Machine Shop, 1311 Canal Boulevard, Richmond, Contra Costa County, CA

  11. Looking South at North End of Rod Loading Line Including ...

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

    Looking South at North End of Rod Loading Line Including Welding Area Within Rod Loading building - Hematite Fuel Fabrication Facility, Rod Loading Building, 3300 State Road P, Festus, Jefferson County, MO

  12. 14. VIEW TO SOUTHWEST AT NORTH END OF SECONDFLOOR ASSEMBLY ...

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

    14. VIEW TO SOUTHWEST AT NORTH END OF SECOND-FLOOR ASSEMBLY AREA. VIEW SHOWS DETAILS OF SAWTOOTH ROOF STRUCTURE. - Rosie the Riveter National Historical Park, Ford Assembly Plant, 1400 Harbour Way South, Richmond, Contra Costa County, CA

  13. 1. WEST SIDE, NORTH END OF BUILDING 1. SHOWS ADDITIONAL ...

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

    1. WEST SIDE, NORTH END OF BUILDING 1. SHOWS ADDITIONAL ANGLES IN BUILDING AT SOUTHERN END. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  14. 3. SANDY RIVER BRIDGE AT TROUTDALE, NORTH END, LOOKING 184 ...

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

    3. SANDY RIVER BRIDGE AT TROUTDALE, NORTH END, LOOKING 184 DEGREES SOUTH. SAME PHOTO AS OR-36-2. - Historic Columbia River Highway, Sandy River Bridge at Troutdale, Historic Columbia River Highway spanning Sandy River, Troutdale, Multnomah County, OR

  15. 4. SANDY RIVER BRIDGE AT TROUTDALE, NORTH END, LOOKING 224 ...

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

    4. SANDY RIVER BRIDGE AT TROUTDALE, NORTH END, LOOKING 224 DEGREES SOUTHWEST. - Historic Columbia River Highway, Sandy River Bridge at Troutdale, Historic Columbia River Highway spanning Sandy River, Troutdale, Multnomah County, OR

  16. Interior view of north end of the Bagasse Storage Building ...

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

    Interior view of north end of the Bagasse Storage Building with traveling crane used to load bagasse to send to boiler, looking from the west - Kekaha Sugar Company, Bagasse Storage Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

  17. Oblique of north end and west side, brig is in ...

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

    Oblique of north end and west side, brig is in background to the right - U.S. Naval Base, Pearl Harbor, United States All-Steel Hangar, Wasp Boulevard between Kingfisher Street and Ranger Loop, Pearl City, Honolulu County, HI

  18. 5. EXTERIOR OF NORTH END OF BUILDING 105 SHOWING 1946 ...

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

    5. EXTERIOR OF NORTH END OF BUILDING 105 SHOWING 1946 BEDROOM ADDITION. BUILDING 108 IS VISIBLE AT EXTREME PHOTO LEFT. VIEW TO SOUTHEAST. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  19. 9. Interior of 'Pavilion Lounge' at north end of Second ...

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

    9. Interior of 'Pavilion Lounge' at north end of Second Grandstand, showing vaulted ceilings, bar and spider chandelier. (May 1993) - Longacres, Second Grandstand, 1621 Southwest Sixteenth Street, Renton, King County, WA

  20. 21. FOLDING DOORS AT RAIL SPUR ENTRANCE TO NORTH END ...

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

    21. FOLDING DOORS AT RAIL SPUR ENTRANCE TO NORTH END OF PLANT. VIEW TO EAST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  1. 20. OFFICE AT NORTH END OF SECOND FLOOR, ADMINISTRATIVE OFFICES ...

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

    20. OFFICE AT NORTH END OF SECOND FLOOR, ADMINISTRATIVE OFFICES SECTION. VIEW TO SOUTHEAST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  2. 23. LUNCH ROOM ALONGSIDE SUNKEN RAIL SPUR, NORTH END OF ...

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

    23. LUNCH ROOM ALONGSIDE SUNKEN RAIL SPUR, NORTH END OF PLANT. VIEW TO NORTH-NORTHEAST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  3. 6. INTERIOR DETAIL OF WINDOW IN EAST WALL NORTH END ...

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

    6. INTERIOR DETAIL OF WINDOW IN EAST WALL NORTH END ROOM. BUILDING 4 IS VISIBLE THROUGH WINDOW. - Chollas Heights Naval Radio Transmitting Facility, Recreation Building, 6410 Zero Road, San Diego, San Diego County, CA

  4. Detail, north end of console and pneumatic tube message port, ...

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

    Detail, north end of console and pneumatic tube message port, also showing mirror to reflect view of communications switchboard - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  5. 1. PERSPECTIVE VIEW OF THE NORTH END AND WEST SIDE, ...

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

    1. PERSPECTIVE VIEW OF THE NORTH END AND WEST SIDE, LOOKING SOUTHEAST FROM A BOAT. BUILDING NO. 14 IS VISIBLE AT THE EXTREME RIGHT. - United Engineering Company Shipyard, Pier 4, 2900 Main Street, Alameda, Alameda County, CA

  6. Interior detail of bathroom on first floor north end, west ...

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

    Interior detail of bathroom on first floor north end, west side, camera facing west. - Mare Island Naval Shipyard, WAVES Officers Quarters, Cedar Avenue, west side between Tisdale Avenue & Eighth Street, Vallejo, Solano County, CA

  7. 10. VIEW OF NORTH END SPAN, SHOWING FLOOR BEAM AND ...

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

    10. VIEW OF NORTH END SPAN, SHOWING FLOOR BEAM AND STRINGERS AT PANEL POINT L1 - East Bloomsburg Bridge, Spanning Susquehanna River at Pennsylvania Route 487 (Legislative Route 283), Bloomsburg, Columbia County, PA

  8. 8. VIEW, LOOKING SOUTHWEST, SHOWING NORTH END SPAN, SIDE AND ...

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

    8. VIEW, LOOKING SOUTHWEST, SHOWING NORTH END SPAN, SIDE AND FLOOR SYSTEM - East Bloomsburg Bridge, Spanning Susquehanna River at Pennsylvania Route 487 (Legislative Route 283), Bloomsburg, Columbia County, PA

  9. Detail, east side, north end, showing door and overhead rail ...

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

    Detail, east side, north end, showing door and overhead rail for refrigeration room. - Fitzsimons General Hospital, Ice Plant, Southwest Corner of East I Avenue & North Thirteenth Street, Aurora, Adams County, CO

  10. Detail, exterior side of doubleplanked north end, Burton Park Club ...

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

    Detail, exterior side of double-planked north end, Burton Park Club House, view to south-southwest (135mm lens). - Burton Park, Club House & Amphitheater, Adjacent ot south end of Chestnut Avenue, San Carlos, San Mateo County, CA

  11. Oblique view, north end and west side, Burton Park Club ...

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

    Oblique view, north end and west side, Burton Park Club House, view to south (90mm lens). - Burton Park, Club House & Amphitheater, Adjacent ot south end of Chestnut Avenue, San Carlos, San Mateo County, CA

  12. View of North End of Oxide Building Interior Including Roof ...

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

    View of North End of Oxide Building Interior Including Roof and Wall Juncture and Crane Trolley - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  13. J SERIES MAGAZINE. J 107 NORTH END AND REAR (EAST). ...

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

    J SERIES MAGAZINE. J 107 NORTH END AND REAR (EAST). J 106-103 IN BACKGROUND. - Naval Magazine Lualualei, Headquarters Branch, Inert Storehouse Type, Twelfth Street between Kwajulein & New Mexico Streets, Pearl City, Honolulu County, HI

  14. J SERIES MAGAZINE. #J107 FRONT (WEST) AND NORTH END. ...

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

    J SERIES MAGAZINE. #J107 FRONT (WEST) AND NORTH END. - Naval Magazine Lualualei, Headquarters Branch, Inert Storehouse Type, Twelfth Street between Kwajulein & New Mexico Streets, Pearl City, Honolulu County, HI

  15. 11. Detail view of the north end of the east ...

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

    11. Detail view of the north end of the east elevation highlighting the fluted tile door surround of the northeast entrance - Arlington Realty Building, 2300 North Wilson Boulevard, Arlington, Arlington County, VA

  16. 19. GENERAL VIEW OF EMPLOYEES' LOCKER ROOM AT NORTH END ...

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

    19. GENERAL VIEW OF EMPLOYEES' LOCKER ROOM AT NORTH END OF LEVEL 3; LOOKING NORTHWEST - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  17. 23. STEAM PLANT TURBINE DECK FROM NORTH END OF BUILDING, ...

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

    23. STEAM PLANT TURBINE DECK FROM NORTH END OF BUILDING, SHOWING FOURTH STEAM UNIT IN PLACE AT FAR SOUTH END. April 6, 1950 - Crosscut Steam Plant, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  18. 5. EXTERIOR ELEVATION OF NORTH END OF EAST FACADE OF ...

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

    5. EXTERIOR ELEVATION OF NORTH END OF EAST FACADE OF STEAM PLANT, BUILDING 740, LOOKING WEST. - Oakland Naval Supply Center, Steam Plant, Sixth Street south of East K Street, Oakland, Alameda County, CA

  19. 222. NORTH END OF DIVIDING STRIP LOCATED NEAR LITTLE HUNTING ...

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

    222. NORTH END OF DIVIDING STRIP LOCATED NEAR LITTLE HUNTING CREEK ON GWMP LOOKING SOUTH, 1946. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  20. 19. DETAIL, METAL LIGHT STANDARD, AT NORTH END BLOCK OF ...

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

    19. DETAIL, METAL LIGHT STANDARD, AT NORTH END BLOCK OF EAST PARAPET, FROM WEST, SHOWING SIMPLE ORNAMENTATION OF BASE OF STANDARD, WITH 'UNION METAL' IMPRINT - Fifth Street Viaduct, Spanning Bacon's Quarter Branch Valley on Fifth Street, Richmond, Independent City, VA

  1. BLDG A 101, FRONT (EAST) AND NORTH END SHOWING EXTERIOR ...

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

    BLDG A 101, FRONT (EAST) AND NORTH END SHOWING EXTERIOR STAIR TO 2ND FLOOR AND PALM TREE. - Naval Magazine Lualualei, Headquarters Branch, Operational Storage Building, Thirteenth Street near Franklin Street intersection, Pearl City, Honolulu County, HI

  2. 8. West side of north end of bridge resting on ...

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

    8. West side of north end of bridge resting on approach abutment. Oblique detail view northeast (from below roadbed level, beside bridge). 150 mm lens. - Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, Nevada County, CA

  3. 25. Aerial photograph dated 20 June 1942, showing north end ...

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

    25. Aerial photograph dated 20 June 1942, showing north end of Gould Island from the northeast (caption on photo is in error). Shop and power plant under construction at left, firing pier under construction at far right. Photo courtesy of Naval Undersea Warfare Center, Division Newport, Rhode Island. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  4. VIEW OF MACHINE SHOP STORAGE OPENINGS, NORTH END OF BARN, ...

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

    VIEW OF MACHINE SHOP STORAGE OPENINGS, NORTH END OF BARN, LOOKING SOUTH (This northern-most facade of the barn was originally a board and batten wall with two sliding doors. In the early decades of the twentieth century Frederick Edward Arnold moved the wall and doors; they now make up the north end of bay 3. This was done to ease machine storage) - Arnold Farm, Barn, 1948 Arnold Road, Coupeville, Island County, WA

  5. Interior, north end, upper level, looking south towards door to ...

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

    Interior, north end, upper level, looking south towards door to one of the building's refrigeration rooms. Photograph taken just south of CO-172-AQ-4. - Fitzsimons General Hospital, Ice Plant, Southwest Corner of East I Avenue & North Thirteenth Street, Aurora, Adams County, CO

  6. Interior, north end, upper level, looking west. This photograph taken ...

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

    Interior, north end, upper level, looking west. This photograph taken inside the refrigeration room whose door is in the background of CO-172-AQ-5. - Fitzsimons General Hospital, Ice Plant, Southwest Corner of East I Avenue & North Thirteenth Street, Aurora, Adams County, CO

  7. Interior, north end of building, looking north. At left is ...

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

    Interior, north end of building, looking north. At left is the threading machine and the cutout in the wall for a long tube in the machine is on the north wall beyond the machine. - Fitzsimons General Hospital, Shops Building, Northwest Corner of West Pennington Avenue, & North Tenth Street, Aurora, Adams County, CO

  8. 5. HOUSE NORTH END EXTERIOR SHOWING ASBESTOS SIDING, CONCRETE WALKWAY ...

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

    5. HOUSE NORTH END EXTERIOR SHOWING ASBESTOS SIDING, CONCRETE WALKWAY TO REAR OF HOUSE, CLOSELINE SUPPORT AT EXTREME PHOTO RIGHT, AND CASEMENT WINDOW TO ATTIC JUST BELOW THE GABLE PEAK. VIEW TO SOUTHWEST. - Big Creek Hydroelectric System, Big Creek Town, Operator House, Orchard Avenue south of Huntington Lake Road, Big Creek, Fresno County, CA

  9. 83. GENERAL VIEW FROM NORTH END OF GUN HILL PLATFORM ...

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

    83. GENERAL VIEW FROM NORTH END OF GUN HILL PLATFORM OF 3RD AVENUE EL SHOWING THE SOUTHBOUND TRACK APPROACH INTO GUN HILL STATION. 7TH AVENUE EXPRESS EL ABOVE. - Interborough Rapid Transit Company, Third Avenue Elevated Line, Borough of the Bronx, New York County, NY

  10. 6. VIEW OF NORTH END OF EAST DAM, LOOKING SOUTH. ...

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

    6. VIEW OF NORTH END OF EAST DAM, LOOKING SOUTH. (View is taken from lakeside with lowered water level. This view encompasses the same area as MT-88-A-5 above.) - Three Bears Lake & Dams, East Dam, North of Marias Pass, East Glacier Park, Glacier County, MT

  11. Facility 136, view of north end, "No Smoking" sign, view ...

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

    Facility 136, view of north end, "No Smoking" sign, view facing south-southwest - U.S. Naval Base, Pearl Harbor, Latrines, Off Avenue C, at Repair Basins B13, B15-B18 & B20, Pearl City, Honolulu County, HI

  12. DETAIL OF "FEET" OF MAIN TRUSS NORTH END. NOTE PLATES ...

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

    DETAIL OF "FEET" OF MAIN TRUSS NORTH END. NOTE PLATES ON WHICH FEET REST ALLOWING EXPANSION OF TRUSS AS IT EXPANDS AND SHRINKS UNDER THE SUN - Missouri & North Arkansas Railroad Bridge, Spanning Middle Fork Little Red River, Shirley, Van Buren County, AR

  13. 7. Oblique view southeast of north end of building. Scale ...

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

    7. Oblique view southeast of north end of building. Scale visible adjacent to door at lower right. Compare to HABS-CA-2611-B-4. - Deetjen's Big Sur Inn, Hayloft Building, East Side of State Highway 1, Big Sur, Monterey County, CA

  14. 12. VIEW OF THE NORTH END, STATION 'L', FROM THE ...

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

    12. VIEW OF THE NORTH END, STATION 'L', FROM THE ROOF OF POWERHOUSE EXTENSION (BUILDING L5), WELDING SHOP (BUILDING F) IN FOREGROUND, PEPCO BUILDING (BUILDING A) IN BACKGROUND - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  15. NORTH END OF DOUBLE FURNACE AND CAST AND ENGINE SHED, ...

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

    NORTH END OF DOUBLE FURNACE AND CAST AND ENGINE SHED, WITH BLOWER HOUSE TO THE EAST AND CHARGING BRIDGE AND TRESSLE TO THE WEST, LOOKING SOUTH-SOUTHEAST. - Tannehill Furnace, 12632 Confederate Parkway, Tannehill Historical State Park, Bucksville, Tuscaloosa County, AL

  16. 18. DETAIL OF NORTH END OF ATLAS CONTROL CONSOLE NEAR ...

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

    18. DETAIL OF NORTH END OF ATLAS CONTROL CONSOLE NEAR WEST WALL OF SLC-3W CONTROL ROOM SHOWING PAYLOAD ENVIRONMENT CONTROL AND MONITORING PANELS (LABELED 'PECMP') - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  17. 2. EXTERIOR NORTH END OF BUILDING 103 SHOWING PAVED PARKING ...

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

    2. EXTERIOR NORTH END OF BUILDING 103 SHOWING PAVED PARKING AREA BETWEEN BUILDING 103 AND BUILDING 104, AND WALKWAY TO FRONT (EAST SIDE) ENTRY OF HOUSE. VIEW TO SOUTHEAST. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  18. 1. EXTERIOR OVERVIEW OF NORTH END OF RUSH CREEK POWERHOUSE ...

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

    1. EXTERIOR OVERVIEW OF NORTH END OF RUSH CREEK POWERHOUSE RESIDENTIAL COMPLEX SHOWING BUILDING 108 AT PHOTO RIGHT AND BUILDING 105 AT PHOTO CENTER BEHIND SWITCHRACKS AND TREE. POWERHOUSE IS AT EXTREME PHOTO LEFT. VIEW TO WEST. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  19. 3. OVERVIEW LOOKING EAST: taken from north end BLDG. 1. ...

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

    3. OVERVIEW LOOKING EAST: taken from north end BLDG. 1. - Fafnir Bearing Plant, Bounded on North side by Myrtle Street, on South side by Orange Street, on East side by Booth Street & on West side by Grove Street, New Britain, Hartford County, CT

  20. 13. Concrete stairs at north end of east wall of ...

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

    13. Concrete stairs at north end of east wall of South Section, as viewed from floor of drydock. Depth measure on far left is same as in photo WA-116-E-12. Camera is pointed E. This photo makes a panorama with photo WA-116-E-3. - Puget Sound Naval Shipyard, Drydock No. 3, Farragut Avenue, Bremerton, Kitsap County, WA

  1. 16. EXTERIOR NORTH END OF TULE RIVER POWERHOUSE SHOWING POWERHOUSE ...

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

    16. EXTERIOR NORTH END OF TULE RIVER POWERHOUSE SHOWING POWERHOUSE AT PHOTO CENTER, SUBSTATION AT PHOTO RIGHT FOREGROUND, OFFICE BEHIND SUBSTATION AT RIGHT OF POWERHOUSE, AND MACHINE SHOP AT LEFT OF POWERHOUSE. THIS PHOTOGRAPH DUPLICATES HISTORIC VIEW SHOWN IN PHOTO CA-216-17. VIEW TO SOUTHEAST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA

  2. 1. EXTERIOR OVERVIEW OF NORTH END OF RUSH CREEK POWERHOUSE ...

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

    1. EXTERIOR OVERVIEW OF NORTH END OF RUSH CREEK POWERHOUSE RESIDENTIAL COMPLEX SHOWING BUILDING 108 AT PHOTO RIGHT AND BUILDING 105 AT PHOTO CENTER BEHIND TREE. RUSH CREEK POWERHOUSE IS PARTIALLY VISIBLE AT EXTREME PHOTO LEFT). VIEW TO WEST. - Rush Creek Hydroelectric System, Clubhouse Cottage, Rush Creek, June Lake, Mono County, CA

  3. 6. INTERIOR OF NORTH END OF STEAM PLANT, GROUND FLOOR, ...

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

    6. INTERIOR OF NORTH END OF STEAM PLANT, GROUND FLOOR, SHOWING FORMER LOCATION OF DIESEL ENGINES. THIS WAS THE FIRST PART OF THE BUILDING TO BE CONSTRUCTED, WHEN IT HOUSED ONLY THE DIESEL ENGINES. December 4, 1990 - Crosscut Steam Plant, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  4. Oblique view of north end and east side, taken from ...

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

    Oblique view of north end and east side, taken from back side of bus stop, with stair to Facility 2 in foreground, view facing southwest - U.S. Naval Base, Pearl Harbor, Passenger Shelter, Seventh Street near Avenue F intersection, Pearl City, Honolulu County, HI

  5. Facility 136, oblique view of east side and north end ...

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

    Facility 136, oblique view of east side and north end with entry door, electrical panel with soda bottles, view facing west - U.S. Naval Base, Pearl Harbor, Latrines, Off Avenue C, at Repair Basins B13, B15-B18 & B20, Pearl City, Honolulu County, HI

  6. Detail, north end wall, Burton Park Amphitheater, view to southwest ...

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

    Detail, north end wall, Burton Park Amphitheater, view to southwest (90mm lens). Also visible are pilasters along back wall, east wing of stage area (within doorway), and east steps. Walls are adobe brick, with concrete coping. - Burton Park, Club House & Amphitheater, Adjacent ot south end of Chestnut Avenue, San Carlos, San Mateo County, CA

  7. Detail, interior side of doubleplanked door, north end, Burton Park ...

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

    Detail, interior side of double-planked door, north end, Burton Park Club House, view to east-southeast (135mm lens). Note diagonal sheathing of interior surface, wrought-iron strap hinges. - Burton Park, Club House & Amphitheater, Adjacent ot south end of Chestnut Avenue, San Carlos, San Mateo County, CA

  8. View of plate girder spans at north end, looking west ...

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

    View of plate girder spans at north end, looking west from beneath state route 18 bridge (which lies along previous alignment of Pittsburgh, Fort Wayne & Chicago Railway). - Pittsburgh, Fort Wayne & Chicago Railway, Beaver River Bridge, Spanning Beaver River along line of Second Avenue, New Brighton, Beaver County, PA

  9. 62. May 1985. NORTH END OF WASH HOUSE (Negative slightly ...

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

    62. May 1985. NORTH END OF WASH HOUSE (Negative slightly reticulated. Tree behind fence is common fig, Ficus carica.) - Borough House, West Side State Route 261, about .1 mile south side of junction with old Garners Ferry Road, Stateburg, Sumter County, SC

  10. 55. Aerial view looking north; end of openwater section of ...

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

    55. Aerial view looking north; end of open-water section of Dundee Canal at bottom, Botany Worsted Mills at center - Dundee Canal Industrial Historic District, Beginning at George Street in Passaic & extending north along Dundee Canal approximately 1.2 miles to Canal headgates opposite East Clifton Avenue in Clifton, Passaic, Passaic County, NJ

  11. 18. John N. Vogel, Photographer, August 1992 NORTH END COUNTERWEIGHT ...

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

    18. John N. Vogel, Photographer, August 1992 NORTH END COUNTERWEIGHT PIT. VIEW TO EAST SOUTHEAST. STEP UP GEARS AT LEAST END OF MAIN DRIVE SHAFT GEAR (LOWER LEFT) - Tayco Street Bridge, Spanning Government Canal at Tayco & Water Streets, Menasha, Winnebago County, WI

  12. Detail of north end of the Electrical Shop (foreground) and ...

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

    Detail of north end of the Electrical Shop (foreground) and Sheet Metal Shop, note the metal-frame windows in the Electrical Shop, view facing east - Kahului Cannery, Plant No. 28, Boiler House, Sheet Metal and Electrical Shops, 120 Kane Street, Kahului, Maui County, HI

  13. Orebody Modelling for Exploration: The Western Mineralisation, Broken Hill, NSW

    SciTech Connect

    Lotfolah Hamedani, Mohammad Plimer, Ian Rutherford; Xu Chaoshui

    2012-09-15

    The Western Mineralisation in the Broken Hill deposit was studied to identify the zonation sequence of lithogeochemical haloes along and across the strike of the orebody. Samples used are from 77 drill holes and the samples were assayed for Pb, Zn, Fe, S, Cu, Ag, Cd, Sb, Bi and As. Variogram analyses were calculated for all the elements and kriging was used to construct the 3D block model. Analysis of cross sections along and across the strike of the orebody shows that Bi and Sb form broader halos around sulphide masses and this suggests that they are pathfinder elements for the Pb and Zn elements of this orebody. The threshold concentrations (minimum anomaly) of the 10 elements were determined using the concentration-area analysis. On east-west vertical cross sections, the values of linear productivity, variability gradient and zonality index were calculated for each element. Based on the maximum zonality index of each element, the sequence of geochemical zonation pattern was determined from top to bottom of the orebody. The result shows that S, Pb, Zn and Cd tend to concentrate in the upper part of the mineralisation whereas Ag, Cu, Bi and As have a tendency to concentrate in the lower part of the mineralised rocks. Also, an empirical product ratio index was developed based on the position of the elements in the zonation sequence. The methods and results of this research are applicable to exploration of similar Zn and Pb sulphide ore deposits.

  14. 31. VIEW OF DRILL HALL FROM NORTH END OF DRILL ...

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

    31. VIEW OF DRILL HALL FROM NORTH END OF DRILL FLOOR FACING SOUTH. SHOWS EAST AND WEST BALCONIES, VEHICLE ENTRANCE AT THE SOUTHWEST CORNER OF THE DRILL FLOOR, THE CONCESSION STAND IN THE SOUTHEAST CORNER OF THE DRILL FLOOR AND THE FOUR WINDOWS IN THE SOUTH TRUSS SPACE. NOTE CRACKS IN THE UPPER RIGHT CORNER (WEST) OF THE SOUTH WALL. - Yakima National Guard Armory, 202 South Third Street, Yakima, Yakima County, WA

  15. VIEW TO EAST OF THE NORTH END OF BASIN NO. ...

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

    VIEW TO EAST OF THE NORTH END OF BASIN NO. 1 (THE WESTERN-MOST BASIN) SHOWING THE CRANEWAY AND GALLERY BETWEEN BASINS NO. 1 AND 2. BASSWOOD BUOY TENDER AND THREE SMALL VESSELS ARE BERTHED IN BASIN NO. 1. LARGER VESSELS ARE BERTHED IN BASINS TO THE EAST, SEEN IN BACKGROUND - Rosie the Riveter National Historical Park, Graving Docks, Shipyard No. 3, Richmond, Contra Costa County, CA

  16. 7. WASTE CALCINING FACILITY, LOOKING AT NORTH END OF BUILDING. ...

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

    7. WASTE CALCINING FACILITY, LOOKING AT NORTH END OF BUILDING. CAMERA FACING SOUTH. TENT-ROOFED COVER IN RIGHT OF VIEW IS A TEMPORARY WEATHER-PROOFING SHELTER OVER THE BLOWER PIT IN CONNECTION WITH DEMOLITION PROCEDURES. SMALL BUILDING CPP-667 IN CENTER OF VIEW WAS USED FOR SUPPLEMENTARY OFFICE SPACE BY HEALTH PHYSICISTS AND OTHERS. INEEL PROOF SHEET NOT NUMBERED. - Idaho National Engineering Laboratory, Old Waste Calcining Facility, Scoville, Butte County, ID

  17. 5. Main Control Switchboard (north end rear), view to the ...

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

    5. Main Control Switchboard (north end rear), view to the south, with item 14 (the Libby transmission line panel) visible in left foreground, through item 9 (the Hot Springs No. 2 transmission line panel) obliquely visible on left side of the photograph. - Washington Water Power Clark Fork River Noxon Rapids Hydroelectric Development, Powerhouse, South bank of Clark Fork River at Noxon Rapids, Noxon, Sanders County, MT

  18. 1. Streetscape of north ends of Detention Wards, Building Nos. ...

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

    1. Streetscape of north ends of Detention Wards, Building Nos. 9946-B (left) and 9945-B (middle). Walled-in courtyard adjoins Building No. 9944-B at extreme right edge. Steam plant is in distance. This photo makes a panorama with photo WA-202-10-2. - Madigan Hospital, Detention Wards, Bounded by Wilson & McKinley Avenues & Garfield & Lincoln Streets, Tacoma, Pierce County, WA

  19. 11. PUMP ROOM FLOOR OF GENE PLANT FROM NORTH END, ...

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

    11. PUMP ROOM FLOOR OF GENE PLANT FROM NORTH END, CENTRIFUGAL PUMPS DESIGNED BY BYRON JACKSON CO., MANUFACTURED BY PELTON WATER WHEEL CO. OF SAN FRANCISCO. POWERED BY G.E. SYNCHRONOUS MOTOR 9000 HP, 6900 VOLTS, 612 AMPS, 7320 KVA, 3 PHASE, 60 CYCLES, 400 RPM, EXCITATION AT 125 VOLTS, 540 AMPS. - Gene Pump Plant, South of Gene Wash Reservoir, 2 miles west of Whitsett Pump Plant, Parker Dam, San Bernardino County, CA

  20. 2. CONTEXT VIEW LOOKING WEST AT THE NORTH END OF ...

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

    2. CONTEXT VIEW LOOKING WEST AT THE NORTH END OF BUILDING F, CENTER, SHOWING THE CORNER OF BUILDING D AT THE FAR RIGHT, AND THE NORTHWEST CORNER OF BUILDING AT THE FAR LEFT. BUILDING E IS VISIBLE BY THE PALM TREE AT RIGHT CENTER, JUST NORTH OF BUILDING F. - U.S. Coast Guard Air Station San Francisco, Warehouse, 1020 North Access Road, San Francisco, San Francisco County, CA

  1. The electromagnetic radiation from semiconductor minerals in orebody

    NASA Astrophysics Data System (ADS)

    Ozawa, M.; Nagahama, H.; Muto, J.; Nagase, T.

    2013-12-01

    In complex ore deposits composing semiconductor minerals, electromagnetic radiation in the radio frequency (30 kHz ~ 3 MHz) is induced by propagation of elastic waves [1]. Semiconductor minerals are divided into n- or p-type. When each p-type and n-type is joined, the resulting junction (p-n junction) has the rectifying property. Many natural orebodies show this property, but it has not been evaluated qualitatively. A lot of p-n junctions exist as which connect in parallel and in series in the orebody [2]. They can be regarded as a single p-n junction at large scale. Hence elucidating the electric property of micro p-n junction is required to understand the semiconductor properties of orebody. To discuss the electromagnetic emission from semiconductor minerals in the orebody associated with tectonic process, we measure the electric property of the semiconductor pyrite. Composition and electric properties of natural semiconductor minerals are heterogeneous due to the presence of impurities and defects. Therefore, it is needed to clarify the properties at each microscopic region. In this research, we apply electroetching method and SEM analysis to acquire composition characteristics and use an indentation probe to reveal microscopic electric properties. Sample of pyrite is from Waga-Sennin mine, Akita prefecture, Japan. The area of cross section is 1.4 cm2 with thickness of 0.38 mm2. In the electrolytic etching, the surface of samples showed etching figures and zonal structures with widths of about 10 -100 μm. According to the SEM analysis, Pb inclusions were observed to be precipitated parallel to crystallographic planes. The heterogeneous change in electric properties of each area was observed to be as etching figure. Thermal probing method clarified that the regions of n-p type differences were also coincidence well to etching figure patterns. P-type regions showed a higher solubility than n-type regions. At p-n junction regions, rectifying property was observed

  2. 1. EAST SIDE/NORTH END EXTERIOR OF RUSH CREEK POWERHOUSE SHOWING ...

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

    1. EAST SIDE/NORTH END EXTERIOR OF RUSH CREEK POWERHOUSE SHOWING ROLLING METAL DOOR ON NORTH END, SWITCHRACKS NORTH OF POWERHOUSE AND WORKER COTTAGES IN COMPLEX. VIEW TO SOUTHWEST. - Rush Creek Hydroelectric System, Powerhouse Exciters, Rush Creek, June Lake, Mono County, CA

  3. 1. 185/189D in center, north end west facades (190D front ...

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

    1. 185/189-D in center, north end west facades (190-D front left and west facade; 195-D rear right). Looking south. - D-Reactor Complex, Deaeration Plant-Refrigeration Buildings, Area 100-D, Richland, Benton County, WA

  4. Interior detail of sliding doors at north end U.S. ...

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

    Interior detail of sliding doors at north end - U.S. Naval Base, Pearl Harbor, United States All-Steel Hangar, Wasp Boulevard between Kingfisher Street and Ranger Loop, Pearl City, Honolulu County, HI

  5. Exterior detail of the north end double doors U.S. ...

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

    Exterior detail of the north end double doors - U.S. Naval Base, Pearl Harbor, Paint & Oil Storage, Near intersection of Avenue E & Seventh Street, adjacent to Facility Nos. 3A & 56, Pearl City, Honolulu County, HI

  6. Interior view from the north end entry U.S. Naval ...

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

    Interior view from the north end entry - U.S. Naval Base, Pearl Harbor, Paint & Oil Storage, Near intersection of Avenue E & Seventh Street, adjacent to Facility Nos. 3A & 56, Pearl City, Honolulu County, HI

  7. 51. VIEW OF NORTH END OF SLC3W UMBILICAL MAST IN ...

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

    51. VIEW OF NORTH END OF SLC-3W UMBILICAL MAST IN TRENCH WITH TRENCH DOORS OPEN. SLC-3W MST IN SERVICE POSITION OVER LAUNCHER IN BACKGROUND. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  8. 52. VIEW FROM NORTH END OF SLC3W MAST TRENCH SHOWING ...

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

    52. VIEW FROM NORTH END OF SLC-3W MAST TRENCH SHOWING NORTH FACE OF ERECT UMBILICAL MAST. LAUNCHER IN BACKGROUND. METEOROLOGICAL TOWER AND SLC-3E MST IN DISTANT BACKGROUND. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  9. MTR BUILDING INTERIOR, TRA603. CAMERA IS AT NORTH END OF ...

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

    MTR BUILDING INTERIOR, TRA-603. CAMERA IS AT NORTH END OF THIRD FLOOR BALCONY LOOKING SOUTHEAST. DETAIL OF REACTOR'S NORTH FACE AND ITS TEST HOLES. MOCK-UP APPARATUS IS BEYOND REACTOR. INL NEGATIVE NO. HD46-5-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  10. Progress report on geologic studies of the Ranger orebodies, Northern Territory, Australia

    USGS Publications Warehouse

    Nash, J.T.; Frishman, David

    1982-01-01

    The Ranger No. 1 and No. 3 orebodies contain about 124,000 tonnes U3O8 in highly chloritized metasediments of the lower Proterozoic Cahill Formation within about 500 m of the projected sub-Kombolgie Formation unconformity. In both orebodies, oxidized and reduced uranium minerals occur chiefly in quartzose schists that have highly variable amounts of muscovite, sericite, and chlorite. The effects of several periods of alteration are pervasive in the vicinity of orebodies where biotite and garnet are altered to chlorite, and feldspars to white mica or chlorite. Oxidized uranium minerals, associated with earthy iron oxides, occur from the surface to a depth of about 60 m. Below the oxidized zone, uranium occurs chiefly as uraninite and pitchblende disseminated through thick sections of quartz-chlorite-muscovite schist and has no apparent association with graphite or sulfides. In fact, graphite is rare and sulfides are generally low in abundance (<0.5 percent). Higher ore grades occur in disrupted zones a few centimeters thick and in some quartz-chlorite vein-like zones of uncertain origin. Uranium correlates strongly with chlorite, but not all of the many ages of chlorite have associated uranium. At least five textural varieties of chlorite are present and represent at least 3 ages. Preliminary microprobe analyses suggest that Mg-Fe-Al contents are relatively uniform. Apatite commonly occurs with chlorite. Uranium is not common in carbonate rocks and seems to occur only in disrupted zones that have chlorite alteration. Chloritization and silicification are more widespread and intense in the No. 1 orebody than in the No. 3. In both orebodies, hematite occurs tens to hundreds of meters below the weathered zone, in both altered and largely unaltered rocks, with and without uranium. The structure of the orebodies is outwardly simple, particularly in No. 3; dips are less than 40? on most lithologic contacts. The No. 1 orebody is in a basin-like structure about 400 m wide

  11. 46. NORTH END OF MILL NO. 2, 1st FLOOR, BELOW ...

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

    46. NORTH END OF MILL NO. 2, 1st FLOOR, BELOW PICKER AND CLOTH ROOM AREA. FUNCTION OF THIS SPACE UNKNOWN AT PRESENT. NOTE THAT EYE BEAM REPLACES ORIGINAL WALL OF 1892 PICKER HOUSE. CENTER (OR LEFT) DOOR IS ENTRY TO MILL NO. 2. RIGHT DOOR IS ENTRY TO 1892 NAPPER ROOM. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  12. MTR BUILDING INTERIOR, TRA603. CAMERA IS AT NORTH END OF ...

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

    MTR BUILDING INTERIOR, TRA-603. CAMERA IS AT NORTH END OF SECOND FLOOR BALCONY LOOKING TOWARDS WORK PLATFORMS ON NORTH FACE OF REACTOR. BRIDGE TO THIRD FLOOR BALCONY FROM TOP OF REACTOR IS AT UPPER RIGHT OF VIEW. CAMERA FACING EASTERLY. INL NEGATIVE NO. HD-46-4-1. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  13. MTR BUILDING INTERIOR, TRA603. CAMERA IS AT NORTH END OF ...

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

    MTR BUILDING INTERIOR, TRA-603. CAMERA IS AT NORTH END OF THIRD FLOOR BALCONY LOOKING SOUTHEAST AND ACROSS TOP OF REACTOR. MOCK-UP APPARATUS IS BEYOND REACTOR. BRIDGE CONNECTING BALCONY AND REACTOR TOP AT RIGHT OF VIEW. INL NEGATIVE NO. HD46-5-2. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  14. PROGRESS REPORT ON GEOLOGIC STUDIES OF THE RANGER OREBODIES, NORTHERN TERRITORY, AUSTRALIA.

    USGS Publications Warehouse

    Nash, J. Thomas; Frishman, David; ,

    1985-01-01

    The Ranger No. 1 and No. 3 orebodies contain about 124,000 tonnes U//3O//8 in highly chloritized metasediments of the lower Proterozoic Cahill Formation within about 500 m of the projected sub-Kombolgie Formation unconformity. In both orebodies, oxidized and reduced uranium minerals occur chiefly in quartzose schists that have highly variable amounts of muscovite, sericite, and chlorite. The effects of several periods of alteration are pervasive in the vicinity of orebodies where biotite and garnet are altered to chlorite, and feldspars to white mica or chlorite. Oxidized uranium minerals, associated with earthy iron oxides, occur from the surface to a depth of about 60 m. Below the oxidized zone, uranium occurs chiefly as uraninite and pitchblende disseminated through thick sections of quartz-chlorite-muscovite schist and has no apparent association with graphite or sulphides. The geologic age(s) of uranium emplacement are obscure because there are few age criteria. Reduced uranium minerals are younger than 1. 8-b. y. -old granite dykes, and some occur locally in 1. 65-b. y. -old Kombolgie Formation.

  15. Sampling and analysis of chemical element concentration distribution in rock units and orebodies

    NASA Astrophysics Data System (ADS)

    Agterberg, F. P.

    2012-01-01

    Existing sampling techniques applied within known orebodies, such as sampling along mining drifts, yield element concentration values for larger blocks of ore if they are extended into their surroundings. The resulting average concentration values have relatively small "extension variance". These techniques can be used for multifractal modeling as well as ore reserve estimation approaches. Geometric probability theory can aid in local spatial covariance modeling. It provides information about increase of variability of element concentration over short distances exceeding microscopic scale. In general, the local clustering of ore crystals results in small-scale variability known as the "nugget effect". Parameters to characterize spatial covariance estimated from ore samples subjected to chemical analysis for ore reserve estimation may not be valid at local scale because of the nugget effect. The novel method of local singularity mapping applied within orebodies provides new insights into the nature of the nugget effect. Within the Pulacayo orebody, Bolivia, local singularity for zinc is linearly related with logarithmically transformed concentration value. If there is a nugget effect, moving averages resulting from covariance models or estimated by other methods that have a smoothing effect, such as kriging, can be improved by incorporating local singularities indicating local element enrichment or depletion. Although there have been many successful applications of the multifractal binomial/p model, its application within the Pulacayo orebody results in inconsistencies, indicating some shortcomings of this relatively simple approach. Local singularity analysis and universal multifractal modeling are two promising new approaches to improve upon results obtained by commonly used geostatistical techniques and use of the binomial/p model. All methods in this paper are illustrated using a single example (118 Pulacayo zinc values), and several techniques are applied to

  16. Oreshoot zoning in the Carlin-type Betze orebody, Goldstrike Mine, Eureka County, Nevada

    USGS Publications Warehouse

    Peters, Stephen G.; Ferdock, Gregory C.; Woitsekhowskaya, Maria B.; Leonardson, Robert; Rahn, Jerry

    1998-01-01

    Field and laboratory investigations of the giant Betze gold orebody, the largest Carlin-type deposit known, in the north-central Carlin trend, Nevada document that the orebody is composed of individual high-grade oreshoots that contain different geologic, mineralogic, and textural characteristics. The orebody is typical of many structurally controlled Carlin-type deposits, and is hosted in thin-bedded, impure carbonate or limy siltstone, breccia bodies, and intrusive or calc-silicate rock. Most ores in the Betze orebody are highly sheared or brecciated and show evidence of syndeformational hydrothermal deposition. The interplay between rock types and pre- and syn-structural events accounts for most of the distribution and zoning of the oreshoots. Hydrothermal alteration is scale dependent, either in broad, pervasive alteration patterns, or in areas related to various oreshoots. Alteration includes decarbonatization (~decalcification) of carbonate units, argillization (illite-clay), and silicification. Patterns of alteration zoning in and surrounding the Betze orebody define a large porous, dilated volume of rock where high fluid flow predominated. Local restriction of alteration to narrow illite- and clay-rich selvages around unaltered marble or calc-silicate rock phacoids implies that fluid flow favored permeable structures and deformed zones. Gold mainly is present as disseminated sub-micron-sized particles, commonly associated with Asñrich pyrite, although one type of oreshoot contains micron-size free gold. Oreshoots form a three-dimensional zoning pattern in the orebody within a WNW-striking structural zone of shearing and shear folding, termed the Dillon deformation zone (DDZ). Main types of oreshoots are: (1) rutile-bearing siliceous oreshoots; (2) illite-clay-pyrite oreshoots; (3) realgar- and orpiment-bearing oreshoots; (4) stibnite-bearing siliceous oreshoots; and (5) polymetallic oreshoots. Zoning patterns result from paragenetically early development

  17. The development of volcanic hosted massive sulfide and barite gold orebodies on Wetar Island, Indonesia

    NASA Astrophysics Data System (ADS)

    Scotney, Philip M.; Roberts, Stephen; Herrington, Richard J.; Boyce, Adrian J.; Burgess, Ray

    2005-07-01

    Wetar Island is composed of Neogene volcanic rocks and minor oceanic sediments and forms part of the Inner Banda Arc. The island preserves precious metal-rich volcanogenic massive sulfide and barite deposits, which produced approximately 17 metric tonnes of gold. The polymetallic massive sulfides are dominantly pyrite (locally arsenian), with minor chalcopyrite which are cut by late fractures infilled with covellite, chalcocite, tennantite tetrahedrite, enargite, bornite and Fe-poor sphalerite. Barite orebodies are developed on the flanks and locally overly the massive sulfides. These orebodies comprise friable barite and minor sulfides, cemented by a series of complex arsenates, oxides, hydroxides and sulfate, with gold present as <10 μm free grains. Linear and pipe-like structures comprising barite and iron-oxides beneath the barite deposits are interpreted as feeder structures to the barite mineralization. Hydrothermal alteration around the orebodies is zoned and dominated by illite kaolinite smectite assemblages; however, local alunite and pyrophyllite are indicative of late acidic, oxidizing hydrothermal fluids proximal to mineralization. Altered footwall volcanic rocks give an illite K Ar age of 4.7±0.16 Ma and a 40Ar/39Ar age of 4.93±0.21 Ma. Fluid inclusion data suggest that hydrothermal fluid temperatures were around 250 270°C, showed no evidence of boiling, with a mean salinity of 3.2 wt% equivalent NaCl. The δ34S composition of sulfides ranges between +3.3‰ and +11.7‰ and suggests a significant contribution of sulfur from the underlying volcanic edifice. The δ34S barite data vary between +22.4‰ and +31.0‰, close to Miocene seawater sulfate. Whole rock 87Sr/86Sr analyses of unaltered volcanic rocks (0.70748 0.71106) reflect contributions from subducted continental material in their source region. The 87Sr/86Sr barite data (0.7076 0.7088) indicate a dominant Miocene seawater component to the hydrothermal system. The mineral deposits formed on

  18. The weathering of a sulfide orebody: Speciation and fate of some potential contaminants

    USGS Publications Warehouse

    Courtin-Nomade, A.; Grosbois, C.; Marcus, M.A.; Fakra, S.C.; Beny, J.-M.; Foster, A.L.

    2009-01-01

    Various potentially toxic trace elements such as As, Cu, Pb and Zn have been remobilized by the weathering of a sulfide orebody that was only partially mined at Leona Heights, California. As a result, this body has both natural and anthropogeni- cally modified weathering profiles only 500 m apart. The orebody is located in a heavily urbanized area in suburban Oakland, and directly affects water quality in at least one stream by producing acidic conditions and relatively high concentrations of dissolved elements (e.g., ??500 ??g/L Cu, ??3700 ??g/L Zn). Micrometric-scale mineralogical investigations were performed on the authigenic metal-bearing phases (less than 10 ??m in size) using electron-probe micro-analysis (EPMA), micro-Raman, micro X-ray absorption spectroscopy (??XAS), scanning X-ray diffraction ((??SXRD) and scanning X-ray fluorescence (??-SXRF) mapping techniques. Those measurements were coupled with classical mineralogical laboratory techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Authigenic metal-bearing phases identified are mainly sulfates (jarosite, epsomite, schwertmannite), Fe (oxy-)hydroxides (goethite, hematite and poorly crystalline Fe products) and poorly crystalline Mn (hydr-)oxides. Sulfates and Fe (oxy-)hydroxides are the two main secondary products at both sites, whereas Mn (hydr-) oxides were only observed in the samples from the non-mining site. In these samples, the various trace elements show different affinities for Fe or Mn compounds. Lead is preferentially associated with Mn (hydr-)oxides and As with Fe (oxy-)hydroxides or sulfates. Copper association with Mn and Fe phases is questionable, and the results obtained rather indicate that Cu is present as individual Cu-rich grains (Cu hydroxides). Some ochreous precipitates were found at both sites and correspond to a mixture of schwertmannite, goethite and jarosite containing some potentially toxic trace elements such as Cu, Pb and Zn. According to the trace

  19. THE WEATHERING OF A SULFIDE OREBODY: SPECIATION AND FATE OF SOME POTENTIAL CONTAMINANTS

    SciTech Connect

    Courtin-Nomade, Alexandra; Grosbois, Cecile; Marcus, Matthew A.; Fakra, Sirine C.; Beny, Jean Michel; Foster, Andrea L.

    2010-07-16

    Various potentially toxic trace elements such as As, Cu, Pb and Zn have been remobilized by the weathering of a sulfide orebody that was only partially mined at Leona Heights, California. As a result, this body has both natural and anthropogenically modified weathering profiles only 500 m apart. The orebody is located in a heavily urbanized area in suburban Oakland, and directly affects water quality in at least one stream by producing acidic conditions and relatively high concentrations of dissolved elements (e.g., {approx}500 mg/L Cu, {approx}3700 mg/L Zn). Micrometric-scale mineralogical investigations were performed on the authigenic metal-bearing phases (less than 10 {mu}m in size) using electron-probe micro-analysis (EPMA), micro-Raman, micro X-ray absorption spectroscopy (mXAS), scanning X-ray diffraction (mSXRD) and scanning X-ray fluorescence (mSXRF) mapping techniques. Those measurements were coupled with classical mineralogical laboratory techniques, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Authigenic metal-bearing phases identified are mainly sulfates (jarosite, epsomite, schwertmannite), Fe (oxy-)hydroxides (goethite, hematite and poorly crystalline Fe products) and poorly crystalline Mn (hydr-)oxides. Sulfates and Fe (oxy-)hydroxides are the two main secondary products at both sites, whereas Mn (hydr-) oxides were only observed in the samples from the non-mining site. In these samples, the various trace elements show different affinities for Fe or Mn compounds. Lead is preferentially associated with Mn (hydr-)oxides and As with Fe (oxy-)hydroxides or sulfates. Copper association with Mn and Fe phases is questionable, and the results obtained rather indicate that Cu is present as individual Cu-rich grains (Cu hydroxides). Some ochreous precipitates were found at both sites and correspond to a mixture of schwertmannite, goethite and jarosite containing some potentially toxic trace elements such as Cu, Pb and Zn. According to the

  20. Occurrence of Sn-Bearing colusite in the ore-body "T" of the Bor copper deposit, Serbia

    NASA Astrophysics Data System (ADS)

    Cvetković, Ljubomir; Pačevski, Aleksandar; Tončić, Trajče

    2013-07-01

    The ore body "T" is the newly discovered massive-pyrite type one which is located in the central part of the Bor copper mine. The main copper minerals are chalcocite-digenite, covellite and enargite. Small amounts of colusite are frequently present in the ore-body. It mostly occurs as the distinct exsolutions in digenite and, associating with enargite and covellite. Composition of the studied colusite shows enriched Sn content, giving an empirical formula from Cu24.7V1.8Fe0.2As5.1Sb0.2Sn0.8S32 to Cu26.7V2.0Fe0.3As3.0Sb0.3Sn3.5S32. This colusite represents a solid solution between colusite and nekrasovite within a range of 14-54 mol % nekrasovite. Most of the analyses show content of <50 mol % nekrasovite corresponding to the Sn-bearing colusite variety, while one analysis shows content of 54 mol % nekrasovite corresponding to the As-bearing nekrasovite.

  1. Rhenium-osmium systematics of the Mount Isa copper orebody and the Eastern Creek Volcanics, Queensland, Australia: implications for ore genesis

    NASA Astrophysics Data System (ADS)

    Gregory, Melissa J.; Schaefer, Bruce F.; Keays, Reid R.; Wilde, Andy R.

    2008-07-01

    The syn-tectonic breccia-hosted Mount Isa Cu deposit in northwest Queensland is the largest sediment-hosted Cu deposit in Australia. Whole-rock samples of chalcopyrite-rich Cu ore form an isochron with a Re-Os age of 1,372 ± 41 Ma. This age is more than 100 Ma younger than the previously accepted age of Cu ore formation, an Ar-Ar mineral age for biotite separated from the host rocks within the alteration envelope to the Cu orebody. This discrepancy cannot be unequivocally resolved due to a lack of other absolute geochronological constraints for Cu mineralisation or the deformation event associated with Cu emplacement. The 1,372 ± 41 Ma date may reflect (a) the time of Cu deposition, (b) the time of a hydrothermal event that reset the Re-Os signature of the Cu ore or (c) mixing of the Re-Os isotope systematics between the host rocks and Cu-bearing fluids. However, a range of published Ar-Ar and Rb-Sr dates for potassic alteration associated with Cu mineralisation also records an event between 1,350 and 1,400 Ma and these are consistent with the 1,372 Ma Re-Os age. The 1.8 Ga Eastern Creek Volcanics are a series of tholeiitic basalts with a primary magmatic Cu enrichment which occur adjacent to the Mount Isa Cu deposit. The whole-rock Os isotopic signature of the Eastern Creek Volcanics ranges from mantle-like values for the upper Pickwick Member, to more radiogenic/crustal values for the lower Cromwell Member. The Re-Os isotope signature of the Cu ores overlaps with those calculated for the two volcanic members at 1,372 Ma; hence, the Os isotope data are supportive of the concept that the Os in the Cu ores was sourced from the Eastern Creek Volcanics. By inference, it is therefore postulated that the Eastern Creek Volcanics are the source of Cu in the Mount Isa deposit, as both Os and Cu are readily transported by oxidised hydrothermal fluids, such as those that are thought to have formed the Cu orebody. The Pickwick Member yields a Re-Os isochron age of 1,833

  2. D-0 North End Cap Calorimeter Cold Test Results

    SciTech Connect

    Michael, J.; /Fermilab

    1990-08-02

    The North endcap calorimeter vessel was recieved on July 1, 1990. A cooldown of the pressure vessel with liquid nitrogen was performed on July 10-11 to check the vessel's integrity. With the pressure vessel cold, the insulating vacuum was monitored for leaks. Through out the testing, the insulating vacuum remained good and the vessel passed the test. The cold test was carried out per the procedures of D-Zero engineering note 3740.220-EN-250. The test was very similar to the cold test performed on the Central Calorimeter in October of 1987. Reference D-Zero engineering notes 3740.210-EN-122, 3740.000-EN107, and 3740.210-EN-110 for information about the CC cold test. The insulating vacuum space was pumped on while equipment was being connected to the pressure vessel. Two hours after starting to pump with the blower the vacuum space pressure was at about 210 microns. Pumping on the vacuum space for the next 15 hours showed no progress and a leak detector was connected to the pumping line. A leak check showed a leak in a thermocouple feedthru on the vacuum space relief plate. After fixing the leak, the pressure dropped to 16 microns in less than one hour. A rate of rise test was performed starting at a pressure of 13 microns. The pressure rose to 39 microns within 8 minutes and then only rose to 43 microns in 2.5 hours (1.6 microns/hour). After all connections were made to the pressure vessel, a vacuum pump with an estimated effective pumping speed of about 70 scfm was valved on. The lowest pressure achieved after 2 days of pumping was 80 microns. Valving out the pump for 30 minutes resulted in a 5 micron per minute rate of rise. The rate of rise was considered acceptable since there were known leak paths through the bolts of the signal ports. The EC North vessel was rolled outside of Lab A in preparation for a 5000 gallon liquid nitrogen trailer which arrived July, 10 at 8:00am. Before filling the vessel, the vacuum space pump was valved off. The pressure in the vacuum space was 12 microns at that point. During the next 24 hours of the test, the vacuum space pressure decreased to 5 microns. A plot of the vacuum space pressure with time is included at the end of this note. The liquid nitrogen was pressure transferred from the trailer at 29 psig to the pressure vessel at 1 psig for ten hours. At that time there was sufficient (16-inch) of liquid nitrogen in the vessel to turn the LN2 trailer delivery pump on. Thirteen and one half hours after starting the fill, the vessel had 50-inch of LN2 collected. During the latter part of the filling, about twelve loud metallic bangs were heard. The noises came at random intervals with sometimes five minutes between and other times an hour between. The best way to describe the sound is to imagine the sound made if someone was trapped inside the vessel with a baseball bat and took a good swing. The trailer was disconnected and the the vessel was left overnight for ten hours. Due to the slow LN2 fill rate, the temperature gradient in the pressure vessel shell was not very large, only about 25 kelvin difference was found from a RTD in the warm-up nozzle of the vessel and the resistors of the liquid level probe. A temperature versus time graph is included at the end of this note.

