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At least 235 records · Page 13Linked to original sources
USGS1975

Stratigraphy of Atlantic coastal margin of United States north of Cape Hatteras: Brief survey

A synthesis of studies of sea-floor outcrops of the sedimentary wedge beneath the northeastern United States continental shelf and slope and a reassessment of coastal plain Mesozoic stratigraphy, particularly of the coastal margin, provide insight for estimating the oil and gas potential and provide geologic control for marine seismic investigations of the Atlantic continental margin. The oldest strata known to crop out on the continental slope are late Campanian in age. The Cretaceous-Tertiary contact along the slope ranges from a water depth of 0.6 to 1.5 km south of Georges Bank to 1.8 km in Hudson Canyon. Few samples are available from Tertiary and Late Cretaceous outcrops along the slope. Sediments of the Potomac Group, chiefly of Early Cretaceous age, constitute a major deltaic sequence in the emerged coastal plain. This thick sequence lies under coastal Virginia, Maryland, Delaware, southeastern New Jersey, and the adjacent continental shelf. Marine sands associated with this deltaic sequence may be present seaward under the outer continental shelf. South of the Norfolk arch, under coastal North Carolina, carbonate rocks interfinger with Lower Cretaceous clastic strata. From all available data, Mesozoic correlations in coastal wells between coastal Virginia and Long Island have been revised. The Upper-Lower Cretaceous boundary is placed at the transition between Albian and Cenomanian floras. Potential hydrocarbon source beds are present along the coast in the subsurface sediments of Cretaceous age. Potential reservoir sandstones are abundant in this sequence.

Atlantic coastal plain↗
USGS2004

Toward a comprehensive information system to assist invasive species management in Hawaii and Pacific Islands

The need for coordinated regional and global electronic databases to assist prevention, early detection, rapid response, and control of biological invasions is well accepted. The Pacific Basin Information Node (PBIN), a node of the National Biological Information Infrastructure, has been increasingly engaged in the invasive species enterprise since its establishment in 2001. Since this time, PBIN has sought to support frontline efforts at combating invasions, through working with stakeholders in conservation, agriculture, forestry, health, and commerce to support joint information needs. Although initial emphasis has been on Hawaii, cooperative work with other Pacific islands and countries of the Pacific Rim is already underway and planned.

Weed Science↗
USGS1963

Endothal derivatives as aquatic herbicides in fishery habitats

The disodium salt of 3,6-endoxohexahydrophthalic acid (disodium endothal) and the derivative identified by the manufacturer as the di- N,N ′-dimethylococoamine salt of endothal (coded as TD-47) were particularly effective upon submersed species of aquatic vegetation as contact herbicides. Disodium endothal at concentrations of 0.5 to 10.0 ppmw was effective in controlling approximately 50 per cent of the 19 species of plants involved in 270 tests. TD-47 at concentrations of 0.02 to 10.0 ppmw trolled 77 per cent of the 11 plant species in 94 tests. Algae ( Chara, Cladophora, Pithophora , and Spirogyra ) were more effectively controlled by TD-47 than by disodium endothal. Although TD-47 was at least 10 times more herbicidal than disodium endothal, it was about 100 times more toxic to fish. Disodium endothal was more than 50 per cent effective on submersed aquatic plants at rates in excess of 2.5 ppmw with a wide margin of safety in fish (4- to 10-fold). Disodium endothal had a median tolerance limit ranging from 95 to 150 ppmw in the aggregate of nine fish species tested extensively. Median tolerance limits for TD-47 ranged from about 0.06 to 0.3 ppmw for five species of fish. TD-47 applied at a concentration lethal to fish (0.3 to 1.0 ppmw) was effective as a dual management tool in controlling vegetation and achieving partial or complete renovation of stunted fish populations. Young, growing vegetation was most susceptible to control, and best results were achieved at water temperatures exceeding 60 F. Higher rates were required to kill plants as they matured and stands became dense. Endothal liquid formulations were superior to granules in controlling algal mats, floating and emergent plants. Granules were more effective on submersed rooted plants. TD-47 residues were of short duration. The rate of disappearance depended on time and concentration. Detectable residues disappeared within 8 days following application of 0.3 ppmw and within 2 weeks for 0.6 ppmw. However, 1.0 to 3.0 ppmw took up to 25 days to disappear. Some residues were found in fish-food organisms from treated enclosures 3 weeks after application. Fish flesh showed no absorption of endothal-armeens at sublethal concentrations. Intraperitoneal injection of endothal into fish produced a disturbance of the osmoregulation. The physiological effect of endothal was measured by chemical analysis of blood serum.

