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Page 3338, results 83426 - 83450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Development of a long-term ecological monitoring program in Denali National Park and Preserve, Alaska (USA)
Karen L. Oakley, Edward M. Debevec, Eric A. Rexstad
1999, Conference Paper, Proceedings: North American science symposium: Toward a unified framework for inventorying and monitoring forest ecosystem resources
A Long-term Ecological Monitoring (LTEM) program began at Denali National Park and Preserve, Alaska (USA) in 1992, as a prototype for subarctic parks. The early history of the Denali LTEM program provides insight into the challenges that can arise during monitoring program development. The Denali program has thus far taken...
Modern accumulation rates and a sediment budget for the Eel shelf: a flood-dominated depositional environment
Christopher K. Sommerfield, Charles A. Nittrouer
1999, Marine Geology (154) 227-241
The northern California continental margin is periodically impacted by geologically significant storms, which have a marked influence on terrigenous sediment supply, flood deposition, and long-term accumulation of fine-grained sediment on the Eel shelf. Accumulation of Eel River muds on the adjacent shelf was investigated using 210Pb and 137Cs geochronologies, in...
Chapter 7: Studies of short-lived radionuclides in Santorini volcanics
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 118-128
Disequilibria between the short-lived radioactive nuclides 226Ra, 230Th and 238U in young volcanic rocks can be used both for dating the time of crystallisation of a rock, and as isotopic tracers of the sources of magmas and the chemical evolution of volcanic systems. The principles of these methods have been reviewed extensively elsewhere...
Chapter 8: The evolution of Santorini
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 129-133
There now follows a synthesis of the main results of this study. We interpret the observations in terms of the interplay between magmatic, tectonic and volcanic processes and place these processes within a global context. Santorini has displayed a wide variety of igneous and volcanic phenomena over a period of...
Chapter 4: Compositional zoning and petrology of the Thera pyroclastics
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 58-78
Compositional zoning is a common feature of pyroclastic deposits erupted from calderas worldwide (Smith 1979; Hildreth 1981; Bacon & Druitt 1988; De Silva 1991; Feeley & Davidson 1994). Compositionally zoned tuffs provide a geologically instantaneous snapshot of the vertical stratigraphy and density stratification in the chamber immediately before eruption. Magma...
Chapter 2: Geological and tectonic setting of Santorini
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R.S.J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 5-12
Santorini lies in an area of complex extensional and subduction-related tectonics in a continental environment (Jackson 1994). The region has had a long geological history with large changes occurring during the Alpine orogeny and in the Late Tertiary as a consequence of post-collisional extension and major re-adjustments of the plate...
Chapter 6 Geochemistry, isotopic composition and petrogenetic modelling of the Thera pyroclastics
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 89-116
This chapter examines the major element, trace element, and isotope geochemistry of the Thera pyroclastics, and places it in the context of the geochemical evolution of the whole volcanic field. Geochemical studies to date have been undertaken predominantly on the lavas, and the pyroclastic succession has been relatively neglected. The...
Chapter 3: Development of the Santorini volcanic field in space and time
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 13-59
Santorini is one of the largest Quaternary volcanic centres of the Aegean Region. The caldera cliffs preserve well-exposed sequences of lavas and pyroclastic deposits, which record the long development of the volcano in space and time. These include the products of 12 major explosive eruptions and the dissected remains of...
Chapter 5: Cumulate nodules in the Thera pyroclastics
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 79-88
Gabbroic and dioritic nodules are common in some horizons of the Thera pyroclastics. These nodules contain pyroxene as the main ferromagnesian phase in contrast to the early Akrotiri centre, which contain nodules with abundant hornblende (Nicholls 1971a; Pichler & Kussmaul 1972). Calcsilicate nodules and gabbroic nodules have also been recognized...
Chapter 1: Previous research
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 1-4
Santorini has fascinated and stimulated explorers and scholars since ancient times. Jason and the Argonauts were apparently visitors to the islands and described a giant called Talos. Molten metal flowed from his feet and he threw stones at them. The island is perhaps best known for the paroxysmal eruption that...
Appendix 2: Tabulated analytical data
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 138-163
Details of analytical methods and errors are given in Appendix 1. bd means below detection and na not analysed. Samples numbers which begin with the letter S are from Druitt (1983) and those that begin with LS are from Edwards (1994). Sample numbers which begin with the number 8 are either from Mellors (1988)...
Appendix 1: Analytical methods and errors
T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R.S.J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio
1999, Geological Society, London, Memoirs (19) 134-137
Thirty eight K-Ar and eight 40Ar/39Ar high-precision age determinations were made at the US Geological Survey, Menlo Park, on a total of 22 rocks from the entire volcanic field. Duplicate or triplicate determinations were carried out on 14 samples in order to improve analytical precision. All ages were measured on...
Role of brown bears (Ursus arctos) in the flow of marine nitrogen into a terrestrial ecosystem
Grant V. Hilderbrand, Thomas A. Hanley, Charles T. Robbins, C.C. Schwartz
1999, Oecologia (121) 546-550
We quantified the amount, spatial distribution, and importance of salmon (Oncorhynchus spp.)-derived nitrogen (N) by brown bears (Ursus arctos) on the Kenai Peninsula, Alaska. We tested and confirmed the hypothesis that the stable isotope signature (δ15N) of N in foliage of white spruce (Picea glauca)...
Robustness of closed capture-recapture methods to violations of the closure assumption
William L. Kendall
1999, Ecology (80) 2517-2525
Closed-population capture–recapture methods have been used extensively in animal ecology, both by themselves and within the context of Pollock’s robust design and multistate models, to estimate various parameters of population and community dynamics. The defining assumption of geographic and demographic closure (i.e., no births, deaths, immigration, or emigration) for the...
Evaluation of weights of evidence to predict epithermal-gold deposits in the Great Basin of the western United States
Gary L. Raines
1999, Natural Resources Research (8) 257-276
The weights-of-evidence method provides a simple approach to the integration of diverse geologic information. The application addressed is to construct a model that predicts the locations of epithermal-gold mineral deposits in the Great Basin of the western United States. Weights of evidence is a data-driven method requiring known deposits and...
Evaluation of factors that influence estimated zones of transport for six municipal wells in Clark County, Washington
L.L. Orzol, Margot Truini
1999, Water-Resources Investigations Report 97-4224
A ground-water flow model was used in conjunction with particle tracking to estimate zones of transport for six municipal well sites in Clark County, Washington. A zone of transport for a well is a three-dimensional volume within a ground-water system that contains all of the ground water that will discharge...