  3. North End Runway Material Extraction and Transport Environmental Assessment

    DTIC Science & Technology

    2006-05-01

    dust generated from mining and hauling operations. Whenever required by weather conditions, water would be used to decrease dust emissions from these...suppress dust emissions during dry weather , would be implemented. Dust from previous material extraction operations was not known to cause an impact to...Based on 12 hours of operation daily for each piece of equipment. ** (AP 42, 2005) . Whenever required by weather conditions, water would be used

  4. Geology of the north end of the Ruby Range, southwestern Montana

    USGS Publications Warehouse

    Tysdal, Russell G.

    1970-01-01

    This study consists of two parts: stratigraphy and sedimentation, and structure of rocks in the northern one-third of the Ruby Range of southwestern Montana. Detailed studies of Cambrian marine dolomite rocks in the Red Lion Formation and in the upper part of the Pilgrim Limestone resulted in their division into distinct rock units, termed lithofacies. These lithofacies contain features suggestive of subtidal, intertidal, and supratidal environments similar to those presently forming in the Persian Gulf. Stromatolltic structures occurring in the uppermost part of the Red Lion Formation are similar to those presently forming in Shark Bay, Australia. The Ruby Range within the map area is broken into a series of northwest-plunging basement (Precambrian metamorphic rock) blocks, differentially uplifted during the Cretaceous-Tertiary orogenic period. These blocks are bordered by upthrust faults, which are nearly vertical in their lower segments and are .low-angle in their uppermost parts. Asymmetrical folds in Paleozoic sedimentary rocks formed in response to the differential uplift of the blocks; thus they too plunge to the northwest. Displaced masses of rock border the range on the three sides within the map area and are interpreted as gravity-slide features resulting from uplift of the range. Normal faulting began blocking out the present range margins by Oligocene time.

  5. Geology of the north end of the Salt Valley Anticline, Grand County, Utah

    USGS Publications Warehouse

    Gard, Leonard Meade

    1976-01-01

    This report describes the geology and hydrology of a portion of the Salt Valley anticline lying north of Moab, Utah, that is being studied as a potential site for underground storage of nuclear waste in salt. Selection of this area was based on recommendations made in an earlier appraisal of the potential of Paradox basin salt deposits for such use. Part of sec. 5, T. 23 S., R. 20 E. has been selected as a site for subsurface investigation as a potential repository for radioactive waste. This site has easy access to transportation, is on public land, is isolated from human habitation, is not visible from Arches National Park, and the salt body lies within about 800 feet (244 m) of the surface. Further exploration should include investigation of possible ground water in the caprock and physical exploration of the salt body to identify a thick bed of salt for use as a storage zone that can be isolated from the shaly interbeds that possibly contain quantities of hydrocarbons. Salt Valley anticline, a northwest-trending diapiric structure, consists of Mesozoic sedimentary rocks arched over a thick core of salt of the Paradox Member of the Middle Pennsylvanian Hermosa Formation. Salt began to migrate to form and/or develop this structure shortly after it was deposited, probably in response to faulting. This migration caused upwelling of the salt creating a linear positive area. This positive area, in turn, caused increased deposition of sediments in adjacent areas which further enhanced salt migration. Not until late Jurassic time had flowage of the salt slowed sufficiently to allow sediments of the Morrison and younger formations to be deposited across the salt welt. A thick cap of insoluble residue was formed on top of the salt diapir as a result of salt dissolution through time. The crest of the anticline is breached; it collapsed in two stages during the Tertiary Period. The first stage was graben collapse during the early Tertiary; the second stage occurred after Miocene regional uplift had caused downcutting streams to breach the salt core resulting in further collapse. The axis of the anticline is a narrow generally flat-floored valley containing a few hills composed of downdropped Mesozoic rocks foundered, in the caprock. The caprock, which underlies thin alluvium in the valley, is composed of contorted gypsum, shale, sandstone, and limestone--the insoluble residue of the Paradox salt.

  6. Oreshoot Zoning in the Carlin-Type Betze Orebody, Goldstrike Mine, Eureka County, Nevada

    DTIC Science & Technology

    1998-01-01

    nature of oreshoots and predicting their location and shape has always been a major concern of economic geologists (Penrose, 1910; Hulin , 1929...criteria in brittle fault zones: Journal Structural Geology, v. 9, p. 609�620. G�raud, Yves, Caron, Jean- Michel , and Favre, Pierre, 1995, Porosity...Contributions to the Gold Metallogeny of Northern Nevada: U.S. Geological Survey Open-File Report 98�338, p. 202-210. Hulin , C.D., 1929, Structural

  7. Fluid inclusion and stable isotope data for the Pea Ridge Fe-REE orebody, Missouri

    SciTech Connect

    Sidder, G.B.; Day, W.C.; Rye, R.O. )

    1993-03-01

    New fluid-inclusion and stable-isotope data define the character of the mineralizing fluids that formed the iron and rare-earth-element ore deposit at the Pea Ridge Mine, southeast Missouri. These fluids were very hot and highly saline brines that may have been magmatically derived. Early, pre-magnetite ore skarn alteration of the host rhyolitic tuff took place at temperatures greater than 420 C and possibly as high as 680 C based upon calculated temperatures of quartz-magnetite pairs. Halite homogenization of three- or more phase (liquid + vapor + salts) fluid inclusions in quartz indicates that the skarn-forming fluid had a temperature of about 460 C to > 530 C and a salinity of about 45 to 57 equivalent weight percent NaCl. Analyses of [delta][sup 18]O in quartz from the skarn zone average about 14.5[per thousand], compared to a value of about 13.0[per thousand] for quartz in the host rhyolite. Average [delta][sup 34]S values for pyrite of about 2.3[per thousand] in the skarn zone may reflect a magmatic source. Magnetite ore was deposited at temperatures between about 340 C and 530 C from a fluid with a salinity between about 54 and 60 equivalent weight percent NaCl. The large apparent range of temperatures indicated by both fluid-inclusion and stable-isotope data within each zone may be due to contamination by quartz from multiple stages of quartz deposition. Also, the assumed isotopic equilibrium between some mineral pairs may be incorrect. Moreover, fluid inclusions are relatively rare in all ore and alteration zones except the silicified zone, and only a few inclusions are clearly primary in origin. Nonetheless, the predominance of high temperatures and high salinities in all of the mineralized and altered zones supports the interpretation that Pea ridge is a magmatic hydrothermal deposit. This magmatic hydrothermal model is also supported by paragenetic relations defined by geologic mapping and geochemical modeling of major-, minor-, and trace-element data.

  8. Genesis of superimposed hypogene and supergene Fe orebodies in BIF at the Madoonga deposit, Yilgarn Craton, Western Australia

    NASA Astrophysics Data System (ADS)

    Duuring, Paul; Hagemann, Steffen

    2013-03-01

    The Madoonga iron ore body hosted by banded iron formation (BIF) in the Weld Range greenstone belt of Western Australia is a blend of four genetically and compositionally distinct types of high-grade (>55 wt% Fe) iron ore that includes: (1) hypogene magnetite-talc veins, (2) hypogene specular hematite-quartz veins, (3) supergene goethite-hematite, and (4) supergene-modified, goethite-hematite-rich detrital ores. The spatial coincidence of these different ore types is a major factor controlling the overall size of the Madoonga ore body, but results in a compositionally heterogeneous ore deposit. Hypogene magnetite-talc veins that are up to 3 m thick and 50 m long formed within mylonite and shear zones located along the limbs of isoclinal, recumbent F1 folds. Relative to least-altered BIF, the magnetite-talc veins are enriched in Fe2O3(total), P2O5, MgO, Sc, Ga, Al2O3, Cl, and Zr; and depleted in SiO2 and MnO2. Mafic igneous countryrocks located within 10 m of the northern contact of the mineralised BIF display the replacement of primary igneous amphibole and plagioclase, and metamorphic chlorite by hypogene ferroan chlorite, talc, and magnetite. Later-forming, hypogene specular hematite-quartz veins and their associated alteration halos partly replace magnetite-talc veins in BIF and formed during, to shortly after, the F2-folding and tilting of the Weld Range tectono-stratigraphy. Supergene goethite-hematite ore zones that are up to 150 m wide, 400 m long, and extend to depths of 300 m replace least-altered BIF and existing hypogene alteration zones. The supergene ore zones formed as a result of the circulation of surface oxidised fluids through late NNW- to NNE-trending, subvertical brittle faults. Flat-lying, supergene goethite-hematite-altered, detrital sediments are concentrated in a paleo-topographic depression along the southern side of the main ENE-trending ridge at Madoonga. Iron ore deposits of the Weld Range greenstone belt record remarkably similar deformation histories, overprinting hypogene alteration events, and high-grade Fe ore types to other Fe ore deposits in the wider Yilgarn Craton (e.g. Koolyanobbing and Windarling deposits) despite these Fe camps being presently located more than 400 km apart and in different tectono-stratigraphic domains. Rather than the existence of a synchronous, Yilgarn-wide, Fe mineralisation event affecting BIF throughout the Yilgarn, it is more likely that these geographically isolated Fe ore districts experienced similar tectonic histories, whereby hypogene fluids were sourced from commonly available fluid reservoirs (e.g. metamorphic, magmatic, or both) and channelled along evolving structures during progressive deformation, resulting in several generations of Fe ore.

  9. Assessment of Sediment Risk in the North End of Tai Lake, China: Integrating Chemical Analysis and Chronic Toxicity Testing with Chironomus dilutus.

    PubMed

    Qi, Hongxue; Ma, Ping; Li, Huizhen; You, Jing

    2015-11-01

    Whole life-cycle bioassays with Chironomus dilutus were performed to evaluate sediment toxicity in Tai Lake, a typical freshwater lake in China. Meanwhile, contaminants of concern were analyzed in sediment. The sediments in Tai Lake showed no acute mortality in 10-day testing to C. dilutus. After chronic exposure to the sediments, however, adverse effects-including decreased survival and sublethal impairments of growth, emergence, and fecundity-were observed at most sites in Tai Lake. A variety of contaminants were detected in sediment with the total concentrations in the range of 504-889 ng/g dry weight (dw) for polycyclic aromatic hydrocarbons, 0.56-1.81 ng/g dw for polychlorinated biphenyls, 38.6-87.8 ng/g dw for polybrominated diphenyl ethers, 8.34-14.2 ng/g dw for organochlorine pesticides, 1.27-2.95 ng/g dw for organophosphate pesticides, 0.11-0.21 ng/g dw for pyrethroid pesticides, and 332-609 µg/g dw for metals. Finally, a canonical correlation analysis was applied to link chronic sediment toxicity to the toxic units of individual contaminants. Results suggested that two pesticides (hexachlorocyclohexane and chlorpyrifos) and two metals (chromium and nickel) in sediments from Tai Lake were the potential contributors to the noted toxicity in C. dilutus in the life-cycle toxicity testing. In conclusion, acute bioassays with the benthos were not sensitive enough to assess sediment toxicity in freshwater lakes in China, and it is desirable to integrate chronic toxicity testing with chemical analysis to better understand sediment risk.

  10. Environmental Assessment Addressing FTFA07-1174, Repair Approach Lighting System at the North End of Runway 01/19 at Eglin AFB, Florida

    DTIC Science & Technology

    2013-05-01

    photovoltaic panels, solar collection, heat recovery systems, wind turbines , green roofs, and habitat-oriented storm water management) would be...and im pacts on the installation ’s habitats will be reduced with the im plementation of BMPs and environmental protection measures. Most wildlife wi...disturbing activities occurring at the same time and in lhe same vicinity could have temporary cumulative effects on habitats and wildlife . However. these

  11. A reinterpretation of the δDH2O of inclusion fluids in contemporaneous quartz and sphalerite, Creede mining district, Colorodo: a generic problem for shallow orebodies?

    USGS Publications Warehouse

    Foley, Nora K.; Bethke, Philip M.; Rye, Robert O.

    1989-01-01

    The unusually high contrast between the salinities of the ore-depositing fluids and the ground water overlying the ore zone allowed recognition of this phenomenon at Creede. It is likely, however, that Creede is not unique. Similar phenomena may be common in shallow ore zones where rapid fluctuation of an interface between a deep, high-temperature thermal plume and an overlying, cooler ground water may be expected to occur. Careful study of the origins of fluid inclusions, particularly in quartz, is essential to characterize the primary ore fluids and to assess the role of ground water in the hydrology of shallow ore deposits.

  12. Magmatic Conduit Metallogenic System in Jinchuan Cu-Ni (PGE) Sulfide Deposit

    NASA Astrophysics Data System (ADS)

    Su, S.; Tang, Z.; Zhou, M.; Song, C.

    2014-12-01

    The Jinchuan Cu-Ni (PGE) sulfide deposit is located in the southwestern margin of North China Craton. Jinchuan ultramafic intrusion hosts the third largest magmatic Cu-Ni deposit in the world. There are mainly four orebodies, namely, orebody-58, orebody-24, orebody-1, and orebody-2, respectively from west to east in the deposit. The primary characteristics of Jinchuan Cu-Ni sulfide deposit are the following: (1) There is an obvious boundary between orebodys and country rocks, usually orebodys intruded into country rocks. (2) "sulfide melts" migrate and settle in the later stage of magma evolution. (3) Fluid Minerals Assemblages are found in the sulfide ores, there is Phl+Cc+Pn+Ccp+Po in orebody-2; Phl+Dol+AP+Pn+Ccp+Po in orebody-24; Q+Mag+AP+Pn+Ccp+Po in orebody-58. (4) Massive sulfides mainly occur in orebody-2, and its PGE content is very rare. Pt-Pd enrichment zones mainly occur in orebody-1; orebody-24 and orebody-58. Ir vs. Ru, Rh, Pt, Pd show positive relationship in orebody-2, but Ir vs. Ru, Rh show positive relationship, Ir vs. Pt, Pd exhibit negative relationship in orebody-1, orebody-24 and orebody-58. The modeling of Ir-Pd shows that the massive sulfide in orebody-2 maybe the origin of MSS. Pt-Pd enrichment zones in orebody-1 orebody-24 and orebody-58 are the relic liquid of monosulfide solid solution segregation; (5) Cu/Ni value is 1.24 in orebody-58, 1.56 in orebody-24, 1.83 in orebody-1, and 2.06 in orebody-2. These features imply that (1) "ore magma" or "melt-fluid bearing metal" formed in the staging chamber in depth; (2) "ore magma" might contain a lot of fluids; (3) "melt-fluid bearing metal" flow moves as a whole; (4) The moving direction of melt-fluid bearing metal flow is form west to east. The ores are enriched in Ni in the front, and enriched in Cu, Pt, Pd in the back of Jinchuan Magmatic Conduit Metallogenic System.

  13. Quantifying multi-element and volumetric uncertainty, Coleman McCreedy deposit, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Goodfellow, Ryan; Albor Consuegra, Francisco; Dimitrakopoulos, Roussos; Lloyd, Tim

    2012-05-01

    Traditional geostatistical modelling of orebodies and estimation of grade-tonnage curves do not account for the uncertainty of the orebody grades and tonnages. Geological interpretations of complex shapes are often over-constrained, and therefore do not properly identify the location of the ore. In these situations, tonnage is often under-estimated and grade is over-estimated, resulting in orebody models used for mine planning that lead to costly financial decisions. This paper presents an approach aiming to better assess the uncertainty in an orebody model. The approach is applied to Vale's West Orebody of the Coleman McCreedy Mine, a poly-metallic deposit containing nickel, copper, gold, platinum and palladium. To encapsulate the orebody's variability and uncertainty, the nickel-copper sulphide mineralized zone is simulated using the single normal equation simulation method. The realizations serve as the orebody models from which the grades of multiple elements are jointly simulated using Min/Max Autocorrelation Factors. The final result is a series of equiprobable representations of the mineralization that incorporates both grade and tonnage uncertainty. The case study indicates that had conventional orebody estimations been used, there would have been a 10% over-estimation of orebody volume, along with significant over-estimation of low-grade material and under-estimation of high-grade material.

  14. 14. VIEW TO WESTSOUTHWEST ACROSS CAR TEST TRACT SITE TO ...

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

    14. VIEW TO WEST-SOUTHWEST ACROSS CAR TEST TRACT SITE TO NORTH END OF ASSEMBLY PLANT, SHOWING NORTH END ADDITIONS. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  15. Use of structural geology in exploration for and mining of sedimentary rock-hosted Au deposits

    USGS Publications Warehouse

    Peters, Stephen G.

    2001-01-01

    Structural geology is an important component in regional-, district- and orebody-scale exploration and development of sedimentary rock-hosted Au deposits.Identification of timing of important structural events in an ore district allows analysis and classification of fluid conduits and construction of genetic models for ore formation.The most practical uses of structural geology deal with measurement and definition of various elements that comprise orebodies, which can then be directly applied to ore-reserve estimation,ground control,grade control, safety issues,and mine planning.District- and regional-scale structural studies are directly applicable to long-term strategic planning,economic analysis,and land ownership. Orebodies in sedimentary rock-hosted Au deposits are discrete, hypogene, epigenetic masses usually hosted in a fault zone,breccia mass, or lithologic bed or unit. These attributes allow structural geology to be directly applied to the mining and exploration of sedimentary rock-hosted Au deposits. Internal constituents in orebodies reflect unique episodes relating to ore formation.The main internal constituents in orebodies are ore minerals, gangue, and alteration minerals that usually are mixed with one another in complex patterns, the relations among which may be used to interpret the processes of orebody formation and control.Controls of orebody location and shape usually are due to structural dilatant zones caused by changes in attitude, splays, lithologic contacts,and intersections of the host conduit or unit.In addition,conceptual parameters such as district fabric,predictable distances, and stacking also are used to understand the geometry of orebodies.Controls in ore districts and location and geometry of orebodies in ore districts can be predicted to various degrees by using a number of qualitative concepts such as internal and external orebody plunges,district plunge, district stacking, conduit classification, geochemical, geobarometric and

  16. 81. PHOTOCOPY OF DRAWING, SURFACE BUILDINGS, GENERAL, TRANSFORMER HOUSE, LOWER ...

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

    81. PHOTOCOPY OF DRAWING, SURFACE BUILDINGS, GENERAL, TRANSFORMER HOUSE, LOWER CAMP, NORTH END - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  17. 82. PHOTOCOPY OF DRAWING, SURFACE BUILDINGS, GENERAL, TRANSFORMER HOUSE, LOWER ...

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

    82. PHOTOCOPY OF DRAWING, SURFACE BUILDINGS, GENERAL, TRANSFORMER HOUSE, LOWER CAMP, NORTH END - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  18. 24. Aerial photograph dated 22 April 1942, showing Gould Island ...

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

    24. Aerial photograph dated 22 April 1942, showing Gould Island from the northeast. Complex under construction includes shop building (large rectangle at north end of island, and firing pier (at far right). Photo courtesy of Naval Undersea Warfare Center, Division Newport, Rhode Island. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  19. 7. CABLE RACK, MEZZANINE LEVEL, INTERIOR OF TEST STAND 1A. ...

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

    7. CABLE RACK, MEZZANINE LEVEL, INTERIOR OF TEST STAND 1A. Looking north from north end of the cable tunnel leading toward Control Center. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  20. 17. HOLDING TANKS AND SLUICE DOORS This picture is taken ...

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

    17. HOLDING TANKS AND SLUICE DOORS This picture is taken from atop the redwood holding tanks at the north end of the building, looking across at the north end of the building. Below can be seen the sluice doors through which the fish flowed to the cutting area. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  1. Fast 3D Focusing Inversion of Gravity Data Using Reweighted Regularized Lanczos Bidiagonalization Method

    NASA Astrophysics Data System (ADS)

    Rezaie, Mohammad; Moradzadeh, Ali; Kalate, Ali Nejati; Aghajani, Hamid

    2017-01-01

    Inversion of gravity data is one of the important steps in the interpretation of practical data. One of the most interesting geological frameworks for gravity data inversion is the detection of sharp boundaries between orebody and host rocks. The focusing inversion is able to reconstruct a sharp image of the geological target. This technique can be efficiently applied for the quantitative interpretation of gravity data. In this study, a new reweighted regularized method for the 3D focusing inversion technique based on Lanczos bidiagonalization method is developed. The inversion results of synthetic data show that the new method is faster than common reweighted regularized conjugate gradient method to produce an acceptable solution for focusing inverse problem. The new developed inversion scheme is also applied for inversion of the gravity data collected over the San Nicolas Cu-Zn orebody in Zacatecas State, Mexico. The inversion results indicate a remarkable correlation with the true structure of the orebody that is achieved from drilling data.

  2. Origin of the Nchanga copper-cobalt deposits of the Zambian Copperbelt

    NASA Astrophysics Data System (ADS)

    McGowan, Ross R.; Roberts, Stephen; Boyce, Adrian J.

    2006-01-01

    The Zambian Copperbelt forms the southeastern part of the 900-km-long Neoproterozoic Lufilian Arc and contains one of the world’s largest accumulations of sediment-hosted stratiform copper mineralization. The Nchanga deposit is one of the most significant ore systems in the Zambian Copperbelt and contains two major economic concentrations of copper and cobalt, hosted within the Lower Roan Group of the Katangan Supergroup. A Lower Orebody (copper only) and Upper Orebody (copper and cobalt) occur towards the top of arkosic units and within the base of overlying shales. The sulfide mineralogy includes pyrite, bornite, chalcopyrite, and chalcocite, although in the Lower Orebody, sulfide phases are partially or completely replaced by malachite and copper oxides. Carrollite is the major cobalt-bearing phase and is restricted to fault-propagation fold zones within a feldspathic arenite. Hydrothermal alteration minerals include dolomite, phlogophite, sericite, rutile, quartz, tourmaline, and chlorite. Quartz veins from the mine sequence show halite-saturated fluid inclusions, ranging from ~31 to 38 wt% equivalent NaCl, with homogenisation temperatures (ThTOT) ranging between 140 and 180°C. Diagenetic pyrites in the lower orebody show distinct, relatively low δ 34S, ranging from -1 to -17‰ whereas arenite- and shale-hosted copper and cobalt sulfides reveal distinctly different δ 34S from -1 to +12‰ for the Lower Orebody and +5 to +18‰ for the Upper Orebody. There is also a clear distinction between the δ 34S mean of +12.1±3.3‰ ( n=65) for the Upper Orebody compared with +5.2±3.6‰ ( n=23) for the Lower Orebody. The δ 13C of dolomites from units above the Upper Orebody give δ 13C values of +1.4 to +2.5‰ consistent with marine carbon. However, dolomite from the shear-zones and the alteration assemblages within the Upper Orebody show more negative δ 13C values: -2.9 to -4.0‰ and -5.6 to -8.3‰, respectively. Similarly, shear zone and Upper Orebody

  3. Historical lead isotope record of a sediment core from the Derwent River (Tasmania, Australia): a multiple source environment.

    PubMed

    Townsend, Ashley T; Seen, Andrew J

    2012-05-01

    A 105 cm sediment core from the Derwent River (Tasmania, Australia) was collected in 2004 and was characterised considering both physical (loss on ignition at 550 °C and grain size) and chemical (Fe, Cu, Zn, Cd and Pb concentrations, Pb isotope ratios and (210)Pb dating) properties. The core was analysed to (i) investigate the historical profiles of some important elements associated with the Risdon zinc refinery adjacent to the Derwent River, (ii) determine Pb isotopic signatures of sediment samples, and (iii) assess the veracity of Pb isotope ratios as indicators of contaminant Pb input. Extractable metal concentrations were (all values as mgkg(-1), non-normalised for grain size) Fe: 20,000-35,000, Zn: 42-4500, Pb: 5-1090, Cu: 13-141, and Cd: 1-31; with a close correlation between Cu, Zn, Cd and Pb. Metal enrichment factors (normalised to Al) were Pb: 0.9-144, Zn: 0.8-93, Cd: 0.8-30, Cu: 0.8-8.9 and Fe: 0.9-1.3, confirming anthropogenic contributions of Cu, Zn, Pb and Cd to the sediments. The onset of metal contamination above background levels occurred at a depth between 43 and 49 cm, with maximum concentrations noted near 20 cm for Cu, Zn, Cd and Pb. Lead isotope ratios were determined in sediments using sector field ICP-MS, and were found to be 36.5-38.8, 16.5-18.7 and 1.07-1.20 for (208)Pb/(204)Pb, (206)Pb/(204)Pb and (206)Pb/(207)Pb ratios, respectively. Major Australian ores processed at the refinery over the previous ~90 years include those from Broken Hill, Rosebery, Mt Isa, Elura, Hellyer and Century deposits. Anthropogenic impact by Pb with Broken Hill type isotopic ratio was initially evident in the core at 43-49 cm. The introduction of Rosebery and Elura ores to the refinery was also clearly noted. Pb isotope ratios further highlight that the Derwent River has been exposed to a greater impact by anthropogenic Pb in comparison to other major Tasmanian rivers, namely the Huon and Tamar.

  4. 18. VIEW NORTHEAST, SHAFT, CAM, AND OPERATING ARM FOR NORTH ...

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

    18. VIEW NORTHEAST, SHAFT, CAM, AND OPERATING ARM FOR NORTH END LOCK, INBOARD SIDE OF WEST BASCULE GIRDER - Grand Street Bridge, Spanning Pequonnock River at Grand Street, Bridgeport, Fairfield County, CT

  5. 7. FIRST FLOOR, INTERIOR, DETAIL OF FISH SMOKING OVEN LOCATED ...

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

    7. FIRST FLOOR, INTERIOR, DETAIL OF FISH SMOKING OVEN LOCATED IN NORTH END OF BUILDING, ALONG WEST WALL; LOOKING WEST - Gerber Sheet Metal Works Building, 128 Porthand Avenue, South, Minneapolis, Hennepin County, MN

  6. 13. Historic American Buildings Survey Alex Bush, Photographer, January 8, ...

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

    13. Historic American Buildings Survey Alex Bush, Photographer, January 8, 1937 STAIR ON NORTH END OF PORTICO - Wilcox County Courthouse, Broad, Claiborne, Court & Water Streets, Camden, Wilcox County, AL

  7. 17. Interior first level view looking north within forward (north) ...

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

    17. Interior first level view looking north within forward (north) section of firing pier. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  8. 18. Interior first level view looking northnortheast within forward (north) ...

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

    18. Interior first level view looking north-northeast within forward (north) section of firing pier, with office module toward foreground. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  9. 11. Submersible torpedo tube mounted on platform of elevator at ...

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

    11. Submersible torpedo tube mounted on platform of elevator at northeast (starboard) elevator tower. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  10. 3. VIEW OF EAST SOUTHEAST, GROUND LEVEL VIEW OF ...

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

    3. VIEW OF EAST - SOUTHEAST, GROUND LEVEL VIEW OF APPROACH SPANS, NORTH END OF BRIDGE, MAIN SPANS IN BACKGROUND - Buffalo River Bridge, Spanning Buffalo River on U.S. Highway 65, Marshall, Searcy County, AR

  11. 4. Historic American Buildings Survey, Frederik C. Gjessing, Photographer April ...

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

    4. Historic American Buildings Survey, Frederik C. Gjessing, Photographer April 19, 1954 WALL FRAGMENT AT NORTH END OF SECOND LINE OF DEFENSE, EAST ELEVATION. - Fortifications of San Juan, Outer Defenses, Puerta de Tierra, San Juan, San Juan Municipio, PR

  12. 3. Historic American Buildings Survey, Frederik C. Gjessing, Photographer April ...

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

    3. Historic American Buildings Survey, Frederik C. Gjessing, Photographer April 19, 1954 WALL FRAGMENTS AT NORTH END OF SECOND LINE OF DEFENSE, NORTH ELEVATION. - Fortifications of San Juan, Outer Defenses, Puerta de Tierra, San Juan, San Juan Municipio, PR

  13. 10. VIEW OF BUILDING 6. INTERIOR OF SINGLE STORY SECTION ...

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

    10. VIEW OF BUILDING 6. INTERIOR OF SINGLE STORY SECTION AT NORTH END. FACING SOUTHEAST. - Winehaven, Storage Cellar & Fermentation Room, Point Molate Naval Fuel Depot, Richmond, Contra Costa County, CA

  14. 7. MOTION PICTURE CAMERA STAND AT BUILDING 8768. Edwards ...

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

    7. MOTION PICTURE CAMERA STAND AT BUILDING 8768. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  15. 1. GENERAL PERSPECTIVE VIEW OF TOWN OF ATLANTIC CITY, LOOKING ...

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

    1. GENERAL PERSPECTIVE VIEW OF TOWN OF ATLANTIC CITY, LOOKING NORTH FROM NINTH FLOOR OF CEASAR'S PARKING GARAGE ON KENTUCKY AVENUE - Town of Atlantic City, North end of Absecon Island, South of Absecon Channel, Atlantic City, Atlantic County, NJ

  16. 14. Historic American Buildings Survey, John O. Brostrup, Photographer January ...

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

    14. Historic American Buildings Survey, John O. Brostrup, Photographer January 13, 1937 1:45 P.M. COPY OF TEXT, NORTH END OF EAST WALL IN CHAPEL OF SAAL. - The Cloisters, Saal, Ephrata, Lancaster County, PA

  17. 10. Historic American Buildings Survey, John O. Brostrup, Photographer January ...

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

    10. Historic American Buildings Survey, John O. Brostrup, Photographer January 13, 1937 11:35 A.M. COPY OF TEXT, NORTH END OF WEST WALL IN CHAPEL OF SAAL. - The Cloisters, Saal, Ephrata, Lancaster County, PA

  18. 4. VIEW OF WATER TOWER FROM ELECTRICAL TRANSFORMER CAGE AT ...

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

    4. VIEW OF WATER TOWER FROM ELECTRICAL TRANSFORMER CAGE AT NORTH END OF SECOND FLOOR WAREHOUSE. VIEW TO WEST-NORTHWEST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  19. Interior detail of exit door on second floor at north ...

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

    Interior detail of exit door on second floor at north end; camera facing north. - Mare Island Naval Shipyard, WAVES Officers Quarters, Cedar Avenue, west side between Tisdale Avenue & Eighth Street, Vallejo, Solano County, CA

  20. VIEW OF THE FRONT SIDE OF BOAT LANDING S370 NEAR ...

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

    VIEW OF THE FRONT SIDE OF BOAT LANDING S370 NEAR NORTH END, FACING WEST - U.S. Naval Base, Pearl Harbor, Boat Landing S370, Along Essex Street at Southeast shore of Ford Island, Pearl City, Honolulu County, HI

  1. 22. DETAIL, TWO LIGHTING TYPES AT REAR OF TEST STAND ...

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

    22. DETAIL, TWO LIGHTING TYPES AT REAR OF TEST STAND 1-A. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  2. 4. Upper level of marine museum looking southwest at enclosed ...

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

    4. Upper level of marine museum looking southwest at enclosed exterior wall of area office building - Duluth Ship Canal, Marine Museum-Area Office, North end of Minnesota Point at Canal Park, Duluth, St. Louis County, MN

  3. 7. North side of marine museum and area office building ...

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

    7. North side of marine museum and area office building looking south-southwest - Duluth Ship Canal, Marine Museum-Area Office, North end of Minnesota Point at Canal Park, Duluth, St. Louis County, MN

  4. 3. Eastlooking view of marine museum lower and upper floors ...

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

    3. East-looking view of marine museum lower and upper floors from area office building window - Duluth Ship Canal, Marine Museum-Area Office, North end of Minnesota Point at Canal Park, Duluth, St. Louis County, MN

  5. 8. Historic American Buildings Survey PHOTOCOPY CA. 1916 OF SLEEPING ...

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

    8. Historic American Buildings Survey PHOTOCOPY CA. 1916 OF SLEEPING PORCH, AT NORTH END CAPABLE OF SLEEPING SIX. Original in Collections of Marian College - James A. Allison Mansion, 3200 Coldspring Road, Indianapolis, Marion County, IN

  6. 12. View to north along recovery dock along east side ...

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

    12. View to north along recovery dock along east side of firing pier. Steel brackets originally supported a sheltering canopy over the dock. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  7. 1. PAINT AND OIL STORAGE SHED, FRONT, LOOKING SOUTHWEST. ...

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

    1. PAINT AND OIL STORAGE SHED, FRONT, LOOKING SOUTHWEST. - NIKE Missile Base SL-40, Paint & Oil Storage Shed, North end of base, northwest of Mess Hall & south of Basketball Court, Hecker, Monroe County, IL

  8. 2. PAINT AND OIL STORAGE SHED, FRONT AND RIGHT SIDES, ...

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

    2. PAINT AND OIL STORAGE SHED, FRONT AND RIGHT SIDES, LOOKING SOUTH. - NIKE Missile Base SL-40, Paint & Oil Storage Shed, North end of base, northwest of Mess Hall & south of Basketball Court, Hecker, Monroe County, IL

  9. 3. VIEW, LOOKING EAST, SHOWING OPEN SPACE AT RANGE BUILDING ...

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

    3. VIEW, LOOKING EAST, SHOWING OPEN SPACE AT RANGE BUILDING AT NORTH END, Interior - Winchester Repeating Arms Company, Tract K Shooting Range, 125 Munson Street (rear section), New Haven, New Haven County, CT

  10. 3. VIEW, LOOKING SOUTHEAST, SHOWING WEST LONGITUDINAL ELEVATION OF NORTH ...

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

    3. VIEW, LOOKING SOUTHEAST, SHOWING WEST LONGITUDINAL ELEVATION OF NORTH END SPAN - East Bloomsburg Bridge, Spanning Susquehanna River at Pennsylvania Route 487 (Legislative Route 283), Bloomsburg, Columbia County, PA

  11. VIEW OF THE BOILER ROOM WITH STACK TO THE LEFT ...

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

    VIEW OF THE BOILER ROOM WITH STACK TO THE LEFT AND NORTH END OF THE BAGASSE STORE HOUSE TO THE RIGHT. VIEW FROM THE WEST - Kekaha Sugar Company, Sugar Mill Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

  12. 4. BUILDING 8767, INTERIOR. Looking west. Edwards Air Force ...

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

    4. BUILDING 8767, INTERIOR. Looking west. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  13. 6. BUILDING 8768, NORTHWEST SIDE AND SOUTHWEST FRONT. Edwards ...

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

    6. BUILDING 8768, NORTHWEST SIDE AND SOUTHWEST FRONT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  14. 8. BUILDING 8769, WEST FRONT AND SOUTH SIDE. Edwards ...

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

    8. BUILDING 8769, WEST FRONT AND SOUTH SIDE. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  15. 2. BUILDING 8767, SOUTH FRONT AND EAST SIDE. Edwards ...

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

    2. BUILDING 8767, SOUTH FRONT AND EAST SIDE. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  16. 14. VIEW OF AREA TO BE INUNDATED FOR EASTSIDE RESERVOIR, ...

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

    14. VIEW OF AREA TO BE INUNDATED FOR EASTSIDE RESERVOIR, LOOKING SOUTHEAST FROM OBSERVATORY HILL AT NORTH END OF WEST DAM. - Eastside Reservoir, Diamond & Domenigoni Valleys, southwest of Hemet, Hemet, Riverside County, CA

  17. 22. DETAIL EXTERIOR VIEW LOOKING NORTHWEST, SHOWING FISH LADDER AT ...

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

    22. DETAIL EXTERIOR VIEW LOOKING NORTHWEST, SHOWING FISH LADDER AT NORTH END OF DAM/SPILLWAY; VIEW SHOWS SECTION OF FISH LADDER NEAR WHERE IT ENTERS THE COLUMBIA RIVER. - Bonneville Project, Bonneville Dam, Columbia River, Bonneville, Multnomah County, OR

  18. 24. DETAIL EXTERIOR VIEW LOOKING EAST, SHOWING FISH LADDER AT ...

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

    24. DETAIL EXTERIOR VIEW LOOKING EAST, SHOWING FISH LADDER AT NORTH END OF DAM/SPILLWAY; WATER FLOWING THROUGH FISH LADDER IS VISIBLE AT BOTTOM. - Bonneville Project, Bonneville Dam, Columbia River, Bonneville, Multnomah County, OR

  19. Facility No. 171, oblique view of west side and north ...

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

    Facility No. 171, oblique view of west side and north end, with Facility Nos. 170 and S169 in the background - U.S. Naval Base, Pearl Harbor, Inert Ammunition Storehouses, Avocet and Kingfisher Streets, Pearl City, Honolulu County, HI

  20. 44. 'Submarine Torpedo Tube Foundation and Towers,' Y&D Drawing 226855, ...

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

    44. 'Submarine Torpedo Tube Foundation and Towers,' Y&D Drawing 226855, approved by Bureau of Ordnance. Dated 20 October 1943. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  1. 14. DETAIL SHOWING HYDROGEN (LEFT) AND OXYGEN (RIGHT) PREVALVES. Looking ...

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

    14. DETAIL SHOWING HYDROGEN (LEFT) AND OXYGEN (RIGHT) PREVALVES. Looking southeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  2. 16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEENINCH BALL VALVE. Looking ...

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

    16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEEN-INCH BALL VALVE. Looking southwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  3. 17. DETAIL, FOURTEENINCH LIQUID OXYGEN BALL VALVE. Looking south southeast. ...

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

    17. DETAIL, FOURTEEN-INCH LIQUID OXYGEN BALL VALVE. Looking south southeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  4. 25. Detail of cast iron lamp post base with fluted ...

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

    25. Detail of cast iron lamp post base with fluted wooded post at top, located at north end of bridge. VIEW NORTHEAST - Chelsea Street Bridge & Draw Tender's House, Spanning Chelsea River, Boston, Suffolk County, MA

  5. 5. EAST SIDE, TEST STAND AND ITS SUPERSTRUCTURE. Edwards ...

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

    5. EAST SIDE, TEST STAND AND ITS SUPERSTRUCTURE. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  6. 4. DETAIL SHOWING FLAME DEFLECTOR. Looking southeast. Edwards Air ...

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

    4. DETAIL SHOWING FLAME DEFLECTOR. Looking southeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  7. 8. SOUTH REAR, SUPERSTRUCTURE. Looking north from deck. Edwards ...

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

    8. SOUTH REAR, SUPERSTRUCTURE. Looking north from deck. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  8. DETAIL, CONTROL BOOTH, RP1 TANK FARM Edwards Air Force ...

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

    DETAIL, CONTROL BOOTH, RP1 TANK FARM - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Combined Fuel Storage Tank Farm, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  9. 11. DETAIL SHOWING ROLLING ENGINE DECK AND NORTHEAST TRUSS OF ...

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

    11. DETAIL SHOWING ROLLING ENGINE DECK AND NORTHEAST TRUSS OF SUPERSTRUCTURE. Looking northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  10. DELUGE AND WATER RECLAMATION BASIN BELOW TEST STAND 1A. Looking ...

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

    DELUGE AND WATER RECLAMATION BASIN BELOW TEST STAND 1-A. Looking north northwest - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Flame Deflector Water System, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  11. 30. Bronze plaque located on southern inner wall at east ...

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

    30. Bronze plaque located on southern inner wall at east end of south pier taken looking southeast - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  12. 3. Historic American Buildings Survey Lanny Miyamoto, Photographer October 1958 ...

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

    3. Historic American Buildings Survey Lanny Miyamoto, Photographer October 1958 INTERIOR, BREAKFAST ROOM, NORTH END - Garrett-Jacobs House, 7, 9, 11, 13 West Mount Vernon Place, Baltimore, Independent City, MD

  13. The Balmat-Edwards zinc-lead deposits-synsedimentary ore from Mississippi valley-type fluids.

    USGS Publications Warehouse

    Whelan, J.F.; Rye, R.O.; Delorraine, W.

    1984-01-01

    The Balmat-Edwards Zn-Pb district in New York is in Mid-Proterozoic Grenville marbles. Tabular to podiform, generally conformable massive sphalerite-galena orebodies occur at various horizons in the approx 1 km-thick marbles. Metamorphism obscured or obliterated most primary characteristics, whose reconstruction is attempted through detailed S, C, and O isotope studies of the Fowler orebody, and trace element and S isotope studies of sphalerite concentrates and composite ore samples from 22 orebodies. Sulphur isotope data reflect equilibration at near peak metamorphism with some indication of re-equilibration during retrograde metamorphism. The carbon and oxygen isotope composition of gangue carbonates suggests derivation from the host marbles. The oxygen isotope composition of gangue quartz is compatible with a chert origin or metamorphism-equilibration with other minerals. Sulphur and lead isotopes and sulphide mineralogy suggests that the ore fluids were evolved basin brines, chemically like those responsible for Mississippi Valley-type deposits. The large stratigraphic span (> 600 m) of the Balmat orebodies may be due to basin dewatering of million-year intervals. Stratigraphically increasing 34S values of evaporite-anhydrite are postulated to record hydrothermal events and to imply bacterial sulphate reduction on an unusually large scale. Such a stratigraphic increase may be a general exploration guide where sediment-hosted exhalative deposits or Mississippi Valley-type deposits occur.-G.J.N.

  14. Gravity measurements useful in the preliminary evaluation of the Nimiuktuk barite deposit, Alaska.

    USGS Publications Warehouse

    Barnes, D.F.; Mayfield, C.F.; Morin, R.L.; Brynn, S.

    1982-01-01

    Measurements taken in 1979 are used to assess the Nimiuktuk deposit; combined models suggest that the orebody contains a total mass of >1.5M metric tons of high-grade barite. The anomaly associated with Nimiuktuk suggests that gravity exploration could locate other massive deposits.-after Authors

  15. 27. Aerial photograph dated 14 October 1943 taken directly over ...

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

    27. Aerial photograph dated 14 October 1943 taken directly over Gould Island. Completed complex shown at north end of the island (to right in photograph), including power plant, shop, frame approach, firing pier, and small harbor formed by finger pier off east side of firing pier. Photo courtesy of Naval Undersea Warfare Center, Division Newport, Rhode Island. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  16. Preliminary mineralogic, fluid inclusion, and stable isotope study of the Mahd adh Dhahab gold mine, Kingdom of Saudi Arabia

    USGS Publications Warehouse

    Rye, Robert O.; Hall, W.E.; Cunningham, C.G.; Czamanske, G.K.; Afifi, A.M.; Stacey, J.S.

    1983-01-01

    The Mahd adh Dhahab mine, located about 280 km northeast of Jiddah, Kingdom of Saudi Arabia, has yielded more than 2 million ounces of gold from periodic production during the past 3,000 years. A new orebody on the southern side of the ancient workings, known as the South orebody, is being developed by Gold Fields-Mahd adh Dhahab Limited. A suite of samples was collected from the newly exposed orebody for preliminary mineralogic, stable isotope, fluid inclusion, and geochemical studies. The Mahd adh Dhahab deposit is in the carapace of a Proterozoic epizonal rhyolite stock that domed pyroclastic and metasedimentary rocks of the Proterozoic Halaban group. Ore of gold, silver, copper, zinc, tellurium, and lead is associated with north-trending, steeply dipping quartz veins in a zone 1,000 m long and 400 m wide. The veins include an assemblage of quartz-chlorite-pyrite-hematite-chalcopyrite-sphalerite-precious metals, which is similar to the mineral assemblage at the epithermal deposit at Creede, Colorado. The primary ore contains abundant chalcopyrite, sphalerite, and pyrite in addition to a complex precious metal assemblage. Gold and silver occur principally as minute grains of telluride minerals disseminated in quartz-chlorite-hematite and as inclusions in chalcopyrite and sphalerite. Telluride minerals include petzite, hessite, and sylvanite. Free gold is present but not abundant. All of the vein-quartz samples contained abundant, minute inclusions of both low-density, vapor-rich fluids and liquid-rich fluids. Primary fluid inclusions yielded homogenization temperatures of from 110? to 238? C. Preliminary light-stable isotope studies of the sulfide minerals and quartz showed that all of the d34S values are between 1.2 and 6.3 per mil, which is a typical range for hydrothermal sulfide minerals that derive their sulfur from an igneous source. The data-suggest that the sulfide sulfur isotope geochemistry was controlled by exchange with la large sulfur isotope

  17. Spatial and temporal zoning of hydrothermal alteration and mineralization in the Sossego iron oxide-copper-gold deposit, Carajás Mineral Province, Brazil: Paragenesis and stable isotope constraints

    USGS Publications Warehouse

    Monteiro, Lena V.S.; Xavier, R.P.; Carvalho, E.R.; Hitzman, M.W.; Johnson, C.A.; Souza, Filho C.R.; Torresi, I.

    2008-01-01

    The Sossego iron oxide–copper–gold deposit (245 Mt @ 1.1% Cu, 0.28 g/t Au) in the Carajás Mineral Province of Brazil consists of two major groups of orebodies (Pista–Sequeirinho–Baiano and Sossego–Curral) with distinct alteration assemblages that are separated from each other by a major high angle fault. The deposit is located along a regional WNW–ESE-striking shear zone that defines the contact between metavolcano–sedimentary units of the ∼2.76 Ga Itacaiúnas Supergroup and tonalitic to trondhjemitic gneisses and migmatites of the ∼2.8 Ga Xingu Complex. The deposit is hosted by granite, granophyric granite, gabbro, and felsic metavolcanic rocks. The Pista–Sequeirinho–Baiano orebodies have undergone regional sodic (albite–hematite) alteration and later sodic–calcic (actinolite-rich) alteration associated with the formation of massive magnetite–(apatite) bodies. Both these alteration assemblages display ductile to ductile–brittle fabrics. They are cut by spatially restricted zones of potassic (biotite and potassium feldspar) alteration that grades outward to chlorite-rich assemblages. The Sossego–Curral orebodies contain weakly developed early albitic alteration and very poorly developed subsequent calcic–sodic alteration. These orebodies contain well-developed potassic alteration assemblages that were formed during brittle deformation that resulted in the formation of breccia bodies. Breccia matrix commonly displays coarse mineral infill suggestive of growth into open space. Sulfides in both groups of deposits were precipitated first with potassic alteration and more importantly with a later assemblage of calcite–quartz–epidote–chlorite. In the Sequeirinho orebodies, sulfides range from undeformed to deformed; sulfides in the Sossego–Curral orebodies are undeformed. Very late, weakly mineralized hydrolytic alteration is present in the Sossego/Currral orebodies. The sulfide assemblage is dominated by chalcopyrite with

  18. Tension vein arrays in progressive strain: complex but predictable architecture, and major hosts of ore deposits

    NASA Astrophysics Data System (ADS)

    Laing, W. P.

    2004-06-01

    Most en échelon vein arrays are extensional and can be termed tension vein arrays (TVAs). TVAs in major fault and shear zones (FSZs) are subject to progressive deformation. This deforms the initial TVA (whose geometry is well documented in the literature), via discrete stages; first into progressively more complex architecture, involving folding of the tension veins, then into progressively more simple architecture, ultimately forming pipes. During this progression the TVA axis (new definition) rotates within the shear plane from normal, to parallel, to the displacement vector. The deforming TVA axis has simpler geometry than the complex tension veins, and it can be employed to precisely track the deformation state of the FSZ, its displacement vector, and shear sense, through all the strain stages. Five structural-metasomatic stages are defined by discrete steps in the strain evolution. TVAs are difficult to recognise, and are under-recognised, in ore systems for a number of inherent geological reasons. Orebodies founded on dilation form parallel to the TVA axis, which is also parallel to dilational jogs in the parent FSZ. Orebodies formed early in the FSZ history are normal to the displacement vector, and in progressive shear rotate with the TVA axis toward the displacement vector; orebodies formed late in the FSZ history overprint apparently complex to 'chaotic' vein stockwork, which nevertheless has analysable geometry. TVA-hosted orebodies are not necessarily parallel to the displacement vector of the host FSZ, but occupy elongate orientations over a 90° range within the FSZ. Large orebodies are favourably developed in TVAs in unfoliated FSZs (type 1 shear zones), which may form fluid 'superhighways'. Type 1 shear zones form in predictable circumstances involving particularly host rocktype and crustal position. Strike-slip FSZs possess a downdip TVA axis and are especially able to tap deep crustal fluid. TVA-hosted orebodies form a major deposit style

  19. The exhumed ``Carlin-type'' fossil oil reservoir at Yankee Basin

    NASA Astrophysics Data System (ADS)

    Hulen, Jeffrey B.; Collister, James W.; Stout, Bill; Curtiss, David K.; Dahdah, Nicolas F.

    1998-12-01

    The Carlin-type disseminated gold orebodies of Yankee basin in the southern part of the Alligator Ridge mining district in Nevada contain widespread oil as smears, open-space fillings, and fluid inclusions in syn- and pre-mineral calcite veins. These unusual oils are the relicts of an exhumed and deeply oxidized oil reservoir that encom-passes the orebodies at the crest of a dissected, anticlinal trap. Results of fluid-inclusion microthermometry and organic geochemistry demonstrate that the oils experienced peak paleotemperatures of no more than about 150°C, a temperature unusually low for Carlin-type mineralization, but ideal for the transport, entrapment, and preservation of liquid hydrocarbon. Similar geothermal systems are actively circulating at three of Nevada’s producing oil fields—Grant Canyon, Bacon Flat, and Blackburn. Accordingly, concealed Carlin-type fossil hydrothermal systems of this type, even if subeconomic for gold, could contain commercial concentrations of oil.