Weeds↗
USGS1964

Dichlobenil as a herbicide in fish habitats

Application of 20 to 40 lb/A dichlobenil made prior to emergence accomplished various degrees of control of pondweeds ( Potamogeton diversifolius , P. foliosus , P. pectinatus , P. pusillus ) and a slender naiad ( Najas flexilis ). Coontail ( Ceratophyllum demersum ) was affected only by the higher dosage. Limited control and growth inhibition was achieved on several forms of algae in early spring applications. However, applications made to rooted submersed aquatic plants and filamentous algae ( Cladophora , Pithophora and Chara ) at postemergence stage of development had little herbicidal effect. Dichlobenil was not acutely toxic to fish at herbicidal concentrations. The range of median tolerance limits was 10 to 20 ppmw for pumpkinseed ( Lepomis gibbosus ), bluegill ( L. macrochirus ), redear sunfish ( L. microlophus ), and largemouth bass ( Micropterus salmoides ).

Missouri↗
USGS1965

Diuron, fenuron, monuron, neburon, and TCA mixtures as aquatic herbicides in fish habitats

The substituted urea herbicides were rated according to their effectiveness as aquatic herbicides in this order: diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], monuron [3-(p-chlorophenyl)-1,1-dimethylurea], neburon [1-butyl-3-(3,4-dichlorophenyl)-1-methlyurea] and TCA(trichloroacetic acid) mixtures with them. They showed greatest potential in controlling certain aquatic plants in pre-emergence and early postemergence applications. However, relatively high concentrations were required to control filamentous algae ( Cladophora , Pithophora and Spirogyra ) , chara ( Chara ) , coontail ( Ceratophyllum ) , naiad ( Najas ) , and pondweeds ( Potamogeton ) for periods of time exceeding three months and up to three years. Granular formulations achieved better distribution of herbicides for control of rooted aquatic plants along the margins of lakes and ponds. Wettable powder and liquid emulsifiable concentrates were superior to granular formulations for the control of algae and emergent or floating aquatic plants. Monuron and fenuron were less toxic to fish than were diuron and neburon. The TCA mixtures were somewhat more toxic than the simple ureas. Some species of fish were more sensitive than others and fingerlings more sensitive than adults of the same species. Fish-food organisms were reduced appreciably in plastic enclosures at herbicidal concentrations.

Weeds↗
USGS1965

Control of alligatorweed in South Carolina with granular silvex

Silvex, [2-(2,4,5-trichlorophenoxy)propionic acid], impregnated (20% ae) on clay granules, applied at a rate as low as 20 lb/A ae gave excellent control of well-rooted alligatorweed [ Alternanthera philoxeroides (Mart.) Grieb] growing in less than 18 inches of water. The 2-ethylhexyl ester of silvex was more effective than the potassium salt. Silvex was not effective on floating-mat alligatorweed or in water over 18 inches deep.

South Carolina↗
USGS1893

The Glaciation of the Yellowstone Valley North of the Park

The local glaciers of Quaternary times, of which evidences abound throughout the highest portions of the Rocky mountain cordillera, attained an unusually extensive development in that broad elevated region known as the Yellowstone Park. It was indeed the center of a considerable ice sheet whose glaciers spread out and down the valleys leading from this mountain region in all directions. In the northern part of the park two streams of ice found an outlet for their united flow northward down the valley of the Yellowstone, and they have left impressive memorials of the power and size of this stream that at once attract the attention of the observant traveler on the way to the famous geyser basins of the park. The number and size of the erratic bowlders scattered so abundantly over the valley floor and perched high up on the mountain slopes, can not fail to impress the beholder, while the second canyon of the Yellowstone, known as Yankee Jim canyon, through which the river has cut its way to the broad mountain encircled lower valley, is a grand and perfect piece of ice sculpture that affords striking proof of the power and magnitude of the glacier which once filled the valley. While studying and mapping the geology of a portion of the country north of the Yellowstone Park, under the direction of Mr. Arnold Hague, and for the United States Geological Survey, I found a long desired opportunity to study the glaciation of this interesting region.

Bulletin↗
USGS1896

Yellowstone National Park folio, Wyoming

The area covered by the maps of the Yellowstone National Park folio is represented upon four atlas sheets, known as the Gallatin, Canyon, Lake, and Shoshone sheets, and is embraced between the parallels of 44° and 45° north latitude and the meridians of 110° and 111°. It is situated in the northwest corner of the State of Wyoming, and includes 3,412 square miles.

Wyoming↗