  20. Post-depositional tectonic modification of VMS deposits in Iberia and its economic significance

    NASA Astrophysics Data System (ADS)

    Castroviejo, Ricardo; Quesada, Cecilio; Soler, Miguel

    2011-07-01

    The original stratigraphic relationships and structure of VMS deposits are commonly obscured by deformation. This can also affect their economic significance, as shown by several Iberian Pyrite Belt (IPB, SW Iberia) examples. The contrasting rheologic properties of the different lithologies present in an orebody (massive sulphide, feeder stockwork, alteration envelope, volcanic and sedimentary rocks) play a major role in determining its overall behaviour. Variscan thin-skinned tectonics led to stacking of the massive pyrite and stockwork bodies in duplex structures, resulting in local thickening and increased tonnage of minable mineralization. Furthermore, differential mechanical behaviour of the different sulphide minerals localised the detachments along relatively ductile sulphide-rich bands. The result was a geochemical and mineralogical reorganisation of most deposits, which now consist of barren, massive pyrite horses, bounded by base metal-rich ductile shear zones. Metal redistribution was enhanced by mobilisation of the base metal sulphides from the initially impoverished massive pyrite, through pressure-solution processes, to tensional fissures within the already ductile shear zones. In NW Iberia, VMS deposits were also strongly overprinted by the Variscan deformation during emplacement of the Cabo Ortegal and Órdenes allochthonous nappe complexes, but no stacking of the orebodies was produced. Original contacts were transposed, and the orebodies, their feeder zones and the country rock acquired pronounced laminar geometry. In lower-grade rocks (greenschist facies, Cabo Ortegal Complex), solution transfer mechanisms are common in pyrite, which remains in the brittle domain, while chalcopyrite shows ductile behaviour. In higher-grade rocks (amphibolite facies, Órdenes Complex), metamorphic recrystallisation overprints earlier deformation textures. The contrasting behaviour of the IPB and NW Iberian deposits is explained by key factors that affect their

  1. Full Scale Wind Tunnel and Seaplane Tow Channel

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Construction progress, Full Scale entrance cone looking north, exit cone looking south, wind vanes north end, wind vanes north end of east return passage, wind vanes south end of west exit cone looking north east, wind vanes at south end of east exit cone looking north west, entrance cone looking south from north end. Full-Scale Tunnel (FST) entrance cone under construction. Smith DeFrance describes the entrance cone in NACA TR 459 as follows: 'The entrance cone is 75 feet in length and in this distance the cross section changes from a rectangle 72 by 110 feet to a 30 by 60 foot elliptic section. The area reduction in the entrance cone is slightly less than 5:1. The shape of the entrance cone was chosen to give as fas as possible a constant acceleration to the air stream and to retain a 9-foot length of nozzle for directing the flow.' (p. 293)

  2. Near-surface ambient noise tomography in the Baogutu copper deposit area

    NASA Astrophysics Data System (ADS)

    Li, Xin-xin; Li, Qing-chun

    2016-12-01

    The Baogutu copper deposit region is located in the northwestern margin of the Junggar basin, controlled by the NE-SW trend Darbut fault. This region developed mid-late Hercynian (330-320 Ma) intermediate-acid small porphyry bodies. Hosted in the lower carboniferous volcano-sedimentary sequences, the Baogutu porphyry copper deposit has experienced two epochs of fluid metallogenesis after the adakitic magma diagenesis. In the copper deposit area, the orebody distributes in the strata of the Baogutu and Xibeikulasi group, and the ground surface is covered by tuffaceous siltstone. The clear structure of the copper deposit has not been revealed yet. In this paper, we utilize the technique of ambient noise tomography (ANT) to image the phase velocity anomaly maps of different frequencies in the deposit area. Then, we invert the shear (S-) wave velocity structures by using a damped least squares inversion algorithm. The pattern of the tomographic images indicates that the copper deposit mainly distributes in the range of 0.3-0.5 km depth. The major orebody is identified as an obviously high-velocity anomaly. In addition, a small high-velocity anomaly is observed at a depth greater than 0.4 km in the northeast of the study area, and it might associate with another orebody of the Baogutu copper deposit, which has not previously been reported.

  3. Ore mineralogy and sulfur isotope study of the massive sulfide deposit of Filon Norte, Tharsis Mine, Spain

    NASA Astrophysics Data System (ADS)

    Kase, K.; Yamamoto, M.; Nakamura, T.; Mitsuno, C.

    1990-10-01

    The volcanogenic massive sulfide deposit of Filon Norte at Tharsis is hosted by carbonaceous black slate and connected only partly with stockwork veins. The massive ores are usually composed of fine-grained pyrite with subordinate amounts of sphalerite, chalcopyrite, galena and arsenopyrite. Monoclinic pyrrhotite sometimes occurs in massive pyritic ores in the apparently middle and upper horizons of the orebody, and siderite-rich ores are interstratified with compact pyritic ores in the apparently lower horizons. From the occurrence of monoclinic pyrrhotite, together with the FeS contents of sphalerite mostly ranging from 11 to 16 mol %, it is inferred that the sulfide minerals of the massive orebody were precipitated in euxinic muds on the sea-floor at temperatures below 250°C. The negatively shifted, highly variable δ 34S values of the massive ores and their close similarity to those of the underlying black slates strongly suggest that the sulfide sulfur of the massive orebody and the slates is cognate and biogenic.

  4. Geology of the Brick Flat massive sulfide body, Iron Mountain cluster, West Shasta district, California ( USA).

    USGS Publications Warehouse

    Albers, J.P.

    1985-01-01

    The Brick Flat massive sulfide body is one of a group of 8 individual bodies that constitute the Iron Mountain cluster in the S part of the West Shasta district. Before they were separated by postmineral faulting, 5 of the 8 sulfide bodies formed a single large deposit about 1375 m long with a mass of some 23 million metric tons. The pyritic Brick Flat sulfide body is one of the 5 faulted segements of this deposit. The Brick Flat massive sulfide lies within medium phenocryst rhyolite that is characteristic of the ore-bearing middle unit of the Balaklala Rhyolite. It is interpreted to be downfaulted a vertical distance of 75 to 85 m from the Old Mine sulfide-gossan orebody along the N-dipping Camden South fault. It is bounded in turn on its N side by another parallel fault, the Camden North, which drops the orebody down another 75 m to the level of the Richmond orebody. -from Author

  5. The Talgan massive sulfide deposit, the southern Urals, Russia, as an example of subseafloor ore deposition from magmatic fluid

    NASA Astrophysics Data System (ADS)

    Amplieva, E. E.

    2008-10-01

    The sequence of orebody formation at the Talgan massive sulfide deposit; morphology of sulfide orebodies; mineralogy, texture, and structure of ore; chemical composition of minerals; and fluid inclusions and relationships between stable isotopes (S, C, O) in sulfides from ores and carbonate rocks are discussed. The deposit is localized in the Uzel’ga ore field of the northern Magnitogorsk Megazone. The sulfide ore is hosted in the upper felsic sequence of the Middle Devonian Karamalytash Formation, composed of basalt, basaltic andesite, and rhyodacite. Orebodies are irregular lenses lying conformably with host rocks. Pyrite, chalcopyrite, sphalerite, and fahlore are the major ore minerals; galena, bornite, and hematite are of subordinate abundance. Sulfide mineralization bears attributes of deposition under subseafloor conditions. The carbonate and rhyolite interlayers at the roofs of orebodies and the supraore limestone sequence served as screens. Zoning typical of massive sulfide deposits was not established. The study of fluid inclusions has shown that the temperature of the hydrothermal solution varied from 375 to 110°C. δ34S‰ ranges from -2.4 to +3.2‰ in pyrite, from -1.2 to +2.8‰ in chalcopyrite, and from -3.5 to +3.0‰ in sphalerite (CDT). These parameters correspond to an isotopic composition of magmatic sulfur without a notable percentage of sulfate sulfur. δ13C and δ18O of carbonates vary from -18.1 to +5.9‰ (PDB) and from +13.7 to +27.8‰ (SMOW), respectively. The carbon and oxygen isotopic compositions of carbonates from ores and host rocks markedly deviate from the field of marine carbonates; a deep source of carbon is suggested. The results obtained show that the main mass of polysulfide ore at the Talgan deposit was formed beneath the floor of a paleoocean. The ore-forming system was short-lived and its functioning did not give rise to the formation of zonal orebodies. Magmatic fluid played the leading role in mineral formation.

  6. The geology of the Morro Velho gold deposit in the Archean Rio das Velhas greenstone belt, Quadrilátero Ferrífero, Brazil

    USGS Publications Warehouse

    Vial, Diogenes Scipioni; DeWitt, Ed; Lobato, Lydia Maria; Thorman, Charles H.

    2007-01-01

    The Morro Velho gold deposit, Quadrilátero Ferrífero region, Minas Gerais, Brazil, is hosted by rocks at the base of the Archean Rio das Velhas greenstone belt. The deposit occurs within a thick carbonaceous phyllite package, containing intercalations of felsic and intermediate volcaniclastic rocks and dolomites. Considering the temporal and spatial association of the deposit with the Rio das Velhas orogeny, and location in close proximity to a major NNW-trending fault zone, it can be classified as an orogenic gold deposit. Hydrothermal activity was characterized by intense enrichment in alteration zones of carbonates, sulfides, chlorite, white mica±biotite, albite and quartz, as described in other Archean lode-type gold ores. Two types of ore occur in the deposit: dark gray quartz veins and sulfide-rich gold orebodies. The sulfide-rich orebodies range from disseminated concentrations of sulfide minerals to massive sulfide bodies. The sulfide assemblage comprises (by volume), on average, 74% pyrrhotite, 17% arsenopyrite, 8% pyrite and 1% chalcopyrite. The orebodies have a long axis parallel to the local stretching lineation, with continuity down the plunge of fold axis for at least 4.8 km. The group of rocks hosting the Morro Velho gold mineralization is locally referred to as lapa seca. These were isoclinally folded and metamorphosed prior to gold mineralization. The lapa seca and the orebodies it hosts are distributed in five main tight folds related to F1 (the best examples are the X, Main and South orebodies, in level 25), which are disrupted by NE- to E-striking shear zones. Textural features indicate that the sulfide mineralization postdated regional peak metamorphism, and that the massive sulfide ore has subsequently been neither metamorphosed nor deformed. Lead isotope ratios indicate a model age of 2.82 ± 0.05 Ga for both sulfide and gold mineralization. The lapa seca are interpreted as the results of a pre-gold alteration process and may be

  7. Interior, equipment room, weather support area (from July, 1968 drawing) ...

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

    Interior, equipment room, weather support area (from July, 1968 drawing) at north end of display area, looking west. Window looks south towards the main console - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  8. 2. VIEW, LOOKING EAST, SHOWING J. CLARK SALYER NATIONAL WILDLIFE ...

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

    2. VIEW, LOOKING EAST, SHOWING J. CLARK SALYER NATIONAL WILDLIFE REFUGE, JUST EAST OF WESTHOPE, NORTH DAKOTA (THE NORTH END OF THE REFUGE JUST SOUTH OF DAM 357 AND THE CANADIAN BORDER) - J. Clark Salyer National Wildlife Refuge Dams, Along Lower Souris River, Kramer, Bottineau County, ND

  9. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Snake Island, Texas City, Texas... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety zone... Turning Basin west of Snake Island; (3) The area of Texas City Channel from the north end of the...

  10. PUMP SETS NO. 5 AND NO. 4. Each pump set ...

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

    PUMP SETS NO. 5 AND NO. 4. Each pump set consists of a Worthington Pump and a General Electric motor - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Flame Deflector Water System, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  11. White Sands Space Harbor Area 1, Microwave Scanning Beam Landing ...

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

    White Sands Space Harbor Area 1, Microwave Scanning Beam Landing Ground Stations, 1,500' to the south of the north end of Runway 17/35; 1,500' to the west of the east end of Runway 23/05; and 1,500' southwest of the northeast end of Runway 20/02., White Sands, Dona Ana County, NM

  12. 17. Interior view of courtroom looking towards judge's bench; showing ...

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

    17. Interior view of courtroom looking towards judge's bench; showing built in linear seating on both ends of room, clerical desk and equipment, through wall air conditioning units, exterior windows and door; north end of west wing on top floor; view to northwest. - Ellsworth Air Force Base, Group Administration & Secure Storage Building, 2372 Westover Avenue, Blackhawk, Meade County, SD

  13. 18. Interior view of large unoccupied meeting/gathering room looking towards ...

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

    18. Interior view of large unoccupied meeting/gathering room looking towards small stage and opened doorway to exterior vestibule; showing through wall air conditioning unit; north end of east wing on main floor; view to southwest. - Ellsworth Air Force Base, Group Administration & Secure Storage Building, 2372 Westover Avenue, Blackhawk, Meade County, SD

  14. 16. Detail view of the scale area at the north ...

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

    16. Detail view of the scale area at the north end of the 1937 main section, looking east-northeast; the original office is at th left, and the scale at the right - Ewing Livestock Market, South side of First Avenue North, 500 feet west of Route 724, Ewing, Lee County, VA

  15. 77 FR 514 - Notice of Availability of the Record of Decision for the North Steens 230 Kilovolt Transmission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-05

    ..., Echanis, LLC, a subsidiary of Columbia Energy Partners, LLC, filed right-of-way (ROW) applications for... Project, located on private land on the north end of Steens Mountain, with Harney Electric Cooperative's... Project substation, south of Diamond, Oregon and connect to Harney Electric Cooperative's existing...

  16. 58. DETAIL OF SLC3W UMBILICAL MAST CONTROL PANEL LOCATED ON ...

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

    58. DETAIL OF SLC-3W UMBILICAL MAST CONTROL PANEL LOCATED ON WEST SIDE OF MAST TRENCH APPROXIMATELY HALF WAY BETWEEN THE NORTH END OF TRENCH AND LAUNCHER - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  17. 33 CFR 110.155 - Port of New York.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... of Hart Island; west of Hart Island; and northwest of a line extending from Hart Island Light to... southwest end of Hart Island; northwest of a line ranging from the water tank at the north end of Davids... a line ranging from Fort Totten flagpole to Hart Island Light; and south of Anchorage No. 4....

  18. 33 CFR 110.155 - Port of New York.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... of Hart Island; west of Hart Island; and northwest of a line extending from Hart Island Light to... southwest end of Hart Island; northwest of a line ranging from the water tank at the north end of Davids... a line ranging from Fort Totten flagpole to Hart Island Light; and south of Anchorage No. 4....

  19. 43. 'Firing Pier, Third and Fourth Floors and Roof Plan,' ...

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

    43. 'Firing Pier, Third and Fourth Floors and Roof Plan,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3869-46, Y&D Drawing 190843. Scale 1/4' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  20. 39. 'Firing Pier, First Floor Plan, Section No. 4,' submitted ...

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

    39. 'Firing Pier, First Floor Plan, Section No. 4,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3865-46, Y&D Drawing 190839. Scale 1/4' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  1. 33. 'Firing Pier, Elevations, North & South,' submitted 29 December ...

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

    33. 'Firing Pier, Elevations, North & South,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3870-46, Y&D Drawing 190844. Scales as noted. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  2. 41. 'Firing Pier, Second Floor Plan, Section No. 2,' submitted ...

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

    41. 'Firing Pier, Second Floor Plan, Section No. 2,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3867-46, Y&D Drawing 190841. Scale 1/4' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  3. 32. 'Firing Pier, Elevation, West,' submitted 29 December 1941 by ...

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

    32. 'Firing Pier, Elevation, West,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3872-46, Y&D Drawing 190846. Scale 1/8' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  4. 19. Interior first level view looking north within forward (north) ...

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

    19. Interior first level view looking north within forward (north) section of firing pier. Objects pictured include torpedo cart (left), floor-mounted roller tray (extending to lower right), and (at center rear), deck-type firing tube. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  5. 40. 'Firing Pier, Second Floor Plan, Section No. 1,' submitted ...

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

    40. 'Firing Pier, Second Floor Plan, Section No. 1,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3866-46, Y&D Drawing 190840. Scale 1/4' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  6. 42. 'Firing Pier, Second Floor Plan, Section No. 3,' submitted ...

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

    42. 'Firing Pier, Second Floor Plan, Section No. 3,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3868-46, Y&D Drawing 190842. Scale 1/4' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  7. 37. 'Firing Pier, First Floor Plan, Section No. 2,' submitted ...

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

    37. 'Firing Pier, First Floor Plan, Section No. 2,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3863-46, Y&D Drawing 190837. Scale 1/4' = 1. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  8. 34. 'Firing Pier, Longitudinal Sectional Elevation, Looking East,' submitted 29 ...

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

    34. 'Firing Pier, Longitudinal Sectional Elevation, Looking East,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3873-46, Y&D Drawing 190847. Scale 1/8' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  9. 38. 'Firing Pier, First Floor Plan, Section No. 3,' submitted ...

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

    38. 'Firing Pier, First Floor Plan, Section No. 3,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3864-46, Y&D Drawing 190838. Scale 1/4' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  10. 36. 'Firing Pier, First Floor Plan, Section No. 1,' submitted ...

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

    36. 'Firing Pier, First Floor Plan, Section No. 1,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3862-46, Y&D Drawing 190836. Scale 1/4' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  11. 14. View south from first level roof of firing pier. ...

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

    14. View south from first level roof of firing pier. Pitched corrugated metal roof marks location of the frame approach connecting the firing pier to the shop (shown in left distance). - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  12. 31. 'Firing Pier, Elevation, East,' submitted 29 December 1941 by ...

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

    31. 'Firing Pier, Elevation, East,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3871-46, Y&D Drawing 190845. Scale 1/8' = 1' - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  13. 35. 'Firing Pier, Cross Sections, Looking South,' submitted 29 December ...

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

    35. 'Firing Pier, Cross Sections, Looking South,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3874-46, Y&D Drawing 190848. Scale 1/8' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  14. 8. Interior view of unoccupied office space; showing exterior windows, ...

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

    8. Interior view of unoccupied office space; showing exterior windows, exterior door at far left, and opened doorway to corridor; north end of east wing on top floor; view to southeast. - Ellsworth Air Force Base, Group Administration & Secure Storage Building, 2372 Westover Avenue, Blackhawk, Meade County, SD

  15. Currents and Undercurrents: An Administrative History of Lake Roosevelt National Recreation Area.

    ERIC Educational Resources Information Center

    McKay, Kathryn L.; Renk, Nancy F.

    The 1,259-mile Columbia River flows out of Canada and across eastern Washington state, forming the border between Washington and Oregon. In 1941 the federal government dammed the Columbia River at the north end of Grand Coulee, creating a man-made reservoir named Lake Roosevelt that inundated homes, farms, and businesses, and disrupted the lives…

  16. 45. 1915 CLOTH ROOM ADJACENT TO PICKER ROOM, SECOND FLOOR, ...

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

    45. 1915 CLOTH ROOM ADJACENT TO PICKER ROOM, SECOND FLOOR, NORTH END OF MILL NO. 2, WALL ON LEFT DIVIDING CLOTH ROOM ADDED LATER (PROBABLY C. 1970s). - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  17. 80. DETAIL OF TYPICAL PRESSURE GAUGE IN NITROGEN AND HELIUM ...

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

    80. DETAIL OF TYPICAL PRESSURE GAUGE IN NITROGEN AND HELIUM STORAGE AND TRANSFER CONTROL SKIDS ON NORTH END OF SLC-3W FUEL APRON - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  18. 19. TRAVELING CRANE ATOP SUPERSTRUCTURE, FROM RUN LINE DECK. Looking ...

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

    19. TRAVELING CRANE ATOP SUPERSTRUCTURE, FROM RUN LINE DECK. Looking up to north northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  19. Airfield setting of Facility Nos. 175 and 176, taken from ...

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

    Airfield setting of Facility Nos. 175 and 176, taken from north end of Ford Island Runway, with landplane hangars on the right - U.S. Naval Base, Pearl Harbor, Landplane Hangar Type, Wasp Boulevard and Gambier Bay Street, Pearl City, Honolulu County, HI

  20. FACILITY 72, INTERIOR. 15LIGHT DOUBLE DOORS WITH 15LIGHT SIDELIGHTS AND ...

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

    FACILITY 72, INTERIOR. 15-LIGHT DOUBLE DOORS WITH 15-LIGHT SIDELIGHTS AND 2-LIGHT TRANSOM. LIVING ROOM BEYOND. VIEW FACING NORTH-NORTHEAST. - U.S. Naval Base, Pearl Harbor, Naval Housing Area Makalapa, Senior Officers' Quarters Type C, North end of Makalapa Drive, Pearl City, Honolulu County, HI

  1. 14. INTERIOR OF BEDROOM NUMBER TWO SHOWING FLOOR TO CEILING ...

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

    14. INTERIOR OF BEDROOM NUMBER TWO SHOWING FLOOR TO CEILING BUILT-IN CLOSET OCCUPING ENTIRE NORTH END OF ROOM, AND 6-LIGHT OVER 1-LIGHT SASH WINDOW ON EAST WALL. VIEW TO NORTH. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  2. 15. Interior firstlevel view looking north within rear section of ...

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

    15. Interior first-level view looking north within rear section of firing pier. Debris includes a junked torpedo firing tube mounted on a dolly. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  3. 2. UPSTREAM SIDE OF DAM AND BRIDGE WITH ABANDONED SAN ...

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

    2. UPSTREAM SIDE OF DAM AND BRIDGE WITH ABANDONED SAN TAN FLOOD-WATER HEADGATE IN FOREGROUND. TAKEN FROM NORTH END OF DAM - San Carlos Irrigation Project, Sacaton Dam & Bridge, Gila River, T4S R6E S12/13, Coolidge, Pinal County, AZ

  4. 16. View of riveted gusset plate connection between compression diagonal, ...

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

    16. View of riveted gusset plate connection between compression diagonal, tension diagonal, and lateral brace at center of 4th panel from north end of west truss of north span, looking from the east - Bridge No. 4900, Spanning Root River at Trunk Highway 16, Rushford, Fillmore County, MN

  5. 15. View showing junction of compression diagonal, vertical member, tension ...

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

    15. View showing junction of compression diagonal, vertical member, tension diagonal, and lower chord members between 5th and 6th panels from north end of north span, looking from the east - Bridge No. 4900, Spanning Root River at Trunk Highway 16, Rushford, Fillmore County, MN

  6. 45. 'Replace Starboard Elevator and Repairs, Gould Island, Building No. ...

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

    45. 'Replace Starboard Elevator and Repairs, Gould Island, Building No. 35,' approved 26 July 1981, NUSC Drawing No. 80-67, NAV. FAC. Drawing No. 2,047,203. Scales as noted. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  7. 6. Historic American Buildings Survey (Fed.) Stanley P. Mixon, Photographer ...

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

    6. Historic American Buildings Survey (Fed.) Stanley P. Mixon, Photographer March 18, 1940, (F) EXT. DETAIL VIEW OF NORTH END GABLES, KITCHEN WING IN FOREGROUND. - Wyckoff-Bennett House, Kings Highway & 1669 East Twenty-second Street, Brooklyn, Kings County, NY

  8. 18. Photocopy of photograph. Horgan, date unknown. Original negative can ...

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

    18. Photocopy of photograph. Horgan, date unknown. Original negative can be found in D & H collection of the Anthracite Heritage Museum, Scranton, Pennsylvania. DETAIL VIEW OF SLUSH TROUGH FROM BREAKER NO. 2 TO BOREHOLE UNDER NORTH END OF BOILER HOUSE NO. 2, LOOKING SOUTH - Marvine Colliery, Breaker No. 2, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA

  9. 1. View from Roundhouse roof showing remains of gable (north) ...

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

    1. View from Roundhouse roof showing remains of gable (north) end and clerestory monitor of Machine Shop. - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Machine Shop, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  10. 1. EXTERIOR VIEW OF BOILER HOUSE FROM SOUTHWEST. THE BOILER ...

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

    1. EXTERIOR VIEW OF BOILER HOUSE FROM SOUTHWEST. THE BOILER HOUSE WAS USED FOR HEATING THE MILL; HYDRO-ELECTRIC POWER FOR PRODUCTION WAS PURCHASED FROM THE COLUMBUS LIGHT & POWER COMPANY. NORTH END OF 1924 MILL TO RIGHT, c. 1970 WINDOWLESS WEAVE ROOM ADDITION TO LEFT. - Stark Mill, Boiler House, 117 Corinth Road, Hogansville, Troup County, GA

  11. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Turning Basin west of Snake Island; (3) The area of Texas City Channel from the north end of the Turning... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Snake Island, Texas City, Texas... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety...

  12. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Turning Basin west of Snake Island; (3) The area of Texas City Channel from the north end of the Turning... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Snake Island, Texas City, Texas... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety...

  13. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Turning Basin west of Snake Island; (3) The area of Texas City Channel from the north end of the Turning... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Snake Island, Texas City, Texas... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety...

  14. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Turning Basin west of Snake Island; (3) The area of Texas City Channel from the north end of the Turning... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Snake Island, Texas City, Texas... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety...

  15. 1. OVERVIEW OF BUILDING 105 SHOWING LOCAL SETTING. ROOF, NORTH ...

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

    1. OVERVIEW OF BUILDING 105 SHOWING LOCAL SETTING. ROOF, NORTH END, AND WEST SIDE OF BUILDING 105 ARE VISIBLE AT LEFT PHOTO CENTER BEHIND UTILITY POLE. ROOF AND WEST END OF BUILDING 110 ARE VISIBLE AT PHOTO RIGHT BEHIND TREES. VIEW TO SOUTH FROM STREET ABOVE HOUSES. - Big Creek Hydroelectric System, Powerhouse 8, Operator Cottage, Big Creek, Big Creek, Fresno County, CA

  16. 4. ARAI Shop and maintenance building ARA627. West side and ...

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

    4. ARA-I Shop and maintenance building ARA-627. West side and north end. Camera facing southeast. Shows original (lower roofed section) and later addition. Metal building next to south end is related to decontamination and demolition activities. Ineel photo no. 1-7. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

  17. 9. ARAI Shop and maintenance building ARA627 interior view. Metal ...

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

    9. ARA-I Shop and maintenance building ARA-627 interior view. Metal roll-up door on north end (rear) of building. Camera facing northeast. Ineel photo no. 1-12. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

  18. Chemours Pompton Lakes Works Site, Pompton Lakes, NJ

    EPA Pesticide Factsheets

    E.I. DuPont De Nemours & Company manufactured explosives on this 570-acre site at the north end of Pompton Lakes, New Jersey from 1902-1994. Land use in the vicinity is primarily residential and commercial, but also includes undeveloped areas, an interstat

  19. Interior sump/sewerage room from entry, view facing northeast U.S. ...

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

    Interior sump/sewerage room from entry, view facing northeast - U.S. Naval Base, Pearl Harbor, Dry Dock No. 1, Pumpwell, By-Pass Valve & Saltwater Pumphouse, North end of Fifth Street, between Dry Dock No. 1 & Facility GD2 , Pearl City, Honolulu County, HI

  20. Interior of sump/sewerage room looking up four levels, ladder on ...

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

    Interior of sump/sewerage room looking up four levels, ladder on pipe, view facing southwest - U.S. Naval Base, Pearl Harbor, Dry Dock No. 1, Pumpwell, By-Pass Valve & Saltwater Pumphouse, North end of Fifth Street, between Dry Dock No. 1 & Facility GD2 , Pearl City, Honolulu County, HI

  1. Interior view of pump 4, taken from stairs looking down, ...

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

    Interior view of pump 4, taken from stairs looking down, doorway to sump/sewerage room at bottom, tapered stairs, view facing east - U.S. Naval Base, Pearl Harbor, Dry Dock No. 1, Pumpwell, By-Pass Valve & Saltwater Pumphouse, North end of Fifth Street, between Dry Dock No. 1 & Facility GD2 , Pearl City, Honolulu County, HI

  2. 23. (Credit JTL) View looking ENE at west end of ...

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

    23. (Credit JTL) View looking ENE at west end of station. End addition houses chlorination equipment; to extreme right is north end of filter building built in 1942. - McNeil Street Pumping Station, McNeil Street & Cross Bayou, Shreveport, Caddo Parish, LA

  3. 78 FR 43189 - Birch Power Company; Notice of Application Tendered for Filing With the Commission and Soliciting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... should note the Commission's policy that agencies that cooperate in the preparation of the environmental... . You must include your name and contact information at the end of your comments. For assistance, please... 900-foot-long intake channel; (2) a powerhouse adjacent to the north end of the existing...

  4. 21. VALVES, GAUGES, AND SEVERAL TYPES OF LIGHTING ALONG ROAD ...

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

    21. VALVES, GAUGES, AND SEVERAL TYPES OF LIGHTING ALONG ROAD AT SOUTH REAR OF TEST STAND 1-A. RP1 TANK FARM IN MIDDLE DISTANCE. Looking northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  5. 22. STEAM PLANT TURBINE DECK FROM SOUTH END OF BUILDING, ...

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

    22. STEAM PLANT TURBINE DECK FROM SOUTH END OF BUILDING, SHOWING TOPS OF DIESEL ENGINES AT FAR NORTH END, PRIOR TO INSTALLATION OF STEAM UNIT NO. 4. Ca. 1948 - Crosscut Steam Plant, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  6. 78 FR 26345 - York Haven Power Company, LLC; Notice of Application Accepted for Filing, Soliciting Motions To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-06

    ... headrace wall, main dam, east channel dam, powerhouse, and forebay bulkhead. The stone masonry headrace wall extends 3,000 feet upstream from the north end of the powerhouse and, with an average height of 20... wall, 155 feet long, extends west from the south end of the powerhouse to the transformer...

  7. 78 FR 13621 - Forest Service

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-28

    ... northern wall and gradually filling the quarry to approximate original contours. The Butterfield quarry... general site monitoring will be reclaimed. Final sloping of quarry walls, backfilled areas, and overburden... the water guzzler for bighorn sheep near the north end of the Sentinel Quarry. 7. Continue support...

  8. 12. INTERIOR VIEW TO THE NORTH OF THE RESTROOM AND ...

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

    12. INTERIOR VIEW TO THE NORTH OF THE RESTROOM AND UTILITY ROOM AT THE NORTH END OF THE MAIN ENTRANCE HALLWAY OF THE ADMINISTRATION AREA. - Nevada Test Site, Reactor Maintenance Assembly & Dissassembly Facility, Area 25, Jackass Flats, Junction of Roads F & G, Mercury, Nye County, NV

  9. 47. Detail of gears for steam powered Marine Railway #1, ...

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

    47. Detail of gears for steam powered Marine Railway #1, and drive equipment for Railways #l and #2, Marine Railway Headhouse, ground floor, north end, drive gears in foreground, pulling gears for Railway # 1 in background. - Thames Tow Boat Company, Foot of Farnsworth Street, New London, New London County, CT

  10. 4. VIEW OF A DRYLAID ROCK WALL (TY31772) ON THE ...

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

    4. VIEW OF A DRY-LAID ROCK WALL (TY-3177-2) ON THE KINGS CANYON ROAD WHERE BLADING AND GRADING WILL OCCUR. LOCATED AT MILEPOST 0.07 (ACCORDING TO THE ARCHAEOLOGICAL SITE RECORD FOR TY-3177). TAKEN FROM THE NORTH END OF THE WALL, FACING SOUTH 24ø WEST (214ø). - Kings Canyon Road, Carson City, Carson City, NV

  11. The auditorium is visible in the center distance, beyond the ...

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

    The auditorium is visible in the center distance, beyond the north end of the administration building, in the shadow at left, and beyond the west end of the life sciences building at the right. - San Bernardino Valley College, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  12. Courtyard between the library, at left, and the life sciences ...

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

    Courtyard between the library, at left, and the life sciences building, at right. The north end of the administration building is just out of view to the right. - San Bernardino Valley College, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  13. 2. VIEW OF WEST FACE OF LAUNCH OPERATIONS BUILDING. BUNKER ...

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

    2. VIEW OF WEST FACE OF LAUNCH OPERATIONS BUILDING. BUNKER PERISCOPE VISIBLE ON NORTH END OF ROOF. ESCAPE TUNNEL AND CABLE SHED VISIBLE ON NORTH FACE. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  14. 9. BUILDING 8769, EAST REAR AND NORTH SIDE, TEST STAND ...

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

    9. BUILDING 8769, EAST REAR AND NORTH SIDE, TEST STAND AT RIGHT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  15. 10. OBSERVATION POST NO. 3, WEST OF TEST STAND 1A. ...

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

    10. OBSERVATION POST NO. 3, WEST OF TEST STAND 1-A. SOUTH SIDE AND EAST FRONT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  16. 5. BUILDING 8768, SOUTH SIDE AND EAST REAR. TEST STAND ...

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

    5. BUILDING 8768, SOUTH SIDE AND EAST REAR. TEST STAND 1A AT LEFT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  17. 11. OBSERVATION POST NO. 3, NORTH SIDE AND WEST REAR, ...

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

    11. OBSERVATION POST NO. 3, NORTH SIDE AND WEST REAR, TEST STAND AT RIGHT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  18. 3. BUILDING 8767, NORTH REAR AND WEST SIDE, TEST STAND ...

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

    3. BUILDING 8767, NORTH REAR AND WEST SIDE, TEST STAND 1-A AT FAR RIGHT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  19. 25. Photocopy of a photograph (original print in the collection ...

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

    25. Photocopy of a photograph (original print in the collection of the New Hampshire Water Resources Board, Concord, New Hampshire) 1927, photographer unknown 2 3/8 X 4 inch negative VIEW OF THE NORTH END OF THE OLD TIMBER DAM AT DAM SITE No. 3 - Claremont Village Industrial District, Between B, Claremont, Sullivan County, NH

  20. Interior, main room , Burton Park Club House, view to ...

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

    Interior, main room , Burton Park Club House, view to south from north end door (90mm lens). Front doors visible at left, fireplace at right, while kingpost trusses supports the roof. - Burton Park, Club House & Amphitheater, Adjacent ot south end of Chestnut Avenue, San Carlos, San Mateo County, CA

  1. 33 CFR 110.145 - Narragansett Bay, R.I.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... north end of the wharf at Beaver Head. (i) Temporary floats or buoys for marking anchors or moorings in.... In the central and southern portion of Dutch Island Harbor, north of a line ranging 106° from Beaver Head Point Shoal Buoy 2 toward the Jamestown standpipe; east of a line ranging 14° from Beaver...

  2. 33 CFR 110.145 - Narragansett Bay, R.I.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... north end of the wharf at Beaver Head. (i) Temporary floats or buoys for marking anchors or moorings in.... In the central and southern portion of Dutch Island Harbor, north of a line ranging 106° from Beaver Head Point Shoal Buoy 2 toward the Jamestown standpipe; east of a line ranging 14° from Beaver...

  3. 30. XX byproducts building (containing coke gas compressors at north ...

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

    30. XX by-products building (containing coke gas compressors at north end, ammonia stills in south end), #20 coal conveyor jutting out of top on east side, continuing out west side to bunker. Looking south/southeast - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  4. 22. TRANSPORTING STEEL FLOOR PLATES ON HAND CART TO NORTH ...

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

    22. TRANSPORTING STEEL FLOOR PLATES ON HAND CART TO NORTH END OF BRIDGE. NOTE RETAINING ANGLE FOR SURFACING AT CUT-SIDE EDGE OF FLOOR PLATES. NOTE TUNNELS IN TOP OF ROCK FACE FOR MAIN CABLES - Kaibab Trail Suspension Bridge, Spanning Colorado River, Grand Canyon, Coconino County, AZ

  5. DETAIL OF STEEL PLATE SET INTO THE CONCRETE SLAB OF ...

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

    DETAIL OF STEEL PLATE SET INTO THE CONCRETE SLAB OF THE NORTH END OF THE ABOVE-GROUND PORTION. VIEW FACING NORTH - U.S. Naval Base, Pearl Harbor, Ford Island 5-Inch Antiaircraft Battery, Battery Command Center, Ford Island, Pearl City, Honolulu County, HI

  6. 14. DETAIL EXTERIOR VIEW LOOKING EAST AT DOWNSTREAM SIDE OF ...

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

    14. DETAIL EXTERIOR VIEW LOOKING EAST AT DOWNSTREAM SIDE OF NORTH END OF DAM/SPILLWAY; GANTRY CRANE ABOVE MOVABLE STONEY GATE IS VISIBLE IN CENTER BACKGROUND; FISH LADDER ON WASHINGTON SHORE IS VISIBLE IN FOREGROUND. - Bonneville Project, Bonneville Dam, Columbia River, Bonneville, Multnomah County, OR

  7. 30. 'Gould Island Facilities, General Plan,' submitted 29 December 1941 ...

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

    30. 'Gould Island Facilities, General Plan,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3859-46, Y&D Drawing 190833. Scales 1' = 50' and 1' = 10'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  8. Detail, east porch, view to southsouthwest. This was originally an ...

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

    Detail, east porch, view to south-southwest. This was originally an open porch (note chamfered porch post in center, enclosed at unknown date. Note also 6/6 windows, which appear only here and in north end of second floor. - Drew-Sherwood Farm, House, 7927 Elk Grove Boulevard, Elk Grove, Sacramento County, CA

  9. 13. DETAIL SHOWING OXYGEN (LEFT) AND HYDROGEN (RIGHT) PREVALVES ON ...

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

    13. DETAIL SHOWING OXYGEN (LEFT) AND HYDROGEN (RIGHT) PREVALVES ON SECOND DECK OF SUPERSTRUCTURE, ABOVE THE ENGINE. Looking northwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  10. 20. DECOMMISIONED HYDROGEN TANK IN FORMER LIQUID OXYGEN STORAGE AREA, ...

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

    20. DECOMMISIONED HYDROGEN TANK IN FORMER LIQUID OXYGEN STORAGE AREA, BETWEEN TEST STAND 1-A AND INSTRUMENTATION AND CONTROL BUILDING. Looking northwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  11. 12. DETAIL SHOWING EAST SIDE OF THE OXYGEN AND HYDROGEN ...

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

    12. DETAIL SHOWING EAST SIDE OF THE OXYGEN AND HYDROGEN PRE-VALVE DECK (2ND LEVEL). Looking south. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  12. 15. DETAIL SHOWING HYDROGEN (LEFT) AND OXYGEN (RIGHT) SPHERICAL TANKS ...

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

    15. DETAIL SHOWING HYDROGEN (LEFT) AND OXYGEN (RIGHT) SPHERICAL TANKS ON RUN LINE DECK, THIRD LEVEL. DARK TONED PIPING IS THE FIRE EXTINGUISHING SYSTEM. Looking south southwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  13. 6. CABLE RACK, MEZZANINE LEVEL, INTERIOR OF TEST STAND 1A. ...

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

    6. CABLE RACK, MEZZANINE LEVEL, INTERIOR OF TEST STAND 1A. Looking south from north wall of terminal room. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  14. 7. SOUTH REAR. Looking northwest from corner of the Instrumentation ...

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

    7. SOUTH REAR. Looking northwest from corner of the Instrumentation and Control Building (Building 8762). - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  15. 2. NORTH FRONT, FROM SUPERSTRUCTURE TO FLAME DEFLECTOR. Looking south ...

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

    2. NORTH FRONT, FROM SUPERSTRUCTURE TO FLAME DEFLECTOR. Looking south southwest from Observation Post No. 1 (Building 8767). - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  16. ONE MILLION GALLON WATER TANK, PUMP HEADER PIPE (AT LEFT), ...

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

    ONE MILLION GALLON WATER TANK, PUMP HEADER PIPE (AT LEFT), HEADER BYPASS PIPE (AT RIGHT), AND PUMPHOUSE FOUNDATIONS. Looking northeast - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Flame Deflector Water System, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  17. 18. CROWS NEST ATOP SUPERSTRUCTURE. Looking up from northeast corner ...

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

    18. CROWS NEST ATOP SUPERSTRUCTURE. Looking up from northeast corner of run line deck. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  18. 1. TERMINAL ROOM, INTERIOR, SHOP LEVEL, SHOWING FIRE EXTINGUISHING SYSTEM ...

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

    1. TERMINAL ROOM, INTERIOR, SHOP LEVEL, SHOWING FIRE EXTINGUISHING SYSTEM PIPES AND VALVES AT LEFT. Looking southeast from entrance to terminal room. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  19. 2. TERMINAL ROOM, SHOP LEVEL INTERIOR, SHOWING MEZZANINE LEVEL CABLE ...

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

    2. TERMINAL ROOM, SHOP LEVEL INTERIOR, SHOWING MEZZANINE LEVEL CABLE RACK AT UPPER RIGHT. Looking north. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  20. 10. DETAIL SHOWING THRUST MEASURING SYSTEM. Looking up from the ...

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

    10. DETAIL SHOWING THRUST MEASURING SYSTEM. Looking up from the test stand deck to east. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  1. 9. WEST SIDE, TEST STAND AND SUPERSTRUCTURE. TEST STAND 1B ...

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

    9. WEST SIDE, TEST STAND AND SUPERSTRUCTURE. TEST STAND 1-B IN DISTANCE. Looking east. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  2. 3. DETAIL OF NORTH FRONT AND WEST SIDE, WITH SUPERSTRUCTURE, ...

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

    3. DETAIL OF NORTH FRONT AND WEST SIDE, WITH SUPERSTRUCTURE, FROM NEAR OBSERVATION POST NO. 3. Looking south southeast from below. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  3. 5. METAL SHOP ROOM (AREA 108 ON PLAN CA236R36). Looking ...

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

    5. METAL SHOP ROOM (AREA 108 ON PLAN CA-236-R-36). Looking northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  4. GENERAL VIEW OF PUMPHOUSE FOUNDATIONS, ALSO SHOWING THREE PUMPS STILL ...

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

    GENERAL VIEW OF PUMPHOUSE FOUNDATIONS, ALSO SHOWING THREE PUMPS STILL ON THE PAD, AND THE ELECTRICAL SUBSTATION IN LEFT MIDDLE DISTANCE - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Flame Deflector Water System, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  5. 3. SHOP AREA. Looking west into storage cage from near ...

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

    3. SHOP AREA. Looking west into storage cage from near northeast corner of room. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  6. RP1 (KEROSENE) STORAGE TANKS ON HILLSIDE EAST OF TEST STAND ...

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

    RP1 (KEROSENE) STORAGE TANKS ON HILLSIDE EAST OF TEST STAND 1-B. THIS TANK FARM SERVES BOTH TEST STANDS 1-A AND 1-B - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Combined Fuel Storage Tank Farm, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  7. 24. SATURN V Fl ENGINE TEST FIRING ON TEST STAND ...

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

    24. SATURN V F-l ENGINE TEST FIRING ON TEST STAND 1A. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  8. 36 CFR 293.16 - Special provisions governing the Boundary Waters Canoe Area Wilderness, Superior National Forest...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the Boundary Waters Canoe Area Wilderness, Superior National Forest, Minnesota. 293.16 Section 293.16... § 293.16 Special provisions governing the Boundary Waters Canoe Area Wilderness, Superior National... the narrows at the north end of Jackfish Bay and north of a point on the International...

  9. 36 CFR 293.16 - Special provisions governing the Boundary Waters Canoe Area Wilderness, Superior National Forest...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the Boundary Waters Canoe Area Wilderness, Superior National Forest, Minnesota. 293.16 Section 293.16... § 293.16 Special provisions governing the Boundary Waters Canoe Area Wilderness, Superior National... the narrows at the north end of Jackfish Bay and north of a point on the International...

  10. 19. Jet Lowe, Photographer, June 1979. SECOND FLOOR, INTERIOR, NORTH ...

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

    19. Jet Lowe, Photographer, June 1979. SECOND FLOOR, INTERIOR, NORTH END, SHOWING REMAINS OF FLOUR AND WHEAT BINS, PLATFORM FLOUR SIFTERS, D.C. GENERATOR FROME, SALEM MACHINE WORKS FLOUR MIXER AND SPROUT, WALDRON AND CO. CENTRIFUGAL REEL. - Womack's Mill, Yanceyville, Caswell County, NC

  11. 11. Interior view of first floor of 1922 north section, ...

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

    11. Interior view of first floor of 1922 north section, showing east wall and windows at far north end of building. Camera pointed E. Rear of building is partially visible on far left. - Puget Sound Naval Shipyard, Pattern Shop, Farragut Avenue, Bremerton, Kitsap County, WA

  12. 9. DETAIL VIEW OF INTERIOR OF BREAKER, FIRST FLOOR, DEPICTING ...

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

    9. DETAIL VIEW OF INTERIOR OF BREAKER, FIRST FLOOR, DEPICTING CHUTES AND ELECTRIC MOTOR, LOOKING EAST-SOUTHEAST FROM ELEVATED PLATFORM AT NORTH END - Marvine Colliery, Breaker No. 2, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA

  13. 4. Historic American Buildings Survey PHOTOCOPY CA. 1916 OF FRENCH ...

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

    4. Historic American Buildings Survey PHOTOCOPY CA. 1916 OF FRENCH ROOM LOOKING AT NORTH END OF ROOM. WALLS COVERED IN SILK WITH HAND- EMBROIDERED APPLIQUES. NOTE CARVINGS AND MOLDINGS IN WHITE GUM WOODWORK. FLOORS ARE PARQUET. Original in Collections of Marian College - James A. Allison Mansion, 3200 Coldspring Road, Indianapolis, Marion County, IN

  14. 76 FR 4818 - Drawbridge Operation Regulation; Old Brazos River, Freeport, Brazoria County, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-27

    ... operation of the Union Pacific Railroad Swing Span Bridge across the Old Brazos River, mile 4.4, at Freeport... February 10, 2011 until 7 a.m. on February 16, 2011. This deviation will allow the swing span of the bridge to remain in the closed-to-navigation position in order for the north end of the swing span to be...

  15. Interior view of double steel entry doors at bottom of ...

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

    Interior view of double steel entry doors at bottom of stair leading to street level, note painted glass panes on upper portion of doors, view facing southeast - U.S. Naval Base, Pearl Harbor, Dry Dock No. 1, Pumpwell, By-Pass Valve & Saltwater Pumphouse, North end of Fifth Street, between Dry Dock No. 1 & Facility GD2 , Pearl City, Honolulu County, HI

  16. 11. Connection of upright structural members to top of arch ...

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

    11. Connection of upright structural members to top of arch member on east side of north end of bridge. Oblique detail view southwest (from beside bridge). 360 mm lens. - Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, Nevada County, CA

  17. DETAIL OF THE UNDERSIDE OF THE BRIDGE, ABUTMENT, AND WING ...

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

    DETAIL OF THE UNDERSIDE OF THE BRIDGE, ABUTMENT, AND WING WALL ON THE EAST SIDE OF THE NORTH END OF THE BRIDGE. 38 - Burlington Northern Santa Fe Railroad, Cajon Subdivision, Structure No. 61.5X, between Cajon Summit and Keenbrook, Devore, San Bernardino County, CA

  18. VIEW TO THE NORTH TOWARD THE WING WALL AND CONCRETESLAB ...

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

    VIEW TO THE NORTH TOWARD THE WING WALL AND CONCRETE-SLAB CHANNEL WALL ON THE WEST SIDE OF THE NORTH END OF THE BRIDGE. NOTE THE SMALL CULVERT OPENING BEHIND SAGEBRUSH NEAR THE END OF THE WING WALL. 37 - Burlington Northern Santa Fe Railroad, Cajon Subdivision, Structure No. 61.5X, between Cajon Summit and Keenbrook, Devore, San Bernardino County, CA

  19. Hydrothermal remobilisation around a deformed and remobilised komatiite-hosted Ni-Cu-(PGE) deposit, Sarah's Find, Agnew Wiluna greenstone belt, Yilgarn Craton, Western Australia

    NASA Astrophysics Data System (ADS)

    Le Vaillant, Margaux; Saleem, Ahmad; Barnes, Stephen J.; Fiorentini, Marco L.; Miller, John; Beresford, Steve; Perring, Caroline

    2016-03-01

    The Sarah's Find nickel deposit, located 4.5 km north of the Mount Keith nickel mine, Western Australia, was chosen as a case study to investigate the nature and three-dimensional geometry of a geochemical halo created by the hydrothermal remobilisation of base metals and platinum group elements into the country rock surrounding a small massive Ni sulphide orebody. Portable and laboratory-based XRF analyses were carried out on samples from a shear zone localised along the basal komatiite-dacite contact that hosts the orebody. A geochemical halo was identified that extends along the shear zone up to 1780 m away from the massive sulphides, parallel to a prominent stretching lineation. Elevated Ni and Pd are associated with high As, Co, Cu and S. Palladium and Pt concentrations increase with proximity to massive sulphides (from 6 to 1190 ppb Pd). These anomalous concentrations reflect the presence of sulfarsenides and sulphides, either physically remobilised and forming veinlets close to the massive sulphides, or hydrothermally transported and redeposited within the foliation. In situ laser ablation ICP-MS indicates that Pd and Pt are hosted within these nickel sulfarsenides. This Ni-Co-As-Pd geochemical halo, observed around the Sarah's Find ore body, is interpreted as forming syn deformation, by the circulation of As-rich hydrothermal fluids dissolving base metals, Pd and Pt from the orebody and redepositing them along the sheared footwall contact. Similar Ni-Co-Pd-Pt-As geochemical haloes could potentially exist around any magmatic nickel sulphide mineral system that has undergone a phase of arsenic metasomatism and may be a generally applicable proximity indicator for nickel sulphides in hydrothermally altered terranes.

  20. Dal'negosrk skarn deposit, Sikhote-Alin: Stages and sources of matter for borosilicate ores

    NASA Astrophysics Data System (ADS)

    Karas', O. A.; Ratkin, V. V.

    2014-04-01

    The danburite orebody at the northeastern wall of the open pit of the Dal'negorsk borosilicate deposit is studied. The comparative mineralogical-, isotopic-, and thermobarogeochemical analyses of danburite from the Levoberezhnyi area and datolite of the late skarn stage from the Tsentral'nyi open pit confirms that danburite is a result of the early borosilicate stage of formation of the deposit. Combined with previously published data, it is concluded that marine sedimentary rocks or Early Cretaceous arkose sandstones from the matrix of the Taukhin accretionary prism could be the source of boron.

  1. Magmatic conduit melt-fluid metallogenic system- A new Genetic Model for Xishimen Iron Deposit, Wuan area, Hebei province, China

    NASA Astrophysics Data System (ADS)

    SU, S.; Hou, J.; Luo, Z.; Cui, Y.; Yang, Y.

    2015-12-01

    Xishimen Iron deposit is located in Wuan city, Hebei province, China. it is a typical skarn deposit, but some geological characteristics in the deposit cannot been explained by skarn model. We will try to reveal the genetic mechanism of the iron deposit¢s in this paper. Orebodys mainly occur along the boundary of diorite and metalimestone in the Xishimen iron deposit. Some orebodys intruded into diorites or limestones. There are vesicles in some massive ores. Magnetite from the lower part of orebody occur between diopside and tremolite as an intersititial minerals. Magnetites from upper part of the orebody are eqilibrium with calcite, apatite, Talc, pyrite and chalcopyrite. Magnetites coexisting with dioposide, tremolite and phlogopite have more than 15000 ppm TiO2, and riched in SiO2. However, magnetites coexisting with calcite, talc and sulfides have 200 ppm- 400 ppm TiO2, and poored in SiO2. Magnetites coexisting with talc have highest Al2O3, MgO, and MnO. Magnetites coexisting with calcite and sulfide have lowest Al2O3, MnO and MgO. Trace element analysis results of magnetite show that magnetite coexisting with dioposide, tremolite and phlogopite are riched in Ti and Ta, and depleted Nb and Y. Magnetite coexisting with calcite, talc and sulfide are usually have poor positive or no anomaly of Ti and Ta, and have poor positive anomaly of Nb, Hf, and Y. The analysis results of Fe isotope for ores and rocks in Xishimen iron deposit show that there is a negative correlation relationship between altitude and the value of Fe isotope. The heavy Fe isotopes of ores are richer in the lower part than in the upper part. The origin processes of Xishimen iron deposit are: (1) mafic-intermediate magma riched in iron reacted with limestone, and make the "iron magma" formation; (2) Fluids are added into the metallogenic system continuously, and "iron magma" was getting less density; (3) "iron magma" bearing fluids uplifting along magma conduit because of fluid superpressure

  2. H-bonding scheme and cation partitioning in axinite: a single-crystal neutron diffraction and Mössbauer spectroscopic study

    NASA Astrophysics Data System (ADS)

    Gatta, G. Diego; Redhammer, Günther J.; Guastoni, Alessandro; Guastella, Giorgio; Meven, Martin; Pavese, Alessandro

    2016-05-01

    The crystal chemistry of a ferroaxinite from Colebrook Hill, Rosebery district, Tasmania, Australia, was investigated by electron microprobe analysis in wavelength-dispersive mode, inductively coupled plasma-atomic emission spectroscopy (ICP-AES), 57Fe Mössbauer spectroscopy and single-crystal neutron diffraction at 293 K. The chemical formula obtained on the basis of the ICP-AES data is the following: ^{X1,X2} {{Ca}}_{4.03} Y ( {{{Mn}}_{0.42} {{Mg}}_{0.23} {{Fe}}^{2 + }_{1.39} } )_{Σ 2.04} ^{Z1,Z2} ( {{{Fe}}^{3 + }_{0.15} {{Al}}_{3.55} {{Ti}}_{0.12} } )_{Σ 3.82} ^{T1,T2,T3,T4} ( {{{Ti}}_{0.03} {{Si}}_{7.97} } )_{Σ 8} ^{T5} {{B}}_{1.96} {{O}}_{30} ( {{OH}} )_{2.18} . The 57Fe Mössbauer spectrum shows unambiguously the occurrence of Fe2+ and Fe3+ in octahedral coordination only, with Fe2+/Fe3+ = 9:1. The neutron structure refinement provides a structure model in general agreement with the previous experimental findings: the tetrahedral T1, T2, T3 and T4 sites are fully occupied by Si, whereas the T5 site is fully occupied by B, with no evidence of Si at the T5, or Al or Fe3+ at the T1- T5 sites. The structural and chemical data of this study suggest that the amount of B in ferroaxinite is that expected from the ideal stoichiometry: 2 a.p.f.u. (for 32 O). The atomic distribution among the X1, X2, Y, Z1 and Z2 sites obtained by neutron structure refinement is in good agreement with that based on the ICP-AES data. For the first time, an unambiguous localization of the H site is obtained, which forms a hydroxyl group with the oxygen atom at the O16 site as donor. The H-bonding scheme in axinite structure is now fully described: the O16- H distance (corrected for riding motion effect) is 0.991(1) Å and an asymmetric bifurcated bonding configuration occurs, with O5 and O13 as acceptors [i.e. with O16··· O5 = 3.096(1) Å, H··· O5 = 2.450(1) Å and O16- H··· O5 = 123.9(1)°; O16··· O13 = 2.777(1) Å, H··· O13 = 1.914(1) Å and O16- H··· O13 = 146

  3. Long-Term Precipitation Database, Reynolds Creek Experimental Watershed, Idaho, United States

    NASA Astrophysics Data System (ADS)

    Hanson, C. L.

    2001-11-01

    An extensive precipitation database has been developed over the past 35 years with the first records starting in January 1962 and going through September 1996 from the Reynolds Creek Experimental Watershed located near the north end of the Owyhee Mountains in southwest Idaho. Precipitation ranges from 236 mm on the lowest elevations at the north end of the watershed to 1123 mm at the southwest corner of the watershed. There are continuous 35 year records available for 12 sites, 20-32 year records available for 8 sites, 10-19 year records available for 25 sites, and 4-9 year records for 8 sites for a total of 53 sites. All of these data have been stored as breakpoint and hourly records in the U.S. Department of Agriculture, Agricultural Research Service, Northwest Watershed Research Center database. These breakpoint and hourly data are available from the anonymous ftp site: ftp.nwrc.ars.usda.gov.

  4. Three-dimensional oxygen isotope imaging of convective fluid flow around the Big Bonanza, Comstock lode mining district, Nevada

    USGS Publications Warehouse

    Criss, R.E.; Singleton, M.J.; Champion, D.E.

    2000-01-01

    Oxygen isotope analyses of propylitized andesites from the Con Virginia and California mines allow construction of a detailed, three-dimensional image of the isotopic surfaces produced by the convective fluid flows that deposited the famous Big Bonanza orebody. On a set of intersecting maps and sections, the δ18O isopleths clearly show the intricate and conformable relationship of the orebody to a deep, ~500 m gyre of meteoric-hydrothermal fluid that circulated along and above the Comstock fault, near the contact of the Davidson Granodiorite. The core of this gyre (δ18O = 0 to 3.8‰) encompasses the bonanza and is almost totally surrounded by rocks having much lower δ18O values (–1.0 to –4.4‰). This deep gyre may represent a convective longitudinal roll superimposed on a large unicellular meteoric-hydrothermal system, producing a complex flow field with both radial and longitudinal components that is consistent with experimentally observed patterns of fluid convection in permeable media.

  5. Mineralogy, textures, and relative age relationships of massive sulfide ore in the West Shasta district, California ( USA).

    USGS Publications Warehouse

    Howe, S.S.

    1985-01-01

    The Devonian massive sulfide orebodies of the West Shasta district in N California are composed primarily of pyrite, with lesser amounts of other sulfide and gangue minerals. Examination of polished thin sections of more than 100 samples from the Mammoth, Shasta King, Early Bird, Balaklala, Keystone, and Iron Mountain mines suggests that mineralization may be divided into 6 paragenetic stages, the last 5 each separated by an episode of deformation: 1) precipitation of fine-grained, locally colloform and framboidal pyrite and sphalerite; 2) deposition of fine-grained arsenopyrite and coarse-grained pyrite; 3) penetration and local replacement of sulfide minerals of stages 1 and 2 along growth zones and fractures by chalcopyrite, sphalerite, galena, tennantite, pyrrhotite, bornite, and idaite; 4) recrystallization and remobilization of existing minerals; 5) deposition of quartz, white mica, chlorite, and calcite; and 6) formation of bornite, digenite, chalcocite, and covellite during supergene enrichment of several orebodies at the Iron Mountain mine. Mineralogic and textural evidence do not support a second major episode of massive sulfide mineralization during the Permian. -from Author

  6. Timing of the formation of the Changba-Lijiagou Pb-Zn ore deposit, Gansu Province, China: Evidence from Rb-Sr isotopic dating of sulfides

    NASA Astrophysics Data System (ADS)

    Hu, Qiaoqing; Wang, Yitian; Mao, Jingwen; Wei, Ran; Liu, Shengyou; Ye, Dejin; Yuan, Qunhu; Dou, Ping

    2015-05-01

    The giant Changba-Lijiagou Pb-Zn deposit is located in the north of the Xihe-Chengxian (abbreviated as "Xicheng") ore cluster in Gansu Province, China. The orebodies in the deposit are mainly hosted in the marble, dolomitic marble, and biotite-calcite-quartz schist of the Middle Devonian Anjiacha Formation. The genesis of the deposit has previously been argued to be of SEDEX type (sedimentary exhalative type) or of epigenetic hydrothermal type. This paper reports results of Rb-Sr isotopic dating on sphalerite and pyrite taken from the main orebody, which yield an isochron age of 222.3 ± 2.2 Ma for eight sphalerite samples, and 222.0 ± 3.0 Ma for the eight sphalerite samples combined with four pyrite samples, indicating that the deposit formed during the Late Triassic. The (87Sr/86Sri) value of the sphalerite is 0.71370 ± 0.00013, and that of the sphalerite and pyrite is 0.71371 ± 0.00014, which are identical within experimental error, suggesting that the ore metals are derived mainly from the continental crust. By integrating the present results with the regional geology, we propose that the Changba-Lijiagou Pb-Zn deposit is a product of regional hydrothermal mineralization processes, forced by tectono-magmatic activities, which took place in the Xicheng ore cluster during Triassic orogenic processes.

  7. Kimberlite emplacement models — The implications for mining projects

    NASA Astrophysics Data System (ADS)

    Jakubec, Jaroslav

    2008-06-01

    The significance of the emplacement model for kimberlite pipes, or sheets, is commonly recognized in resource geology. However, its importance is not always appreciated in the mine design process. The fact is that knowledge of the orebody geometry, character of the contact zones, internal structures, rock mass competency and distribution of inclusions could directly influence the selection of the underground mining method, pit wall stability, dilution, treatability, and the dewatering strategy. The problems are exacerbated in smaller pipes and narrower sheets, and in more irregular shapes; they are more apparent in underground mining as opposed to open cast. Various kimberlite emplacement processes have a major impact on the nature of the kimberlite orebody and host rocks that will influence the mine design and mining strategy. Failure to understand these processes can adversely affect the economic outcome for developing a mine. It is therefore important to investigate those processes in order to better characterize the mining constraints and risks, and more accurately predict the mine's economic viability.

  8. 17. Photocopy of photograph (original copy in Edison collection). Photographer ...

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

    17. Photocopy of photograph (original copy in Edison collection). Photographer and date unknown, although probably taken before 1920. VIEW OF NORTH END OF TULE RIVER POWERHOUSE SHOWING POWERHOUSE AT PHOTO CENTER, TRANSFORMER BUILDING TO RIGHT OF POWERHOUSE, GARAGE TO LEFT OF POWERHOUSE, AND OPERATOR COTTAGE BEHIND POWERHOUSE AND TRANSFORMER HOUSE. VIEW TO SOUTHEAST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA

  9. Reconnaissance Report for Hydropower Redevelopment at Sault Ste. Marie, Michigan.

    DTIC Science & Technology

    1981-01-01

    hydropower facility. The St. Marys River, extending from Whitefish Bay at the east end of Lake Superior to Lake Huron , falls about 22 feet over a...connects the southeast end of Lake Superior with the north end of Lake Huron . The St. Marys River is about 67 miles long and is bordered on one side by...2-Way Channels (Including Anchorage Areas) and Over Westerly 300-Foot Width of Upbound Middle Neebish Channel, When Levels of Lake Superior and Huron

  10. 12. "OBSERVATION POSTS, STRUCTURAL PLANS AND DETAILS." Specifications No. OC25572; ...

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

    12. "OBSERVATION POSTS, STRUCTURAL PLANS AND DETAILS." Specifications No. OC2-55-72; Drawing No. 60-09-12; sheet 89 of 148; file no. 1321/40, Rev. A. Very faint stamp above note reads: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  11. 9. "TEST STAND; STRUCTURAL; CABLE TUNNEL, PLAN, SECTIONS, DETAILS." Specifications ...

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

    9. "TEST STAND; STRUCTURAL; CABLE TUNNEL, PLAN, SECTIONS, DETAILS." Specifications No. OC1-55-72-(Rev.); Drawing No. 60-09-12; sheet 43 of 148; file no. AF 1320/94, Rev. A. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  12. 27. "TEST STAND; STRUCTURAL; SIDEWALL, NORTH WALL AND SOUTH WALL ...

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

    27. "TEST STAND; STRUCTURAL; SIDEWALL, NORTH WALL AND SOUTH WALL FRAMING ELEVATIONS." Specifications No. ENG-04353-55-72; Drawing No. 60-09-12; sheet 27 of 148; file no. 1320/78. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, Rev. B; date: 15 April 1957. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  13. 11. "INSTRUMENTATION AND CONTROL SYSTEMS, EQUIPMENT LOCATION, TEST STAND TERMINAL ...

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

    11. "INSTRUMENTATION AND CONTROL SYSTEMS, EQUIPMENT LOCATION, TEST STAND TERMINAL ROOM, PLANS AND SECTION." Specifications No. ENG-04-353-55-72; Drawing No. 60-0912; sheet 106 of 148; file no. 1321/57. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  14. 10. "ARCHITECTURAL, SECTIONS AND DETAILS." Specifications No. ENG043535572; Drawing No. ...

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

    10. "ARCHITECTURAL, SECTIONS AND DETAILS." Specifications No. ENG-04-353-55-72; Drawing No. 60-09-12; sheet 23 of 148; file no. 1320/74. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  15. 8. "TEST STAND, ARCHITECTURAL, FLOOR PLANS AND SCHEDULES." Specifications No. ...

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

    8. "TEST STAND, ARCHITECTURAL, FLOOR PLANS AND SCHEDULES." Specifications No. ENG-04-353-55-72; Drawing No. 60-0912; sheet 22 of 148; file no. 1320/73. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  16. 26. "TEST STAND, STRUCTURAL, FOUNDATION PLAN." Specifications No. ENG043535572; Drawing ...

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

    26. "TEST STAND, STRUCTURAL, FOUNDATION PLAN." Specifications No. ENG-04-353-55-72; Drawing No. 60-0912; sheet 25 of 148; file no. 1320/76. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  17. 12. "TEST STAND; STRUCTURAL; DEFLECTOR PIT DETAILS, SHEET NO. 1." ...

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

    12. "TEST STAND; STRUCTURAL; DEFLECTOR PIT DETAILS, SHEET NO. 1." Specifications No. ENG-04-353-55-72; Drawing No. 60-09-12; sheet 41 of 148; file no. 1320/92, Rev. A. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  18. Flow Encountering Abrupt Topography

    DTIC Science & Technology

    2013-09-30

    Colin at the Coral Reef Research Foundation and Paul Collins, who has extensive experience with such data). Helen Reef Concerted UCTD measurements...the main islands of Palau and diverts around the south and north ends of the island group (Figure 1, left and right; Section ). At Helen Reef and Toby...are very steep, mapping close to the reef fringe was done during daylight hours. At each of the southern islands, two or three circumnavigations of

  19. Lorain Harbor, Ohio. Preliminary Feasibility Study (Stage 2). Review of Reports. Volume II. Appendices.

    DTIC Science & Technology

    1980-10-01

    this alignment also requires relocation of a major electric transmission line and an oil tank farm on the north end. The alignment downstream fully...lubricating oil is approximately $1,600. Wages complete, including vacation, fringe benefits, etc. is $4,200 per day. The remaining $1,000 per day goes for...LEVEL BRIDGE: It was shown that all feasible alignments would traverse the property of Allied Oil and be restricted by the tanks. A pedistrian walk on

  20. Regional geochemical study of the felsic plutonic rocks in the Nuqrah Quadrangle, sheet 25E, Kingdom of Saudi Arabia

    USGS Publications Warehouse

    Hall, W.E.; Dellinger, David; Selner, G.I.

    1985-01-01

    Pan-concentration samples collected from wadis draining the north end of Jabal Safad contain anomalous Sn, Mo, Pb, and La. Four samples contain 250 to 1,000 ppm of tin. The tin anomaly is associated with a small aplitic pluton intrusive into the Jabal Safad alkalic granite complex. A brief reconnaissance of the area did not reveal any greisen or cassiterite mineralization. However, further exploration work in the area is recommended.

  1. 17. A closeup detail, looking east from the northeast corner ...

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

    17. A close-up detail, looking east from the northeast corner of the roadbed. This image shows the concrete commemorative inscription which is let into the inside of the eastern balustrade at the north end of the bridge. The name of one of the county commissioners has been chiselled out of the inscription. The parting fault between the parapet and its coping is evident. - Vigo County Bridge No. 139, Spanning Sugar Creek at Seventy-fourth Place, Terre Haute, Vigo County, IN

  2. 29. Aerial photograph (1973) looking south across Gould Island. Firing ...

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

    29. Aerial photograph (1973) looking south across Gould Island. Firing pier (still possessing third and fourth levels) in foreground. Pitched roof extending from south end of firing pier marks location of frame approach between pier and shop building (center rear) and power plant (to right of shop). Photo courtesy of Naval Undersea Warfare Center, Division Newport, Rhode Island. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  3. 28. Undated aerial photograph taken prior to removal of third ...

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

    28. Undated aerial photograph taken prior to removal of third and fourth levels of firing pier in the 1980s. View looking northwest shows harbor serving the firing pier, with craft berthed alongside the recovery dock and finger pier. Photo courtesy of Naval Undersea Warfare Center, Division Newport, Rhode Island. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  4. 24. BUILDING NO. 452, ORDNANCE FACILITY (BAG CHARGE FILLING PLANT), ...

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

    24. BUILDING NO. 452, ORDNANCE FACILITY (BAG CHARGE FILLING PLANT), INTERIOR VIEW LOOKING WEST AT NORTH END OF CENTRAL CORRIDOR (ROOM 3). STAIRWAY WORKBENCH WITH COMPRESSED-AIR POWERED CARTRIDGE LOADER. ARMORED PASS-THROUGH OF TRANSFER BOX FOR PASSING EXPLOSIVES MATERIALS THROUGH TO NEXT ROOM TO THE NORTH. - Picatinny Arsenal, 400 Area, Gun Bag Loading District, State Route 15 near I-80, Dover, Morris County, NJ

  5. 119. VIEW OF NORTH SIDE OF LANDLINE INSTRUMENTATION ROOM (206), ...

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

    119. VIEW OF NORTH SIDE OF LANDLINE INSTRUMENTATION ROOM (206), LSB (BLDG. 751). POWER DISTRIBUTION UNITS AND CABLE DISTRIBUTION UNITS ON RIGHT SIDE OF PHOTO; LOGIC CONTROL AND MONITOR UNITS FOR BOOSTER AND FUEL SYSTEMS LEFT OF AND PARALLEL TO EAST ROW OF CABINETS; SIGNAL CONDITIONERS AT NORTH END OF ROOM PERPENDICULAR TO OTHER CABINETS. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  6. Aerial Surveys of Endangered Whales in the Beaufort Sea, Chukchi Sea, and Northern Bering Sea.

    DTIC Science & Technology

    1981-06-01

    of Kivalina. The entire area from this point to the village of Wales was icebound. Figure 3 shows the typical ice conditions of the Bering Sea...area extending across the Bering Straits from Cape Prince of Wales to the north end of Little Diomede Island. Large concentrations of pan ice with a 7...ice conditions across the main area of sightings between Wales and Little Diomede Island throughout the survey effort. 8 !. I. I Beaufort Sea I.Brrow

  7. Acoustic Behavior, Baseline Ecology and Habitat Use of Pelagic Odontocete Species of Concern

    DTIC Science & Technology

    2011-09-30

    measurements: 1) Quantitatively assess the acoustic signals of Hawaiian insular false killer whales (FKWs) and melon-headed whales (MHWs). 2...individual Hawaiian insular false killer and melon-headed whales . This project will be conducted over four, 2-week tagging periods spread between three...successfully deployed there on both FKWs and MHWs. The north end of the island is a high use area for Hawaiian insular false killer whales (Baird et al

  8. 27. INTERIOR VIEW TO THE WEST OF ROOM 126 AT ...

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

    27. INTERIOR VIEW TO THE WEST OF ROOM 126 AT THE NORTH END OF THE ENTRANCE HALLWAY TO THE POST-MORTEM CELLS. IN THE CEILING IS A HATCHWAY TO THE UPPER LEVEL OF ROOM 123, THE DISASSEMBLY BAY, BY WHICH PARTS OF THE NUCLEAR REACTOR WERE PASSED FOR FURTHER DISASSEMBLY IN THE VARIOUS POST-MORTEM CELLS. - Nevada Test Site, Reactor Maintenance Assembly & Dissassembly Facility, Area 25, Jackass Flats, Junction of Roads F & G, Mercury, Nye County, NV

  9. 1. TEST STAND 1A ENVIRONS, SHOWING WEST SIDE OF TEST ...

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

    1. TEST STAND 1-A ENVIRONS, SHOWING WEST SIDE OF TEST STAND 1-A, RP1 COMBINED FUEL STORAGE TANK FARM BELOW WATER TANKS ON HILLSIDE TO LEFT, AND TEST STAND 1-B IN DISTANCE AT RIGHT. Looking east. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  10. 25. "TEST STAND 1A UTILIZED TO TEST THE ATLAS ICBM", ...

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

    25. "TEST STAND 1-A UTILIZED TO TEST THE ATLAS ICBM", CROPPED OUT: "DIRECTORATE OF MISSILE CAPTIVE TEST, EDWARDS AFB." Photo no. 11,371 57; G-AFFTC 15 OCT 57. Looking southwest from below the stand. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  11. 23. "A CAPTIVE ATLAS MISSILE EXPLODED DURING THE TEST ON ...

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

    23. "A CAPTIVE ATLAS MISSILE EXPLODED DURING THE TEST ON TEST STAND 1-A, 27 MARCH 1959, PUTTING THAT TEST STAND OUT-OF-COMMISSION. STAND WAS NOT REPAIRED FOR THE ATLAS PROGRAM BUT TRANSFERRED TO ROCKETDYNE AND MODIFIED FOR THE F-l ENGINE PROGRAM." - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  12. 22. INTERIOR VIEW OF THE MACHINE SHOP LOOKING NORTH. FROM ...

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

    22. INTERIOR VIEW OF THE MACHINE SHOP LOOKING NORTH. FROM LEFT TO RIGHT, NORTH END OF THE LONG LATHE, WOOD STOVE WITH A BRICK HEARTH FLOOR, FAR BACK LEFT CORNER IS THE MAIN CLUTCH FOR THE MILL POWER SHAFTS, SHAFT LATHE, SMALL PLANER, BORING MACHINE WITH IONIC COLUMN DETAIL., AND THE ENTRANCE TO THE ELECTRICAL MOTOR ROOM. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

  13. 27. Bollinger twinchain tandem, pigcasting machine, located at the north ...

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

    27. Bollinger twin-chain tandem, pig-casting machine, located at the north end of the plant. Prior to closing, approximately 40 percent of the plant's: iron production was cast into pigs and sold to foundry customers. The pig-casting machine employed a controller, lime man, trough man, and crane operator. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

  14. 25. Photographic copy of ink on linen drawing (at the ...

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

    25. Photographic copy of ink on linen drawing (at the archives of Niagara Mohawk Power Corporation, 300 Eric Boulevard West, Syracuse, New York 13202), Strand, Draftsman, July 3, 1913. Sheet 1-260, Finch, Pruyn & Company and International Paper Company. Detail of concrete dam and headgate wall. Detail showing profile of the north end of headgate wall. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

  15. Cape Cod Easterly Shore Beach Erosion Study. Volume 2

    DTIC Science & Technology

    1979-04-01

    north end of Marconi Beach was the location of Guglielmo Marconi’s perma- nent wireless radio station that established contact with Cornwall, England...abandoned rjlacial stream valleys such as Blackfish Creek near the Marconi Station and the Pamet River Valley in Truro also slope to the west. In the...traffic. Foot traffic, however, causes a problem in all areas. Figure 1-A17 shows where foot traffic has worn paths into the dunes and cliffs at Marconi

  16. Test Plan for the Large-Scale Operations Management Test of Insects and Pathogens for Control of Water Hyacinth in Louisiana.

    DTIC Science & Technology

    1979-06-01

    north end of Lake Concordia in Concordia Parish, Louisiana, and filled with waterhyacinth plants col- lected from the population that grows naturally on... naturally occurring Arzama as a control agent for waterhyacinth lies in its temporary or seasonal effects on large plants . Research on procedures for...identify by block numiber) Aquatic plant control Waterhyacinths Insects Management methods Pathogens ft AWACT (Cmaonmo ee ebbMs san Ilmend identify by block

  17. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the locations set out in the table to this section. Table 1. South Shore Canal: (a) Turning Basin No... vessels up to 80 m in overall length. (1) North end of Wharf No. 1, (2) Tie-up wall above Lock 1, (3) Tie-up wall below Lock 2, (4) Wharf No. 9, (5) Between the southerly extremities of Wharves 18-2 and...

  18. Radiological Survey and Remediation Report DRMO Yard

    DTIC Science & Technology

    1996-11-01

    as "affected" areas as defined by NUREG /CR-5849 Manual for Conducting Radiological Surveys in Support of License Termination, (NRC, 1992): The tire...requiring survey as defined by NUREG /CR-5849, due to the uncertainty of the boundary where crushing was performed in the north end of the yard. i The...identified the following areas as "affected" areas as defined by NUREG /CR-5849 Manual for Conducting Radiological Surveys in Support of I License

  19. Alteration, oxygen isotope, and fluid inclusion study of the Meishan iron oxide-apatite deposit, SE China

    NASA Astrophysics Data System (ADS)

    Yu, Jinjie; Che, Linrui; Wang, Tiezhu

    2015-10-01

    The Meishan deposit (338 Mt at 39 % Fe) comprises massive ores in the main orebody and stockwork and disseminated ores along the main orebody. Four stages of mineralization and related alteration have been identified. The second stage of mineralization, which was the main stage of iron mineralization, formed stringer, disseminated iron ores, as well as the main Meishan orebody. The fourth stage formed small pyrite and/or gold orebodies above or alongside the main magnetite orebody. Stage 2 apatites have homogenization temperatures of 257-485 °C and salinities of 7.3-11 wt% NaCleq. Calculated δ18Ofluid values of magnetite and apatite from the disseminated ores vary between 7.7 and 14.9 ‰, which is similar to values observed in the massive ores (8.1-12.9 ‰). The high-18O fluids at Meishan have been interpreted as being of magmatic-hydrothermal origin. These fluids are indicative of the boiling of ore-forming fluids. Quartz, occurring as cavity fillings, gives homogenization temperatures from 202 to 344 °C, with most values lying between 250 and 330 °C. Corresponding salinities are ˜5 wt% NaCleq. Calculated δ18Ofluid values are +6.4 to +6.8 ‰. These values indicate that the lower-temperature (250-330 °C) quartz was deposited from a cooling magmatic-hydrothermal fluid. Stage 3 siderites contain fluid inclusions that homogenized between 190 and 310 °C, mainly between 210 and 290 °C. Corresponding salinities are 4-8 wt% NaCleq. Stage 4 quartz-carbonate veinlets contain fluid inclusions that homogenized at moderate to low temperatures (150-230 °C) and exhibit low salinities (2-10 wt% NaCl eq). δ18Ofluid values of the mineralizing fluids for the quartz and calcite can be calculated to vary from -0.7 to +5.6 ‰ and +6.3 to +10.2 ‰, respectively. While there is some overlap, the δ18O values of the fluids are generally lower than those observed in the massive and disseminated magnetite ores. δD values for the quartz and calcite vary between -154 and -123

  20. Fluid inclusion and noble gas studies of the Dongping gold deposit, Hebei Province, China: A mantle connection for mineralization?

    USGS Publications Warehouse

    Mao, J.; Li, Y.; Goldfarb, R.; He, Y.; Zaw, K.

    2003-01-01

    The Dongping gold deposit (>100 t Au) occurs about 200 km inboard of the northern margin of the North China craton. The deposit is mainly hosted by syenite of a middle Paleozoic alkalic intrusive complex that was emplaced into Late Archean basement rocks. Both groups of rocks are intruded by Late Jurassic to Early Cretaceous crustal-melt granite dikes and stocks, some within a few kilometers of the deposit. The gold ores were deposited during this latter magmatic period at about 150 Ma, a time that was characterized by widespread regional north-south compression that formed the east-west-trending Yanshan deformational belt. The ores include both the telluride mineral-bearing, low sulfide quartz veins and the highly K-feldspar-altered syenite, with most of the resource concentrated in two orebodies (1 and 70). Fluid inclusion microthermometry indicates heterogeneous trapping of low-salinity (e.g., 5-7 wt % NaCl equiv) fluids that varied from a few to 60 mole percent nonaqueous volatile species. Laser Raman spectroscopy confirms that the vapor phase in these inclusions is dominated by CO2, but may be comprised of as much as 9 mole percent H2S and 20 mole percent N2; methane concentrations in the vapor phase are consistently <1 mole percent. The variable phase ratios are consistent with fluid immiscibility during ore formation. Fluid inclusion trapping conditions are estimated to be 250?? to 375??C and 0.6 to 1.0 kbar. Helium isotope studies of fluid inclusions in ore-stage pyrites indicate He/He ratios of 2.1 to 5.2 Ra (Ra = 1.4 x 10-6 for air) for orebody 1 and 0.3 to 0.8 Ra for orebody 70. The former data suggest that at least 26 to 65 percent mantle helium occurs in the fluids that deposited the veins in orebody 1. The lower values for orebody 70, which is characterized by a more disseminated style of gold mineralization, are interpreted to reflect an increased interaction of ore fluids with surrounding crustal rocks, which may have contributed additional He to

  1. Full Scale Wind Tunnel and Seaplane Tow Channel

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Construction progress, Full Scale exit cone looking south from entrance cone, east switchboard, west switchboard, wind vanes at north end looking north through entrance cone, north end looking south through entrance cone, entrance cone looking north from exit cone, wind vanes south end of west exit cone, wind vanes south end of east exit cone, Tow Channel trolley lines looking north, east and west incline braces at north end. Full-Scale Tunnel (FST) exit cone construction and installation of fan motors. Smith DeFrance describes the entrance cone in NACA TR 459 as follows: 'Forward of the propellers and located on the center line of the tunnel is a smooth fairing which transforms the somewhat elliptic section of the single passage into two circular ones at the propellers. From the propellers aft, the exit cone is divided into two passages and each transforms in the length of 132 feet from a 35-foot 61/2-inch circular section to a 46-foot square. The included angle between the sides of each passage is 6 inches.' (p. 293)

  2. A proactive approach to sustainable management of mine tailings

    NASA Astrophysics Data System (ADS)

    Edraki, Mansour; Baumgartl, Thomas

    2015-04-01

    The reactive strategies to manage mine tailings i.e. containment of slurries of tailings in tailings storage facilities (TSF's) and remediation of tailings solids or tailings seepage water after the decommissioning of those facilities, can be technically inefficient to eliminate environmental risks (e.g. prevent dispersion of contaminants and catastrophic dam wall failures), pose a long term economic burden for companies, governments and society after mine closure, and often fail to meet community expectations. Most preventive environmental management practices promote proactive integrated approaches to waste management whereby the source of environmental issues are identified to help make a more informed decisions. They often use life cycle assessment to find the "hot spots" of environmental burdens. This kind of approach is often based on generic data and has rarely been used for tailings. Besides, life cycle assessments are less useful for designing operations or simulating changes in the process and consequent environmental outcomes. It is evident that an integrated approach for tailings research linked to better processing options is needed. A literature review revealed that there are only few examples of integrated approaches. The aim of this project is to develop new tailings management models by streamlining orebody characterization, process optimization and rehabilitation. The approach is based on continuous fingerprinting of geochemical processes from orebody to tailings storage facility, and benchmark the success of such proactive initiatives by evidence of no impacts and no future projected impacts on receiving environments. We present an approach for developing such a framework and preliminary results from a case study where combined grinding and flotation models developed using geometallurgical data from the orebody were constructed to predict the properties of tailings produced under various processing scenarios. The modelling scenarios based on the

  3. Discontinuum Modelling Approach for Stress Analysis at a Seismic Source: Case Study

    NASA Astrophysics Data System (ADS)

    Sainoki, Atsushi; Mitri, Hani S.; Yao, Mike; Chinnasane, Damodara

    2016-12-01

    Rockbursts in underground mines can cause devastating damage to mine workings; hence, it is important to be able to assess the potential for their occurrence. The present study focuses on a large seismic event that took place at an underground base metal mine in Canada. The event took place in a dyke near the 100/900 orebodies on 3880 Level (1180 m below surface) of the Copper Cliff Mine in Sudbury, Canada. A 3D continuum stress analysis of the orebodies, i.e., 100 and 900, using an orebody-wide model encompassing the major geological structures and in situ stress heterogeneity in the mine shows low potential for rockburst at the seismic source location—a result which contradicts the fact that a large seismic event actually took place. A postulation is thus made that there had been highly stressed regions caused by geological disturbances at the source location before mining activities took place. In order to verify the postulation, a further study is undertaken with the discrete element modelling technique, whereby a cube-shaped model containing a fracture network is subjected to a stress state similar to that at the source location. A model parametrical study is conducted with respect to the distribution of the fracture (joint) network and its mechanical properties. The results reveal that when joints are densely distributed at the source location, the stress state becomes significantly burst prone. It is observed that the length, density, stiffness, and orientation of joints have a large influence on the stress state along the joints, while the friction angle, cohesion, and tensile strength do not influence the stress state. A cube-shaped model is constructed with joint sets actually mapped at the mine and a stress analysis is performed. The results demonstrate the generation of highly stressed regions due to the interaction of the joints with the applied in situ stress fields, thus leading to burst-prone conditions. The present study numerically confirms that

  4. Geologic studies in the Sierra de Pena Blanca, Chihuahua, Mexico

    NASA Astrophysics Data System (ADS)

    Reyes-Cortes, Ignacio Alfonso

    grade of the rock units; and the possible paths of potential leachate through the geologic media. The last part of the work relates to the natural analog of the Yucca Mountain, the Nopal I orebody, which is compared and found similar in its geologic frame work, in the lithologic units and their weathering, in the stratigraphic relationships with the vitrophyres and tuff horizons, in the climatic dryness, in the regional water table depth and the hydrologic features, in the ignimbritic units mineralogy, and in the radioactive waste fuel compared to the ore mineralogy of the Nopal I. There are mineralogic determinations of the fracture fill material in the orebody and host rock; detailed mapping of the fractures and surface alterations; and gamma ray grid measurements and electromagnetic soundings. All these studies indicate a support criteria to take the Nopal I as a natural analogue of the Yucca Mountain repository. The total evolution of the Nopal I orebody is exposed in the walls and floors of the +00 and +10 levels, which are ready to perform final safety tests in order to compare it with the future Yucca Mountain repository behavior. The Nopal in orebody has been there for several hundred of thousands and may be millions of years in an natural equilibrium with the surrounding environment. (Abstract shortened by UMI.)

  5. Origin of coffinite in sedimentary rocks by a sequential adsorption-reduction mechanism.

    USGS Publications Warehouse

    Goldhaber, M.B.; Hemingway, B.S.; Mohagheghi, A.; Reynolds, R.L.; Northrop, H.R.

    1987-01-01

    Coffinite is the dominant ore mineral in the V-U ores of the Tony-M mine in the Henry Mts mineral belt of the Colorado Plateau. This orebody was formed at a density-stratified solution interface between uranyl-ion-bearing meteoric water and a saline fluid which was locally reducing. The localization of U at this solution interface occurred by adsorption onto the surfaces of detrital minerals, this adsorption being related to the pH difference between the two fluids. Experimental evidence is presented showing that the adsorption facilitated the reduction of uranium to U(IV). This adsorbed, reduced uranium bonded with aqueous silica in the ore zone to form coffinite. The high concentration of silica (as a monomeric species) in the ore-forming solution stabilized coffinite in preference to uraninite.-R.A.H.

  6. Epigenetic lead, zinc, silver, antimony, tin, and gold veins in Boulder Basin, Blaine and Custer counties, Idaho; potential for economic tin mineralization

    USGS Publications Warehouse

    Ratchford, Michael E.

    2002-01-01

    Boulder Basin is in a northwest-trending belt of allochthonous Paleozoic rocks in the Boulder Mountains of central Idaho. Regional Tertiary extension resulted in widespread normal faulting and coeval emplacement of shallow-level intrusions and extrusive rocks of the Challis Volcanic Group. Epigenetic lead-zinc-silver-antimony-tin-gold vein deposits formed during Tertiary extension and are hosted within Paleozoic strata. The major orebodies are in the lower plate of the Boulder Basin thrust fault, in massive quartzite of the Middle Pennsylvanian to Lower Permian Wood River Formation. Anomalous concentrations of tin are present in the base-metal mineral assemblage of the Boulder Basin ore deposits. The tin-bearing veins in Boulder Basin are strikingly similar to Bolivian tin deposits. The deposit model for Bolivian tin deposits identifies buried tin porphyry below the tin-bearing vein system.

  7. Geologic controls of uranium mineralization in the Tallahassee Creek uranium district, Fremont County, Colorado.

    USGS Publications Warehouse

    Dickinson, K.A.

    1981-01-01

    Two important orebodies have been defined by drilling in the Tallahassee Creek uranium district, Fremont County, Colorado, namely the Hansen and the Picnic Tree. Host rocks are respectively the upper Eocene Echo park Alluvium, and the lower Oligocene Tallahassee Creek Conglomerate. Average ore grade is about 0.08% U3O8. The principal source rock is the lower Oligocene Wall Mountain Tuff. Leaching and transportation of the uranium occurred in alkaline oxidizing ground water that developed during alteration of the ash in a semi-arid environment. The uranium was transported in the groundwater and deposited in a reducing environment controlled by carbonaceous material and associated pyrite. Localization of the ore was controlled by groundwater flow conditions and by the distribution of organic matter in the host rock. -from Author

  8. The Relief Canyon gold deposit, Nevada: a mineralized solution breccia

    USGS Publications Warehouse

    Wallace, A.R.

    1989-01-01

    The Relief Canyon gold deposit in the Humboldt Range of western Nevada is a low-grade, high-tonnage orebody of Tertiary or younger age. The host rocks include limestones of the Triassic Cane Spring Formation, which are overlain by shales of the Triassic Grass Valley Formation. Gold, fluorite, pyrite, silver, calcite, and fine-grained silica are the principal hydrothermal minerals in the deposit. The deposit formed at a relatively shallow depth. On the basis of fluid inclusion data, late-stage hydrothermal fluids related to gold and fluorite deposition were extremely dilute and had temperatures near 200??C. The fluid inclusions in fluorite show no evidence for boiling, but porous crackle breccias in the jasperoids suggest that hydrobrecciation took place. -from Author

  9. Sulphur isotope geochemistry of the ores and country rocks at the Almadén mercury deposit, Ciudad Real, Spain

    NASA Astrophysics Data System (ADS)

    Saupé, Francis; Arnold, Michel

    1992-10-01

    Seventy-four new S isotope analyses of ore minerals and country rocks are given for the Hg deposit of Almadén. The spread of the cinnabar δ34S is narrow within each of the three orebodies, but the δ34S average values differ sufficiently between them (mean δ34S: San Nicolas = 0.2 ± 1.1 %., San Francisco = 8.1 ± 0.7%., San Pedro = 5.9 ± 1.0%.) to indicate three different mineralization episodes and possibly processes. The unweighted mean for all cinnabar samples is 5.6%. and the S source is considered to be the host-rocks, either the Footwall Shales ( δ34S = 5.5%.) or the spilites ( δ34 S = 5.1 ± 1.3%.). For geometric and chronologic reasons, the former seem the best potential source. However, the high δ34 S values of the San Francisco cinnabar cannot be explained without addition of heavy S from reduction of seawater sulphate. Orderly distributions of the δ34S values are observed in all three orebodies: (1) their increase from the stratigraphic bottom to the top in the San Pedro orebody is explained by a Rayleigh process, and (2) the maxima in the centres of the San Francisco and San Nicolas orebodies are explained by mixing of the S transporting hydrothermal fluids with seawater within the sediments. Associated pyrite and cinnabar were deposited under isotopic disequilibrium, probably because the low solubility of cinnabar caused rapid precipitation of cinnabar. The different morphological pyrite types have their own isotopic δ34S signatures. The spilites are notably enriched in S ( n = 3; average S content = 0.56%) compared to normal basalts (1000 ppm) and have an average δ34S = 5.1 ± 1.3%.. The linear relationship between the δ34S and the S content of the spilites is interpreted as a mixing line between mantle S and a constant S source, probably an infinite open reservoir. An incomplete basalt-seawater reaction at nearly constant temperature is the best explanation for this relation. The S (predominantly pyrite) of the black shales ( n = 3; δ34S

  10. Diagnosis of environmental problems related to vein gold mining in Colombia

    NASA Astrophysics Data System (ADS)

    Prieto, Gloria R.; Gonzalez, Myriam L.

    Since 1985 the annual gold production in Colombia has been fluctuating between 30 and 35 tons (1-1.4 million ounces troy). Exploitation plants can be found in vein and placer gold deposits. During 1992 a preliminary study was undertaken, resulting in a diagnosis of problems in small scale mining in 6 gold areas (vein type) of Colombia. In order to evaluate the general impact caused to the environment due to mining activities, six gold districts located in Nariño, Antioquia, Bolivar, Valle and Caldas Departments were visited. Geochemical analysis (ES, AAS, HGAAS, GFAAS) of orebodies, tailings and waters were carried out, with results that showed high levels of heavy metals in the environmental compartments studied.

  11. Localization of mineralization, its age, and relationship to magmatism at the Mogot silver-base-metal deposit, North Stanovoi metallogenic zone in the southeastern framework of the North Asian Craton

    NASA Astrophysics Data System (ADS)

    Buchko, I. V.; Buchko, Ir. V.; Sorokin, A. A.; Ponomarchuk, V. A.; Travin, A. V.

    2014-03-01

    The results of studying the Mogot silver-base-metal deposit located in the Dzhugdzhur-Stanovoi Superterrane are discussed in this paper. The main ore-controlling structural elements of the studied district are near-latitudinal and NE-trending faults, which are accompanied by zones of hydrothermal metasomatic potassic, propylitic, and argillic alterations, breccias with quartz and quartz-carbonate cement replacing metamorphic rocks and granitoids of the Late Stanovoi Complex. The total sulfide content in ore is 2-3%. The high Ag, Pb, and Zn contents in ore allow us to consider the Mogot deposit as silver-base-metal, since except of orebody 4, there are no silver minerals proper. This indicates that silver is incorporated into crystalline lattice of sulfides. The results of 40Ar/39Ar geochronological investigations show that the hydrothermal ore deposition dated at 127-125 Ma was related to emplacement of intrusions pertaining to the Tynda-Bakaran Complex.

  12. Fluid dynamics, particulate segregation, chemical processes, and natural ore analog discussions that relate to the potential for criticality in Hanford tanks

    SciTech Connect

    Barney, G.S.

    1996-09-27

    This report presents an in-depth review of the potential for nuclear criticality to occur in Hanford defense waste tanks during past, current and future safe storage and maintenance operations. The report also briefly discusses the potential impacts of proposed retrieval activities, although retrieval was not a main focus of scope. After thorough review of fluid dynamic aspects that focus on particle segregation, chemical aspects that focus on solubility and adsorption processes that might concentrate plutonium and/or separate plutonium from the neutron absorbers in the tank waste, and ore-body formation and mining operations, the interdisciplinary team has come to the conclusion that there is negligible risk of nuclear critically under existing storage conditions in Hanford site underground waste storage tanks. Further, for the accident scenarios considered an accidental criticality is incredible.

  13. Bioaccessibility of lead in urban soil of Broken Hill, Australia: A study based on in vitro digestion and the IEUBK model.

    PubMed

    Yang, Kai; Cattle, Stephen R

    2015-12-15

    This study was conducted to investigate lead (Pb) bioaccessibility in urban soil and to assess health risk to children in the city of Broken Hill, Australia, which was established around one of the world's largest lead-zinc-silver mines. Fifty-three topsoil (0-0.1m) and 50 subsoil (0.3-0.5m) samples were collected from earthen footpaths, nature strips, parks or vacant land throughout the urban area. The soil samples were analysed for total Pb concentration, Pb bioaccessibility and Pb mineral phases, together with important soil physicochemical properties known to influence Pb bioaccessibility. Lead bioaccessibility ranged from 24% to 89% in topsoil and from 16% to 100% in subsoil, exhibiting a generally decreasing pattern with increasing distance from the orebody. Lead bioaccessibility was strongly positively related to total Pb concentration in both the topsoil and subsoil. In subsoil, a moderate negative correlation existed between Pb bioaccessibility and soil pH, while a moderate positive correlation existed between Pb bioaccessibility and soil organic matter (OM) content. In contrast, only a weak positive correlation existed between Pb bioaccessibility and OM content in topsoil. The presence of different Pb mineral phases also appeared to have caused variation in soil Pb bioaccessibility, with galena (PbS)-rich samples tending to exhibit lower Pb bioaccessibility. The prediction of blood lead (PbB) levels in Broken Hill children aged 1-4years using the IEUBK model well matched the measured data from a recent PbB screening, suggesting a high risk of childhood chronic low-level Pb exposure (PbB levels >5μg/dL) in Broken Hill, especially in the vicinity of the orebody. Future Pb abatement programs in Broken Hill should utilise the IEUBK model to establish target soil Pb values in an effort to achieve particular child PbB outcomes.

  14. [Study on Mineralogical Characteristics of Quartz and Calcite from Feieling Skarn-Type Pb-Zn Deposit in Southwest Margin of Yunkai Massif].

    PubMed

    Zeng, Chang-yu; Zhao, Ming-zhen; Li, Hong-zhong; Niu, Jia; Zhang, Jie-tang; He, Jun-guo; Zhou, Yong-zhang; Yang, Zhi-jun

    2015-09-01

    The Feieling Pb-Zn deposit of skarn-type is located the in Southwest margin of Yunkai massif, China. This ore deposit can be divided into wall rock near ore, concealed rock mass, endoskarn, exoskarn and orebody. The Raman and FTIR spectrum are conducted to study the mineralogical characteristics of quartz and calcite from five types of rocks from Feieling skarn-type deposit. The analysis shows that the quartz included in the near ore wall rock, endoskarn and exoskarn, comparing with recrystallized quartz of concealed rock mass, has a tend to change into low symmetry quartz in varying degrees. The crystalinity and order degree of quartz from near ore wall rock to concealed rock mass and to endoskarn are becoming higher, but that of quartz from different exoskarn samples display no regular. The origin or the quartz microstructure changes may be related to the multi-stage evolution of skarn mineralization process. The quartz, included in near ore wall rock, endoskarn and exoskarn, become easier to recrystallize and adjust microstructure under the influence of the multi-stage hydrothermal and temperature effect. In anyone sample, the earlier crystalline calcite, showing subhedral-euhedral crystal, display higher crystalinity and order degree. On the contrary, the later crystalline calcite, showing xenomorphic crystal, display lower crystalinity and order degree. Calcite crystal of exoskarn rock contains some silica impurity, while endoskarn and orebody rock is pure. The purity of calcite crystal may relate to Multi-stage evolution of skarn mineralization process. At the early and late skarn stage, active silica-containing fluid is easier to join into calcite, which is under higher temperature environments. On the contrary, at the late quartz-surfide stage, the later crystalized calcite displays higher purity, which is under lower temperature environments. Therefore, spectral characteristics of quartz and calcite reflect multi-stage evolution of skarn mineralization

  15. Lithostratigraphic position and petrographic characteristics of R.A.T. (“Roches Argilo-Talqueuses”) Subgroup, Neoproterozoic Katangan Belt (Congo)

    NASA Astrophysics Data System (ADS)

    Cailteux, J. L. H.; Kampunzu, A. B. H.; Batumike, M. J.

    2005-07-01

    The Neoproterozoic Katangan R.A.T. ("Roches Argilo-Talqueuses") Subgroup is a sedimentary sequence composed of red massive to irregularly bedded terrigenous-dolomitic rocks occurring at the base of the Katangan succession in Congo. Red R.A.T. is rarely exposed in a continuous section because it was affected by a major layer-parallel décollement during the Lufilian thrusting. However, in a number of thrust sheets, Red R.A.T. is in conformable sedimentary contact with Grey R.A.T which forms the base of the Mines Subgroup. Apart from the colour difference reflecting distinct depositional redox conditions, lithological, petrographical and geochemical features of Red and Grey R.A.T. are similar. A continuous sedimentary transition between these two lithological units is shown by the occurrence of variegated to yellowish R.A.T. The D. Strat. "Dolomies Stratifiées" formation of the Mines Subgroup conformably overlies the Grey R.A.T. In addition, a transitional gradation between Grey R.A.T. and D. Strat. occurs in most Cu-Co mines in Katanga and is marked by interbedding of Grey R.A.T.-type and D. Strat.-type layers or by a progressive petrographic and lithologic transition from R.A.T. to D. Strat. Thus, there is an unquestionable sedimentary transition between Grey R.A.T. and D. Strat. and between Grey R.A.T. and Red R.A.T. The R.A.T. Subgroup stratigraphically underlies the Mines Subgroup and therefore R.A.T. cannot be comprised of syn-orogenic sediments deposited upon the Kundelungu (formerly "Upper Kundelungu") Group as suggested by Wendorff (2000). As a consequence, the Grey R.A.T. Cu-Co mineralisation definitely is part of the Mines Subgroup Lower Orebody, and does not represent a distinct generation of stratiform Cu-Co sulphide mineralisation younger than the Roan orebodies.

  16. A precise 232Th-208Pb chronology of fine-grained monazite: Age of the Bayan Obo REE-Fe-Nb ore deposit, China

    USGS Publications Warehouse

    Wang, Jingyuan; Tatsumoto, M.; Li, X.; Premo, W.R.; Chao, E.C.T.

    1994-01-01

    We have obtained precise Th-Pb internal isochron ages on monazite and bastnaesite for the world's largest known rare earth elements (REE)-Fe-Nb ore deposit, the Bayan Obo of Inner Mongolia, China. The monazite samples, collected from the carbonate-hosted ore zone, contain extremely small amounts of uranium (less than 10 ppm) but up to 0.7% ThO2. Previous estimates of the age of mineralization ranged from 1.8 to 0.255 Ga. Magnetic fractions of monazite and bastnaesite samples (<60-??m size) showed large ranges in 232Th 204Pb values (900-400,000) and provided precise Th-Pb internal isochron ages for paragenetic monazite mineralization ranging from 555 to 398 Ma within a few percent error (0.8% for two samples). These results are the first indication that REE mineralization within the giant Bayan Obo ore deposit occurred over a long period of time. The initial lead isotopic compositions (low 206Pb 204Pb and high 208Pb 204Pb) and large negative ??{lunate}Nd values for Bayan Obo ore minerals indicate that the main source(s) for the ores was the lower crust which was depleted in uranium, but enriched in thorium and light rare earth elements for a long period of time. Zircon from a quartz monzonite, located 50 km south of the ore complex and thought to be related to Caledonian subduction, gave an age of 451 Ma, within the range of monazite ages. Textural relations together with the mineral ages favor an epigenetic rather than a syngenetic origin for the orebodies. REE mineralization started around 555 Ma (disseminated monazite in the West, the Main, and south of the East Orebody), but the main mineralization (banded ores) was related to the Caledonian subduction event ca. 474-400 Ma. ?? 1994.

  17. Isotope composition of carbon in the carbonates of the Gumbeykan scheelite deposits in the southern Urals

    SciTech Connect

    Korzhinskii, A.F.; Mamchur, G.P.; Yarynych, O.A.

    1980-10-01

    Through investigations of the isotope composition of carbon of various generations and carbonates from marbles, skarns, and nested and vein scheelite orebodies, the probable source of carbon of these carbonates has been established as a mixture of sedimentary carbonates, carbon dioxide with carbonic acid that was formed by oxidation of the organic matter from sedimentary terrane (..delta..C/sup 13/ - 0.05 to -0.62%). In the calcite and dolomite phenocrysts of marble and the coarse-grained dolostone, containing scheelite, the carbon was lighter (..delta..C/sup 13/ from -0.60 to -0.87%). For the dolomite and ankerite from scheelite pockets of the Balkan deposit and quartz veins of the Buranovo, ..delta..C/sup 13/ varied from -0.44 to -0.87%. The lightest carbon found in strontianite (..delta..C/sup 13/ = -1.32%), located near the coating of the organic matter (..delta..C/sup 13/ = -1.26%) in fractures of the quartz vein of the Buranovo deposit. In the section through the orebodies and near-ore diffusion-metasomatic zones of the Balkan deposit, the lessening of carbon in the carbonates was observed, with increasing distance away from the fracture. ..delta..C/sup 13/ in the altered granitoids ranged from -0.44 to -1.03%; while in the diopside-wollastonite hornfels, from -0.89 to 1.13%. The lessening in weight of the carbon is explained by diffusional fractionation of the isotopes caused apparently by the differential movement of volatile mixtures of carbon during ore-forming processes and the formation of their diffusion-metasomatic zones.

  18. Review of Hydraulic Fracturing for Preconditioning in Cave Mining

    NASA Astrophysics Data System (ADS)

    He, Q.; Suorineni, F. T.; Oh, J.

    2016-12-01

    Hydraulic fracturing has been used in cave mining for preconditioning the orebody following its successful application in the oil and gas industries. In this paper, the state of the art of hydraulic fracturing as a preconditioning method in cave mining is presented. Procedures are provided on how to implement prescribed hydraulic fracturing by which effective preconditioning can be realized in any in situ stress condition. Preconditioning is effective in cave mining when an additional fracture set is introduced into the rock mass. Previous studies on cave mining hydraulic fracturing focused on field applications, hydraulic fracture growth measurement and the interaction between hydraulic fractures and natural fractures. The review in this paper reveals that the orientation of the current cave mining hydraulic fractures is dictated by and is perpendicular to the minimum in situ stress orientation. In some geotechnical conditions, these orientation-uncontrollable hydraulic fractures have limited preconditioning efficiency because they do not necessarily result in reduced fragmentation sizes and a blocky orebody through the introduction of an additional fracture set. This implies that if the minimum in situ stress orientation is vertical and favors the creation of horizontal hydraulic fractures, in a rock mass that is already dominated by horizontal joints, no additional fracture set is added to that rock mass to increase its blockiness to enable it cave. Therefore, two approaches that have the potential to create orientation-controllable hydraulic fractures in cave mining with the potential to introduce additional fracture set as desired are proposed to fill this gap. These approaches take advantage of directional hydraulic fracturing and the stress shadow effect, which can re-orientate the hydraulic fracture propagation trajectory against its theoretical predicted direction. Proppants are suggested to be introduced into the cave mining industry to enhance the

  19. Chemical, geological, and hydrological factors governing radionuclide migration from a formerly used seepage trench: a field study. Environmental Sciences Division publication No. 2202

    SciTech Connect

    Olsen, C.R.; Lowry, P.D.; Lee, S.Y.; Larsen, I.L.; Cutshall, N.H.

    1983-09-01

    A total of 3.2 x 10/sup 7/ L of intermediate-level liquid wastes (ILW) generated from routine Oak Ridge National Laboratory operations, were disposed in Trench 7 between 1962 and 1966. The disposed ILW contained about 10/sup 7/ GBq of fission nuclides (primarily /sup 137/Cs and /sup 90/Sr), activation products (primarily /sup 60/Co), actinides (primarily /sup 232/Th and /sup 238/U decay series nuclides), and transuranics (primarily /sup 241/Pu-/sup 241/Am). Gamma-log profiles of the wells near ILW Trench 7 indicate that the waste liquids seeped along discrete layers parallel to bedding and along the strikes of faults and folds. Although most of the radioactivity has been retained by sorption reactions with the trench fill, soils, and weathered bedrock, groundwater characteristics in the vicinity of ILW Trench 7 are still greatly influenced by the constituents of the waste liquids disposed two decades ago. Radionuclide concentrations in the groundwaters near the north end of ILW Trench 7 undergo seasonal variations, with the lowest activities occurring in fall and winter and the highest activities occurring in the spring and after prolonged rainstorm events. The rise in radioactivity in these wells correlates with a rise in the groundwater level and a concurrent increase in groundwater pH. Although ILW Trench 7 has worked effectively to retain most of the disposed radioactivity, two suspected transport pathways from the trench to a nearby seep area have been identified and both appear to be associated with fault zones. Only the pathway near the north end of the trench appears to be leaching alkalinity and thus affecting the retention capacity for /sup 90/Sr. A groundwater interceptor at the north end of ILW Trench 7 is one possible remedial action to help maintain a dry alkaline environment and ensure the integrity of the trench for nuclide retention.

  20. 1. GENERAL VIEW OF OBSERVATION BUNKERS TO THE EAST OF ...

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

    1. GENERAL VIEW OF OBSERVATION BUNKERS TO THE EAST OF TEST STAND 1-A: IN FOREGROUND, BUILDING 8769, A TWO WINDOW DESIGN (NOT ON SITE PLAN); IN THE MIDDLE DISTANCE, BUILDING 8768, A ONE WINDOW DESIGN "OBSERVATION AND CAMERA BUILDING NO. 2" ON SITE PLAN; IN THE DISTANCE, AT FAR LEFT, BUILDING 8767, A FOUR WINDOW DESIGN "MASTER OBSERVATION AND CAMERA BUILDING NO. 1" ON SITE PLAN. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  1. 9. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, ...

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

    9. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 PALLADIAN WINDOW AT NORTH END OF CENTRAL HALL. 10. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 CENTRAL VIEW OF DOUBLE PARLORS FROM SOUTHWEST PARLOR TOWARD NORTHWEST PARLOR. 11. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 WALLPAPER IN SOUTHWEST PARLOR. 12. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 FIREPLACE IN SOUTHWEST PARLOR. 13. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 WINDOW IN SOUTHWEST PARLOR. 14. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 DETAIL OF WALLPAPER AND WOODWORK IN ... - Eliza Ward House, 2 George Street, Providence, Providence County, RI

  2. Cultural Resources Investigation of the Reservoir Shorelines: Gull Lake, Leech Lake, Pine River and Lake Pokegama. Volume 2. Site Location Data.

    DTIC Science & Technology

    1979-06-01

    affiliation Malmo (Middle Woodland ); Blackduck 4. Location: Sec. 4 Twp. 135N R. 29W Verbal description E NWk north end Upper Gull; just east of bridge over...affiliation Woodland 4. Location: Sec. 25 Twp. 134N R. 30W Verbal description NWk SEk on the southeast arm of the southwest part of Wilson Bay, Gull...mound, village, etc.) mound? burial? 2. Map reference USGS Gull Lake 3. Cultural affiliation Woodland and Historic 4. Location: Sec. 21 Tp. 135N R. 29W

  3. On Point: The United States Army in Operation Iraqi Freedom

    DTIC Science & Technology

    2004-01-01

    come to grips with what happened and what it meant. For all of these reasons, those of us who wrote On Point depended upon help from many people to...shepherds.88 The two battalions’ pincer movements into the city appeared to force some pro-Saddam forces to flee from the north end of As Samawah. However...the way, both instinctively raising their hands to wave as they turned. Shock and horror gripped the two as they realized they were waving at a pair

  4. D0 Silicon Upgrade: End Calorimeter Transfer Bridge Modification

    SciTech Connect

    Stredde, H.J.; /Fermilab

    1996-07-10

    During the assembly of major components into the D0 Detector, a transfer bridge was required to move the North-End Calorimeter from the clean room,over the cable bridge and onto the north sidewalk of the assembly hall. This experiment is now at the beginning stages of the next phase, namely the upgrade of this Detector for future physics research. A major piece of this upgrade is the installation of a solenoid magnet into the Central Calorimeter. In order to accomplish this, the South End Calorimeter has to be removed from the detector and the North End Calorimeter must be moved an additional 20-inch from its nominal open position (total 60-inch movement). The South End Calorimeter will be removed from the detector using the equipment designed for its installation. The calorimeter will be staged on the south sidewalk during the installation of the solenoid magnet and the central tracking systems. The North End Calorimeter is moved 60-inch to give more space between calorimeters during magnet, tracker and cable installation work. This movement will allow the calorimeter to remain coupled to the cryo system. However, this movement requires an extension be added to the center beam. This extension will support the rear wheels of the calorimeter and in the case of the end calorimeters, carry the majority of the weight. The extension is to be a modification of the transfer bridge. This modification, basically has T1 steel blocks added to one end and legs to the sidewalk supports at the other. The T1 steel blocks are notched to fit into the center beam porches and are welded to bridge rails. This design is the same as that for the installation bridge (3740.312-ME-273456), including the welds and weld procedures which are identical in both cases. Since load testing is impractical, the critical welds will be non-destructive tested by ultrasonic means. The laboratory, through the FESS Department, has a contract with M.Q.S. Inspection Inc. The results of this testing will be

  5. Aerial views of the San Andreas Fault

    USGS Publications Warehouse

    Moore, M.

    1988-01-01

    These aerial photographs of the San Andreas fault were taken in 1965 by Robert E. Wallace of the U.S Geological Survey. The pictures were taken with a Rolliflex camera on 20 format black and white flim; Wallace was aboard a light, fixed-wing aircraft, flying mostly at low altitudes. He photographed the fault from San Francisco near its north end where it enters by the Salton Sea. These images represent only a sampling of the more than 300 images prodcued during this project. All the photographs reside in the U.S Geological Survey Library in Menlo Park, California. 

  6. Map showing sampled radiolarian localities in the western Paleozoic and Triassic belt, Klamath Mountains, California

    USGS Publications Warehouse

    Irwin, William P.; Jones, David L.; Blome, Charles D.

    1982-01-01

    The western Paleozoic and Triassic belt, the largest of several major subdivisions of the Klamath Mountains geologic province, extends 300 km northward from the south end of the province in California to the north end of the province in Oregon (see inset map). The rocks of the belt are mainly sedimentary and volcanic, including tuff, cherty tuff, chert, argillite, limestone, and volcanic flows and breccia. They are of oceanic and island arc facies and are highly disarranged tectonically. The southern part of the belt is subdivided into three tectonostratigraphic terranes --- the North Fork, Hayfork, and Rattlesnake Creek terranes. The central and northern parts of the belt are undevided. 

  7. Encyclopedia of U.S. Air Force Aircraft and Missile Systems. Volume 2. Post-World War II Bombers, 1945-1973

    DTIC Science & Technology

    1988-01-01

    This was just as well since it would have hastened the end of the Fort Worth activities . But the monthly production rate of 4 B-36s, a, ’,ter endorsed...in 1944. In 1946, the \\Iutoc Hight 6li.’st Base on the north end of Muroc Dry Lake and the Bombing and tunnery ( Iyew Training Base on t the south end ...34since 1 July 19 5 7 ,64 officially discontinued Hairclipper on 5 March 1958. Yet, demise of the training program did not signify the end of low-level

  8. 33 CFR 110.126 - Monterey Harbor, Calif.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... latitude 36°36′27.5″ N., longitude 121°53′35.0″ W.; thence to latitude 36°36′32.4″ N., longitude 121°53′31.0″ W., in an easterly direction to latitude 36°36′28.8″ N., 121°53′19.0″ W.; thence south to latitude 36°36′23.1″ N., longitude 121°53′19.0″ W.; thence to the north end of Municipal Wharf No. 1...

  9. 33 CFR 110.126 - Monterey Harbor, Calif.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... latitude 36°36′27.5″ N., longitude 121°53′35.0″ W.; thence to latitude 36°36′32.4″ N., longitude 121°53′31.0″ W., in an easterly direction to latitude 36°36′28.8″ N., 121°53′19.0″ W.; thence south to latitude 36°36′23.1″ N., longitude 121°53′19.0″ W.; thence to the north end of Municipal Wharf No. 1...

  10. 33 CFR 110.126 - Monterey Harbor, Calif.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... latitude 36°36′27.5″ N., longitude 121°53′35.0″ W.; thence to latitude 36°36′32.4″ N., longitude 121°53′31.0″ W., in an easterly direction to latitude 36°36′28.8″ N., 121°53′19.0″ W.; thence south to latitude 36°36′23.1″ N., longitude 121°53′19.0″ W.; thence to the north end of Municipal Wharf No. 1...

  11. 33 CFR 110.126 - Monterey Harbor, Calif.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... latitude 36°36′27.5″ N., longitude 121°53′35.0″ W.; thence to latitude 36°36′32.4″ N., longitude 121°53′31.0″ W., in an easterly direction to latitude 36°36′28.8″ N., 121°53′19.0″ W.; thence south to latitude 36°36′23.1″ N., longitude 121°53′19.0″ W.; thence to the north end of Municipal Wharf No. 1...

  12. 33 CFR 110.126 - Monterey Harbor, Calif.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... latitude 36°36′27.5″ N., longitude 121°53′35.0″ W.; thence to latitude 36°36′32.4″ N., longitude 121°53′31.0″ W., in an easterly direction to latitude 36°36′28.8″ N., 121°53′19.0″ W.; thence south to latitude 36°36′23.1″ N., longitude 121°53′19.0″ W.; thence to the north end of Municipal Wharf No. 1...

  13. Adapting coastal structures to a moving relative sea level: Roman Time geoarchaeological evidence from Posillipo promontory (Naples, Italy).

    NASA Astrophysics Data System (ADS)

    Aucelli, Pietro; Cinque, Aldo; Giordano, Francesco; Mattei, Gaia; Pappone, Gerardo; Rizzo, Angela

    2016-04-01

    The Posillipo promontory belongs to the southern periphery the active volcanic complex called Campi Flegrei. Especially the central caldera of CF is well known for offering a rich geoarchaeological record of the vertical ground movements it has been suffering since Roman times; which includes the ruins of Portus Julius (built in 37 BC) presently found between 10 and 5 m bsl and the Middle Ages Lithophaga perforations at about 7m asl on the marble columns of the Serapeo building (Morhange, 2006 and references therein). In order to better constraint the vertical movements suffered by the Posillipo promontory during the last two millennia, we selected three geoarcaeolgical coastal sites (Nisida Roman port, Marechiaro Roman port and Villa Robery) and we studied them by means of both geomorphological observations and geophysical surveys (Side Scan Sonar and Single Beam echo-sounder). Within the submerged Roman port of Nisida, built in the 1st AD, we found two pilae of the ancient pier. The submersion measuring of the well-preserved one provided a palaeo-sea level at 3.1±0.30 m bsl. In the submerged Roman port of Marechiaro, we recognized a still preserved breakwater connected to the tuffaceous sea cliff, and submerged foundations of a 1st century small sea-side villa. Nearby there is also a two-storeyed Roman building (Palazzo degli Spiriti), built in the 1st cent. BC and later restructured to adapt to a phase of subsidence (Gunther 1908). From our submersion measurements, two different paleo-sea levels can be deduced: one for the 1st cent. BC at -4.4 + -0.50 m and another for the 1st cent. AD at -3 + - 0.30 m. Finally, in front of the modern Villa Rosebery the sea bottom shows a sub-horizontal element at -3m to -3.5m bsl, emerged during the 1st BC century. In fact, at least three houses were erected there during said century (Gunther, 1908). As the area was very little elevated, an alignment of pilae was also constructed to protect those houses from the breakers. By

  14. Regional geochemical study of the felsic plutonic rocks in the Nuqrah quadrangle, sheet 25E, Kingdom of Saudi Arabia

    SciTech Connect

    Hall, W.E.; Dellinger, D.; Selner, G.I.

    1985-01-01

    A regional geochemical investigation of the felsic plutonic rocks of the Nuqrah quadrangle, sheet 25 E, Kingdom of Saudi Arabia, in which pan concentrates of 384 wadi samples, and 145 rock samples, were collected, defined two separate and distinct anomalous areas. One area contains Jabal Tuwalah and Jabal Awja, and the other is at the north end of Jabal Safad. Both pan concentrates and the rock samples in the Jabal Tuwalah and Jabal Awja areas contain high concentrations of Be, F, La, Mo, Nb, Pb, Th, U, Sn, Y, and Zr, and the plutons underlying those areas are characterized by high total-count radioactivity. These elements are sited in highly evolved alkalic granites and have not been concentrated into a potentially metalliferous deposit related to a hydrothermal ore system. They may be a potential metal source of the future. Pan-concentration samples collected from wadis draining the north end of Jabal Safad contain anomalous Sn, Mo, Pb, and La. Four samples contain 250 to 1000 ppM of tin. The tin anomaly is associated with a small aplitic pluton intrusive into the Jabal Safad alkalic granite complex. A brief reconnaissance of the area did not reveal any greisen or cassiterite mineralization. However, further exploration work in the area is recommended. 23 refs., 10 figs., 3 tabs.

  15. Lead, arsenic, and polycyclic aromatic hydrocarbons in soil and house dust in the communities surrounding the Sydney, Nova Scotia, tar ponds.

    PubMed Central

    Lambert, Timothy W; Lane, Stephanie

    2004-01-01

    This study evaluated lead, arsenic, and polycyclic aromatic hydrocarbon (PAH) contamination in the residential communities adjacent to the Sydney, Nova Scotia, tar ponds, the area considered Canada's worst contaminated site. The tar pond remediation policy has been limited to the site and some residential properties. We compared background concentrations in 91 soil samples taken 5-20 km from the coke oven site with those in soil samples from the three communities surrounding the tar ponds: Whitney Pier, Ashby, and North End. These surrounding communities were statistically different from background regarding arsenic, lead, and PAHs. Twenty percent of the background soil samples and 95% of the tar pond soil samples were above the Canadian health-risk-based soil guidelines for arsenic (12 ppm), and 5% of the background samples and 80% of the tar pond soil samples were above the Canadian guidelines for lead (140 ppm). Regarding dust lead and arsenic loading, the results provide no evidence that Whitney Pier is significantly different than Ashby and North End. Children in these communities are predicted to have a 1-15% chance of blood lead > 10 microg/dL. The results suggest that lead and arsenic found in the homes originate outside. The lead content of paint in the homes was not evaluated, but consideration of painted wood at the doorway did not confound the results of the study. The results indicate that the residential environment has been adversely affected by PAHs, lead, and arsenic and should be considered for remediation. PMID:14698928

  16. Analytical results, geology, and sample locality map of mercury-sulfur-gypsum mineralization at Crater, Inyo County, California

    USGS Publications Warehouse

    Erickson, M.S.; Marsh, S.P.; Roemer, T.A.

    1984-01-01

    The Crater mercury-su l fur-gypsum ~ineral ized area is located in east-central California along the crest of the Last Chance Range, west of the north end of Death Valley (fig. 1). The area is in the northwest quarter of the Last Chance Range 15-minute quadrangle and occupies the area between 117 39 and 117 45 longitude and 37 10 and 37 15 latitudP.. The area studied lies between 5000 ( 1525 m) and 6000 ( 1830 m) feet above sea level. Relief isgenerally moderate but can be extreme in some places, as at Hanging Rock Canyon (plate 1). The climate is arid, and there are no active streams in the area. The range fronts east and west of the area are precipitous and incised by many steep canyons, whereas the range crest has relatively low relief. The old abandoned town and mine site of Crater 1 ie in this area of low relief. Access to the Crater area is by paved and dirt roads from Big Pine to the west or from the north end of the Death Valley National Monument to the southeast.

  17. Mineralogy and trace-element geochemistry of the high-grade iron ores of the Águas Claras Mine and comparison with the Capão Xavier and Tamanduá iron ore deposits, Quadrilátero Ferrífero, Brazil

    NASA Astrophysics Data System (ADS)

    Spier, Carlos Alberto; de Oliveira, Sonia Maria Barros; Rosière, Carlos Alberto; Ardisson, José Domingos

    2008-02-01

    Tamanduá orebodies shows that the original composition of the itabiritic protore plays a major role in the genesis of high- and low-grade soft ores in the QF. Under the same weathering and structural conditions, the dolomitic itabirite is the more favorable to form high-grade deposits than siliceous itabirite. Field relations at the Águas Claras and Capão Xavier deposits suggest that it is not possible to form huge soft high-grade supergene deposits from siliceous itabirite, unless another control, such as impermeable barriers, had played an important role. The occurrence in the Tamanduá Mine of a large, soft, high-grade orebody formed from siliceous itabirite and closely associated with hypogene hard ore suggests that large, soft, high-grade orebodies of the Quadrilátero Ferrífero, which occur within siliceous itabirite, have a hypogene contribution in their formation.

  18. Sedimentary carbonate-hosted giant Bayan Obo REE-Fe-Nb ore deposit of Inner Mongolia, China; a cornerstone example for giant polymetallic ore deposits of hydrothermal origin

    USGS Publications Warehouse

    Chao, E.C.T.; Back, J.M.; Minkin, J.A.; Tatsumoto, M.; Junwen, Wang; Conrad, J.E.; McKee, E.H.; Zonglin, Hou; Qingrun, Meng; Shengguang, Huang

    1997-01-01

    Detailed, integrative field and laboratory studies of the textures, structures, chemical characteristics, and isotopically determined ages and signatures of mineralization of the Bayan Obo deposit provided evidence for the origin and characteristics favorable for its formation and parameters necessary for defining giant polymetallic deposits of hydrothermal origin. Bayan Obo is an epigenetic, metasomatic, hydrothermal rare earth element (REE)-Fe-Nb ore deposit that is hosted in the metasedimentary H8 dolostone marble of the Middle Proterozoic Bayan Obo Group. The metasedimentary sequence was deposited on the northern continental slope of the North China craton. The mine area is about 100 km south of the suture marking Caledonian subduction of the Mongolian oceanic plate from the north beneath the North China craton. The mineralogy of the deposit is very complex, consisting of more than 120 different minerals, some of which are epigenetic minerals introduced by hydrothermal solutions, and some of which are primary and secondary metamorphic minerals. The major REE minerals are monazite and bastnaesite, whereas magnetite and hematite are the dominant Fe-ore minerals, and columbite is the most abundant Nb mineral. Dolomite, alkali amphibole, fluorite, barite, aegirine augite, apatite, phlogopite, albite, and microcline are the most widespread gangue minerals. Three general types of ores occur at Bayan Obo: disseminated, banded, and massive ores. Broad zoning of these ore types occurs in the Main and East Orebodies. Disseminated ores are in the outermost zone, banded ores are in the intermediate zone, and massive ores are in the cores of the orebodies. On the basis of field relations, host rocks, textures, structures, and mineral assemblages, many varieties of these three types of ores have been recognized and mapped. Isotopic dating of monazite, bastnaesite, aeschynite, and metamorphic and metasomatic alkali amphiboles associated with the deposit provides constraints

  19. Geochemistry and jasper beds from the Ordovician Løkken ophiolite, Norway: origin of proximal and distal siliceous exhalites

    USGS Publications Warehouse

    Grenne, Tor; Slack, John F.

    2005-01-01

    Stratiform beds of jasper (hematitic chert), composed essentially of SiO2 (69-95 wt %) and Fe2O3 (3-25 wt %), can be traced several kilometers along strike in the Ordovician L??kken ophiolite, Norway. These siliceous beds are closely associated with volcanogenic massive sulfide (VMS) deposits and are interpreted as sea-floor gels that were deposited by fallout from hydrothermal plumes in silica-rich seawater, in which plume-derived Fe oxyhydroxide particles promoted flocculation and rapid settling of large (???200 ??m) colloidal particles of silica-iron oxyhydroxide. Concentrations of chalcophile elements in the jasper beds are at the parts per million level implying that sulfide particle fallout was insignificant and that the Si-Fe gel-forming plumes were mainly derived from intermediate- (100??-250??C) to high-temperature (>250??) white smoker-type vents with high Fe/S ratios. The interpreted setting is similar to that of the Lau basin, where high-temperature (280??-334??C) white smoker venting alternates or overlaps with sulfide mound-forming black smoker venting. Ratios of Al, Sc, Th, Hf, and REE to iron are very low and show that the detrital input was <0.1 percent of the bulk jasper. Most jasper beds are enriched in U, V, P, and Mo relative to the North American Shale Composite, reflecting a predominantly seawater source, whereas REE distribution patterns (positive Eu and negative Ce anomalies) reflect variable mixing of hydrothermal solutions with oxic seawater at dilution ratios of ???102 to 104. Trace element variations in the gel precursor to the jasper are thought to have been controlled by coprecipitation and/or adsorption by Fe oxyhydroxide particles that formed by the oxidation of hydrothermal Fe2+ within the variably seawater-diluted hydrothermal plume(s). Thick jasper layers near the H??ydal VMS orebody show distinct positive As/Fe and Sb/Fe anomalies that are attributed to near-vent rapid settling of Si-Fe particles derived from As- and Sb

  20. Origin of the granites and related Sn and Pb-Zn polymetallic ore deposits in the Pengshan district, Jiangxi Province, South China: constraints from geochronology, geochemistry, mineral chemistry, and Sr-Nd-Hf-Pb-S isotopes

    NASA Astrophysics Data System (ADS)

    Xu, Bin; Jiang, Shao-Yong; Luo, Lan; Zhao, Kui-Dong; Ma, Liang

    2016-05-01

    The Pengshan Sn and Pb-Zn polymetallic deposits are located in the south margin of the Jiujiang-Ruichang (Jiurui) district of the Middle-Lower Yangtze River Metallogenic Belt in South China. Four large deposits include Huangjinwa, Zengjialong, Jianfengpo, and Zhangshiba, the former three are Sn-dominant deposits which occur as stratiform orebodies in the contact zones of the Pengshan granites and within the country rock strata, whereas Zhangshiba consists of stratiform Pb-Zn orebodies within the Precambrian metasedimentary strata. In this study, we present results on zircon U-Pb ages, major and trace elements, and mineral chemistry as well as Sr-Nd-Hf isotope data of the granites, Pb and S isotopes of both the Sn-dominant and Pb-Zn dominant deposits, and U-Pb dating of cassiterite from the Pengshan district. SHRIMP and LA-ICP-MS zircon U-Pb dating shows that the Pengshan granites were emplaced in the Early Cretaceous (129-128 Ma), which is in good agreement with the U-Pb dating (130-128 Ma) of cassiterite from the Jianfengpo Sn deposit. The Pengshan granites consist mainly of weakly peraluminous highly fractionated I-type affinity granitic rocks. Detailed elemental and isotopic data suggest that the granites formed by partial melting of Mesoproterozoic metamorphic basement materials with minor input of mantle-derived melts. The mineral chemistry of biotite demonstrates that the Pengshan granitic magma had a low oxygen fugacity, thereby precluding the tin dominantly partitioning into the rock-forming silicate minerals and favoring accumulation in the exsolved residual liquid during magma crystallization stages. Sulfur isotopes show a relatively heavy sulfur isotopic composition from 5.8 to 17.6 ‰, and no difference for sulfur isotopes between the Sn deposits (5.8-13.4 ‰, Huangjinwa, Zengjialong, Jianfengpo) and the Pb-Zn deposit (mostly 7.1-13.0 ‰, except for one 17.6 ‰, Zhangshiba). The sulfur isotope data of pyrite from the host sedimentary rocks show

  1. Behavior of iron-group elements, oxybarometry, and genesis of unique chromite deposits in the Kempirsai massif

    NASA Astrophysics Data System (ADS)

    Chashchukhin, I. S.; Votyakov, S. L.

    2009-04-01

    Ultramafic rocks and high-Cr chromite ore from the Almaz-Zhemchuzhina deposit, the largest in the Main ore field of the Kempirsai massif, have been studied. The detailed mineralogical and geochemical examination of deep structure test and exploratory boreholes allowed us to establish the rough stratification of ultramafic rocks and to demonstrate the position of unique chromite deposits in the generalized vertical section of the southeastern Kempirsai massif. From top to bottom, a barren harzburgite-lherzolite series gives way to an ore-bearing dunite-harzburgite complex with the largest chromite deposits, including the unique Almaz-Zhemchuzhina deposit, in its upper portion and then to pyroxene-free dunite densely impregnated with chromite in the upper part and containing sparsely disseminated chromite at its base. The lower unit is composed of a barren lherzolite-harzburgite series transformed into blastomylonites near the contact with dunite, suggesting a tectonically doubled section in the southeastern part of the massif. The synore asymmetric geochemical zoning developed in the course of formation of chromite deposits as a result of removal of oreforming iron-group elements from the underlying and wall ultramafic rocks into the overlying rocks. Host rocks with disturbed initial proportions of Cr, Fe, Ni, and Mn, together with orebodies, made up ore-bearing zones no less than 1 km in thickness and subdivided into supra-, inter-, and subore subzones. The subore and wall rocks are characterized by partial loss (wt %) of Cr2O3(0.1), NiO (0.04), FeOtot(0.5), and MnO (0.02) and their removal into the interore and supraore (0.03 NiO) subzones. Thus, the subore ultramafic rocks served as a source of ore-forming components, while the interore zone with orebodies occurring therein served as a zone of discharge of these components. Using Mössbauer spectroscopy, the crystal chemistry of iron ions was studied in a representative selection of Cr-spinel samples from rocks

  2. Diamonds in ophiolitic mantle rocks and podiform chromitites: An unsolved mystery

    NASA Astrophysics Data System (ADS)

    Yang, J.; Zhang, Z.; Xu, X.; Ba, D.; Bai, W.; Fabg, Q.; Meng, F.; Chen, S.; Robinson, P. T.; Dobrzhinetskaya, L.

    2009-05-01

    In recent years ultrahigh pressure minerals, such as diamond and coesite, and other unusual minerals were discovered in chromitites of the Luobusa ophiolite in Tibet, and 4 new minerals have been approved by the CNMMN. These results have raised many questionsWhat are the occurrences of the diamonds, what is the source of their carbon and how were they formed? What is the origin of the chromites hosting the diamonds and at what depth did they form? What is the genetic relationship between the diamonds and the host chromitites? In what geological, geophysical and geochemical environments can the diamonds be formed and how are they preserved? The UHP minerals from Luobusa are controversial because they have not been found in situ and because ophiolites are currently believed to form at shallow levels above oceanic spreading centers in suprasubduction zone environments. More detailed study and experimental work are needed to understand the origin and significance of these unusual minerals and investigations of other ophiolites are needed to determine if such minerals occur elsewhere To approach these problems, we have collected two one-ton samples of harzburgite hosting chromitite orebodies in the Luobusa ophiolite in Tibet. The harzburgite samples were taken close to chromitite orebody 31, from which the diamonds, coesite and other unusual minerals were recovered. We processed these two samples in the same manner as the chromitites and discovered numerous diamonds and more than 50 other mineral species. These preliminary results show that the minerals in the harzburgites are similar to those in the chromitites, suggesting a genetic relationship between them. To determine if such UHP and unusual minerals occur elsewhere, we collected about 1.5 t of chromitite from two orebodies in an ultramafic body in the Polar Urals. Thus far, more than 60 different mineral species have been separated from these ores. The most exciting discovery is the common occurrence of diamond, a

  3. Origin of the granites and related Sn and Pb-Zn polymetallic ore deposits in the Pengshan district, Jiangxi Province, South China: constraints from geochronology, geochemistry, mineral chemistry, and Sr-Nd-Hf-Pb-S isotopes

    NASA Astrophysics Data System (ADS)

    Xu, Bin; Jiang, Shao-Yong; Luo, Lan; Zhao, Kui-Dong; Ma, Liang

    2017-03-01

    The Pengshan Sn and Pb-Zn polymetallic deposits are located in the south margin of the Jiujiang-Ruichang (Jiurui) district of the Middle-Lower Yangtze River Metallogenic Belt in South China. Four large deposits include Huangjinwa, Zengjialong, Jianfengpo, and Zhangshiba, the former three are Sn-dominant deposits which occur as stratiform orebodies in the contact zones of the Pengshan granites and within the country rock strata, whereas Zhangshiba consists of stratiform Pb-Zn orebodies within the Precambrian metasedimentary strata. In this study, we present results on zircon U-Pb ages, major and trace elements, and mineral chemistry as well as Sr-Nd-Hf isotope data of the granites, Pb and S isotopes of both the Sn-dominant and Pb-Zn dominant deposits, and U-Pb dating of cassiterite from the Pengshan district. SHRIMP and LA-ICP-MS zircon U-Pb dating shows that the Pengshan granites were emplaced in the Early Cretaceous (129-128 Ma), which is in good agreement with the U-Pb dating (130-128 Ma) of cassiterite from the Jianfengpo Sn deposit. The Pengshan granites consist mainly of weakly peraluminous highly fractionated I-type affinity granitic rocks. Detailed elemental and isotopic data suggest that the granites formed by partial melting of Mesoproterozoic metamorphic basement materials with minor input of mantle-derived melts. The mineral chemistry of biotite demonstrates that the Pengshan granitic magma had a low oxygen fugacity, thereby precluding the tin dominantly partitioning into the rock-forming silicate minerals and favoring accumulation in the exsolved residual liquid during magma crystallization stages. Sulfur isotopes show a relatively heavy sulfur isotopic composition from 5.8 to 17.6 ‰, and no difference for sulfur isotopes between the Sn deposits (5.8-13.4 ‰, Huangjinwa, Zengjialong, Jianfengpo) and the Pb-Zn deposit (mostly 7.1-13.0 ‰, except for one 17.6 ‰, Zhangshiba). The sulfur isotope data of pyrite from the host sedimentary rocks show

  4. Structural localization and origin of compartmentalized fluid flow, Comstock lode, Virginia City, Nevada

    USGS Publications Warehouse

    Berger, B.R.; Tingley, J.V.; Drew, L.J.

    2003-01-01

    Bonanza-grade orebodies in epithermal-style mineral deposits characteristically occur as discrete zones within spatially more extensive fault and/or fracture systems. Empirically, the segregation of such systems into compartments of higher and lower permeability appears to be a key process necessary for high-grade ore formation and, most commonly, it is such concentrations of metals that make an epithermal vein district world class. In the world-class silver- and gold-producing Comstock mining district, Nevada, several lines of evidence lead to the conclusion that the Comstock lode is localized in an extensional stepover between right-lateral fault zones. This evidence includes fault geometries, kinematic indicators of slip, the hydraulic connectivity of faults as demonstrated by veins and dikes along faults, and the opening of a normal-fault-bounded, asymmetric basin between two parallel and overlapping northwest-striking, lateral- to lateral-oblique-slip fault zones. During basin opening, thick, generally subeconomic, banded quartz-adularia veins were deposited in the normal fault zone, the Comstock fault, and along one of the bounding lateral fault zones, the Silver City fault. As deformation continued, the intrusion of dikes and small plugs into the hanging wall of the Comstock fault zone may have impeded the ability of the stepover to accommodate displacement on the bounding strike-slip faults through extension within the stepover. A transient period of transpressional deformation of the Comstock fault zone ensued, and the early-stage veins were deformed through boudinaging and hydraulic fragmentation, fault-motion inversion, and high- and low-angle axial rotations of segments of the fault planes and some fault-bounded wedges. This deformation led to the formation of spatially restricted compartments of high vertical permeability and hydraulic connectivity and low lateral hydraulic connectivity. Bonanza orebodies were formed in the compartmentalized zones of

  5. Noise-based body-wave seismic tomography in an active underground mine.

    NASA Astrophysics Data System (ADS)

    Olivier, G.; Brenguier, F.; Campillo, M.; Lynch, R.; Roux, P.

    2014-12-01

    Over the last decade, ambient noise tomography has become increasingly popular to image the earth's upper crust. The seismic noise recorded in the earth's crust is dominated by surface waves emanating from the interaction of the ocean with the solid earth. These surface waves are low frequency in nature ( < 1 Hz) and not usable for imaging smaller structures associated with mining or oil and gas applications. The seismic noise recorded at higher frequencies are typically from anthropogenic sources, which are short lived, spatially unstable and not well suited for constructing seismic Green's functions between sensors with conventional cross-correlation methods. To examine the use of ambient noise tomography for smaller scale applications, continuous data were recorded for 5 months in an active underground mine in Sweden located more than 1km below surface with 18 high frequency seismic sensors. A wide variety of broadband (10 - 3000 Hz) seismic noise sources are present in an active underground mine ranging from drilling, scraping, trucks, ore crushers and ventilation fans. Some of these sources generate favorable seismic noise, while others are peaked in frequency and not usable. In this presentation, I will show that the noise generated by mining activity can be useful if periods of seismic noise are carefully selected. Although noise sources are not temporally stable and not evenly distributed around the sensor array, good estimates of the seismic Green's functions between sensors can be retrieved for a broad frequency range (20 - 400 Hz) when a selective stacking scheme is used. For frequencies below 100 Hz, the reconstructed Green's functions show clear body-wave arrivals for almost all of the 153 sensor pairs. The arrival times of these body-waves are picked and used to image the local velocity structure. The resulting 3-dimensional image shows a high velocity structure that overlaps with a known ore-body. The material properties of the ore-body differ from

  6. Genesis of the Datuanshan stratabound skarn Cu(-Mo) deposit, Middle-Lower Yangtze Valley, Eastern China: constraints from geology, Re-Os geochronology, mineralogy, and sulfur isotopes

    NASA Astrophysics Data System (ADS)

    Cao, Yi; Gao, Fuping; Du, Yangsong; Du, Yilun; Pang, Zhenshan

    2016-07-01

    Stratabound deposits are the most abundant and economically significant ore type in the Middle-Lower Yangtze River Valley, one of the most important metallogenic belts in China. The Datuanshan deposit is one of the largest and most representative stratabound Cu(-Mo) deposits in the Tongling district of the Middle-Lower Yangtze River metallogenic belt. All the orebodies of the Datuanshan deposit occur around Mesozoic quartz monzodiorite and are tabular or semi-tabular bodies along bedding-parallel faults within upper Permian to Lower Triassic strata. However, discordant and crosscutting relationships (e.g., the host rocks crosscut by skarn- and quartz-sulfide veins, with alteration halos around the veins) have also been found, especially along the skarn-host contact and orebody-host contact, indicating that skarnitization and mineralization postdated the deposition of the host sediments. The skarn consists mainly of prograde garnet and pyroxene and retrograde alteration assemblages of amphibole, epidote, and chlorite, as well as quartz and sulfides. Electron microprobe analyses show that the garnets and pyroxenes are grossular-andradite and hedenbergite-diopside series, respectively, and all samples plot in the field of typical skarn copper deposits worldwide. Molybdenite samples from stratiform copper ores yield Re-Os model ages of 138.2-139.9 Ma with a weighted mean age of 139.2 ± 0.9 Ma. This is reasonably consistent with the ages of the stratiform Mo ores (138.0-140.8 Ma) and genetically related quartz monzodiorite (135.2-139.3 Ma) in the Datuanshan deposit, indicating that the stratiform Cu and Mo mineralization was contemporaneous with emplacement of the quartz monzodiorite magmas in the Early Cretaceous. Fifteen δ34S values for sulfides range from -1.8 to +4.7 ‰, with a mean of 0.5 ‰, indicating that the sulfur was derived mainly from a magmatic source. Moreover, the sulfur isotope values of the ores are consistent with those of Mesozoic intermediate

  7. Coexistence of compositionally heterogeneous chromitites in the Antalya-Isparta ophiolitic suite, SW Turkey: A record of sequential magmatic processes in the sub-arc lithospheric mantle

    NASA Astrophysics Data System (ADS)

    Uysal, Ibrahim; Akmaz, Recep Melih; Saka, Samet; Kapsiotis, Argyrios

    2016-04-01

    The Antalya-Isparta region in southwestern Turkey is well known for its large ophiolitic peridotite exposures, which host various chromite orebodies. These are small-sized, massive to disseminated in texture chromitites occurring in the form of lenses or veinlets, and commonly surrounded by dunite envelopes of variable thickness. Chromitite seams from the Antalya mantle suite are both high- and intermediate-Cr varieties (Cr# = 0.56-0.83), whereas chromitites in the Isparta mantle sequence are exclusively Cr-rich (Cr# = 0.75-0.85). In situ minor and trace element abundances obtained by LA-ICP-MS analyses of unaltered Cr-spinel from the Cr-rich chromitites are comparable to those reported in Cr-spinel of chromitites from typical fore-arc peridotite complexes. However, minor and trace element concentrations in Cr-spinel from intermediate chromitites are dissimilar to those acquired from Cr-spinels of chromitites from well-known back-arc basin-derived ultramafic massifs. Calculation of parental magma compositions indicates that both types of chromitites share a common parentage with progressively fractionating arc-related melts. The studied chromitites are characterized by a systematic enrichment in IPGE [Os, Ir, and Ru (41-317 ppb)] with respect to PPGE [Rh, Pt, and Pd (3-49 ppb)], resulting in negatively-sloping chondrite-normalized PGE patterns that are less fractionated in intermediate chromitites. Their noble mineral assemblage is vastly dominated by tiny (≥ 10 μm) euhedral laurite crystals, followed by subsidiary irarsite and trivial amounts of Os-Ir alloy grains. PGM grains are not encountered in the intermediate chromitites, potentially due to crystallization resulting from PGE-poor melt. Laurite is Os-poor and exhibits a narrow range of Os-for-Ru substitution [Ru/(Ru + Os) = 0.75-0.99]. However, the concomitance of laurite and millerite in the Cr-rich chromitites of the mutual Antalya-Isparta mantle suite is in favour of their precipitation from an Os

  8. Clay alteration and gold deposition in the genesis and blue star deposits, Eureka County, Nevada

    USGS Publications Warehouse

    Drews-Armitage, S. P.; Romberger, S.B.; Whitney, C.G.

    1996-01-01

    The Genesis and Blue Star sedimentary rock-hosted gold deposits occur within the 40-mile-long Carlin trend and are located in Eureka County, Nevada. The deposits are hosted within the Devonian calcareous Popovich Formation, the siliciclastic Rodeo Creek unit and the siliciclastic Vinini Formation. The host rocks have undergone contact metamorphism, decalcification, silicification, argillization, and supergene oxidation. Detailed characterization of the alteration patterns, mineralogy, modes of occurrence, and associated geochemistry of clay minerals resulted in the following classifications: least altered rocks, found distal to the orebody, consisting of both metamorphosed and unmetamorphosed host rock that has not been completely decalcified; and altered rocks, found proximal to the orebody that have been decalcified. Altered rocks are classified further into the following groups based on clay mineral content: silicic, 1 to 10 percent clay; silicicargillic, 10 to 35 percent clay; and argillic, 35 to 80 percent clay. Clay species identified are 1M illite, 2M1 illite, kaolinite, halloysite, and dioctahedral smectite. An early hydrothermal event resulted in the precipitation of euhedral kaolinite and at least one generation of silica. This event occurred contemporaneously with decalcification which increased rock permeability and porosity. A second clay alteration event resulted in the precipitation of hydrothermal 1M illite which replaced hydrothermal kaolinite and is associated with gold deposition. Silver and silica deposition is also associated with this phase of hydrothermal alteration. Hydrothermal alteration was followed by supergene alteration which resulted in the formation of supergene kaolinite, halloysite, and smectite as well as the oxidation of iron-bearing minerals. Supergene clays are concentrated along faults, dike margins, and within rocks containing carbonate. Gold mineralization is not associated with supergene clay minerals within the Genesis and

  9. Geology, mineralization, and geochronology of the Qianhe gold deposit, Xiong'ershan area, southern North China Craton

    NASA Astrophysics Data System (ADS)

    Tang, Ke-Fei; Li, Jian-Wei; Selby, David; Zhou, Mei-Fu; Bi, Shi-Jian; Deng, Xiao-Dong

    2013-08-01

    The Qianhe gold deposit in the Xiong'ershan area is located along the southern margin of the Archean-Paleoproterozoic North China Craton. The deposit consists of six orebodies that are hosted in Paleoproterozoic andesites to basaltic andesites and structurally controlled by roughly EW-trending faults. Individual orebodies comprise auriferous quartz veins and disseminated Au-bearing pyrite within hydrothermally altered rocks on both sides of, or close to, the veins. Ore-related hydrothermal alteration has produced various mixtures of K-feldspar, quartz, sericite, chlorite, epidote, carbonate, and sulfides. Pyrite is the most important ore mineral, associated with minor amounts of galena, sphalerite, and chalcopyrite. Other trace minerals include molybdenite, arsenopyrite, scheelite, rutile, xenotime, and parisite. Gold occurs mostly as native gold and electrum enclosed in pyrite or along microfractures of sulfides and quartz. Microthermometric measurements of primary inclusions in auriferous quartz suggest that gold and associated minerals were precipitated in the range of 160-305 °C from aqueous or carbonic-aqueous fluids with salinities of 6-22 wt% NaCl equiv. Samples of molybdenite coexisting with Au-bearing pyrite have Re-Os model ages of 134-135 Ma, whereas ore-related hydrothermal sericite separates yield 40Ar/39Ar plateau ages between 127 and 124 Ma. The Re-Os and 40Ar/39Ar ages are remarkably consistent with zircon U-Pb ages (134.5 ± 1.5 and 127.2 ± 1.4 Ma; 1 σ) of the biotite monzogranite from the Heyu-intrusive complex and granitic dikes in and close to the Qianhe gold mine, indicating a close temporal and thus possibly genetic relationship between gold mineralization and granitic magmatism in the area. Fluid inclusion waters extracted from auriferous quartz have δD values of -80 to -72 ‰, whereas the calculated δ 18OH2O values range from 3.1 to 3.8 ‰. The hydrogen and oxygen isotopes from this study and previous work indicate that ore fluids

  10. Genesis of the Datuanshan stratabound skarn Cu(-Mo) deposit, Middle-Lower Yangtze Valley, Eastern China: constraints from geology, Re-Os geochronology, mineralogy, and sulfur isotopes

    NASA Astrophysics Data System (ADS)

    Cao, Yi; Gao, Fuping; Du, Yangsong; Du, Yilun; Pang, Zhenshan

    2017-03-01

    Stratabound deposits are the most abundant and economically significant ore type in the Middle-Lower Yangtze River Valley, one of the most important metallogenic belts in China. The Datuanshan deposit is one of the largest and most representative stratabound Cu(-Mo) deposits in the Tongling district of the Middle-Lower Yangtze River metallogenic belt. All the orebodies of the Datuanshan deposit occur around Mesozoic quartz monzodiorite and are tabular or semi-tabular bodies along bedding-parallel faults within upper Permian to Lower Triassic strata. However, discordant and crosscutting relationships (e.g., the host rocks crosscut by skarn- and quartz-sulfide veins, with alteration halos around the veins) have also been found, especially along the skarn-host contact and orebody-host contact, indicating that skarnitization and mineralization postdated the deposition of the host sediments. The skarn consists mainly of prograde garnet and pyroxene and retrograde alteration assemblages of amphibole, epidote, and chlorite, as well as quartz and sulfides. Electron microprobe analyses show that the garnets and pyroxenes are grossular-andradite and hedenbergite-diopside series, respectively, and all samples plot in the field of typical skarn copper deposits worldwide. Molybdenite samples from stratiform copper ores yield Re-Os model ages of 138.2-139.9 Ma with a weighted mean age of 139.2 ± 0.9 Ma. This is reasonably consistent with the ages of the stratiform Mo ores (138.0-140.8 Ma) and genetically related quartz monzodiorite (135.2-139.3 Ma) in the Datuanshan deposit, indicating that the stratiform Cu and Mo mineralization was contemporaneous with emplacement of the quartz monzodiorite magmas in the Early Cretaceous. Fifteen δ34S values for sulfides range from -1.8 to +4.7 ‰, with a mean of 0.5 ‰, indicating that the sulfur was derived mainly from a magmatic source. Moreover, the sulfur isotope values of the ores are consistent with those of Mesozoic intermediate

  11. Sulphur isotope constraints on formation conditions of the Luiswishi ore deposit, Democratic Republic of Congo (DRC)

    NASA Astrophysics Data System (ADS)

    Lerouge, C.; Cailteux, J.; Kampunzu, A. B.; Milesi, J. P.; Fléhoc, C.

    2005-07-01

    Luiswishi is a Congo-type Neoproterozoic sediment-hosted stratiform Cu-Co ore deposit of the Central Africa Copperbelt, located northwest of Lubumbashi (DRC). The ores form two main Cu-Co orebodies hosted by the Mines Subgroup, one in the lower part of the Kamoto Formation and the other at the base of the Dolomitic Shales Formation. Sulphides occur essentially as early parallel layers of chalcopyrite and carrolite, and secondarily as late stockwork sulphides cross-cutting the bedding and the early sulphide generation. Both types of stratiform and stockwork chalcopyrite and carrolite were systematically analyzed for sulphur isotopes, along the lithostratigraphic succession of the Mine Series. The quite similar δ 34S values of stratiform sulphides and late stockwork sulphides suggest an in situ recrystallization or a slight remobilization of stockwork sulphides without attainment of isotopic equilibrium between different sulphide phases (chalcopyrite and carrolite). The distribution of δ 34S values (-14.4‰ to +17.5‰) combined with the lithology indicates a strong stratigraphic control of the sulphur isotope signature, supporting bacterial sulphate reduction during early diagenesis of the host sediments, in a shallow marine to lacustrine environment. Petrological features combined with sulphur isotopic data of sulphides at Luiswishi and previous results on nodules of anhydrite in the Mine Series indicate a dominant seawater/lacustrine origin for sulphates, precluding a possible hydrothermal participation. The high positive δ 34S values of sulphides in the lower orebody at Luiswishi, hosted in massive chloritic-dolomitic siltite (known as Grey R.A.T.), fine-grained stratified dolostone (D.Strat.) and silicified-stromatolitic dolomites alternating with chloritic-dolomitic silty beds (R.S.F.), suggest that they were probably deposited during a period of regression in a basin cut off from seawater. The variations of δ 34S values (i.e. the decrease of δ 34S values

  12. An Inexpensive Way of Teaching Uncertainty and Mineral Exploration Drilling in the Classroom

    NASA Astrophysics Data System (ADS)

    Aquino, J. S.

    2014-12-01

    This presentation is all about inexpensive ways of teaching uncertainty and mineral exploration drilling in the classroom. These labs were developed as an off-shoot of my years of mineral industry experience before I transitioned to geoscience education. I have developed several classroom lab exercises that relate to the role of modeling, uncertainty and prediction in mineral exploration. These lessons are mostly less expensive ($<5/group) hands-on activities that can be differentiated across grade levels. Early in the semester, modeling is explored through the cube and toilet paper roll puzzle lab. This is then immediately followed by the penny experiment that gives a physical meaning to the concept of uncertainty. However, it is the end-of-semester shoebox drilling lab that serves as the culminating activity for modeling, uncertainty and prediction. An object (orebody) is hidden inside a shoebox and the students are challenged to design a drilling program to predict the location and topology of a "mineral deposit". The students' decision on the location of the first few drill holes will be based on how they analyze, synthesize and evaluate simple surface topographic, geologic and geochemical +/- geophysical data overlain on top of the box. Before drilling, students are required to construct several geologic sections that will "model" the shape of the hidden orebody. Using bamboo skewers as their drilling equipment, students then commence their drilling and along the way learn the importance of drill spacing in decreasing uncertainty or increasing confidence. Lastly, the mineral separation lab gives them an opportunity to design another experiment that mimics mineral processing and learns a valuable lesson on the difficulties in recovery and how it relates to entropy (no such thing as 100% recoverability). The last two labs can be further enhanced with economic analysis through incorporation of drilling and processing costs. Students further appreciate the world

  13. Archive of digital chirp subbottom profile data collected during USGS cruise 11BIM01 Offshore of the Chandeleur Islands, Louisiana, June 2011

    USGS Publications Warehouse

    Forde, Arnell S.; Dadisman, Shawn V.; Miselis, Jennifer L.; Flocks, James G.; Wiese, Dana S.

    2013-01-01

    From June 3 to 13, 2011, the U.S. Geological Survey conducted a geophysical survey to investigate the geologic controls on barrier island framework and long-term sediment transport along the oil spill mitigation sand berm constructed at the north end and just offshore of the Chandeleur Islands, LA. This effort is part of a broader USGS study, which seeks to better understand barrier island evolution over medium time scales (months to years). This report serves as an archive of unprocessed digital chirp subbottom data, trackline maps, navigation files, Geographic Information System (GIS) files, Field Activity Collection System (FACS) logs, and formal Federal Geographic Data Committee (FGDC) metadata. Gained (showing a relative increase in signal amplitude) digital images of the seismic profiles are also provided.

  14. Weather support area, floor plan and details. ("Alter COC, Bldg. ...

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

    Weather support area, floor plan and details. ("Alter COC, Bldg. 2605, Weather Support Area, Floor Plan & Details" Also includes a site plan and a finish schedule. The exact location of this construction is obscure, but it appears to be the enclosure of space at the north end of room 101, the "Display Area" or "War Room") Strategic Air Command, Civil Engineering. Drawing no. B-1081, sheet no. 1 of 2, 9 July 1968; project no. MAR-132-8; CE-562; file drawer 2605-9, also 1315. Various scales. 29x41 inches. pencil on paper - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  15. Cultural Resource Assessment of the Test Area North Demolition Landfill at the Idaho National Engineering and Environmental Laboratory

    SciTech Connect

    Brenda R. Pace

    2003-07-01

    The proposed new demolition landfill at Test Area North on the Idaho National Engineering and Environmental Laboratory (INEEL) will support ongoing demolition and decontamination within the facilities on the north end of the INEEL. In June of 2003, the INEEL Cultural Resource Management Office conducted archival searches, field surveys, and coordination with the Shoshone-Bannock Tribes to identify all cultural resources that might be adversely affected by the project and to provide recommendations to protect those listed or eligible for listing on the National Register of Historic Places. These investigations showed that landfill construction and operation would affect two significant cultural resources. This report outlines protective measures to ensure that these effects are not adverse.

  16. Seismic-refraction study of suspected drift-filled bedrock valleys in Ramsey County, Minnesota

    USGS Publications Warehouse

    Woodward, D.G.

    1985-01-01

    A drift-filled bedrock valley was thought to incise the St. Peter aquifer to an altitude between 770 and 800 feet above sea level at the Koppers site. The interpretation of a seismic profile just east of the Koppers site is not conclusive, but suggests that a bedrock valley may be present near the middle of the line. The interpretation of a second seismic profile across the westward extension of the same suspected valley also is not conclusive, but suggests that a bedrock valley may be present at the north end of the line. The optimal field layout for each line at the site (longer shot offsets) could not be obtained because of limited space available in the densely developed residential neighborhoods.

  17. The increase in September precipitation in the Mediterranean region as a result of changes in atmospheric circulation

    NASA Astrophysics Data System (ADS)

    Nojarov, Peter

    2016-05-01

    The study analyzes changes in September precipitation in the Mediterranean region and their possible causes. The research period is 1950-2014. The main finding is that the reduction in aerosol pollution over Europe in the late twentieth century has led to an upward shift of air temperatures in the region, which in turn has reduced the meridional temperature gradient, leading to weakening and shift to the north of the Azores High (the north end of Hadley circulation). This northward shift placed the Mediterranean region in an area with decreasing SLP, which results in an increase in the number or intensity of cyclones, increase in cloudiness and precipitation and a decrease in air temperatures. In the period 1995-2014 the region (especially its eastern part) lies within the boundaries of Inter Tropical Convergence Zone in September.

  18. Arias intensity assessment of liquefaction test sites on the east side of San Francisco Bay affected by the Loma Prieta, California, earthquake of 17 October 1989

    USGS Publications Warehouse

    Kayen, R.E.

    1997-01-01

    Abstract. Uncompacted artificial-fill deposits on the east side of San Francisco Bay suffered severe levels of soil liquefaction during the Loma Prieta earthquake of 17 October 1989. Damaged areas included maritime-port facilities, office buildings, and shoreline transportation arteries, ranging from 65 to 85 km from the north end of the Loma Prieta rupture zone. Typical of all these sites, which represent occurrences of liquefaction-induced damage farthest from the rupture zone, are low cone penetration test and Standard Penetration Test resistances in zones of cohesionless silty and sandy hydraulic fill, and underlying soft cohesive Holocene and Pleistocene sediment that strongly amplified ground motions. Postearthquake investigations at five study sites using standard penetration tests and cone penetration tests provide a basis for evaluation of the Arias intensity-based methodology for assessment of liquefaction susceptibility. ?? 1997 Kluwer Academic Publishers.

  19. A summary of the geology and mineral resources of the Paris Plateau-House Rock Valley area, Coconino County, Arizona

    USGS Publications Warehouse

    Green, Morris W.; Pierson, C.T.; Bauer, D.P.; Umshler, D.B.

    1977-01-01

    The Paria Plateau-House Rock Valley area of north-central Arizona is located on the southwestern edge Of the Colorado Plateau physiographic province in an area underlain by about 5,000 meters of fossiliferous marine and continental sedimentary rock ranging in age from Precambrian through Quaternary. The area, which lies north of the Grand and Marble Canyons, is bounded on the west by the East Kaibab monocline and on the east by the Echo monocline. The Paria Plateau, bounded on the South by the scenic Vermilion Cliffs, is composed of continental red-beds of Triassic and Jurassic age, which dip gently northward at 2? to ? away from the north end of the Marble Platform upon which the Paria Plateau sits.

  20. Geology of Area A, Catak iron deposit, Egrigoz Mountains Kutahya Province, Turkey

    USGS Publications Warehouse

    Barosh, Patrick James

    1972-01-01

    The Catak iron deposit consist of magnetite-bearing lenses distributed along the northeast-trending contact of the north end of. the Egrigoz granitic massif in Kutahya Province. Area A is near the northeast end of the deposit and contains three main irregular magnetite lenses. A body of talc-silicate hornfels, almost surrounded by quartzite and schist , lies a short distance from the contact with quartz monzonite and contains the magnetite-bearing lenses west-northwest to northwest-trending structural grain is expressed by schistosity, joints, shears, lithologic contacts and outcrop patterns, although the mineralized rock and general intrusive contact trend northeast. The ranges of the average content of Fe, Si, and S, determined from drill data are 33.54-53.95 percent; 5.86-12.25 percent; and. 8.33-9.49 percent, respectively.

  1. Provenance of the Tullock Member of the Fort Union Formation, Powder River Basin, Wyoming and Montana: evidence for early Paleocene Laramide uplift

    USGS Publications Warehouse

    Hansley, P.L.; Brown, J.L.

    1993-01-01

    A petrologic and provenance study indicates that Laramide uplifts to the west and south of the Powder River Basin (PRB) were emergent and shedding detritus by early Paleocene time. This conclusion is based largely on the presence of abundant first-cycle carbonate clasts in the northwestern PRB, and metamorphic and igneous clasts and labile heavy-mineral grains in the Tullock throughout the basin. The proximity and composition of the north end of the Bighorn uplift strongly suggest that it was the source for carbonate, igneous, and metamorphic rock fragments in northwestern Tullock outcrops. The conclusions are supported by recent fission-track, palynological, and sedimentological studies that indicate that Laramide-style foreland deformation in southwestern Montana began in late Cenomanian to Turonian time and migrated through central Wyoming to the Colorado Front Range by late Maastrichtian time. -from Authors

  2. Tuscarora area, Nevada: geothermal reservoir assessment case history, northern basin and range. Final report, 1 October 1978-9 September 1980

    SciTech Connect

    Pilkington, H.D.

    1981-08-01

    The Tuscarora prospect is located at the north end of Independence Valley approximately 90 km north-northwest of Elko, Nevada. Geothermal exploration on the prospect consisted of an integrated program of geologic, hydrogeochemical and soil geochemistry studies. Geophysical exploration included heatflow studies, aeromagnetic, self-potential, gravity, dipole-dipole resistivity and magnetotelluric surveys. Exploration drilling includes thirty-two shallow thermal gradient holes, six intermediate depth temperature gradient wells and one 5454 foot test for discovery well. Shallow low-temperature reservoirs were encountered in the Tertiary rocks and in the Paleozoic rocks immediately beneath the Tertiary. Drilling problems forced the deep well to be stopped before the high-temperature reservoir was reached.

  3. Haines - Scagway Submarine Cable Intertie Project, Haines to Scagway, Alaska Final Technical and Construction Report

    SciTech Connect

    See, Alan; Rinehart, Bennie N; Marin, Glen

    1998-11-01

    The Haines to Skagway submarine cable project is located n Taiya Inlet, at the north end of Lynn Canal, in Southeast Alaska. The cable is approximately 15 miles long, with three landings and splice vaults. The cable is 35 kV, 3-Phase, and armored. The cable interconnects the Goat Lake Hydro Project near Skagway with the community of Haines. Both communities are now on 100% hydroelectric power. The Haines to Skagway submarine cable is the result of AP&T's goal of an alternative, economic, and environmentally friendly energy source for the communities served and to eliminate the use of diesel fuel as the primary source of energy. Diesel units will continue to be used as a backup system.

  4. New explorations along the northern shores of Lake Bonneville

    USGS Publications Warehouse

    Oviatt, Charles G.; Miller, D.M.

    1997-01-01

    This field trip begins in Salt Lake City and makes a clockwise circuit of Great Salt Lake, with primary objectives to observe stratigraphie and geomorphic records of Lake Bonneville. Stops include Stansbury Island, Puddle Valley, gravel pits at Lakeside and the south end of the Hogup Mountains, several stops in Curlew Valley and Hansel Valley, and a final stop at the north end of Great Salt Lake east of the Promontory Mountains. Stratigraphie observations at gravel-pit and natural exposures will be linked to interpretations of lake-level change, which were caused by climate change. Evidence of paleoseismic and volcanic activity will be discussed at several sites, and will be tied to the lacustrine stratigraphic record. The trip provides an overview of the history of Lake Bonneville and introduces participants to some new localities with excellent examples of Lake Bonneville landforms and stratigraphy.

  5. Northern Saudi Arabia as seen from STS-62

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Great numbers of circular, center-pivot irrigation plots appear in this west-looking view of northern Saudi Arabia (center to lower left). The entire country between the shifting sands of the Ad Dahna Sand Sea (light colors center and right) and the almost soilless Nejd Plateau (left) has been darkened by thousands of these agricultural fields. The Nejd Plateau is a mass of dark rocks, some volcanic, in northwest Saudi Arabia. The sweep of the Ad Dahna Sand Sea is one of the major features of Saudi Arabia (center and right) as seen from the orbiter. The dunes follow the trend of regional winds (northwesterly in the center of the view) which circulates around the Nejd plateau. The north end of the Red Sea can be seen top left with the Sinai Peninsula and Mediterranean are just visible center top. Iraq is under clouds top right.

  6. Freshwater bryozoa of Tonle Sap, Cambodia.

    PubMed

    Hirose, Masato; Mawatari, Shunsuke F

    2007-06-01

    We identified a collection of freshwater bryozoans from Tonle Sap (meaning Tonle Lake), Cambodia, a body of water fed by the Mekong River and characterized by extreme fluctuations in water level between the wet and dry seasons. The collection also included specimens from the moat of Angkor Wat, located at the north end of the lake. We found four phylactolaemate species (Plumatella bombayensis, Plumatella casmiana, Plumatella vorstmani, Hyalinella lendenfeldi) and one ctenostome species (Hislopia cambodgiensis) from the lake, and only a single, additional phylactolaemate species (Plumatella javanica) from the moat. We provide brief descriptions of these species, photographs of colonies for some, and photomicrographs by light and scanning electron microscopy (SEM) of statoblasts. None of the species encountered in this study is endemic to Cambodia, and the wide distributions of the species are possibly related to the dispersability of floatoblasts by birds. We briefly discuss some of the taxonomic problems surrounding Hislopia cambodgiensis.

  7. Origin and deformation of Holocene shoreline terraces, Yellowstone Lake, Wyoming

    SciTech Connect

    Meyer, G.A.; Locke, W.W.

    1986-08-01

    Geodetic surveys within the Yellowstone caldera have documented active uplift that is most likely caused by magmatic processes in the upper crust. Along the northeast shore of Yellowstone Lake, maximum relative uplift rates are 10 mm/yr for the period 1923-1975. However, information on deformation prior to historic instrumental records has been lacking. In this study, closely spaced data on elevations of postglacial shoreline terraces around the north end of Yellowstone Lake reveal complex tilting. Though most Holocene deformation is probably magma related, the pattern of shoreline tilting deviates significantly from the historic pattern of roughly symmetric inflation of the caldera. Along the northeast shore, where tilt directions of historic and shoreline deformation are similar, differential uplift of a > 2500-yr-old terrace is roughly 10 m; this gives a maximum uplift rate of 4 mm/yr. These unique Holocene terraces may exist due to episodic deformation because vertical movements affecting the lake outlet directly control lake level.

  8. Chryse 'Alien Head'

    NASA Technical Reports Server (NTRS)

    2005-01-01

    26 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an impact crater in Chryse Planitia, not too far from the Viking 1 lander site, that to seems to resemble a bug-eyed head. The two odd depressions at the north end of the crater (the 'eyes') may have formed by wind or water erosion. This region has been modified by both processes, with water action occurring in the distant past via floods that poured across western Chryse Planitia from Maja Valles, and wind action common occurrence in more recent history. This crater is located near 22.5oN, 47.9oW. The 150 meter scale bar is about 164 yards long. Sunlight illuminates the scene from the left/lower left.

  9. In a sea of sticky molasses: The physics of the Boston Molasses Flood

    NASA Astrophysics Data System (ADS)

    Sharp, Nicole; Kennedy, Jordan; Rubinstein, Shmuel

    2016-11-01

    On January 15th, 1919, shortly after 12:40 pm local time, a giant storage tank collapsed in Boston's crowded North End, releasing more than 8.7 million liters of molasses. Contemporary accounts estimated the initial wave was 7.6 meters tall and moved at more than 15 m/s. In moments, molasses engulfed the Commercial Street area, flattening buildings, damaging the elevated train, killing 21 people, and injuring 150 more. Molasses is a viscoelastic fluid 1.5 times as dense as water with a viscosity roughly 4000 times greater. This talk will explore the physics of the Boston Molasses Flood, including the effects of temperature fluctuations and molasses rheology on events leading up to the tank's collapse and their impact on subsequent rescue efforts.

  10. Long-Term Climate Database, Reynolds Creek Experimental Watershed, Idaho, United States

    NASA Astrophysics Data System (ADS)

    Hanson, C. L.; Marks, D.; van Vactor, S. S.

    2001-11-01

    A 33 year (1964-1996), climatic database has been developed for three climate stations on the Reynolds Creek Experimental Watershed located near the north end of the Owyhee Mountains in southwest Idaho. The longest records (1964-1996) are for daily maximum and minimum air temperature. The length of record for other weather elements that include hourly air temperature, relative humidity, dew point temperature, vapor pressure, solar radiation, wind speed and direction, barometric pressure, and daily class A pan evaporation varies, but, in general, the record is from 1974-1996. These data can be accessed from the U.S. Department of Agriculture, Agricultural Research Service, Northwest Watershed Research Center database through the anonymous ftp site: ftp.nwrc.ars.usda.gov.

  11. Monitoring Nitrate, Chlorophyll, and CDOM Cycling in a Reservoir using In Situ Mapping Techniques

    NASA Astrophysics Data System (ADS)

    OConnor, J.; Showers, W. J.; Osburn, C. L.; DeMaster, D. J.

    2013-12-01

    Degradation of surface waters due to increased nutrient loading and subsequent eutrophication is a persistent problem on a global scale. Expanding human populations and their associated development create increased pressure on local watersheds in terms of both point and non-point source pollution. In this study a suite of in situ sensors measuring nitrate concentration, chlorophyll a concentration (Chl a), and chromophoric dissolved organic material (CDOM) fluorescence were deployed from a rapidly moving boat (~32 km/h) in order to identify sources of nutrients and CDOM, and to determine their relationship to eutrophication symptoms in Falls Lake, North Carolina. In addition, water samples were collected throughout the lake and from tributaries of interest for laboratory analysis. Results indicated the three main tributaries at the north end of the lake were the important contributors of both nitrate and CDOM. While two of the three were degraded due to significant effluent discharge from Waste Water Treatment Plants, the third appeared to be impacted by diffuse nutrient sources. However, atmospheric deposition of nitrate and ammonium exceeded tributary input, and the net nutrient loading to the lake was dominated by sediment release of both ammonium and phosphate. No direct relationship between nitrate and Chl a concentrations was observed, but bays that sewage impacted rivers emptied into displayed elevated Chl a values. Water samples from both the lake and streams were analyzed for stable isotopic analysis of δ15N and δ18O composition and were consistent with waste as the primary source of nitrate. Samples were also analyzed for CDOM absorbance and fluorescence through the creation of Excitation and Emission Matrices (EEMs) and the development of a nine component PARAFAC model. Fluorescence values consistently declined from the north end of the lake to the southern end at the dam and water treatment plant intake. Absorbance values at 254 nm (a254) also showed

  12. Land subsidence

    USGS Publications Warehouse

    Holzer, T.L.

    1986-01-01

    In November 1966, sixty percent of Venice, Italy, is inundated by a storm surge that causes waters in the Venetian lagoon to rise more than 6 feet. On December 28, 1971, a janitor at the Washington Elementary School in Johnston City, Illinois, discovers sever cracking of the school. In January 1972, the school is abandoned and subsequently razed. In the 1970's, five homes in New Orleans, Louisiana, are destroyed by gas explosins. In May 198, a 350 feet diameter sink-hole forms in a business area in Winter Park, Florida, and swallows a home and parts of several businesses. In August 1983, Hurricane Alicia slams into the texas Gulf Coast near Houston, Texas, and devastates the 500 home Brownwood subdivision on the north end of Galveston Bay. Homes are torn from their foundations and reduced to rubble. 

  13. LANDSAT image studies as applied to petroleum exploration in Kenya

    NASA Technical Reports Server (NTRS)

    Miller, J. B.

    1975-01-01

    The Chevron-Kenya oil license, acquired in 1972, covers an area at the north end of the Lamu Embayment. Immediately after acquisition, a photogeologic study of the area was made followed by a short field inspection. An interpretation of LANDSAT-1 images as a separate attempt to improve geological knowledge was completed. The method used in the image study, the multispectral characteristics of rock units and terrain, and the observed anomalous features as seen in the LANDSAT imagery are described. It was found that the study helped to define the relationship of the Lamu Embayment and its internal structure with surrounding regional features, such as the East Africa rifting, the Rudolf Trough, the Bur Acaba structural ridge, and the Ogaden Basin.

  14. Geological investigations in the U12b.03 and U12b.04 tunnels, Nevada Test Site

    USGS Publications Warehouse

    Diment, W.H.; Wilmarth, V. R.; McKeown, F.A.; Dickey, D.D.; Hinrichs, E.N.; Botinelly, T.; Roach, C.H.; Byers, F.M.; Hawley, C.C.; Izett, G.A.; Clebsch, Alfred

    1959-01-01

    The U12b.03 and .04 tunnels are part of the U12b (Rainier) tunnel complex that was driven northwestward from the steep east slope of Rainier Mesa (a prominent topographic feature in the northwest part of the Test Site (fig . 2)). The U12b.03 tunnel trends north from a point about 980 feet from the portal of the U12b tunnel (fig. 3). The U12b.03 tunnel consists of 620 feet of tunnel, two alcoves, and a shot chamber. The tunnel is irregular, ranging from 6 to 10 feet in width, and 6 to 9 feet in height. The shot chamber at the north end of the tunnel is 22 feet on each sidee The vertical and minimum cover over the shot chamber are 610 and 510 feet, respectively.

  15. The solubilities of some major and minor element minerals in ground waters associated with a sandstone-hosted uranium deposit.

    USGS Publications Warehouse

    Wanty, R.B.; Chatcham, J.R.; Langmuir, D.

    1987-01-01

    Ground-water samples from 41 wells penetrating basal Oakville sandstone (Miocene) in S Texas were chemically analysed to identify chemical changes related to nearby U orebodies. The coverage included a 240 km2 area which contains several fault-related U deposits. Factors affecting the hydrochemistry include: 1) relatively high permeabilities of buried fluvial-channel sediments; 2) upwards leakage of brines along growth faults into the aquifer; 3) development of a redox interface (Eh = 0 volts) within the aquifer; and 4) the semi-arid climate. Variations in the saturation index (SI) for chemically reduced minerals of U, As, Mo, Se and for associated minerals such as pyrite outlined the position of known deposits. The SI increases towards zero as the deposits are approached from updip distances of 3-4.5 km, then decreases again downdip. The radiogenic pathfinders Ra and Rn showed very strong anomalies with ore, but diminished to background levels at short distances from ore. A strong He anomaly is deflected in the direction of ground-water flow away from the ore.-R.A.H.

  16. Iron isotope and REE+Y composition of the Cauê banded iron formation and related iron ores of the Quadrilátero Ferrífero, Brazil

    NASA Astrophysics Data System (ADS)

    Mendes, Mônica; Lobato, Lydia M.; Kunzmann, Marcus; Halverson, Galen P.; Rosière, Carlos A.

    2017-02-01

    The Minas Supergroup banded iron formations (BIFs) of the Brazilian Quadrilátero Ferrífero (QF) mineral province experienced multiple deformational events synchronous with hypogene mineralization, which resulted in the metamorphism of BIFs to itabirites and their upgrade to high-grade iron ore. Here, we present rare earth element and yttrium (REE+Y) compositions together with iron isotope ratios of itabirites and their host iron orebodies from 10 iron deposits to constrain environmental conditions during BIF deposition and the effects of hypogene iron enrichment. The REE+Y characteristics of itabirites (positive Eu anomaly and LREE depletion) indicate hydrothermal iron contribution to the Minas basin. Iron isotope data and Ce anomalies suggest BIFs were precipitated by a combination of anoxic biological-mediated ferrous iron oxidation and abiotic oxidation in an environment with free oxygen (such as an oxygen oasis), perhaps related to increase in oxygen concentrations before the Great Oxidation Event (GOE). The similarity of the REE+Y composition of the itabirites from the different QF deformational domains, as well as to other Superior-type BIFs, indicates that the metamorphism and synchronous hydrothermal mineralization did not significantly affect the geochemical signature of the original BIFs. However, iron isotope compositions of iron ore vary systematically between deformational domains of the QF, likely reflecting the specific mineralization features in each domain.

  17. A study of radionuclides, metals and stable lead isotope ratios in sediments and soils in the vicinity of natural U-mineralisation areas in the Northern Territory.

    PubMed

    Frostick, A; Bollhöfer, A; Parry, D

    2011-10-01

    Australian guidelines recommend that tailings materials from uranium (U) mining and milling be contained without any detrimental impact on the environment for at least 1000 years. Natural analogue sites are being investigated to determine if they can provide data on the rates of natural erosion processes which occur over these timescales, for input into predictive geomorphic computer models. This paper presents radionuclide, metal and stable lead (Pb) isotope data from sediment cores and surface soils in the vicinity of two mineralised areas in the Alligator Rivers Region. Surface scrapes from the natural Anomaly #2, south of the Ranger mineral lease, exhibit radiogenic (206)Pb/(207)Pb and (208)Pb/(207)Pb ratios, and elevated U and metal concentrations typical for a near surface U anomaly. In contrast, samples taken from the Koongarra mineral lease (KML) show radionuclide activity and metal concentrations similar to natural areas elsewhere in the Alligator Rivers Region and Pb isotope ratios are closer to present day average crustal ratios (PDAC), as the orebodies at KML are covered by surficial sand. A sediment core collected from Anbangbang Billabong, downstream of KML, exhibits small variations in Pb isotope ratios that indicate that approximately 1% of the upper sediments in the sediment core may be derived from material originating from the U anomaly at Koongarra.

  18. Geochemistry of vanadium in an epigenetic, sandstone-hosted vanadium- uranium deposit, Henry Basin, Utah

    USGS Publications Warehouse

    Wanty, R.B.; Goldhaber, M.B.; Northrop, H.R.

    1990-01-01

    The epigenetic Tony M vanadium-uranium orebody in south-central Utah is hosted in fluvial sandstones of the Morrison Formation (Upper Jurassic). Measurements of the relative amounts of V+3 and V +4 in ore minerals show that V+3 is more abundant. Thermodynamic calculations show that vanadium was more likely transported to the site of mineralization as V+4. The ore formed as V+4 was reduced by hydrogen sulfide, followed by hydrolysis and precipitation of V+3 in oxide minerals or chlorite. Uranium was transported as uranyl ion (U+6), or some complex thereof, and reduced by hydrogen sulfide, forming coffinite. Detrital organic matter in the rocks served as the carbon source for sulfate-reducing bacteria. Vanadium most likely was derived from the dissolution of iron-titanium oxides. Uranium probably was derived from the overlying Brushy Basin Member of the Morrison Formation. Previous studies have shown that the ore formed at the density-stratified interface between a basinal brine and dilute meteoric water. The mineralization processes described above occurred within the mixing zone between these two fluids. -from Authors

  19. Geologic map of the Weka Dur gold deposit, Badakhshan Province, Afghanistan, modified from the 1967 original map compilation of M.P. Guguev and others

    USGS Publications Warehouse

    Peters, Stephen G.; Stettner, Will R.; Masonic, Linda M.

    2014-01-01

    The Weka Dur gold deposit lies in a cluster of other gold deposits in Badakhshan Province (Ragh district), such as the Kadar, Nesheb Dur, and Rishaw gold occurrences. These gold occurrences lie within a zone of late Hercynian folding and are most likely related to fluids that originated from orogenic processes. The Weka Dur deposit is the largest recorded gold occurrence in Afghanistan and is hosted in Proterozoic mica schist and amphibolite that is intruded by diabase dikes and other intrusive rocks. The tabular orebody is 350 meters (m) long and 2 m wide and can be traced downdip for 110 m. Mineralization consists of ochreous, brecciated schists containing high gold concentrations along gently and steeply dipping fissures. The brecciated rocks grade to 46.7 grams per ton (g/t) silver and contain arsenopyrite, galena, chalcopyrite, and scheelite. Trenches and adits were constructed, mapped, and sampled during the 1960s. Calculated resources are 958.3 kilograms of gold, averaging 4.1 g/t gold.

  20. Tempo of magma degassing and the genesis of porphyry copper deposits

    NASA Astrophysics Data System (ADS)

    Chelle-Michou, Cyril; Rottier, Bertrand; Caricchi, Luca; Simpson, Guy

    2017-01-01

    Porphyry deposits are copper-rich orebodies formed by precipitation of metal sulphides from hydrothermal fluids released from magmatic intrusions that cooled at depth within the Earth’s crust. Finding new porphyry deposits is essential because they are our largest source of copper and they also contain other strategic metals including gold and molybdenum. However, the discovery of giant porphyry deposits is hindered by a lack of understanding of the factors governing their size. Here, we use thermal modelling and statistical simulations to quantify the tempo and the chemistry of fluids released from cooling magmatic systems. We confirm that typical arc magmas produce fluids similar in composition to those that form porphyry deposits and conclude that the volume and duration of magmatic activity exert a first order control on the endowment (total mass of deposited copper) of economic porphyry copper deposits. Therefore, initial magma enrichment in copper and sulphur, although adding to the metallogenic potential, is not necessary to form a giant deposit. Our results link the respective durations of magmatic and hydrothermal activity from well-known large to supergiant deposits to their metal endowment. This novel approach can readily be implemented as an additional exploration tool that can help assess the economic potential of magmatic-hydrothermal systems.

  1. Passive airborne EM and ground IP\\resistivity results over the Romero intermediate sulphidation epithermal gold deposits, Dominican Republic

    NASA Astrophysics Data System (ADS)

    Legault, Jean M.; Niemi, Jeremy; Brett, Jeremy S. Zhao, Shengkai; Han, Zihao; Plastow, Geoffrey C.

    2016-04-01

    The Romero gold-copper-zinc-silver deposits are located in the Province of San Juan, Dominican Republic, ~165 km west-north-west of Santo Domingo. Romero and Romero South orebodies contain stratabound gold mineralisation with copper, silver and zinc of intermediate sulphidation (IS), epithermal style. The gold mineralisation is associated with disseminated to semi-massive sulphides, sulphide veinlets and quartz-sulphide veins within quartz-pyrite, quartz-illite-pyrite and illite-chlorite-pyrite alteration. Ground direct current (DC) resistivity and induced polarisation (IP) supported by ground magnetics remain the preferred geophysical targeting tools for drill follow-up along with geologic mapping and geochemistry. However, Z-axis tipper electromagnetics (ZTEM) passive airborne electromagnetics (AEM) and magnetics have recently also been applied with success for reconnaissance mapping of deep alteration and fault structures regionally. The airborne ZTEM-magnetic surveys, supported by three-dimensional (3D) inversions, show good correlation with the ground IP\\resistivity surveys in the Romero and Romero South gold-copper-zinc-silver IS deposit area. The results have provided targets for ground follow-up and deep targeted drilling, and were successful in identifying a previously unknown deep (>500 m) continuity between the Romero and Romero South deposits.

  2. Role of degassing of the Noril'sk nickel deposits in the Permian-Triassic mass extinction event.

    PubMed

    Le Vaillant, Margaux; Barnes, Stephen J; Mungall, James E; Mungall, Emma L

    2017-03-07

    The largest mass extinction event in Earth's history marks the boundary between the Permian and Triassic Periods at circa 252 Ma and has been linked with the eruption of the basaltic Siberian Traps large igneous province (SLIP). One of the kill mechanisms that has been suggested is a biogenic methane burst triggered by the release of vast amounts of nickel into the atmosphere. A proposed Ni source lies within the huge Noril'sk nickel ore deposits, which formed in magmatic conduits widely believed to have fed the eruption of the SLIP basalts. However, nickel is a nonvolatile element, assumed to be largely sequestered at depth in dense sulfide liquids that formed the orebodies, preventing its release into the atmosphere and oceans. Flotation of sulfide liquid droplets by surface attachment to gas bubbles has been suggested as a mechanism to overcome this problem and allow introduction of Ni into the atmosphere during eruption of the SLIP lavas. Here we use 2D and 3D X-ray imagery on Noril'sk nickel sulfide, combined with simple thermodynamic models, to show that the Noril'sk ores were degassing while they were forming. Consequent "bubble riding" by sulfide droplets, followed by degassing of the shallow, sulfide-saturated, and exceptionally volatile and Cl-rich SLIP lavas, permitted a massive release of nickel-rich volcanic gas and subsequent global dispersal of nickel released from this gas as aerosol particles.

  3. Integration of multi-source and multi-scale datasets for 3D structural modeling for subsurface exploration targeting, Luanchuan Mo-polymetallic district, China

    NASA Astrophysics Data System (ADS)

    Wang, Gongwen; Ma, Zhenbo; Li, Ruixi; Song, Yaowu; Qu, Jianan; Zhang, Shouting; Yan, Changhai; Han, Jiangwei

    2017-04-01

    In this paper, multi-source (geophysical, geochemical, geological and remote sensing) datasets were used to construct multi-scale (district-, deposit-, and orebody-scale) 3D geological models and extract 3D exploration criteria for subsurface Mo-polymetallic exploration targeting in the Luanchuan district in China. The results indicate that (i) a series of region-/district-scale NW-trending thrusts controlled main Mo-polymetallic forming, and they were formed by regional Indosinian Qinling orogenic events, the secondary NW-trending district-scale folds and NE-trending faults and the intrusive stock structure are produced based on thrust structure in Caledonian-Indosinian orogenic events; they are ore-bearing zones and ore-forming structures; (ii) the NW-trending district-scale and NE-trending deposit-scale normal faults were crossed and controlled by the Jurassic granite stocks in 3D space, they are associated with the magma-skarn Mo polymetallic mineralization (the 3D buffer distance of ore-forming granite stocks is 600 m) and the NW-trending hydrothermal Pb-Zn deposits which are surrounded by the Jurassic granite stocks and constrained by NW-trending or NE-trending faults (the 3D buffer distance of ore-forming fault is 700 m); and (iii) nine Mo polymetallic and four Pb-Zn targets were identified in the subsurface of the Luanchuan district.

  4. Geological modelling of mineral deposits for prediction in mining

    NASA Astrophysics Data System (ADS)

    Sides, E. J.

    Accurate prediction of the shape, location, size and properties of the solid rock materials to be extracted during mining is essential for reliable technical and financial planning. This is achieved through geological modelling of the three-dimensional (3D) shape and properties of the materials present in mineral deposits, and the presentation of results in a form which is accessible to mine planning engineers. In recent years the application of interactive graphics software, offering 3D database handling, modelling and visualisation, has greatly enhanced the options available for predicting the subsurface limits and characteristics of mineral deposits. A review of conventional 3D geological interpretation methods, and the model struc- tures and modelling methods used in reserve estimation and mine planning software packages, illustrates the importance of such approaches in the modern mining industry. Despite the widespread introduction and acceptance of computer hardware and software in mining applications, in recent years, there has been little fundamental change in the way in which geology is used in orebody modelling for predictive purposes. Selected areas of current research, aimed at tackling issues such as the use of orientation data, quantification of morphological differences, incorporation of geological age relationships, multi-resolution models and the application of virtual reality hardware and software, are discussed.

  5. Diffusional transport and fluid connectivity in mineral aggregates. Final report [for the period August 15, 1994 to August 15, 1999

    SciTech Connect

    Yund, Richard; Farver, John

    1999-08-12

    The objectives of this study were to determine diffusional transport rates of oxygen and selected geologically and environmentally important cations in polycrystalline mineral aggregates. The samples included both natural and hot-pressed single and polyphase aggregates of common mineralogies. In addition to determining grain boundary diffusion rates in these samples, bulk diffusivity measurements were made to evaluate the connectivity of common geological fluids as a function of temperature, pressure, fluid composition and volume fraction, mineralogy (anisotropy of interfacial energies), and stress state in the solid. An integral part of these investigations was the detailed characterization of the sample microstructures using SEM and TEM in order to evaluate whether a correlation between microstructure observations and bulk diffusional transport distances can be established, thus providing a valuable tool for predicting diffusional transport and fluid connectivity in natural samples. Applications of these data include evaluating the retentiveness of different geological medium for the isolation and confinement of nuclear and chemical wastes, modeling the migration of formation fluids and hydrocarbons through different rock types to refine exploration and development strategies for more efficient oil and natural gas recovery, and determining fluid/rock interactions and thermal histories from isotope systematics which, among other things, provide models for modern-day geothermal/hydrothermal energy systems and ore-body deposition associated with fossil hydrothermal systems.

  6. Scaling behavior and the effects of heterogeneity on shallow seismic imaging of mineral deposits: A case study from Brunswick No. 6 mining area, Canada

    NASA Astrophysics Data System (ADS)

    Cheraghi, Saeid; Malehmir, Alireza; Bellefleur, Gilles; Bongajum, Emmanuel; Bastani, Mehrdad

    2013-03-01

    We have studied the scaling behavior of compressional-wave velocity and density logs from an exploration borehole that extends down to about 700 m depth in the Brunswick No. 6 mining area, Bathurst Mining Camp, Canada. Using statistical methods, vertical and horizontal scale lengths of heterogeneity were estimated. Vertical scale length estimates from the velocity, density and calculated acoustic impedance are 14 m, 33 m, and about 20 m, respectively. Although the estimated scale length for the acoustic impedance implies a weak scattering environment, elastic finite difference modeling of seismic wave propagation in 2D heterogeneous media demonstrates that even this weak scattering medium can mask seismic signals from small, but yet economically feasible, massive sulfide deposits. Further analysis of the synthetic seismic data suggests that in the presence of heterogeneity, lenticular-shaped targets may only exhibit incomplete diffraction signals whereby the down-dip tails of these diffractions are mainly visible on the stacked sections. Therefore, identification of orebody generated diffractions is much easier on the unmigrated stacked sections than on migrated stacked sections. The numerical seismic modeling in 2D heterogeneous media indicates that in the presence of large horizontal, but small vertical scale lengths (structural anisotropy), identification of massive sulfide deposits is possible, but their delineation at depth requires detailed velocity modeling and processing algorithms which can handle the anisotropy.

  7. The nature and genesis of marginal Cu-PGE-Au sulphide mineralisation in Paleogene Macrodykes of the Kangerlussuaq region, East Greenland

    NASA Astrophysics Data System (ADS)

    Holwell, David A.; Abraham-James, Thomas; Keays, Reid R.; Boyce, Adrian J.

    2012-01-01

    The Kangerlussuaq region of East Greenland hosts a variety of early Tertiary extrusive and intrusive igneous rocks related to continental break up and the passage of the ancestral Iceland plume. These intrusive bodies include a number of gabbroic macrodykes, two of which—the Miki Fjord Macrodyke, and the newly discovered Togeda Macrodyke—contain Cu-PGE-Au sulphide mineralisation along their margins. Sulphides occur as disseminated interstitial blebs and rounded globules of chalcopyrite and pyrrhotite with some Fe-Ti oxides and platinum-group minerals, comprising largely Pd bismuthides and tellurides. The globules are interpreted to have formed from fractionation of trapped droplets of an immiscible Cu- and Pd-rich sulphide melt and show geopetal indicators. Sulphur isotopes imply a local crustal source of S in these from pyritic sediments of the Kangerlussuaq Basin. Thus, generation of these sulphide occurrences was controlled by local country rock type. Low Ni/Cu and Pt/Pd ratios, also present in the Platinova reefs in the Skaergaard Intrusion, indicate that early fractionation of olivine may have depleted the magma of Ni and suggest the likely presence of a large magma chamber at depth. Xenoliths of Ni-rich olivine cumulates in the Miki Fjord Macrodyke may have been sourced from such a body. The location of thus far unidentified conduit or feeder zones to the macrodykes beneath the present day surface may represent potential targets for more massive sulphide orebodies.

  8. Tilting history of the San Manuel-Kalamazoo porphyry system, southeastern Arizona

    USGS Publications Warehouse

    Force, E.R.; Dickinson, W.R.; Hagstrum, J.T.

    1995-01-01

    The Laramide San Manuel-Kalamazoo porphyry system of Arizona has been pivotal in concepts of both extensional tectonics and alteration-mineralization zoning. This paper reexamines the tilting history in light of new work in the region and reinterprets the geometry of the deposit. The porphyry mineralization occurs in and near an intrusion of Laramide San Manuel porphyry in Precambrian Oracle Granite. The area has an extremely complicated history of Tertiary crustal extension and fanglomerate deposition, but the blocks containing the two main fragments of the original orebody were involved in only the later parts of this history and are less tilted than other nearby blocks. Originally horizontal features of mid-Tertiary age are tilted about 30??, those of Laramide age about 35??, and those of pre-Laramide age about 45?? to the northeast. Paleomagnetism of the porphyry intrusion itself suggests tilting of about 33??. The data thus suggest that postemplacement tilt of the Laramide porphyry system was 30?? to 35?? and that virtually all of it was mid-Tertiary in age. -from Authors

  9. Lebediny gold deposit, Central Aldan: Mineral parageneses, stages, and formation conditions

    NASA Astrophysics Data System (ADS)

    Dobrovol'skaya, M. G.; Razin, M. V.; Prokof'ev, V. Yu.

    2016-07-01

    The mineral parageneses and succession of their formation are considered for the first time for the Zverevsky, Orekhovy, and Vodonosny ore lodes of the Lebediny gold deposit and the Radostny prospect in the Central Aldan ore district, which are genetically related to the epoch of Mesozoic tectonomagmatic reactivation. The orebodies, represented by two morphological varieties—ribbonlike lodes and steeply dipping veins—are hosted in lower part of the Vendian-Cambrian dolomitic sequence, which is cut through by Mesozoic subalkaline intrusive bodies. The chemistry of fahlore and rare minerals, including native gold and bismuth, altaite, aikinite, tetradymite, and sulfosalts of lillianite series, has been studied. Native gold is related to the late hydrothermal process and occurs in skarn and in quartz-tremolite-sulfide and quartz-carbonate-sulfide veins. The data on stable sulfur (δ34S) isotopes of sulfides, oxygen (δ18O) and carbon (δ13C) isotopes of carbonates, as well as on fluid inclusions in various generations of tremolite and quartz, provide evidence for the heterogeneity of ore-bearing solutions, their relationships to magmatism, the depth of the source feeding each specific lode, and different sources of ore-forming hydrothermal solutions.

  10. Fluid inclusion and sulphur isotope evidence for syntectonic mineralisation at the Elura mine, southeastern Australia

    NASA Astrophysics Data System (ADS)

    Seccombe, P. K.

    1990-10-01

    Fluid inclusion and sulphur isotope data for the discordant, metasediment-hosted massive sulphide deposit at Elura are consistent with a syntectonic origin of the orebodies. Thermometric and laser Raman microprobe analyses indicate that two-phase, primary fluid inclusions are low salinity and H2O-CO2-CH4 types. Inclusion fluids from quartz in ore yield homogenisation temperatures (Th) ranging from 298 ° to 354 °C (mean 320 °C). They are likely to have been trapped close to the solvus of the H2O-CO2-(CH4-NaCl) system and thus should give temperatures of the mineralising fluid. An additional, low Th population of later fluid inclusions is recognised in quartz from ore and syntectonic extension veins in the adjacent wallrock. Th's for these low CO2bearing inclusions range from 150 to 231 °C (mean 190 °C), and should be considerably lower than true trapping temperatures. Sulphur isotopic composition (δ34S) of pyrite, sphalerite, pyrrhotite and galena ranges from 4.7 to 12.6% and indicates a sulphur source from underlying Cobar Supergroup metasediments. An average temperature of 275 °C from the sphalerite-galena sulphur isotopic thermometer suggests isotopic re-equilibration below peak metamorphic temperatures.

  11. 234U /238U and 230Th /234U activity ratios in the colloidal phases of aquifers in lateritic weathered zones

    NASA Astrophysics Data System (ADS)

    Short, Stephen A.; Lowson, Richard T.; Ellis, John

    1988-11-01

    A procedure was developed for comparing solute and colloid phases of groundwaters in contact with uranium ore bodies at Nabarlek and Koongarra in the Alligator Rivers region, Northern Territory, Australia. Single-pass ultrafiltration of large volumes with cut-offs of 18 nm and 1 μm was used. Colloids were composed of Fe and Si species with sorbed U and U daughters. Uranium isotopes were mostly present as soluble species. Thorium was significantly associated with the colloids. The 234U /238U activity ratios (ARs) were similar in solute and colloid phases close to the ore bodies but further down-gradient colloids were generally more depleted of 234U than the solute. The 230Th /234U ARs rose from very low values for both solute and colloid phases close to the ore bodies through several orders of magnitude to much higher values further down-gradient. Colloid 230Th /234U ARs were always significantly greater than solute ARs. Results were consistent with a systematic leaching of U from colloids going down-gradient and very little mobilization of ore-body 230Th relative to U. Ubiquitous complexed 232Th appeared to suppress the solubility of 230Th.

  12. Uranium immobilization and nuclear waste

    SciTech Connect

    Duffy, C.J.; Ogard, A.E.

    1982-02-01

    Considerable information useful in nuclear waste storage can be gained by studying the conditions of uranium ore deposit formation. Further information can be gained by comparing the chemistry of uranium to nuclear fission products and other radionuclides of concern to nuclear waste disposal. Redox state appears to be the most important variable in controlling uranium solubility, especially at near neutral pH, which is characteristic of most ground water. This is probably also true of neptunium, plutonium, and technetium. Further, redox conditions that immobilize uranium should immobilize these elements. The mechanisms that have produced uranium ore bodies in the Earth's crust are somewhat less clear. At the temperatures of hydrothermal uranium deposits, equilibrium models are probably adequate, aqueous uranium (VI) being reduced and precipitated by interaction with ferrous-iron-bearing oxides and silicates. In lower temperature roll-type uranium deposits, overall equilibrium may not have been achieved. The involvement of sulfate-reducing bacteria in ore-body formation has been postulated, but is uncertain. Reduced sulfur species do, however, appear to be involved in much of the low temperature uranium precipitation. Assessment of the possibility of uranium transport in natural ground water is complicated because the system is generally not in overall equilibrium. For this reason, Eh measurements are of limited value. If a ground water is to be capable of reducing uranium, it must contain ions capable of reducing uranium both thermodynamically and kinetically. At present, the best candidates are reduced sulfur species.

  13. Stochastic production phase design for an open pit mining complex with multiple processing streams

    NASA Astrophysics Data System (ADS)

    Asad, Mohammad Waqar Ali; Dimitrakopoulos, Roussos; van Eldert, Jeroen

    2014-08-01

    In a mining complex, the mine is a source of supply of valuable material (ore) to a number of processes that convert the raw ore to a saleable product or a metal concentrate for production of the refined metal. In this context, expected variation in metal content throughout the extent of the orebody defines the inherent uncertainty in the supply of ore, which impacts the subsequent ore and metal production targets. Traditional optimization methods for designing production phases and ultimate pit limit of an open pit mine not only ignore the uncertainty in metal content, but, in addition, commonly assume that the mine delivers ore to a single processing facility. A stochastic network flow approach is proposed that jointly integrates uncertainty in supply of ore and multiple ore destinations into the development of production phase design and ultimate pit limit. An application at a copper mine demonstrates the intricacies of the new approach. The case study shows a 14% higher discounted cash flow when compared to the traditional approach.

  14. The natural neighbor series manuals and source codes

    NASA Astrophysics Data System (ADS)

    Watson, Dave

    1999-05-01

    This software series is concerned with reconstruction of spatial functions by interpolating a set of discrete observations having two or three independent variables. There are three components in this series: (1) nngridr: an implementation of natural neighbor interpolation, 1994, (2) modemap: an implementation of natural neighbor interpolation on the sphere, 1998 and (3) orebody: an implementation of natural neighbor isosurface generation (publication incomplete). Interpolation is important to geologists because it can offer graphical insights into significant geological structure and behavior, which, although inherent in the data, may not be otherwise apparent. It also is the first step in numerical integration, which provides a primary avenue to detailed quantification of the observed spatial function. Interpolation is implemented by selecting a surface-generating rule that controls the form of a `bridge' built across the interstices between adjacent observations. The cataloging and classification of the many such rules that have been reported is a subject in itself ( Watson, 1992), and the merits of various approaches have been debated at length. However, for practical purposes, interpolation methods are usually judged on how satisfactorily they handle problematic data sets. Sparse scattered data or traverse data, especially if the functional values are highly variable, generally tests interpolation methods most severely; but one method, natural neighbor interpolation, usually does produce preferable results for such data.

  15. Quantitative interpretation of airborne gravity gradiometry data for mineral exploration

    NASA Astrophysics Data System (ADS)

    Martinez, Cericia D.

    In the past two decades, commercialization of previously classified instrumentation has provided the ability to rapidly collect quality gravity gradient measurements for resource exploration. In the near future, next-generation instrumentation are expected to further advance acquisition of higher-quality data not subject to pre-processing regulations. Conversely, the ability to process and interpret gravity gradiometry data has not kept pace with innovations occurring in data acquisition systems. The purpose of the research presented in this thesis is to contribute to the understanding, development, and application of processing and interpretation techniques available for airborne gravity gradiometry in resource exploration. In particular, this research focuses on the utility of 3D inversion of gravity gradiometry for interpretation purposes. Towards this goal, I investigate the requisite components for an integrated interpretation workflow. In addition to practical 3D inversions, components of the workflow include estimation of density for terrain correction, processing of multi-component data using equivalent source for denoising, quantification of noise level, and component conversion. The objective is to produce high quality density distributions for subsequent geological interpretation. I then investigate the use of the inverted density model in orebody imaging, lithology differentiation, and resource evaluation. The systematic and sequential approach highlighted in the thesis addresses some of the challenges facing the use of gravity gradiometry as an exploration tool, while elucidating a procedure for incorporating gravity gradient interpretations into the lifecycle of not only resource exploration, but also resource modeling.

  16. Infrared spectral identification of metasomatic alteration minerals and its implication to gold exploration in Shihu Gold Deposit, Hebei Province, P.R. China

    NASA Astrophysics Data System (ADS)

    Liu, Jiacheng; Yao, Yuzeng; Wang, Yingpeng; Yuan, Zhou

    2014-11-01

    Hydrothermal alteration is of great importance for mineral exploration, especially the blind ore-hunting due to its larger scale and special zonation compared to the ore bodies. Infrared spectral identification of metasomatic alteration minerals can be done with little or no sample preparation and quantitative result can be obtained. In this paper, 65 wall-rock samples of several horizontal and vertical profiles were selected from Shihu Gold deposit in Hebei Province to do reflectance spectrum measurements by means of rough surface, smooth section and powder with portable ASD FieldSpec®3 spectrometer. ViewspecPro software was used to preprocess the spectrum, and metasomatic alteration minerals were spectrally discriminated by SII (Spectral International Inc) Specmin software package with wavelength of 1100~2500nm. The results shows that: (1) among all the three spectral libraries embedded in SPECMIN software, i.e., ASD, USGS and JPL, ASD spectral library is more suitable for the spectral hydrothermal alteration minerals identification in Shihu Gold Deposit; (2) the observed mineral zonation from wall-rock gneiss to ore-body indicates obvious downtrend of amphibole, chlorite, sericite, carbonate and barite, which is consistent with the microscopic and XRD results; (3) spectral identification of metasomatic alteration minerals is theoretically feasible, which is economic and convenient, and most important of all, the result can be quantitative or semi-quantitative. The results are helpful and successfully applied to the further mineral exploration in Shihu Gold Deposit.

  17. Tempo of magma degassing and the genesis of porphyry copper deposits

    PubMed Central

    Chelle-Michou, Cyril; Rottier, Bertrand; Caricchi, Luca; Simpson, Guy

    2017-01-01

    Porphyry deposits are copper-rich orebodies formed by precipitation of metal sulphides from hydrothermal fluids released from magmatic intrusions that cooled at depth within the Earth’s crust. Finding new porphyry deposits is essential because they are our largest source of copper and they also contain other strategic metals including gold and molybdenum. However, the discovery of giant porphyry deposits is hindered by a lack of understanding of the factors governing their size. Here, we use thermal modelling and statistical simulations to quantify the tempo and the chemistry of fluids released from cooling magmatic systems. We confirm that typical arc magmas produce fluids similar in composition to those that form porphyry deposits and conclude that the volume and duration of magmatic activity exert a first order control on the endowment (total mass of deposited copper) of economic porphyry copper deposits. Therefore, initial magma enrichment in copper and sulphur, although adding to the metallogenic potential, is not necessary to form a giant deposit. Our results link the respective durations of magmatic and hydrothermal activity from well-known large to supergiant deposits to their metal endowment. This novel approach can readily be implemented as an additional exploration tool that can help assess the economic potential of magmatic-hydrothermal systems. PMID:28079160

  18. Three-dimensional morphological analysis method for geologic bodies and its parallel implementation

    NASA Astrophysics Data System (ADS)

    Mao, Xiancheng; Zhang, Bin; Deng, Hao; Zou, Yanhong; Chen, Jin

    2016-11-01

    It has been found that the spatial locations and distributions of orebodies, especially for certain hydrothermal mineral deposits, are closely related to the shape of intrusive geologic bodies. For complex and large-scale geologic bodies, however, it is challenging to achieve rigorous and quantitative morphological analysis by standard geological surface reconstruction and trend-surface analysis methods. This paper presents a novel, quantitative morphological analysis method for general geologic bodies of closed 2-manifold surface based on mathematical morphology. Through the processes of morphological filtering, set operations and three-dimensional Euclidean distance transform (3D-EDT), the global trend shape, local convex and concave zones as well as degree of surface undulation of a geologic body are extracted respectively. All of the three analysis phases are speeded up via parallel algorithms implemented by using the message passing interface (MPI) standard. The proposed method is tested with a case study of the Xinwuli intrusion with complex shape in Fenghuangshan deposit of the Tongling district, China. The results demonstrate that the method is an effective and efficient way to achieve quantitative morphological analysis, thereby decreasing the time necessary to find the association between morphological parameters of geologic bodies and mineralization.

  19. Clay mineralogical evolution as a function of acidic leaching conditions: implications for alteration pathways on Mars' surface

    NASA Astrophysics Data System (ADS)

    Mavris, Christian; Cuadros, Javier; Nieto, Jose Miguel; Bishop, Janice; Vega, Raquel; Michalski, Joe

    2015-04-01

    Combined satellite and in-situ measurements of Mars surface have detected mineral assemblages suggesting processes for which Earth analogues exist. One of these cases is represented by aluminous clay-sulphate assemblages, which suggest alteration by acidic fluids. The Riotinto mining district (SW Spain) provides an Earth analogue for such Martian processes. The parent rocks belong to an Upper Palaeozoic (Late Famennian-Tournaisian) volcano-sedimentary complex including siliciclastic sediments and mafic and felsic volcanics, all of which underwent hydrothermal alteration.The oxidation of an extensive pyrite-rich orebody provided extreme to mild acidic fluxes that leached the surrounding rocks for over 20 million years (1). Samples from several locations in the Riotinto area show a range of clay products: vermiculite, smectite, possibly halloysite, and kaolinite with a wide range of crystal order. Jarosite and iron oxides appear in the most intensely leached areas. The different alteration products are due to the nature of the original rocks and the conditions in which low-pH leaching took place. Both mineral assemblages and spectral features of clay minerals from Riotinto can be used to interpret acidic alteration on Mars' surface. (1) Essalhi et al., 2011. Mineralium Deposita 46, 981-999.

  20. Clay minerals on Mars: Riotinto mining district (Huelva, Spain) as Earth analogue for acidic alteration pathways

    NASA Astrophysics Data System (ADS)

    Mavris, C.; Cuadros, J.; Bishop, J. L.; Nieto, J. M.; Michalski, J. R.

    2015-12-01

    Combined satellite and in-situ measurements of Mars surface have detected mineral assemblages indicating processes for which Earth analogues exist. Among them, aluminous clay-sulfate assemblages have been observed, which suggest alteration by acidic fluids. The Riotinto mining district (SW Spain) provides an Earth analogue site for such Martian processes. The parent rocks belong to an Upper Palaeozoic (Late Famennian-Tournaisian) volcano-sedimentary complex including siliciclastic sediments and mafic and felsic volcanics, all of which underwent hydrothermal alteration. The oxidation of an extensive pyrite-rich orebody provided mild to extreme acidic fluxes that leached the surrounding rocks for over 20 million years. The mineral assemblages are strongly dependent on their acidic alteration intensity. The observed mineralogical parageneses and leaching conditions for our sites at Riotinto are consistent with three alteration sequences: i) Mild: containing a range of clay minerals from vermiculite to kaolinite, with a wide variety of crystal order and mixed-layering; ii) Intermediate: containing smectite to kaolinite with jarosite-group phases; iii) Advanced: containing kaolinite, jarosite-group phases, and iron oxides. Our findings suggest that, even within this general scheme, the specific alteration pathways can be different.

  1. Preliminary investigation of the elemental variation and diagenesis of a tabular uranium deposit, La Sal Mine, San Juan County, Utah

    USGS Publications Warehouse

    Brooks, Robert A.; Campbell, John A.

    1976-01-01

    Ore in the La Sal mine, San Juan County, Utah, occurs as a typical tabular-type uranium deposit of the-Colorado Plateau. Uranium-vanadium occurs in the Salt Wash Member of the Jurassic Morrison Formation. Chemical and petrographic analyses were used to determine elemental variation and diagenetic aspects across the orebody. Vanadium is concentrated in the dark clay matrix, which constitutes visible ore. Uranium content is greater above the vanadium zone. Calcium, carbonate carbon, and lead show greater than fifty-fold increase across the ore zone, whereas copper and organic carbon show only a several-fold increase. Large molybdenum concentrations are present in and above the tabular layer, and large selenium concentrations occur below the uranium zone within the richest vanadium zone. Iron is enriched in the vanadium horizon. Chromium is depleted from above the ore and strongly enriched below. Elements that vary directly with the vanadium content include magnesium, iron, selenium, zirconium, strontium, titanium, lead, boron, yttrium, and scandium. The diagenetic sequence is as follows: (1) formation of secondary quartz overgrowths as cement; (2) infilling and lining of remaining pores with amber opaline material; (3) formation of vanadium-rich clay matrix, which has replaced overgrowths as well as quartz grains; (4) replacement of overgrowths and detrital grains by calcite; (5) infilling of pores with barite and the introduction of pyrite and marcasite.

  2. Iron isotope and REE+Y composition of the Cauê banded iron formation and related iron ores of the Quadrilátero Ferrífero, Brazil

    NASA Astrophysics Data System (ADS)

    Mendes, Mônica; Lobato, Lydia M.; Kunzmann, Marcus; Halverson, Galen P.; Rosière, Carlos A.

    2016-04-01

    The Minas Supergroup banded iron formations (BIFs) of the Brazilian Quadrilátero Ferrífero (QF) mineral province experienced multiple deformational events synchronous with hypogene mineralization, which resulted in the metamorphism of BIFs to itabirites and their upgrade to high-grade iron ore. Here, we present rare earth element and yttrium (REE+Y) compositions together with iron isotope ratios of itabirites and their host iron orebodies from 10 iron deposits to constrain environmental conditions during BIF deposition and the effects of hypogene iron enrichment. The REE+Y characteristics of itabirites (positive Eu anomaly and LREE depletion) indicate hydrothermal iron contribution to the Minas basin. Iron isotope data and Ce anomalies suggest BIFs were precipitated by a combination of anoxic biological-mediated ferrous iron oxidation and abiotic oxidation in an environment with free oxygen (such as an oxygen oasis), perhaps related to increase in oxygen concentrations before the Great Oxidation Event (GOE). The similarity of the REE+Y composition of the itabirites from the different QF deformational domains, as well as to other Superior-type BIFs, indicates that the metamorphism and synchronous hydrothermal mineralization did not significantly affect the geochemical signature of the original BIFs. However, iron isotope compositions of iron ore vary systematically between deformational domains of the QF, likely reflecting the specific mineralization features in each domain.

  3. Detailed mineralogy and petrology of manganese oxyhydroxide deposits of the Imini district (Morocco)

    NASA Astrophysics Data System (ADS)

    Dekoninck, A.; Bernard, A.; Barbarand, J.; Saint-Bezar, B.; Missenard, Y.; Lepretre, R.; Saddiqi, O.; Yans, J.

    2016-01-01

    Manganese ore in the Cenomanian-Turonian dolostone of the Imini district (south of the High Atlas, Morocco) displays a high Mn content due to the occurrence of pyrolusite, cryptomelane, hollandite sensu stricto, coronadite, romanechite, and lithiophorite. The orebodies occur mainly as three stratabound layers along the ~25-km-long ore belt following a WSW-ENE direction. Using scanning electron microscopy (SEM-EDS) coupled with X-ray diffraction (XRD), we here refine the mineralogy and petrology of Mn oxides and oxyhydroxides in order to constrain the paragenetic sequence and define the main processes of ore formation. Deposition and concentration of Mn oxyhydroxides follow a two-step sequence after dolomitization: (1) replacement of dolomite fabric (dolomite micrite and dolomite rhombs) by hollandite group minerals leading to a textural conservation and then (2) neoformation of collomorphous aggregates in an opened and brecciated system. These observations are consistent with a multistage evolution including multiple reworking and brecciation. Pyrolusite is the main Mn oxide observed in the Imini district during both early and late stages. The superficial environment provides supergene conditions suitable for the deposition of only Mn oxyhydroxides. This supergene environment and the occurrence of multiple bands of hollandite group minerals indicate an external migration (allochthonous supply) of Mn and associated elements, contemporaneous to an in situ chemical and mechanical dissolution of the host dolostone. The lithological heterogeneities of dolostone and its chemical environment compared to less permeable surrounding rocks may have provided the conditions to concentrate Mn oxides and oxyhydroxides.

  4. U-Pb dating of uranium deposits in collapse breccia pipes of the Grand Canyon region

    USGS Publications Warehouse

    Ludwig, K. R.; Simmons, K.R.

    1992-01-01

    Two major periods of uranium mineralization are indicated by U-Pb isotope dating of uranium ores from collapse breccia pipes in the Grand Canyon region, northern Arizona. The Hack 2 and 3, Kanab North, and EZ 1 and 2 orebodies apparently formed in the interval of 200 ?? 20 Ma, similar to ages inferred for strata-bound, Late Triassic-hosted uranium deposits in southern Utah and northern Arizona. Samples from the Grand Canyon and Pine Nut pipes, however, indicate a distinctly older age of about 260 Ma. The clustering in ages for a variety of uranium deposits at about the age of the lower part of the Chinle Formation (Late Triassic) suggests that uranium in these deposits may have been derived by leaching from volcanic ash in the Chinle and mobilized by ground-water movement. Pb isotope ratios of galenas in mineralized pipes are more radiogenic than those of sulfides from either uranium-poor pipes or occurrences away from pipes. Fluids which passed through the pipes had interacted with the Proterozoic basement, possibly through the vertical fractures which influenced the location and evolution of the pipes themselves. -from Authors

  5. Legacies of Glacio-fluvial Interactions in the Finger Lakes, Central New York

    NASA Astrophysics Data System (ADS)

    Safran, E. B.; Fountain, A. G.

    2011-12-01

    The Finger Lakes region of central New York exhibits spectacular examples of the interplay between glacial and fluvial processes. The Finger Lakes themselves were carved by ice sheets and related subglacial hydrologic processes that enlarged, over-deepened, and reversed the drainage direction of pre-existing fluvial valleys. The region's famous gorges flank the glacial troughs and reflect ongoing fluvial adjustment to glacially driven base level variations. Modern tools of topographic analysis permit quantification of the imprint that glacial processes leave on fluvial form and process. Regionally, ice sheet erosion is maximized along the north end of the Seneca/Cayuga trough. Local relief ranges from ~100 m at the north end of Seneca and Cayuga lakes to 250-400 m on the southern ends of these lakes and on the smaller, flanking lakes (Keuka, Canandaigua, Skaneateles, Owasco). Concavity indices for lake-tributary stream profiles are predominantly in the range of -7 to 0, reflecting a convex initial form imposed by glacial processes, while normalized channel steepness (ksn) indices are generally under 40 (reference concavity of 0.45), reflecting the gentle gradients of the glacial uplands. Concavity index and ksn values are maximized (>0, and >75, respectively) along short segments at the downstream ends of the so-called interglacial or post-glacial gorge reaches, again maximized at the southern and peripheral parts of the Seneca/Cayuga trough. Finally, streams that cross former channel courses buried by subglacial debris typically have more numerous and/or more pronounced knickpoints and more concave long profile segments than streams that do not. In short, the legacy of glaciations from the regional to the reach scale appears to be driving patterns of fluvial response in the Finger Lakes.

  6. Geothermal assessment of the MX deployment area in Nevada. Final report, April 1, 1981-April 30, 1982

    SciTech Connect

    Trexler, D.T.; Bruce, J.L.; Cates, D.; Dolan, H.H.; Covington, C.H.

    1982-06-01

    A preliminary geothermal resource assessment of the MX deployment area in Nevada focused on Coyote Spring Valley in southeastern Nevada. Initially, an extensive literature search was conducted and a bibliography consisting of 750 entries was compiled covering all aspects of geology pertaining to the study area. A structural study indicates that Coyote Spring Valley lies in a tectonically active area which is favorable for the discovery of geothermal resources. Hot water may be funneled to the near-surface along an extensive fracture and fault system which appears to underlie the valley, according to information gathered during the literature search and aerial photo survey. A total of 101 shallow temperature probes were emplanted in Coyote Spring Valley. Three anomalous temperature points all lying within the same vicinity were identified in the north-central portion of the valley near a fault. A soil-mercury study also identified one zone of anomalous mercury concentrations around the north end of the Arrow Canyon Range. A literature search covering regional fluid geochemistry indicated that the three fluid samples taken from Coyote Spring Valley have a higher concentration of Na + K. During field work, seven fluid samples were collected in Coyote Spring Valley which also appear to be derived from volcanic units due to the presence of Ca-Mg or Na-K carbonate-bicarbonate. A temperature gradient study of six test water wells indicates that only one geothermal well with a temperature of 35.5/sup 0/C (96/sup 0/F) exists in the central portion of the valley at the north end of Arrow Canyon Range near the zone of anomalous soil-mercury points. A cultural assessment of Coyote Spring Valley was performed prior to field work.

  7. Electrical Properties of Reacted Iron Cores Extracted From a Permeable Reactive Barrier Installation

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Slater, L.; Korte, N.

    2005-12-01

    We conducted experiments to investigate the application of non-invasive electrical method for monitoring iron corrosion and mineral precipitation processes on angle cores recovered from the Kansas City Plant reactive iron barrier. Electrical measurements showed continuous changes from the soil/iron interface into the barrier for all three cores. Scanning electron microscopy (SEM) identified iron surface alteration with thickest corrosion rind, indicating most severe corrosion, occurred close to upgradient soil/iron interface relative to locations further into the cores. Nitrogen adsorption measurements showed decreases in specific surface area of iron minerals from upgradient soil/iron interface into the barrier. X-ray diffractometry (XRD) identified precipitation of iron oxide/hydroxide, carbonate minerals, iron sulfide as well as green rusts in all three cores, and magnetite was identified as the dominant phase. Electrical measurements correlated well with solid phase analysis and illustrated the sensitivity of low frequency electrical method to iron corrosion and mineral precipitation processes. Electrical signature changes are attributed to (1) higher complex interfacial conductivity due to increased surface area and mineralogical alteration, and (2) increased electronic conduction due to enhanced electron transfer across the iron-fluid interface facilitated by mineralogical alternation and increased specific surface area during iron corrosion and mineral precipitation. Electrical measurements along with solid phase analysis also revealed more severe corrosion occurred at north end relative to south end of the barrier correlated with more groundwater flow through north end of the barrier. Our results on field cores are consistent with laboratory studies on synthetic iron columns presented previously and demonstrate that electrical measurements are a proxy indicator of Fe0 surface alteration and could be implemented for field barrier corrosion process monitoring.

  8. Geomorphic evolution of Montezuma wetlands, central New York State: A subglacial drainage network

    SciTech Connect

    Petruccione, J.L.; Mullins, H.T.; Wellner, R.W. . Dept. of Geology)

    1992-01-01

    Analysis of [approximately]12 km of on-land, multichannel seismic reflection data acquired from Montezuma Wetlands of Central New York State, in conjunction with water- and gas-well data, suggest that subglacial meltwaters may have played an important role in the geomorphic evolution of this large wetland. The wetlands (125 m[sup 2]) display a southward-directed surficial drainage pattern which terminates at the north end of Cayuga Lake. Bedrock extends as much as 56 m beneath the wetlands and has an undulatory, southward slope before rising over a sill at the north end of Cayuga Lake. The authors suggest that the incision of this southward-directed channel system into late Quaternary sediments and Paleozoic bedrock occurred via high-velocity meltwaters beneath the southern margin of the Laurentide ice sheet. Reflection data acquired from northern Cayuga Lake reveal a wedge of sediment which may have been eroded from the Montezuma channels. Morphostratigraphic relationships suggest that channel excavation and drumlin development were contemporaneous during a late stage glacial surge. Ice sheet recession caused a drainage reversal to the north and the creation of large proglacial lakes which flooded the Montezuma channels. fine-grained, glaciolacustrine sediments subsequently infilled these meltwater channels. Modern underfit, northward-directed drainage through the wetlands bears little resemblance to the southward-directed subglacial meltwaters that appear to have formed the Montezuma channels during deglaciation of the Laurentide ice sheet. These data and interpretations add to the growing list of evidence for significant subglacial meltwater discharge from beneath the southern margin of the Laurentide ice sheet during the last deglaciation.

  9. Nest fate and productivity of American Oystercatchers, Cumberland Island National Seashore, Georgia

    USGS Publications Warehouse

    Sabine, J.B.; Schweitzer, Sara H.; Meyers, J.M.

    2006-01-01

    The American Oystercatcher (Haematopus palliatus) is listed as a species of high priority by the U.S. Shorebird Conservation Plan and is state-listed as rare in Georgia; however, biologists have not focused on identifying the causes of egg and hatchling losses. In 2003 and 2004, continuous video monitoring was used to document reproductive success of American Oystercatchers and identify causes of nest failure at Cumberland Island National Seashore, Georgia. The modified Mayfield method and program CONTRAST were used to determine and compare survival of eggs and nestlings. Eleven pairs made 32 nest attempts during two seasons. Nine attempts were successful, fledging 15 chicks. Daily survival of clutches was 0.973 (95% CI = 0.960-0.987) for 2003, 0.985 (95% CI = 0.974-0.995) for 2004, and 0.979 (95% CI = 0.970-0.987) for combined years. Daily survival was greater on the North End, than on the South End of the island (X21 = 7.211, P = 0.007). Eighteen of 20 nest failures during the egg stage and one of eight chick losses were documented. Egg predators included raccoon (Procyon lotor, N = 9), bobcat (Lynx rufus, N = 3), and American Crow (Corvus brachyrhynchos, N = 1). A ghost crab (Ocypode quadata) preyed on one chick. Other causes of nest failure were tidal overwash (N = 1), horse trampling (N = 1), abandonment (N = 2), and human destruction (N = 1). The North End of the island has one of the highest reproductive rates reported along the Atlantic coast. Predator control may be an effective means of increasing reproductive success on the South End of the island.

  10. Sedimentation and subsidence patterns in the central and north basins of Lake Baikal from seismic stratigraphy

    USGS Publications Warehouse

    Moore, T.C.; Klitgord, Kim D.; Golmshtok, A.J.; Weber, E.

    1997-01-01

    Comparison of sedimentation patterns, basement subsidence, and faulting histories in the north and central basins of Lake Baikal aids in developing an interbasinal seismic stratigraphy that reveals the early synrift evolution of the central portion of the Baikal rift, a major continental rift system. Although there is evidence that the central and northern rift basins evolved at approximately the same time, their sedimentation histories are markedly different. Primary sediment sources for the initial rift phase were from the east flank of the rift; two major deltas developed adjacent to the central basin: the Selenga delta at the south end and the Barguzin delta at the north end. The Barguzin River system, located at the accommodation zone between the central and north basins, also fed into the southern part of the north basin and facilitated the stratigraphic linkage of the two basins. A shift in the regional tectonic environment in the mid Pliocene(?) created a second rift phase distinguished by more rapid subsidence and sediment accumulation in the north basin and by increased subsidence and extensive faulting in the central basin. The Barguzin delta ceased formation and parts of the old delta system were isolated within the north basin and on Academic Ridge. These isolated deltaic deposits provide a model for the development of hydrocarbon plays within ancient rift systems. In this second tectonic phase, the dominant sediment fill in the deeper and more rapidly subsiding north basin shifted from the flexural (eastern) margin to axial transport from the Upper Angara River at the north end of the basin.

  11. Lode-gold mineralization in the Tanami region, northern Australia

    NASA Astrophysics Data System (ADS)

    Huston, David L.; Vandenberg, Leon; Wygralak, Andrew S.; Mernagh, Terrence P.; Bagas, Leon; Crispe, Andrew; Lambeck, Alexis; Cross, Andrew; Fraser, Geoff; Williams, Nick; Worden, Kurt; Meixner, Tony; Goleby, Bruce; Jones, Leonie; Lyons, Pat; Maidment, David

    2007-01-01

    The Tanami region of northern Australia has emerged over the last two decades as the largest gold-producing region in the Northern Territory. Gold is hosted by epigenetic quartz veins in sedimentary and mafic rocks, and by sulfide-rich replacement zones within iron formation. Although limited, geochronological data suggest that most mineralization occurred at about 1,805-1,790 Ma, during a period of extensive granite intrusion, although structural relationships suggest that some deposits predate this period. There are three main goldfields in the Tanami region: the Dead Bullock Soak goldfield, which hosts the world-class Callie deposit; The Granites goldfield; and the Tanami goldfield. In the Dead Bullock Soak goldfield, deposits are hosted by carbonaceous siltstone and iron formation where a late (D5) structural corridor intersects an early F1 anticlinorium. In The Granites goldfield, deposits are hosted by highly sheared iron formation and are interpreted to predate D5. The Tanami goldfield consists of a large number of small, mostly basalt-hosted deposits that probably formed at a high structural level during D5. The D5 structures that host most deposits formed in a convergent structural regime with σ 1 oriented between E-W and ENE-WSW. Structures active during D5 include NE-trending oblique thrust (dextral) faults and ESE-trending (sinistral) faults that curve into N- to NNW-trending reverse faults localized in supracrustal belts between and around granite complexes. Granite intrusions also locally perturbed the stress field, possibly localizing structures and deposits. Forward modeling and preliminary interpretations of reflection seismic data indicate that all faults extend into the mid-crust. In areas characterized by the N- to NW-trending faults, orebodies also tend to be N- to NW-trending, localized in dilational jogs or in fractured, competent rock units. In areas characterized by ESE-trending faults, the orebodies and veins tend to strike broadly east

  12. Silver-rich telluride mineralization at Mount Charlotte and Au-Ag zonation in the giant Golden Mile deposit, Kalgoorlie, Western Australia

    NASA Astrophysics Data System (ADS)

    Mueller, Andreas G.; Muhling, Janet R.

    2013-03-01

    The gold deposits at Kalgoorlie in the 2.7-Ga Eastern Goldfields Province of the Yilgarn Craton, Western Australia, occur adjacent to the D2 Golden Mile Fault over a strike of 8 km within a district-scale zone marked by porphyry dykes and chloritic alteration. The late Golden Pike Fault separates the older (D2) shear zone system of the Golden Mile (1,500 t Au) in the southeast from the younger (D4) quartz vein stockworks at Mt Charlotte (126 t Au) in the northwest. Both deposits occur in the Golden Mile Dolerite sill and display inner sericite-ankerite alteration and early-stage gold-pyrite mineralization replacing the wall rocks. Late-stage tellurides account for 20 % of the total gold in the first, but for <1 % in the second deposit. In the Golden Mile, the main telluride assemblage is coloradoite + native gold (898-972 fine) + calaverite + petzite ± krennerite. Telluride-rich ore (>30 g/t Au) is characterized by Au/Ag = 2.54 and As/Sb = 2.6-30, the latter ratio caused by arsenical pyrite. Golden Mile-type D2 lodes occur northwest of the Golden Pike Fault, but the Hidden Secret orebody, the only telluride bonanza mined (10,815 t at 44 g/t Au), was unusually rich in silver (Au/Ag = 0.12-0.35) due to abundant hessite. We describe another array of silver-rich D2 shear zones which are part of the Golden Mile Fault exposed on the Mt Charlotte mine 22 level. They are filled with crack-seal and pinch-and-swell quartz-carbonate veins and are surrounded by early-stage pyrite + pyrrhotite disseminated in a sericite-ankerite zone more than 6 m wide. Gold grade (0.5-0.8 g/t) varies little across the zone, but Au/Ag (0.37-2.40) and As/Sb (1.54-13.9) increase away from the veins. Late-stage telluride mineralization (23 g/t Au) sampled in one vein has a much lower Au/Ag (0.13) and As/Sb (0.48) and comprises scheelite, pyrite, native gold (830-854 fine), hessite, and minor pyrrhotite, altaite, bournonite, and boulangerite. Assuming 250-300 °C, gold-hessite compositions

  13. Zonation of primary haloes of Atud auriferous quartz vein deposit, Central Eastern Desert of Egypt: A potential exploration model targeting for hidden mesothermal gold deposits

    NASA Astrophysics Data System (ADS)

    Harraz, Hassan Z.; Hamdy, Mohamed M.

    2015-01-01

    The Atud gold mine located in the Neoproterozoic diorite and metagabbro of the Central Eastern Desert of Egypt has been initially excavated during Pharaonic times. Between 1953 and 1969, the Egyptian Geological Survey and Mining Authority performed underground prospection in the auriferous quartz vein and metasomatic alteration zones in the main Atud area, estimating a principal gold lode of 19,000 tones (16.28 g/ton), and 1600 tons of damp (1.24 g/ton). Yet the potentiality of the deposit has not been exhausted. However, for exploration of hidden ore, quantitative characterization using trace elements zoning of mineralization haloes with 280 samples from surface and three underground mining levels is applied. This was through multivariate statistical analysis (Factor analysis) of 11 selected trace elements. Axial (vertical) extents of primary haloes above and beneath gently dipping orebody are also visualized to interpret the level of erosion, determine the direction of mineralizing solutions as well as to examine whether the hidden orebody is promising at the Atud mine. Axial zones of primary dispersion aureoles of trace elements are: Ag, As, S and U around the auriferous quartz veins; Cu, and Pb in the surface horizons; and Zn, Ni, Co, and U along the lower margin of mineralization zone. Gold contents in bedrock and quartz vein samples from level-42M are the highest (5.7 and 40.3 ppm, respectively). In the transverse (lateral) direction, the maximum relative accumulation of Au and Zn occurs at the Northern Shaft; Pb, Cu, As, and U at the Main Shaft; and Ag, S, Co, and Ni at the Southern Shaft. The estimated axial zonation sequence of indicator elements using the variability index is Pb → Cu → Ag → Au → As → S → Ni → Co → U → Zn. According to this zonation, an index such as (Pb × Cu)D/(U × Zn)D can be a significant for predicting the Au potentiality at a particular depth. In addition, the Pb/U zonality index is an appropriate indicator for the

  14. Trace-element fingerprints of chromite, magnetite and sulfides from the 3.1 Ga ultramafic-mafic rocks of the Nuggihalli greenstone belt, Western Dharwar craton (India)

    NASA Astrophysics Data System (ADS)

    Mukherjee, Ria; Mondal, Sisir K.; González-Jiménez, José M.; Griffin, William L.; Pearson, Norman J.; O'Reilly, Suzanne Y.

    2015-06-01

    The 3.1 Ga Nuggihalli greenstone belt in the Western Dharwar craton is comprised of chromitite-bearing sill-like ultramafic-mafic rocks that are surrounded by metavolcanic schists (compositionally komatiitic to komatiitic basalts) and a suite of tonalite-trondhjemite-granodiorite gneissic rocks. The sill-like plutonic unit consists of a succession of serpentinite (after dunite)-peridotite-pyroxenite and gabbro with bands of titaniferous magnetite ore. The chromitite ore-bodies (length ≈30-500 m; width ≈2-15 m) are hosted by the serpentinite-peridotite unit. Unaltered chromites from massive chromitites (>80 % modal chromite) of the Byrapur and Bhaktarhalli chromite mines in the greenstone belt are characterized by high Cr# (100Cr/(Cr + Al)) of 78-86 and moderate Mg# (100 Mg/(Mg + Fe2+)) of 45-55. In situ trace-element analysis (LA-ICPMS) of unaltered chromites indicates that the parental magma of the chromitite ore-bodies was a komatiite lacking nickel-sulfide mineralization. In the Ga/Fe3+# versus Ti/Fe3+# diagram, the Byrapur chromites plot in the field of suprasubduction zone (SSZ) chromites while those from Bhaktarhalli lie in the MOR field. The above results corroborate our previous results based on major-element characteristics of the chromites, where the calculated parental melt of the Byrapur chromites was komatiitic to komatiitic basalt, and the Bhaktarhalli chromite was derived from Archean high-Mg basalt. The major-element chromite data hinted at the possibility of a SSZ environment existing in the Archean. Altered and compositionally zoned chromite grains in our study show a decrease in Ga, V, Co, Zn, Mn and enrichments of Ni and Ti in the ferritchromit rims. Trace-element heterogeneity in the altered chromites is attributed to serpentinization. The trace-element patterns of magnetite from the massive magnetite bands in the greenstone belt are similar to those from magmatic Fe-Ti-V-rich magnetite bands in layered intrusions, and magnetites from

  15. Relantionships between gold mineralization and granite - Discussion with the support of a pluridisciplinary study of the Passa Tres gold deposit (South Brazil)

    NASA Astrophysics Data System (ADS)

    Dressel, Bárbara; Chauvet, Alain; Trzaskos, Barbara; Biondi, Joao Carlos; Bruguier, Olivier; Monie, Patrick; Villanova, Sandro; Bazille, Jose

    2016-04-01

    The Passa Três Granite, located at East of the Paraná State is elongated following a NNE-SSW direction. This sienogranite is emplaced within metapelites of the meso to neoproterozoic Açungui Group, between the Morro Agudo and Lancinha transcurrent faults, comprising the N040°E trending Lancinha Transcurrent Fault System. Gold mineralization within the Passa Três Granite is constituted by huge quartz veins with sulfides, variable quantities of fluorite and carbonates, forming orebodies with different internal textures, including massive, banded, sheared and brecciated. Structural data indicate the existence of two major fault systems, one N-S and the other E-W, with dips of 15-45°W and 20-75°S, respectively. Both NS and EW systems are interpreted to be contemporaneous and conjugate. Normal motions are everywhere suspected and main mineralized veins are located at opening sites at these fault systems, such as pull-aparts. The structural model suggests that the normal motion can be initiated by shearing along a "guide" level, in which sulfides and clay minerals are concentrated. This configuration can be observed at several scales, such as field, hand samples and thin section. Mineralized veins mainly contain, in addition to the quartz of the gangue, sulphides (pyrite, chalcopyrite, galena, molybdenite), fluorite, chlorite, muscovite, sericite, and carbonate. The presence of sericite, kaolinite and chlorite indicate the occurrence of, at least, propylitic and phyllic-type alterations, both in core of the granite and best-expressed at the rim of quartz-rich orebodies. Gold occurs as native grains in core of the quartz veins, within fractures that affect pyrite and frequently exhibiting normal motions consistent with the one observed at larger scale and systematically associated with chalcopyrite and galena. Quartz veins are sometimes bordered by aplitic dike. Additionally, some of the veins can exhibit a very thin margin of adularia minerals that seems to

  16. Re-Os isotopic evidence for an enriched-mantle source for the Noril'sk-type, ore-bearing intrusions, Siberia

    USGS Publications Warehouse

    Walker, R.J.; Morgan, J.W.; Horan, M.F.; Czamanske, G.K.; Krogstad, E.J.; Fedorenko, V.A.; Kunilov, V.E.

    1994-01-01

    Magmatic Cu-Ni sulfide ores and spatially associated ultramafic and mafic rocks from the Noril'sk I, Talnakh, and Kharaelakh intrusions are examined for Re-Os isotopic systematics. Neodymium and lead isotopic data also are reported for the ultramafic and mafic rocks. The Re-Os data for most samples indicate closed-system behavior since the ca. 250 Ma igneous crystallization age of the intrusions. There are small but significant differences in the initial osmium isotopic compositions of samples from the three intrusions. Ores from the Noril'sk I intrusion have ??Os values that vary from +0.4 to +8.8, but average +5.8. Ores from the Talnakh intrusion have ??Os values that range from +6.7 to +8.2, averaging +7.7. Ores from the Kharaelakh intrusion have ??Os values that range from +7.8 to +12.9, with an average value of +10.4. The osmium isotopic compositions of the ore samples from the Main Kharaelakh orebody exhibit minimal overlap with those for the Noril'sk I and Talnakh intrusions, indicating that these Kharaelakh ores were derived from a more radiogenic source of osmium than the other ores. Combined osmium and lead data for major orebodies in the three intrusions plot in three distinct fields, indicating derivation of osmium and lead from at least three isotopically distinct sources. Some of the variation in lead isotopic compositions may be the result of minor lower-crustal contamination. However, in contrast to most other isotopic and trace element data, Os-Pb variations are generally inconsistent with significant crustal contamination or interaction with the subcontinental lithosphere. Thus, the osmium and lead isotopic compositions of these intrusions probably reflect quite closely the compositions of their mantle source, and suggest that these two isotope systems were insensitive to lithospheric interaction. Ultramafic and mafic rocks have osmium and lead isotopic compositions that range only slightly beyond the compositions of the ores. These rocks also

  17. Mg- and K-bearing borates and associated evaporites at Eagle Borax spring, Death Valley, California: A spectroscopic exploration

    USGS Publications Warehouse

    Crowley, J.K.

    1996-01-01

    Efflorescent crusts at the Eagle Borax spring in Death Valley, California, contain an array of rare Mg and K borate minerals, several of which are only known from one or two other localities. The Mg- and/or K-bearing borates include aristarainite, hydroboracite, kaliborite, mcallisterite, pinnoite, rivadavite, and santite. Ulexite and probertite also occur in the area, although their distribution is different from that of the Mg and K borates. Other evaporite minerals in the spring vicinity include halite, thenardite, eugsterite, gypsum-anhydrite, hexahydrite, and bloedite. Whereas the first five of these minerals are found throughout Death Valley, the last two Mg sulfates are more restricted in occurrence and are indicative of Mg-enriched ground water. Mineral associations observed at the Eagle Borax spring, and at many other borate deposits worldwide, can be explained by the chemical fractionation of borate-precipitating waters during the course of evaporative concentration. The Mg sulfate and Mg borate minerals in the Eagle Borax efflorescent crusts point to the fractionation of Ca by the operation of a chemical divide involving Ca carbonate and Na-Ca borate precipitation in the subsurface sediments. At many other borate mining localities, the occurrence of ulexite in both Na borate (borax-kernite) and Ca borate (ulexite-colemanite) deposits similarly reflects ulexite's coprecipitation with Ca carbonate at an early concentration stage. Such ulexite may perhaps be converted to colemanite by later reaction with the coexisting Ca carbonate - the latter providing the additional Ca2+ ions needed for the conversion. Mg and Ca-Mg borates are the expected late-stage concentration products of waters forming ulexite-colemanite deposits and are therefore most likely to occur in the marginal zones or nearby mud facies of ulexite-colemanite orebodies. Under some circumstances, Mg and Ca-Mg borates might provide a useful prospecting guide for ulexite-colemanite deposits

  18. The Sarylakh and Sentachan gold-antimony deposits, Sakha-Yakutia: A case of combined mesothermal gold-quartz and epithermal stibnite ores

    NASA Astrophysics Data System (ADS)

    Bortnikov, N. S.; Gamynin, G. N.; Vikent'eva, O. V.; Prokof'ev, V. Yu.; Prokop'ev, A. V.

    2010-10-01

    New mineralogical, thermobarometric, isotopic, and geochemical data provide evidence for long and complex formation history of the Sarylakh and Sentachan Au-Sb deposits conditioned by regional geodynamics and various types of ore mineralization, differing in age and source of ore matter combined in the same ore-localizing structural units. The deposits are situated in the Taryn metallogenic zone of the East Yakutian metallogenic belt in the central Verkhoyansk-Kolyma Fold Region. They are controlled by the regional Adycha-Taryn Fault Zone that separates the Kular-Nera Terrane and the western part of the Verkhoyansk Fold-Thrust Belt. The fault extends along the strike of the northwest-trending linear folds and is deep-rooted and repeatedly reactivated. The orebodies are mineralized crush zones accompanied by sulfidated (up to 100 m wide) quartz-sericite metasomatic rocks and replacing dickite-pyrophyllite alteration near stibnite veinlets. Two stages of low-sulfide gold-quartz and stibnite mineralization are distinguished. The formation conditions of the early milk white quartz in orebodies with stibnite mineralization at the Sarylakh and Sentachan deposits are similar: temperature interval 340-280°C, salt concentration in fluids 6.8-1.6 wt % NaCl equiv, fluid pressure 3430-1050 bar, and sodic bicarbonate fluid composition. The ranges of fluid salinity overlapped at both deposits. In the late regenerated quartz that attends stibnite mineralization, fluid inclusions contain an aqueous solution with salinity of 3.2 wt % NaCl equiv and are homogenized into liquid at 304-189°C. Syngenetic gas inclusions contain nitrogen 0.19 g/cm3 in density. The pressure of 300 bar is estimated at 189°C. The composition of the captured fluid is characterized as K-Ca bicarbonatesulfate. The sulfur isotopic composition has been analyzed in pyrite and arsenopyrite from ore and metasomatic zones, as well as in coarse-, medium-, and fine-grained stibnite varieties subjected to

  19. Genetic Pd, Pt, Au, Ag, and Rh mineralogy in Noril'sk sulfide ores

    NASA Astrophysics Data System (ADS)

    Spiridonov, E. M.; Kulagov, E. A.; Serova, A. A.; Kulikova, I. M.; Korotaeva, N. N.; Sereda, E. V.; Tushentsova, I. N.; Belyakov, S. N.; Zhukov, N. N.

    2015-09-01

    The undeformed ore-bearing intrusions of the Noril'sk ore field (NOF) cut through volcanic rocks of the Late Permian-Early Triassic trap association folded in brachysynclines. Due to the nonuniform load on the roof of intrusive bodies, most sulfide melts were squeezed, up to the tops of ore-bearing intrusions; readily fusible Ni-Fe-Cu sulfide melts were almost completely squeezed. In our opinion, not only one but two stages of mineralization developed at the Noril'sk deposits: (i) syntrap magmatic and (ii) epigenetic post-trap metamorphic-hydrothermal. All platinum-group minerals (PGM) and minerals of gold are metasomatic in the Noril'sk ores. They replaced sulfide solid solutions and exsolution structures. All types of PGM and Au minerals occur in the ores, varying in composition from pyrrhotite to chalcopyrite, talnakhite, mooihoekite, and rich in galena; they are localized in the inner and outer contact zones and differ only in the quantitative proportions of ore minerals. The aureoles of PGM and Au-Ag minerals are wider than the contours of sulfide bodies and coincide with halos of fluid impact on orebodies and adjacent host rocks. The pneumatolytic PGM and Au-Ag minerals are correlated in abundance with the dimensions of sulfide bodies. Their amounts are maximal in veins of late fusible ore composed of eutectic PbS ss and iss intergrowths, as well as at their contacts. The Pd and Pt contents in eutectic sulfide ores of NOF are the world's highest. In the process of noble-metal mineral formation, the fluids supply Pd, Pt, Au, As, Sb, Sn, Bi, and a part of Te, whereas Fe, Ni, Cu, Pb, Ag, Rh, a part of Te and Pd are leached from the replaced sulfide minerals. The pneumatolytic PGM of the early stage comprises Pd and Pt intermetallic compounds enriched in Au along with Pd-Pt-Fe-Ni-Cu-Sn-Pb(As) and (Pd,Pt,Au)(Sn,Sb,Bi,Te,As) solid solutions. Pneumatolytic PGM and Au minerals of the middle stage are products of solid-phase transformation and recrystallization of

  20. Microbanded manganese formations; protoliths in the Franciscan Complex, California

    USGS Publications Warehouse

    Huebner, J. Stephen; Flohr, Marta J.

    1990-01-01

    The Buckeye manganese deposit, 93 km southeast of San Francisco in the California Coast Ranges, preserves a geologic history that provides clues to the origin of numerous lenses of manganese carbonate, oxides, and silicates that occur with interbedded radiolarian chert and metashale of the Franciscan Complex. Compositionally and mineralogically laminated Mn-rich protoliths were deformed and dismembered, in a manner that mimics in smaller scale the deformation of the host complex, and then were incipiently metamorphosed at blueschistfacies conditions. Eight phases occur as almost monomineralic protoliths and mixtures: rhodochrosite, caryopilite, chlorite, gageite, taneyamalite, braunite, hausmannite, and laminated chert (quartz). Braunite, gageite, and some chlorite and caryopilite layers were deposited as gel-like materials; rhodochrosite, most caryopilite, and at least some hausmannite layers as lutites; and the chert as turbidites of radiolarian sand. Some gel-like materials are now preserved as transparent, sensibly isotropic relics of materials that fractured or shattered when deformed, creating curved surfaces. In contrast, the micrites flowed between the fragments of gel-like materials. The orebody and most of its constituent minerals have unusually Mn-rich compositions that are described by the system MnO-SiO2-O2-CO2-H2O. High values of Mn/Fe and U/Th, and low concentrations of Co, Cu, and Ni, distinguish the Buckeye deposit from many high-temperature hydrothermal deposits and hydrogenous or diagenetic manganese and ferromanganese nodules and pavements. This chemical signature suggests that ore deposition was related to fluids from the sediment column and seawater. Tungsten is associated exclusively with gageite, in concentrations as high as 80 parts per million. The source of the manganese is unknown; because basalts do not occur near the deposit, it was probably manganese leached from the sediment column by reducing solutions. Low concentrations of calcium

  1. Planning additional drilling campaign using two-space genetic algorithm: A game theoretical approach

    NASA Astrophysics Data System (ADS)

    Kumral, Mustafa; Ozer, Umit

    2013-03-01

    Grade and tonnage are the most important technical uncertainties in mining ventures because of the use of estimations/simulations, which are mostly generated from drill data. Open pit mines are planned and designed on the basis of the blocks representing the entire orebody. Each block has different estimation/simulation variance reflecting uncertainty to some extent. The estimation/simulation realizations are submitted to mine production scheduling process. However, the use of a block model with varying estimation/simulation variances will lead to serious risk in the scheduling. In the medium of multiple simulations, the dispersion variances of blocks can be thought to regard technical uncertainties. However, the dispersion variance cannot handle uncertainty associated with varying estimation/simulation variances of blocks. This paper proposes an approach that generates the configuration of the best additional drilling campaign to generate more homogenous estimation/simulation variances of blocks. In other words, the objective is to find the best drilling configuration in such a way as to minimize grade uncertainty under budget constraint. Uncertainty measure of the optimization process in this paper is interpolation variance, which considers data locations and grades. The problem is expressed as a minmax problem, which focuses on finding the best worst-case performance i.e., minimizing interpolation variance of the block generating maximum interpolation variance. Since the optimization model requires computing the interpolation variances of blocks being simulated/estimated in each iteration, the problem cannot be solved by standard optimization tools. This motivates to use two-space genetic algorithm (GA) approach to solve the problem. The technique has two spaces: feasible drill hole configuration with minimization of interpolation variance and drill hole simulations with maximization of interpolation variance. Two-space interacts to find a minmax solution

  2. Dynamic Triggering of Microseismicity inferred from Spatio/Temporal Patterns in a Mine Setting

    NASA Astrophysics Data System (ADS)

    Castellanos, F.; Van der Baan, M.

    2014-12-01

    We examine spatial and temporal patterns of microseismic events in an underground mine. Our objective is to address three key questions: Where does the seismicity occur? Why does it occur in these locations but not elsewhere? And what triggers it? We take advantage of waveform similarity by performing multiplet analysis based on the double-difference technique to obtain highly accurate relative locations. Seven vertical receiver boreholes that surround the area under investigation have recorded microseismic data during a month, thus providing a good azimuthal coverage. A minimum crosscorrelation level of 85% is used to detect 21 multiplet groups, which represents 60% of the total seismicity. The largest groups are located close to the main shaft and tunnels at orebody levels, thus we postulate seismicity is facilitated by the potential of subsidence if we assume a compacting earth and hoop stresses acting on the vertical shafts. Surprisingly, most events only occur during certain hours of the day but do not relate to blasting. They correlate with scheduled operations of rock removal. Therefore, it is likely they have been triggered by the transportation of the debris along the main shaft instead of blasting, as we initially expected. Given that seismicity is present around the main shaft but absent close to the second air shaft, we conclude that for seismicity to occur both a favourable stress state must exist, as well as additional external forces, causing dynamic triggering. This analysis provides more insight into anthropogenic processes and their roles as major initiators of seismicity during dynamic stress transfer thereby facilitating identification of hazardous areas in mine settings.

  3. Geochemical-exploration in the Coeur d'Alene District, Idaho and Montana

    USGS Publications Warehouse

    Gott, Garland Bayard; Cathrall, John B.

    1980-01-01

    The principal ore deposits in the Coeur d'Alene district are lead-zinc-silver replacement veins in Precambrian rocks of the Belt Supergroup. The main ore minerals are galena, tetrahedrite, and sphalerite. The host rocks are mainly quartzite, siltite, and argillite. Cretaceous quartz monzonite locally intrudes the Beltrocks. The geochemical investigations reported here were carried out to determine if geochemical methods would be useful in the search for concealed ore deposits. About 8,700 soil samples and 4,000 rock samples were collected from a 300-square-mile (780 square kilometer) area for this study. The samples were analyzed for 35 elements. Antimony, silver, lead, manganese, and copper form dispersion patterns and halos that are related to many of the ore deposits within the district, and these same elements were found to be most useful in delineating the known mineral belts that contain most of the orebodies. The dispersion patterns are probably primary, having only minor modifications due to secondary redistribution of the ore-forming elements. The mineral belts and geochemical-dispersion patterns have been laterally offset, perhaps as much as 16 miles (26 km), by postore faulting. Prefault dispersion patterns can be restored by adjusting the geochemical maps along the postore faults to match the dispersion patterns across the fault trace. The reconstructed dispersion patterns of antimony, arsenic, lead, sulfur, and the ratio of cadmium to zinc form concentric halos around the restored position of the Gem stocks. Most of the Coeur d'Alene ore has been mined from this halo. It appears that the geochemical exploration methods reported here successfully delineate the major mineral belts and indicate unexplored areas in which to search for new deposits.

  4. Geology and timing of mineralization at the Cangshang gold deposit, north-western Jiaodong Peninsula, China

    USGS Publications Warehouse

    Zhang, X.; Cawood, Peter A.; Wilde, S.A.; Liu, R.; Song, H.; Li, W.; Snee, L.W.

    2003-01-01

    The Cangshang gold deposit of the northwestern Jiaodong Peninsula contains reserves of greater than 50 tonnes (t) and is developed by the largest open pit gold mine in China. This deposit is a Jiaojia-style (i.e. disseminated-and-veinlet) deposit. It is controlled by the San-Cang fault zone, which trends ???040?? and dips 40-75??SE at the mine site. The main (no. 1) orebody lies between a hanging wall of Precambrian metamorphic rocks (mainly amphibolite) of the Fenzishan Group and a footwall composed of the Mesozoic Linglong granitoid. The ore zone is mainly composed of pyritized, sericitized and silicified granitoid, which has undergone variable degrees of cataclasis. SHRIMP U-Pb dating of zircon indicates that the protolith of the hanging wall amphibolite was formed at 2530 ?? 17 Ma and underwent metamorphism at 1852 ?? 37 Ma. The footwall granodiorite has been dated at 166 ?? 4 Ma, whereas zircons from the ore zone yield a younger age of 154 ?? 5 Ma. Cathodoluminescence images of zircons from the granodiorite and ore zone show oscillatory zonation indicative of an igneous origin for both and the ages of these zircons, therefore, are all interpreted to be representative of magmatic crystallization. Dating of sericite by 40Ar-39Ar has been used to directly determine the timing of formation of the Cangshang deposit, providing the first time absolute age on formation of the Jiaojia-style gold deposits. The well-defined age of 121.3 ?? 0.2 Ma provides the precise timing of gold mineralization at the Cangshang deposit. This age is consistent with those of Linglong-style (vein type) gold mineralization, also from the north-western Jiaodong Peninsula, at between 126 and 120 Ma. Therefore, our work indicates that both styles of gold deposits in the Jiaodong Peninsula were formed during the same mineralization event.

  5. Geology and mineral deposits of the Minnie Moore and Bullion mineralized areas, Blaine County, Idaho

    USGS Publications Warehouse

    Link, Paul Karl; Worl, Ronald G.

    2001-01-01

    In the early 1880?s the discovery of rich ores in the Minnie Moore and Bullion mineralized areas sparked a rush to settle and develop the Wood River valley. Silver and lead discoveries in these areas spurred the boom in mining after completion of the Oregon Short Line Railroad to Hailey in 1883. In both areas the ore comprises galena, sphalerite, and tetrahedrite in a gangue of siderite, calcite, or quartz. Minor goldbearing quartz veins are also present. The ore is in fissure and replacement veins along fracture systems that formed in Late Cretaceous time, after intrusion of nearby granodiorite or quartz diorite stocks. The ore formed under mesothermal conditions and heat was supplied by the nearby plutons. In the Minnie Moore area, the mineralized veins are cut by low-angle normal faults that are of probable Eocene age. In the Minnie Moore mineralized area, the host rock is the middle part of the Devonian Milligen Formation, (the informal Lucky Coin limestone and Triumph argillite), which is the same stratigraphic level as the host ore in the rich Triumph mine northeast of Hailey. In the Bullion mineralized area, the ore is hosted by the lower member of the Middle Pennsylvanian to Lower Permian Dollarhide Formation. Rich ore was mined in several tunnels that reached the Mayflower vein, a northwest-striking mineralized shear zone. The deposits are thought to be mainly mesothermal veins that formed in association with Cretaceous magmatism. The syngenetic stratiform model of ore formation has often been applied to these deposits, however, no evidence of syngenetic mineralization was found in this study. Faulting has displaced most of the major orebodies and thus has made mining these deposits a challenge.

  6. Characterization of novel archaeal lineages associated with acid mine drainage in Iron Mountain, CA using anaerobic cultivation and cultivation-independent genomic analysis

    NASA Astrophysics Data System (ADS)

    Baker, B. J.; Tyson, G. W.; Hugenholtz, P.; Banfield, J. F.

    2003-12-01

    Iron Mountain in northern California, contains a pyritic orebody undergoing dissolution from mining creating extremely acidic (generally ~pH 0.8), warm (>40° C), and highly concentrated metal solutions, referred to as acid mine drainage (AMD). AMD communities are limited in the number of lineages that have been associated with them. The archaeal members of the mine community, in the past, have been restricted to the Thermoplasmatales order. The various clades within the Thermoplasmatales have been named the "alphabet plasma" (ie. Aplasma through Gplasma). The majority of them remain uncultured. Anaerobic media containing ferric sulfate and glucose has been successful in enriching and maintaining members of the "alphabet plasmas". Analysis of aqueous chemistry of these cultures shows a reduction of ferric iron, suggesting a subset of these archaea are capable of iron reduction. This may be a relevant part of iron cycling in the mine previously overlooked. Recently, another deeply branched archaeal group, named WTF1102, has been identified. Completely independent of all previously identified AMD lineages, its closest relative available in present databases is to that of the euryarchaeota group referred to as VAL1, which consists entirely of uncultured and poorly represented in sequences. Screening of the community genomic library constructed from the site revealed a contiguous fragment from two shotgun clones, totaling ~4.4kb in length. These clones have been fully sequenced and contain two genes, a phosphatase and 16S rRNA. The 16S rRNA gene has a 515 bp long intron at 1102 (E. coli numbering) that contains an open reading frame which encodes for a ubitiquitin-like protein modifier. Phylogenetic analysis of the phosphotase amino acid sequence revealed it branches with that of other acidophiles, Thermoplasma and Ferroplasma. We are developing FISH probes to target the individual "alphabet plasma" and WTF1102. This work extends what we know about the diversity and

  7. Composition, distribution, and hydrologic effects of contaminated sediments resulting from the discharge of gold milling wastes to Whitewood Creek at Lead and Deadwood, South Dakota

    USGS Publications Warehouse

    Goddard, K.E.

    1989-01-01

    The Whitewood Creek-Belle Fourche-Cheyenne River stream system in western South Dakota has been extensively contaminated by the discharge to Whitewood Creek of about 100 million tons of mill tailings from gold-mining operations. The resulting contaminated sediments contain unusually large concentrations of arsenic, as much as 11,000 micrograms/g, derived from the mineral arsenopyrite, as well as potentially toxic constituents derived from the ore-body minerals or from the milling processes. Because of the anomalous arsenic concentrations associated with the contamination, arsenic was used as an indicator for a geochemically based, random, sediment-sampling program. Arsenic concentrations in shallow, contaminated sediments along the flood plains of the streams were from 1 to 3 orders of magnitude larger than arsenic concentrations in uncontaminated sediments in about 75% of the flood plains of Whitewood Creek and the Belle Fourche River. Appreciable surface-water contamination resulting from the contaminated sediments is confined to Whitewood Creek and a reach of the Belle Fourche River downstream from the mouth of Whitewood Creek. In Whitewood Creek , dissolved-arsenic concentrations vary from about 20 to 80 microgram/L during the year in response to variations in groundwater inflow and dilution, whereas total-recoverable-arsenic concentrations vary from about 20 to 8 ,000 micrograms/L during short periods in response to rapid changes in suspended-sediment concentration. Contamination of the alluvial aquifer along the stream system is limited to areas in direct contact with large deposits of contaminated sediments. Within the aquifer, arsenic concentrations are thought to be controlled by sorption-desorption on metallic hydroxides. (USGS)

  8. Geochronology of the western and central Brooks Range, Alaska: Implications for the geologic evolution of the Anarraaq and Red Dog Zn-Pb-Ag deposits

    USGS Publications Warehouse

    Rombach, C.S.; Layer, P.W.

    2004-01-01

    A compilation of published geochronology of rocks and minerals from the western and central Brooks Range provides a framework for understanding the complex history of the Brooks Range and northern Alaska. A simplified timeline of events comprises (1) Devonian extension, (2) Mississippian extension and Zn-Pb-Ag mineralization, (3) a passive interval, (4) pre-Brooks Range orogeny rock-formation and thermal event, (5) inception of Brooks Range orogeny, (6) exhumation and the end of main-stage deformation, and (7) subsequent episodic deformation. This compilation is supplemented by new 40Ar/39Ar dates of white mica from the Anarraaq and Red Dog Zn-Pb-Ag (+ barite) deposits from the western Brooks Range. The deposits are hosted in black shale and carbonate rocks of the Late Mississippian-Early Pennsylvanian Kuna Formation. Quartz-pyrite-white mica grains in sedimentary rocks above the Anarraaq deposit yield an age of 195.0 ?? 2.0 Ma, and paragenetically late quartz-pyrite-white mica from the Main orebody at the Red Dog deposit has an age of 126.1 ?? 0.7 Ma. These white micas are much younger than the age of Zn-Pb-Ag mineralization at Red Dog (338 ?? 5.8 Ma Re-Os age of pyrite). The date for white mica from Anarraaq (???195 Ma) appears to be related to a large-scale thermal event in the region immediately before the inception of the Brooks Range orogeny. The white mica from the Red Dog deposit (???126 Ma) correlates with the later stages of the orogeny, a period of blueschist metamorphism, extension, and rapid exhumation, which varied with geographic location. These dates suggest that the Red Dog deposits underwent significant hydrothermal overprinting during multiple episodes of the Brooks Range orogeny. ?? 2004 by Economic Geology.

  9. [sup 40]Ar/[sup 39]Ar isotopic dates from the Cripple Creek gold-Telluride district, Colorado: Constraints on the timing of magmatism and mineralization

    SciTech Connect

    Kelley, K.D.; Snee, L.W. ); Thompson, T.B. . Dept. of Earth Resources)

    1993-04-01

    The Cripple Creek district is within a Tertiary diatreme-intrusive complex, a steep-walled basin in Proterozoic pelitic and igneous rocks that is filled with terrigenous sedimentary rocks, volcanic and hydrothermal breccias, and tuffs. The orebodies occur as veins in Proterozoic and Tertiary rocks or as deposits localized within hydrothermal breccia bodies or disseminated in diatreme breccias. [sup 40]Ar/[sup 39]Ar dates from igneous rocks demonstrate the approximately contemporaneous emplacement of the most differentiated phonolitic rocks. Three sanidine samples from phonolite yield apparent ages ranging from 30.9 [+-] 0.1 to 31.8 [+-] 0.1 Ma (1 sigma). Biotite and sanidine age spectra from relatively less differentiated tephriphonolite are discordant; the emplacement age is estimated to be between 31.4 [+-] 0.1 and 32.5 [+-] 0.1 Ma. A maximum age of 31.5 [+-] 0.1 Ma was obtained on a whole-rock sample of trachyandesite. The mafic phonolitic rocks are relatively younger. A sample of the Isabella dike, a phonotephrite dike cutting phonolite, yields a whole-rock age of 28.7 [+-] 0.04 Ma. The data suggest that mineralization both predates and postdates emplacement of the mafic phonolitic rocks. Hydrothermal biotite in a vein cutting phonolite yields an age of 29.9 [+-] 0.1 Ma. The age spectrum of adularia from a vein cutting volcaniclastic rocks is difficult to interpret due to the presence of excess argon, but an age is estimated to be between 29.5 and 30.4 Ma. In the vicinity of the phonotephrite dike, field evidence suggests that vein mineralization postdates emplacement of the dike; potassium feldspar from potassium altered phonolite in the vicinity of mineralized rock yields ages of 28.2 [+-] 0.1 and 28.8 [+-] 0.1 Ma.

  10. The Niujiaotang Cd-rich zinc deposit, Duyun, Guizhou province, southwest China: ore genesis and mechanisms of cadmium concentration

    NASA Astrophysics Data System (ADS)

    Ye, Lin; Cook, Nigel J.; Liu, Tiegeng; Ciobanu, Cristiana L.; Gao, Wei; Yang, Yulong

    2012-08-01

    The Niujiaotang zinc deposit in southeastern Guizhou, China, is a Mississippi Valley-type Zn deposit within Early Cambrian carbonate rocks. Sphalerite is enriched in cadmium (average 1.4 wt.% Cd), which occurs mostly as isomorphous impurities in the sphalerite lattice. Discrete cadmium minerals (greenockite and otavite) are rare and are found almost exclusively in the oxidation zone of the deposit, probably formed as secondary minerals during weathering-leaching processes. Geochemical data show that the sulfides are enriched in heavy sulfur, with δ34S ranging from +10.0‰ to +32.8‰ (mean +22.5‰). The consistent Pb isotopic compositions in different sulfide minerals are similar to that of Cambrian strata. The ore lead probably came from U- and Th-rich upper crustal rocks, such as the Lower Cambrian Wuxun Formation. The ore fluid is of low-temperature (101°C to 142°C) type, with a Na-Ca-Mg-Cl-dominant composition, and is interpreted as oil-field brine. The data indicate that the metals were mainly derived from the Early Cambrian strata (Qingxudong and Wuxun Formations), whereas sulfur is sourced from sulfate in Cambrian strata or oil-field brines of the Majiang petroleum paleoreservoir. The genetic model for the deposit invokes an Early Cambrian shallow-sea environment on the Yangtze Platform. Zinc and Cd in seawater were concentrated in abundant algae via unknown biological mechanisms, resulting in large amounts of Zn- and Cd-rich algal ooliths. During the Ordovician, concurrent with destruction of the Majiang petroleum paleoreservoir, oil-field brines migrated from the center of the basin to the margin leaching metals from the Cambrian strata. In the Niujiaotang area, preexisting Zn and Cd, particularly in the Qingxudong and Wuxun Formation, were further mobilized by hot brines rising along the Zaolou fault system, forming stratiform and generally conformable Zn-Cd orebodies in reactive carbonate lithologies.

  11. Boron isotope systematics of tourmaline formation in the Sullivan Pb-Zn-Ag deposit, British Columbia, Canada

    USGS Publications Warehouse

    Jiang, S.-Y.; Palmer, M.R.; Slack, J.F.; Shaw, D.R.

    1999-01-01

    We report here the results of 54 boron isotope analyses of tourmaline associated with the giant Sullivan Pb-Zn-Ag deposit in southeastern British Columbia, Canada. The ??11B values range from -11.1 to -2.9???, which is almost as great as the range found worldwide in tourmalines from 33 massive sulfide deposits and tourmalinites in dominantly clastic metasedimentary terranes. The major control on the overall ??11B values of the Sullivan tourmalinites is the boron source. Potential controls over the large range of the data also include: (1) differences in formation temperatures of the tourmalinites, (2) different stages of tourmaline formation, (3) variations in the proportions of dissolved boron incorporated into the tourmaline (Rayleigh fractionation), (4) seawater entrainment, and (5) post-depositional metamorphism. The boron isotope data at Sullivan are consistent with boron derivation from leaching of footwall clastic sediments. However, the great abundance of tourmaline in the Sullivan deposit suggests that the local clastic sediments were not the sole source of boron, and we argue that non-marine evaporites, buried deep below the orebody, are the most viable source of this additional boron. It is likely that some of the variation in tourmaline ??11B values reflect mixing of boron from these two sources. Comparison of the potential effects of these controls with geologic and other geochemical evidence suggests that major causes for the wide range of ??11B values measured at Sullivan are seawater entrainment and Rayleigh fractionation, although in places, post-depositional alteration and thermal metamorphism were important in determining ??11B values of some of the recrystallized tourmalinites.

  12. Distribution of Platinum-Group Elements in Chromite Ores of the Sorkhband Ultramafic Complex, Kerman, Southeastern Iran

    NASA Astrophysics Data System (ADS)

    Najafzadeh, Alireza; Arvin, Mohsen; Ahmadipour, Hamid; Pan, Yuanming

    2016-10-01

    The Ordovician Sorkhband ultramafic complex lies in southern Kerman Province of Iran. The wedge shape complex covers an area of more than 100 km2 and is divided into: lower part comprises of dunites, largest podiform chromitite deposits in Iran (Faryab mine), olivine clinopyroxenite dykes and massive's, wehrlite and olivine websterite dykes; and upper part comprises of clinopyroxene bearing harzburgites, with subordinate lenses and dykes of dunite, massive and dyke like olivine clinopyroxenite and minor orthopyroxenite dykes with no significant chromitite mineralization. Chromitite orebodies exhibit variable sizes and shapes, forming pods, lenses, bands, vein-like bodies and rich dissemination. Podiform chromitites in dunite form tabular to lenticular bodies although may occur also as pencil-like masses. The chromitites occur in four distinct textural modes. Massive, disseminated, banded and nodular chromitites are the most common textural types and commonly grade into one other. Massive chromitites have sharp contacts with the enclosing dunite whereas disseminated bodies grade outward into dunite and occasionally pass into interbanded chromitite and dunite. A detailed electron microprobe study reveals very high Cr#, Mg# and very low TiO2 contents for chromian spinels in chromitites. The Sorkhband chromitites contain up to 440 ppb total PGE, and display a systematic enrichment in IPGE relative to PPGE, with a steep negative slope in the PGE spidergrams and very low PPGE/IPGE ratios, a feature typical of ophiolitic podiform chromitites worldwide. The mineral chemistry data and PGE geochemistry of the chromitites indicates that the Sorkhband ultramafic complex was generated from an arc-related magma with boninitic affinity in a supra-subduction zone setting.

  13. Iron-rich fragments in the Yamansu iron deposit, Xinjiang, NW China: Constraints on metallogenesis

    NASA Astrophysics Data System (ADS)

    Li, Hou-Min; Ding, Jian-Hua; Zhang, Zhao-Chong; Li, Li-Xing; Chen, Jing; Yao, Tong

    2015-12-01

    Volcanic rock-hosted iron deposits are among the important iron ores in China. However, the nature of primary magma and petrogenesis associated with these iron ores remains controversial. Here, we report iron-rich fragments (IRF) from the Yamansu iron deposit in Eastern Tianshan Mountains, NW China, which occurs in association with volcanic breccia, submarine volcanic breccia and ignimbrite. The IRF is composed of five types including oligoclase-iron oxide type (OIO), oligoclase-albite-iron oxide type (OAIO), albite-iron oxide type (AIO), albite-K-feldspar-iron oxide type (AKIO) and K-feldspar-iron oxide type (KIO). These fragments display typical volcanic fabric features, such as porphyritic texture, hyalopilitic texture of the groundmass and vesicles filled by minerals to form amygdales. The feldspar phenocrysts of IRF are dominantly albite. The groundmass of IRF consists of magnetite and feldspar. The magnetite is distributed in between the feldspar laths, and together display hyalopilitic texture which could be observed only in volcanic rocks. The vesicles are filled with magnetite, feldspar, chlorite and calcite from the margin to the interior. The IRF has high Si, Al, Fe, Ca, Ti, Na and K contents and low Mg content. The average total Fe is 26 wt.%. The magnetite is mostly titanium-vanadium magnetite, with the TiO2 content ranging up to 4.86 wt.% and V2O3 content up to 3.20 wt.%. The IRF probably came from iron-rich melts and represent the products of the Fenner magma evolution. The basaltic magma evolved into the Fe-Na-rich residual melts by crystallization under low oxygen fugacity condition in a closed magma chamber after intruding into the shallow crust. The Fe-Na-rich residual melts were emplaced in hypabyssal environments or erupted generating the orebodies or providing the material source for the generation of the high-grade iron ores which were subsequently enriched by the late-stage hydrothermal fluids.

  14. Comparison of the native antimony-bearing Paiting gold deposit, Guizhou Province, China, with Carlin-type gold deposits, Nevada, USA

    NASA Astrophysics Data System (ADS)

    Xie, Zhuo-Jun; Xia, Yong; Cline, Jean S.; Yan, Bao-Wen; Wang, Ze-Peng; Tan, Qin-Ping; Wei, Dong-Tian

    2017-01-01

    The Paiting gold deposit, Guizhou Province, China, has been regarded as a Carlin-type gold deposit by several researchers. Alteration and ore-related minerals from the Paiting deposit were examined, and results were compared with the Cortez Hills Carlin-type gold deposit, Nevada, USA. Similarities include the structural and stratigraphic controls on the orebodies in both deposits and the occurrence of invisible gold ionically bound in arsenian pyrite. Significant differences include the following: (1) The gold-bearing mineral in Nevada is arsenian pyrite. However, gold-bearing minerals in the Paiting deposit include arsenopyrite, arsenian pyrite, and trace pyrrhotite. Also, euhedral or subhedral gold-bearing arsenian pyrite at Paiting contains significantly less As, Cu, and Hg than gold-bearing pyrite from Nevada. (2) Alteration in the Paiting deposit displays significantly less decarbonatization. Instead, dolomite precipitation, which has not been described in Nevada deposits, is associated with deposition of gold-bearing sulfide minerals. (3) Stibnite and minor native antimony typify Paiting late-ore-stage minerals, whereas in Nevada, realgar, orpiment, and calcite are common late-ore-stage minerals. Precipitation of native antimony in the Paiting deposit reflects the evolution of a late-ore fluid with unusually low sulfur and oxygen fugacities. Some characteristics of the Paiting gold deposit, including formation of ore-stage dolomite and precipitation from CO2-rich ore fluids at temperatures in excess of 250 °C, are more typical of orogenic deposits than Nevada Carlin deposits. The presence of similarities in the Paiting deposit to both Carlin type and orogenic deposits is consistent with formation conditions intermediate to those typical of Carlin type and orogenic systems.

  15. Re-Os isotopic and trace element compositions of pyrite and origin of the Cretaceous Jinchang porphyry Cu-Au deposit, Heilongjiang Province, NE China

    NASA Astrophysics Data System (ADS)

    Zhang, Peng; Huang, Xiao-Wen; Cui, Bin; Wang, Bo-Chao; Yin, Yi-Fan; Wang, Jing-Rui

    2016-11-01

    The Jinchang Cu-Au deposit in Northeast China contains more than 76 tons of Au and 4683 tons of Cu with average ore grades of 11.34 g/t Au and 1.44% Cu. The deposit is typical of porphyry types and consists of gold orebodies mainly hosted in a ∼113 Ma granitic porphyry and breccia pipes within the porphyry intrusion. Mineralization is closely associated with early potassic alteration and late phyllic alteration. Pyrite is the main Au-bearing mineral and contains 1.48-18.9 ppb Re and 11.4-38 ppt common Os. Extremely low common Os concentrations and high Re/Os ratios are indicative of derivation of ore-forming materials from the crust. Low Re in pyrite from the Jinchang deposit may indicate a mixing source of mantle and crust or a crustal source. Five Re-Os isotopic analyses yield a model 1 isochron age of 114 ± 22 Ma (2σ, MSWD = 0.15), similar to the age of the host porphyry. Pyrite contains detectable Co, Ni, Cu, Zn, As, Ag, Au, Sb, Pb and Bi. Pyrite has Co/Ni ratios similar to that of volcanogenic and hydrothermal sulfide deposits, indicating a magmatic-hydrothermal origin, and has Au and As contents similar to that of porphyry-epithermal systems. Pyrite grains from potassic and phyllic alteration stages have different trace element contents, reflecting the evolution of ore-forming fluids from magmatic dominated to magmatic mixed with meteoric water. In combination with regional geology, our new results are suggestive of origin of the Jinchang Cu-Au deposit from contemporary intrusions of granitic porphyries related to the Early Cretaceous subduction of the Paleo-Pacific plate.

  16. External Sulfur Addition in the Generation of Sulfide-rich Ni-Cu-PGE Deposits: The Importance of Focused Magma Flow

    NASA Astrophysics Data System (ADS)

    Ripley, E. M.

    2015-12-01

    Sulfide-rich Ni-Cu-PGE orebodies hosted in mafic to ultramafic igneous rocks require focused magma flow and vigorous interaction with country rocks to liberate sulfide, as well as to produce traps for immiscible sulfide liquid. In the 1.1 Ga Midcontinent Rift System (MRS), Ni-rich sulfide deposits occur in conduit systems. Variations in S and Os isotope ratios indicate that magmas which followed different crustal pathways were focused into a central conduit that supplied overlying flows and sills. The 1.3 Ga Voisey's Bay deposit in Labrador represents sulfide liquid collection in a conduit system which includes dike-like bodies and larger sub-horizontal chambers. Variable d34S values again strongly suggest that focused magma flow and turbulence in the conduit resulted in the input of magmatic pulses that had undergone S isotopic homogenization even though pelitic country rocks are characterized by a range in S isotope values from -17 to +18 ‰. A very similar physical setting characterizes the sulfide-bearing Duke Island Complex, a Cretaceous - aged Ural-Alaskan intrusion in an arc setting. Magma pulses of variable sulfur isotopic compositions were focused into a central chamber where sulfide-bearing magma spread laterally. Trapped silicate liquid was efficiently expelled, leaving sulfide-bearing ultramafic cumulates. A less turbulent environment is indicated for sheet-like intrusions that carry disseminated sulfide mineralization in the Duluth Complex within the MRS. However, the potential ore sequences were built from multiple pulses of magma of distinct S isotope values that had interacted with sulfidic country rocks characterized by different S isotope compositions. Hence, the focusing of magmas from different pathways has been essential for the generation of potential sulfide-rich ore bodies in the Duluth Complex as well.

  17. Determining a pre-mining radiological baseline from historic airborne gamma surveys: a case study.

    PubMed

    Bollhöfer, Andreas; Beraldo, Annamarie; Pfitzner, Kirrilly; Esparon, Andrew; Doering, Che

    2014-01-15

    Knowing the baseline level of radioactivity in areas naturally enriched in radionuclides is important in the uranium mining context to assess radiation doses to humans and the environment both during and after mining. This information is particularly useful in rehabilitation planning and developing closure criteria for uranium mines as only radiation doses additional to the natural background are usually considered 'controllable' for radiation protection purposes. In this case study we have tested whether the method of contemporary groundtruthing of a historic airborne gamma survey could be used to determine the pre-mining radiological conditions at the Ranger mine in northern Australia. The airborne gamma survey was flown in 1976 before mining started and groundtruthed using ground gamma dose rate measurements made between 2007 and 2009 at an undisturbed area naturally enriched in uranium (Anomaly 2) located nearby the Ranger mine. Measurements of (226)Ra soil activity concentration and (222)Rn exhalation flux density at Anomaly 2 were made concurrent with the ground gamma dose rate measurements. Algorithms were developed to upscale the ground gamma data to the same spatial resolution as the historic airborne gamma survey data using a geographic information system, allowing comparison of the datasets. Linear correlation models were developed to estimate the pre-mining gamma dose rates, (226)Ra soil activity concentrations, and (222)Rn exhalation flux densities at selected areas in the greater Ranger region. The modelled levels agreed with measurements made at the Ranger Orebodies 1 and 3 before mining started, and at environmental sites in the region. The conclusion is that our approach can be used to determine baseline radiation levels, and provide a benchmark for rehabilitation of uranium mines or industrial sites where historical airborne gamma survey data are available and an undisturbed radiological analogue exists to groundtruth the data.

  18. Effect of weathering product assemblages on Pb bioaccessibility in mine waste: implications for risk management.

    PubMed

    Palumbo-Roe, Barbara; Wragg, Joanna; Cave, Mark R; Wagner, Doris

    2013-11-01

    General assessments of orebody types and associated mine wastes with regard to their environmental signature and human health hazards are needed to help in managing present and historical mine waste facilities. Bioaccessibility tests and mineralogical analysis were carried out on mine waste from a systematic sampling of mine sites from the Central Wales orefield, UK. The bioaccessible Pb widely ranged from 270 to 20,300 mg/kg (mean 7,250 mg/kg, median 4,890 mg/kg), and the bioaccessible fraction from 4.53 to >100% (mean 33.2%, median 32.2%), with significant (p=0.001) differences among the mine sites. This implies sensitivity of bioaccessibility to site-specific conditions and suggests caution in the use of models to assess human health impacts generalised on the basis of the mineral deposit type. Mineralogical similarities of the oxidation products of primary galena provided a better control over the observed Pb bioaccessibility range. The higher Pb bioaccessibility (%) was related to samples containing cerussite, irrespective of the presence of other Pb minerals in the mineral assemblage; lower Pb bioaccessibility resulted where anglesite was the main Pb mineral phase and cerussite was absent. A solubility diagram for the various Pb minerals in the waste was derived using PHREEQC model, and the experimental Pb concentrations, measured in the simulated gastric solution, were compared with the equilibrium modelling results. For samples containing cerussite, the model well predicted the soluble Pb concentrations measured in the gastric solution, indicative of the carbonate mineral phase control on the Pb in solution for these samples and little kinetic control on the dissolution of cerussite. On the contrary, most mine waste samples containing dominant anglesite and or plumbojarosite (no cerussite) had lower solution Pb values, falling at or below the anglesite and plumbojarosite solubility equilibrium concentrations, implying kinetic or textural factors hindering

  19. Zinc isotopes in sphalerite from base metal deposits in the Red Dog district, northern Alaska

    USGS Publications Warehouse

    Kelley, K.D.; Wilkinson, J.J.; Chapman, J.B.; Crowther, H.L.; Weiss, D.J.

    2009-01-01

    Analyses of sphalerite samples from shale-hosted massive sulfide and stratigraphically underlying vein breccia deposits in the Red Dog district in northern Alaska show a range ??66Zn values from zero to 0.60 per mil. The lowest values are observed in the vein breccia deposits, and the stratigraphically overlying (but structurally displaced) shale-hosted massive sulfide deposits show a systematic trend of increasing ??66Zn values from south to north (Main-Aqqaluk-Paalaaq-Anarraaq). The ??66Zn values are inversely correlated with sphalerite Fe/Mn ratio and also tend to be higher in low Cu sphalerite, consistent with precipitation of lower ??66Zn sphalerite closer to the principal hydrothermal fluid conduits. The most likely control on isotopic variation is Rayleigh fractionation during sulfide precipitation, with lighter zinc isotopes preferentially incorporated in the earliest sphalerite to precipitate from ore fluids at deeper levels (vein breccias) and close to the principal fluid conduits in the orebodies, followed by precipitation of sulfides with higher ??66Zn values in shallower and/or more distal parts of the flow path. There is no systematic variation among the paragenetic stages of sphalerite from a single deposit, suggesting an isotopically homogeneous zinc source and consistent transport-deposition conditions and/or dissolution-reprecipitation of earlier sphalerite without significant fractionation. Decoupled Zn and S isotope compositions are best explained by mixing of separate metal- and sulfur-bearing fluids at the depositional site. The results confirm that Zn isotopes may be a useful tracer for distinguishing between the central and distal parts of large hydrothermal systems as previously suggested and could therefore be of use in exploration. ?? 2009 by Economic Geology.

  20. Ore deposits and epithermal evidences associated with intra-magmatic faults at Aïn El Araâr-Oued Belif ring structure (NW of Tunisia)

    NASA Astrophysics Data System (ADS)

    Aissa, Wiem Ben; Aissa, Lassaâd Ben; Amara, Abdesslem Ben Haj; Tlig, Said; Alouani, Rabah

    2017-03-01

    Hydrothermal ore deposits at Aïn El Araâr-Oued Belif location are classified as epithermal deposits type. The ore bodies are hosted by upper Turonian (8-9 M.y) volcanic rhyodacitic complex. Polymetallic sulfide orebodies are mainly concentrated within intra-magmatic faults. Petrographic, XRD, and TEM-STEM investigations revealed that ore minerals are essentially, arsenopyrite, pyrite, chalcopyrite, pyrrhotite, hematite, goethite and magnetite with Au, Ag and Pt trace metals. Gangue minerals are mainly adularia, quartz, sericite, alunite, tridymite, chlorite, phlogopite and smectite. Epithermal alteration is well zoned with four successive characteristic zones: (1) zone of quartz-adularia-sericite and rare alunite; (2) zone of kaolinite and plagioclase albitization; (3) intermediate zone of illite-sericite; (4) sapropelic alteration type zone of chlorite-smectite and rare illite. This can be interpreted as a telescoping of two different acidity epithermal phases; low sulfidation (adularia-sericite) and high sulfidation (quartz-alunite), separated in time or due to a gradual increase of fluids acidity and oxicity within the same mineralization phase. Brecciated macroscopic facies with fragments hosting quartz-adularia-sericite minerals (low-sulfidation phase) without alunite, support the last hypothesis. Geodynamic context and mineral alteration patterns are closely similar to those of Maria Josefa gold mine at SE of Spain which exhibit a volcanic-hosted epithermal ore deposit in a similar vein system, within rhyolitic ignimbrites, altered to an argillic assemblage (illite-sericite abundant and subordinate kaolinite) that grades outwards into propylitic alteration (Sanger-von Oepen et al. (1990)). Mineralogical and lithologic study undertaken in the volcanic host rock at Aïn El Araâr-Oued Belif reveals a typical epithermal low-sulfidation and high-sulfidation ore deposits with dominance of low-sulfidation. Host rocks in these systems range from silicic to

  1. Results of deep exploratory drilling between long and Newark Valleys, White Pine County, Nevada - implications for oil migration in the nearby Yankee gold mine paleohydrothermal system

    SciTech Connect

    Pinnell, M.L. ); Hulen, J.B. ); Cox, J.W. )

    1993-08-01

    In mid-1992, a consortium headed by Pioneer Oil and Gas (Midvale, Utah) drilled a deep (6700 ft) exploratory well in the southern Ruby Mountains-Buck Mountain are near the Alligator Ridge mining district in White Pine County, Nevada. The test well is located 1.5 mi southwest of USMX, Inc.'s, Yankee gold mine, an open-pit operation centered on a Carlin-type, sediment-hosted gold orebody noteworthy for containing abundant, fracture-controlled live oil. The Pioneer well as dry, but intersected much of the same stratigraphic section hosting gold at Yankee, thereby providing valuable clues to mechanisms of oil migration at this unusual, oil-bearing precious-metal deposit. Most of the gold at Yankee is hosted by the Devonian Pilot Shale, with a basal argillaceous limestone containing the bulk of the deposit's live oil. The equivalent section in the Pioneer wildcat well is a silty calcareous dolomite. Whereas the basal Pilot limestone at Yankee is rich in thick, locally gold- and arsenic-anomalous calcite veins and modules hosting abundant oil-bearing fluid inclusion, the basal Pilot dolomite in the Pioneer well contains only a few thin calcite-pyrite veinlets devoid of fluid inclusions. Moreover, the Yankee calcite veins have the same light-stable-isotope signatures as hydrothermal carbonate veins near or elsewhere in the Alligator Ridge district. These relationships imply that oil at Yankee migrated in the same hydrothermal system responsible for gold mineralization. Such systems elsewhere in the eastern Basin and Range, given favorable source rocks, traps, seals, and migratory pathways, might well have formed not only gold deposits, but also rich, spatially coincident oil reservoirs.

  2. Detailed 40Ar/39Ar dating of geologic events associated with the Mantos Blancos copper deposit, northern Chile

    NASA Astrophysics Data System (ADS)

    Oliveros, Verónica; Féraud, Gilbert; Aguirre, Luis; Ramírez, Luis; Fornari, Michel; Palacios, Carlos; Parada, Miguel

    2008-03-01

    The 40Ar/39Ar geochronological method was applied to date magmatic and hydrothermal alteration events in the Mantos Blancos mining district in the Coastal Cordillera of northern Chile, allowing the distinction of two separate mineralization events. The Late Jurassic Mantos Blancos orebody, hosted in Jurassic volcanic rocks, is a magmatic-hydrothermal breccia-style Cu deposit. Two superimposed mineralization events have been recently proposed. The first event is accompanied by a phyllic hydrothermal alteration affecting a rhyolitic dome. The second mineralization event is related to the intrusion of bimodal stocks and sills inside the deposit. Because of the superposition of several magmatic and hydrothermal events, the obtained 40Ar/39Ar age data are complex; however, with a careful interpretation of the age spectra, it is possible to detect complex histories of successive emplacement, alteration, mineralization, and thermal resetting. The extrusion of Jurassic basic to intermediate volcanic rocks of the La Negra Formation is dated at 156.3 ± 1.4 Ma (2 σ) using plagioclase from an andesitic lava flow. The first mineralization event and associated phyllic alteration affecting the rhyolitic dome occurred around 155-156 Ma. A younger bimodal intrusive event, supposed to be equivalent to the bimodal stock and sill system inside the deposit, is probably responsible for the second mineralization event dated at ca. 142 Ma. Other low-temperature alteration events have been dated on sericitized plagioclase at ca. 145-146, 125, and 101 Ma. This is the first time that two distinct mineralization events have been documented from radiometric data for a copper deposit in the metallogenic belt of the Coastal Cordillera of northern Chile.

  3. Geological and petrological aspects of Ni-Cu-PGE mineralization in the early Paleoproterozoic Monchegorsk layered mafic-ultramafic complex, Kola Peninsula

    NASA Astrophysics Data System (ADS)

    Sharkov, E. V.; Chistyakov, A. V.

    2014-05-01

    The Early Paleoproterozoic Monchegorsk Complex comprises two independent large layered mafic-ultramafic intrusions: the Monchegorsk pluton and the Main Range massif formed about 2.50 and 2.46 Ga ago, respectively. They are composed of similar cumulates, though they differ somewhat in the isotopic parameters of rocks, cumulate stratigraphy and derived from siliceous high-Mg series melts that arose in the same large long-living volcanic center. The economic syngenetic Ni-Cu-PGE sulfide mineralization related to the earlier Monchegorsk pluton is represented by two types of ores. The first type, pertaining to fractionation of the primary melt, is opposite to the reef formed due to injection of a special ore-bearing melt into the solidifying intrusive chamber. The primary magmatic mineralization is largely composed of Ni-Fe-Cu sulfides and Pd-Pt sulfides, bismuthides, and tellurides. Only small PGE and probably chromite occurrences are related to the Main Range massif. In the Mid-Paleoproterozoic (2.0-1.9 Ga), the complex was transformed into a collage of tectonic blocks confined to the regional fault zone. The Monchegorsk pluton was retained better, and only rocks of its southern framework were involved into tectonic and metamorphic reworking with the formation of economic metamorphic low-sulfide PGE mineralization with widespread Pd and Pt telluro-bismuthides, arsenides, stannides, antimonides, and selenides. The ore formation was accompanied by PGE redistribution and segregation of lenticular orebodies with diffuse contours. Thus, the Monchegorsk ore cluster is characterized by juxtaposition of unaltered primary magmatic deposits and those formed as a result of their metamorphism and distinguished from the former by structure and composition. The comparative study of these deposits opens up new possibilities for comprehending ore-forming processes in the same situations.

  4. Remote sensing applied to the exploration for uranium-mineralized breccia pipes in northwestern Arizona

    SciTech Connect

    Kwarteng, A.M.Y.

    1988-01-01

    Exploration for uranium-mineralized breccia pipes in northwestern Arizona has been active because of the high-grade ore they contain, which may also include such by-products as Ag, Au, Cu, Pb, Zn, and V. These breccia pipes were formed from the collapse of the overlying sedimentary strata into karst caverns developed in the Mississippian Redwall Limestone; mineralization occurred between 200 and 220 m.y. ago as determined previously by U-Pb isotopic analyses. Spectroscopic and statistical analyses of field, laboratory, and digital Landsat Thermatic Mapper (TM) data were carried out to determine the fundamental spectral and mineralogical differences between samples on the surface of breccia pipes and their background areas. Spectroscopic and XRD mineralogical studies clearly demonstrate that hydrothermally altered rocks associated with mineralized breccia pipes are distinguished from the surrounding rocks by the Fe{sup 3+}, hydroxyl, and carbonate minerals content. Discriminant analyses of field, laboratory, and TM data indicates that 64-80% of the samples collected on the surfaces of breccia pipes and their immediately surrounding areas were correctly classified. Digitally enhanced TM images printed at the scale of 1:100,000 resulted in the recognition of more than 80% of previously known orebodies as well as additional anomalies identified in the study areas. Digital image processing techniques were applied to airborne geophysical data consisting of apparent resistivity, total-field magnetics, derived overburden thickness, and very low-frequency electromagnetics (VLF-EM) to evaluate the utility of the data sets for breccia pipe exploration. The processing and critical analysis of the geophysical data is apparently the most promising approach to breccia pipe exploration in this study.

  5. Geoelectromagnetic Exploration For Natural Resources: Models, Case Studies And Challenges

    NASA Astrophysics Data System (ADS)

    Meju, Maxwell A.

    This paper presents a tutorial review of electrical and electromagnetic(herein collectively called geoelectromagnetic) methods as applied in the search for natural resources. First, the paper discusses the technical problems and advances in geoelectromagnetic methods in the last decade. A scheme for integrating electrical and electromagnetic depth sounding data is suggested.Then, for natural resources exploration, it focuses on three themes: (1) understandinggeological models of resource targets, their physical properties, and the development of conceptual geoelectromagnetic exploration models, (2) overview of geoelectromagnetic case studies in resourceexploration, and (3) outstanding challenges in exploration. For brevity, model development is restricted to groundwater, geothermal and hydrocarbon resources, metallic ore-bodies (exemplified byvolcanogenic massive sulphides, porphyry coppers, and epithermal and Archaean greenstone belt gold deposits) and diamonds. In the treatment of resource exploration in this paper, the unifying themeis that geochemical processes of weathering and hydrothermal alteration form clayey products that may render natural resource targets directly or indirectly detectable by their resistivity characteristics.Since hydrated clays are an important feature of most resource types and are major causes of low resistivity anomalies in geoelectromagnetic exploration, they may be taken as providing detectable marker horizons or pathfinders and a basis for developing a consistent investigative approachfor natural resources. However, it is recognised that no single resource model or standard approach may be universally applicable. Natural resource systems are inherently 3D and require large numbers of depth soundings at high station densities to image adequately. Thus, developing methodsof increasing the productivity of data acquisition, the development of better 3D software tools and lowering costs are seen as the major challenges facing the use

  6. Calculation and inversion of two-dimensional gravity in the vicinity of Lake Tuz, Turkey

    NASA Astrophysics Data System (ADS)

    Seren, A.; Cavsak, H.; Jacoby, W.

    2000-01-01

    An example of gravity inversion and interpretation is presented which demonstrates how a priori information can be used to derive reliable, though complex models. In this case, the geometry of the studied model profile has been constructed on the basis of seismic and geological data. The densities used in the forward calculations were obtained from laboratory measurements of drill cores, from density-velocity relationships, and from Nettleton's method of fitting gravity and topography. In the seismic section 21 'formations' are distinguished leading to a very complex gravity model. What is called 'formations' here, are two-dimensional bodies which are distinguished from each other seismically and perhaps partly by a priori knowledge. Some of the formations have approximately the same densities and could thus be treated as single masses. On the other hand, the same formation may have a complex form and may consist of separate bodies, e.g. as a consequence of faulting; they are still treated as single bodies. Accordingly, the number of bodies of constant density could be reduced to eight. The gravity effect calculated for the model with the initial density assumptions regionally clearly deviated from the observed anomaly. More probable densities were then determined for the formations with inversion calculations in an attempt to optimally fit the calculations to the observations. Always, a better fit could be obtained. In one case about 5 g/cm 3 density was calculated for a single small formation. The proposal is to either investigate whether or not there may exist an ore-body worthwhile for further exploration or to change the seismic section on a limited scale. If the high density is not accepted, compatibility between observed and calculated gravity and plausible densities can be achieved by changing the formation volume (thickness). Other formational densities down to the depth of 32 km have been found to be between 2 and 2.7 g/cm 3.

  7. Post-remediation biomonitoring of pesticides and other contaminants in marine waters and sediment near the United Heckathorn Superfund Site, Richmond, California

    SciTech Connect

    LD Antrim; NP Kohn

    2000-05-26

    dieldrin concentrations in mussel tissues were dramatically lower than measured levels from preremediation surveys and also lower than Year 1 levels from post-remediation biomonitoring. The lowest levels were found at the Richmond Inner Harbor Channel station (4.1 {micro}g/kg total DDT and 0.59 {micro}g/kg dieldrin, wet weight; mean of resident and transplant mussels). Mean chlorinated pesticide concentrations were highest at Lauritzen Canal/End (82 {micro}g/kg total DDT and 7.1 {micro}g/kg dieldrin, wet weight), followed by Lauritzen Canal/Mouth (22 {micro}/kg total DDT and 1.7 {micro}g/kg dieldrin, wet weight) and Santa Fe Channel/End (7.5 {micro}g/kg total DOT and 0.61 {micro}g/kg dieldrin, wet weight). These levels are 95% to 99% lower than those recorded by the California State Mussel Watch program prior to EPA's response actions. The levels of PCBs in mussel tissue were also reduced by 93% to 97% from preremediation levels. Surface sediment concentrations of dieldrin and DDT in November 1998 were highest in samples from the head or north end of Lauritzen Canal and progressively lower toward the mouth, or south end. Total DDT ranged from 130 ppm (dry weight) at the north end to 3 ppm at the south end. Dieldrin concentrations decreased from 3,270 ppb (dry weight) at the north end to 52 ppb at the south end. These results confirmed elevated pesticide concentrations in sediments collected from Lauritzen Channel by Anderson et al. (1999). The pesticide concentrations were lower than maximum concentrations found in the 1993 Remedial Investigation but comparable to the median levels measured before remediation was completed. Sediment analyses also showed the presence of elevated PCB aroclor 1254, and very high levels of polynuclear aromatic hydrocarbons (PAH) in Lauritzen Channel.

  8. Simulation of saltwater movement in the Floridan aquifer system, Hilton Head Island, South Carolina

    USGS Publications Warehouse

    Bush, Peter W.

    1988-01-01

    Freshwater to supply Hilton Head Island, S.C., is obtained from the upper permeable zone of the Upper Floridan aquifer. Long-term pumping at Savannah, Ga., and the steadily increasing pumping on Hilton Head Island, have lowered Upper Floridan heads near the center of the island from about 10 feet above sea level to about 6 to 7 feet below sea level. The seaward hydraulic gradient that existed before pumping began has been reversed, thus increasing the potential for saltwater intrusion. Simulations of predevelopment, recent, and future ground-water flow in the Floridan aquifer system beneath the north end of Hilton Head Island and Port Royal Sound are presented. A finite-element model for fluid-density-dependent ground-water flow and solute transport was used in cross section. The general configuration of the simulated predevelopment flowfield is typical of a coastal aquifer having a seaward gradient in the freshwater. The freshwater flows toward Port Royal Sound over an intruding wedge of saltwater. The simulated flowfield at the end of 1983 shows that ground water in the Floridan aquifer system beneath most of Hilton Head Island has reversed its predevelopment direction and is moving toward Savannah. The distribution of chloride concentrations, based on simulation at the end of 1983, is about the same as the predevelopment distribution of chloride concentrations obtained from simulation. Results of two 50-year simulations from 1983 to 2034 suggest that there will be no significant threat of saltwater intrusion into the upper permeable zone of the Upper Floridan aquifer if heads on Hilton Head Island remain at current levels for the next 45 to 50 years. However, if head decline continues at the historical rate, any flow that presently occurs from the north end of the island toward Port Royal Sound will cease, allowing lateral intrusion of saltwater to proceed. Even under these conditions, chloride concentrations in the upper permeable zone of the Upper Floridan

  9. Record of Technical Change 2 for Closure Report for Corrective Action Unit 204: Storage Bunkers, Nevada Test Site, Nevada, Revision 0

    SciTech Connect

    Krauss, Mark J.; Birney, Cathleen

    2006-04-01

    CAS 05-33-01, Kay Blockhouse, consists of an area of approximately 11 acres and includes the Kay Blockhouse, two bum pits with steel frames, one bum pit with a soil berm, two open pits, two steel-lined subsurface pits, one berm with embedded piping, one berm with piping debris, a burn area with a large concrete block with an embedded steel prong, and one open pit with a concrete foundation at the north end. The Kay Blockhouse was constructed in 1951 and was used as an instrumentation bunker for Operation Ranger, a series of five atmospheric nuclear tests. The burn pits and other surface features within the CAS boundary were not part of the nuclear testing. The Kay Blockhouse is constructed of concrete with a wooden entryway door. The details of the construction of the floor are unknown (NNSA/NSO, 2004b). During closure activities, lead- and radiologically impacted soil was removed, and verification samples were collected. Friable asbestos material was removed from the burn pits; the asbestos and steel frames from the bum pits were disposed of at the Area 23 Sanitary Landfill. In addition, the two steel-lined pits were filled with native soil and capped with 1.5 ft of concrete. The bunker was secured by installing security fencing and a gate around the entrance to the bunker. The RMA was reestablished and fenced with T-post and wire-rope fencing (NNSA/NSO, 2006a).

  10. Neutron Radiographic Inspection of Industrial Components using Kamini Neutron Source Facility

    NASA Astrophysics Data System (ADS)

    Raghu, N.; Anandaraj, V.; Kasiviswanathan, K. V.; Kalyanasundaram, P.

    2008-03-01

    Kamini (Kalpakkam Mini) reactor is a U233 fuelled, demineralised light water moderated and cooled, beryllium oxide reflected, low power (30 kW) nuclear research reactor. This reactor functions as a neutron source with a flux of 1012 n/cm2 s-1 at core centre with facilitates for carrying out neutron radiography, neutron activation analysis and neutron shielding experiments. There are two beam tubes for neutron radiography. The length/diameter ratio of the collimators is about 160 and the aperture size is 220 mm×70 mm. Flux at the outer end of the beam tube is ˜106-107 n/cm2 s. The north end beam tube is for radiography of inactive object while the south side beam tube is for radiography of radioactive objects. The availability of high neutron flux coupled with good collimated beam provides high quality radiographs with short exposure time. The reactor being a unique national facility for neutron radiography has been utilized in the examination of irradiated components, aero engine turbine blades, riveted plates, automobile chain links and for various types of pyro devices used in the space programme. In this paper, an overview of the salient features of this reactor facility for neutron radiography and our experience in the inspection of a variety of industrial components will be given.

  11. Sources of water and nitrogen to the Widefield Aquifer, southwestern El Paso County, Colorado

    USGS Publications Warehouse

    Edelmann, Patrick; Cain, Doug

    1985-01-01

    The Widefield aquifer near Colorado Springs, Colorado, is recharged primarily by Fountain Creek and, to a lesser extent, by infiltration and percolation of water from the land surface and from groundwater inflow. During the past 20 to 30 years, concentrations of nitrate (as nitrogen) in the Widefield aquifer have increased from 0.5 to 3.0 milligrams/L to nearly 10 milligrams/L, and occasionally exceed the drinking-water standard of 10 milligrams/L as nitrogen. During the summer of 1982, the concentrations of nitrite plus nitrate as nitrogen in water in the aquifer ranged from 3.2 to 15 milligrams/L with a mean concentration of 6.9 milligrams/L. In general, the nitrite-plus-nitrate concentrations are greatest near the north end of the aquifer, probably resulting from effluent from Colorado Springs Sewage Treatment Plant being discharged to Fountain Creek. During 1982, 93% of the total estimated 160 tons of nitrogen available to enter the Widefield aquifer was from the Colorado Springs Sewage Treatment Plant. However, a significant proportion of this nitrogen may have been lost through denitrification. (USGS)

  12. Data Report Documenting the Rattachment of the CC Cryostat Heads

    SciTech Connect

    Luther, R.; /Fermilab

    1990-11-06

    Reassembly of the inner pressure vessel of a seventeen foot diameter by ten foot long double wall toroidal shaped vessel in which each vessel consists of two concentric cylinders which are capped at each end by an annular dished head. Attached drawing 1, 2, 3, and 4 (all Revision 1) show the repair work items. The work covered by this data report applies only to the inner pressure vessel (See Item 8 remarks) . These work items are: (1) Two circumferential weld seams ( Seams A and G on attached drawing 2) of the north end annular dished head. (2) Two circumferential weld seams (Seam C and F on attached drawing 2) of the south end annular dished head. (3) Rerolling and rewelding of the vertical seam of the 64 3/8 inch nominal inside diameter tube (seam L on attached drawing 2) (4) Welding of the two dust catchers inside the inner pressure vessel (Seams Nand 0 on attached drawing 2). The dust catchers are attachments to pressure parts and were supplied by Fermi National Accelerator Laboratory. (5) Welding of the outer tube of the beam bypass tube (Seams I and K on attached drawing 3).

  13. Geophysical evidence for the intersection of the St Paul, Cape Palmas and Grand Cess fracture zones with the continental margin of Liberia, West Africa

    USGS Publications Warehouse

    Behrendt, John C.; Schlee, J.; Robb, James M.

    1974-01-01

    PUBLISHED reconstructions of Gondwana continent1 (Fig. la) show a gap in fit near the junction of the Americas and Africa. To study this critical area, the Unitedgeo I made geophysical measurements and collected rock samples across the continental margin of Liberia (USGS-IDOE cruise leg 5) in November 1971. Figure Ib indicates the location of the 5,400 km of ship track on a generalised bathymetric map2. We shall discuss the data in detail elsewhere. Here we present the evidence for the existence of three fracture zones, two of which have not been reported previously, intersecting the continental margin at the north end of the South Atlantic, which remained closed probably until Cretaceous time. We suggest that Precambrian structures on the African continent controlled the location of these fracture zones. Figure Ic compares gravity and magnetic profiles and interpretations of the seismic profiles for three selected lines (27, 30 and 34) crossing the Grand Cess, Cape Palmas and St Paul fracture zones, respectively. ?? 1974 Nature Publishing Group.

  14. STS-112/Atlantis/ISS 9A Pre-Launch - Launch On-Orbit - Landing - Crew Egress

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The video starts with an introduction of the crew of Space Shuttle Atlantis on STS-112 at their customary pre-flight meal. The crew consists of Commander Jeffrey Ashby, Pilot Pam Melroy, and Mission Specialists David Wolf, Sandra Magnus, Piers Sellers, and Fyodor Yurchikhin. The crew is then shown during suit-up, while exiting the Operations and Checkout Building to board the Astrovan, and during ingress and seating. Launch views include: Beach Tracker, VAB, PAD-B, Tower-1, DLTR-3, Grandstand, Cocoa Beach DOAMS, Playalinda DOAMS, UCS-23, OTV-170, OTV-171, and External Tank Camera. On-orbit footage includes the Atlantis orbiter docking with the ISS (International Space Station). The video shows clips of extravehicluar activities (EVAs), and some of the tasks performed during the mission. Footage included shows the installation of the S1 Truss onto the ISS with the Space Station Remote Manipulator System (Canadarm 2), Canadarm 2 carrying the Ammonia Tank Assembly prior to connection, the checkout of the Thermal Radiator Rotary Joint, the soft docking of an S-Band antenna, and the deployment of the S1 Radiator. An onboard repair of the ISS humidity separator is also shown. Landing views include: VAB, Tower 1, Mid-Field, Runway South End, Runway North End, Tower-2, Cocoa Beach DOAMS, and PPOV. Kennedy Space Center managers greet the crew upon arrival, and Commander Ashby gives a brief speech while standing with his crew members.

  15. Neutron Radiographic Inspection of Industrial Components using Kamini Neutron Source Facility

    SciTech Connect

    Raghu, N.; Anandaraj, V.; Kasiviswanathan, K. V.; Kalyanasundaram, P.

    2008-03-17

    Kamini (Kalpakkam Mini) reactor is a U{sup 233} fuelled, demineralised light water moderated and cooled, beryllium oxide reflected, low power (30 kW) nuclear research reactor. This reactor functions as a neutron source with a flux of 10{sup 12} n/cm{sup 2} s{sup -1} at core centre with facilitates for carrying out neutron radiography, neutron activation analysis and neutron shielding experiments. There are two beam tubes for neutron radiography. The length/diameter ratio of the collimators is about 160 and the aperture size is 220 mmx70 mm. Flux at the outer end of the beam tube is {approx}10{sup 6}-10{sup 7} n/cm{sup 2} s. The north end beam tube is for radiography of inactive object while the south side beam tube is for radiography of radioactive objects. The availability of high neutron flux coupled with good collimated beam provides high quality radiographs with short exposure time. The reactor being a unique national facility for neutron radiography has been utilized in the examination of irradiated components, aero engine turbine blades, riveted plates, automobile chain links and for various types of pyro devices used in the space programme. In this paper, an overview of the salient features of this reactor facility for neutron radiography and our experience in the inspection of a variety of industrial components will be given.

  16. Latitudinal-Related Variation in Wintering Population Trends of Greylag Geese (Anser Anser) along the Atlantic Flyway: A Response to Climate Change?

    PubMed Central

    Ramo, Cristina; Amat, Juan A.; Nilsson, Leif; Schricke, Vincent; Rodríguez-Alonso, Mariano; Gómez-Crespo, Enrique; Jubete, Fernando; Navedo, Juan G.; Masero, José A.; Palacios, Jesús; Boos, Mathieu; Green, Andy J.

    2015-01-01

    The unusually high quality of census data for large waterbirds in Europe facilitates the study of how population change varies across a broad geographical range and relates to global change. The wintering population of the greylag goose Anser anser in the Atlantic flyway spanning between Sweden and Spain has increased from 120 000 to 610 000 individuals over the past three decades, and expanded its wintering range northwards. Although population sizes recorded in January have increased in all seven countries in the wintering range, we found a pronounced northwards latitudinal effect in which the rate of increase is higher at greater latitudes, causing a constant shift in the centre of gravity for the spatial distribution of wintering geese. Local winter temperatures have a strong influence on goose numbers but in a manner that is also dependent on latitude, with the partial effect of temperature (while controlling for the increasing population trend between years) being negative at the south end and positive at the north end of the flyway. Contrary to assumptions in the literature, the expansion of crops exploited by greylag geese has made little contribution to the increases in population size. Only in one case (expansion of winter cereals in Denmark) did we find evidence of an effect of changing land use. The expanding and shifting greylag population is likely to have increasing impacts on habitats in northern Europe during the course of this century. PMID:26465601

  17. EXTREME CONDITIONS IN A CLOSE ANALOG TO THE YOUNG SOLAR SYSTEM: HERSCHEL OBSERVATIONS OF ε ERIDANI

    SciTech Connect

    Greaves, J. S.; Sibthorpe, B.; Holland, W. S.; Acke, B.; Vandenbussche, B.; Blommaert, J. A. D. L.; Pantin, E. E.; Dominik, C.; Barlow, M. J.; Bendo, G. J.; Dent, W. R. F.; Di Francesco, J.; Fridlund, M.; Gear, W. K.; Harvey, P. M.; Hogerheijde, M. R.; Ivison, R. J.; and others

    2014-08-10

    Far-infrared Herschel images of the ε Eridani system, seen at a fifth of the Sun's present age, resolve two belts of debris emission. Fits to the 160 μm PACS image yield radial spans for these belts of 12-16 and 54-68 AU. The south end of the outer belt is ≈10% brighter than the north end in the PACS+SPIRE images at 160, 250, and 350 μm, indicating a pericenter glow attributable to a planet ''c''. From this asymmetry and an upper bound on the offset of the belt center, this second planet should be mildly eccentric (e{sub c} ≈ 0.03-0.3). Compared to the asteroid and Kuiper Belts of the young Sun, the ε Eri belts are intermediate in brightness and more similar to each other, with up to 20 km sized collisional fragments in the inner belt totaling ≈5% of an Earth mass. This reservoir may feed the hot dust close to the star and could send many impactors through the Habitable Zone, especially if it is being perturbed by the suspected planet ε Eri b, at semi-major axis ≈3 AU.

  18. Level of Lake Lahontan during deposition of the Trego Hot Springs tephra about 23,400 years ago

    NASA Astrophysics Data System (ADS)

    Davis, Jonathan O.

    1983-05-01

    The Trego Hot Springs tephra bed is a silicic tephra about 23,400 yr old, found at several localities in pluvial lake sediments in northern Nevada, southern Oregon, and northeastern California. It has been characterized petrographically, by the major and minor element chemistry of its glass, and by its stratigraphic position with respect to other tephra layers. At a newly described locality on Squaw Creek, northwest of Gerlach, Nevada, at the north end of the Smoke Creek Desert, Trego Hot Springs tephra has been found in sediments of the Sehoo and Indian Lakes formations. The depositional environments of these sediments show that when the tephra fell, pluvial Lake Lahontan stood between 1256 and 1260 m, and that immediately thereafter the lake rose to at least 1275 m. These data corroborate earlier findings by Benson ( Quaternary Research9, 300-318) from radiometric dating of calcareous tufa. However, the Lake Lahontan area has been affected by isostatic subsidence and rebound in response to changing water loads, so that caution is required in the use of lakeshore elevations in correlation.

  19. Geophysical Exploration of the Red Rocks Canyon Landfill in Colorado Springs, Colorado

    NASA Astrophysics Data System (ADS)

    Calhoun, N.; Morin, C.; Gy250, S.; Bank, C.

    2005-05-01

    Our introductory geophysics class conducted a survey of the Red Rocks Canyon landfill to determine its boundaries, depth, type of fill, and groundwater runoff patterns. In the 1970s and 1980s the canyon was filled with domestic waste, and has recently been acquired by the city to extend an existing park. Our results in general portray a heterogenous subsurface and reveal that the landfill likely contains many metallic objects. More specifically we found the following: A negative Bouguer anomaly across the landfill matches a model for a ~25 m thick fill. Resistivity is much lower on the landfill than off, but we could not confirm our hypothesis that the landfill drains water through the north end of the canyon. Our seismic data are inconclusive, we think that our assumption of a planar bottom and seismically homogenous fill is violated. The magnetic data show on average higher total values, large (>1,000 nT) variations and high magnetic gradients on the landfill; because this method is fast and very clearly maps the landfill boundaries we propose a magnetic survey to detect possible unregistered dumps outside the mapped boundaries of the landfill. Measuring ground conductivity utilizing an electromagnetic survey produces significantly higher values on the landfill than off. Additionally, directional anisotropies match the direction of the strike of the geological formations adjacent to the landfill and are more randomly oriented on the landfill.

  20. Ups and downs on spreading flanks of ocean-island volcanoes: evidence from Mauna Loa and Kīlauea

    USGS Publications Warehouse

    Lipman, Peter W.; Eakins, Barry W.; Yokose, Hisayoshi

    2003-01-01

    Submarine-flank deposits of Hawaiian volcanoes are widely recognized to have formed largely by gravitationally driven volcano spreading and associated landsliding. Observations from submersibles show that prominent benches at middepths on flanks of Mauna Loa and Kilauea consist of volcaniclastic debris derived by landsliding from nearby shallow submarine and subaerial flanks of the same edifice. Massive slide breccias from the mature subaerial tholeiitic shield of Mauna Loa underlie the frontal scarp of its South Kona bench. In contrast, coarse volcaniclastic sediments derived largely from submarine-erupted preshield alkalic and transitional basalts of ancestral Kilauea underlie its Hilina bench. Both midslope benches record the same general processes of slope failure, followed by modest compression during continued volcano spreading, even though they record development during different stages of edifice growth. The dive results suggest that volcaniclastic rocks at the north end of the Kona bench, interpreted by others as distal sediments from older volcanoes that were offscraped, uplifted, and accreted to the island by far-traveled thrusts, alternatively are a largely coherent stratigraphic assemblage deposited in a basin behind the South Kona bench.