ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Collection
Keywords
Publisher
Language
Years
  • 1
    facet.materialart.
    Unknown
    Re-evaluation of heat flow data near Parkfield, CA: Evidence for a weak San Andreas Fault (2004)
    In:  Geophys. Res. Lett., Karlsruhe, 3-4, vol. 31, no. 15, pp. 582, pp. L15S15, (ISBN: 0534351875, 2nd edition)
    Details
    Publication Date: 2004
    Keywords: Geothermics ; Strength ; Borehole geophys. ; SAF ; Fault zone ; Earthquake precursor: prediction research ; SAFOD ; ICDP ; Fluids ; Stress ; GRL
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BIBLIOGRAPHY SEISMOLOGY
  • 2
    facet.materialart.
    Unknown
    Heat flow along the Costa Rica seismogenesis project drilling transect: Implications for hydrothermal and seismic processes (2016)
    Wiley
    Details
    Publication Date: 2016-05-11
    Description: Heat flow analysis of the Costa Rica convergent margin is carried out for seven sites drilled during Integrated Ocean Drilling Program (IODP) Expeditions 334 and 344 as part of the Costa Rica Seismogenesis Project (CRISP). These expeditions are designed to better understand erosional subduction zones. Heat flow measurements were made to improve estimates of the thermal structure of this erosive margin and are located on the incoming plate, toe, lower, middle, and upper slopes of the margin. Heat flow values corrected for the effects of seafloor bathymetry and sedimentation are on average 15% higher than uncorrected values and range from approximately 158 to 200 mW/m 2 on the incoming plate to values of approximately 50 mW/m 2 on the middle and upper slopes of the margin. These values are consistent with previous estimates of heat flow showing a landward decrease in heat flow consistent with the subduction the Cocos plate. Preferred thermal models of the shallow subduction zone successfully predicting observed values of heat flow incorporate fluid flow within the upper oceanic aquifer have an uppermost permeability of 10 −9.5 m 2 and a plate boundary effective coefficient of friction of 0.06. These models suggest that temperatures on the subduction thrust reach 100° C at distances between 30 and 35 km landward of the deformation front. The updip limit of seismicity, as defined by aftershocks events of M L 1-4 recorded following the Mw 6.9 Quepos earthquake, occurs at 25 km landward of the deformation front at temperatures cooler than the 100-150°C typically predicted. This article is protected by copyright. All rights reserved.
    Electronic ISSN: 1525-2027
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Contemporary Ocean Warming Dissociates Cascadia Margin Gas Hydrates (2014)
    Wiley
    Details
    Publication Date: 2014-11-05
    Description: Gas hydrates, pervasive in continental margin sediments, are expected to release methane in response to ocean warming, but the geographic range of dissociation and subsequent flux of methane to the ocean are not well constrained. Sediment column thermal models based on observed water column warming trends offshore Washington (USA) show that a substantial volume of gas hydrate along the entire Cascadia upper continental slope is vulnerable to modern climate change. Dissociation along the Washington sector of the Cascadia margin alone has the potential to release 45–80 Tg of methane by 2100. These results highlight the importance of lower latitude warming to global gas hydrate dynamics and suggest that contemporary warming and downslope retreat of the gas hydrate reservoir occurs along a larger fraction of continental margins worldwide than previously recognized.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Dust, volcanic ash, and the evolution of the South Pacific Gyre through the Cenozoic (2015)
    Wiley
    Details
    Publication Date: 2015-07-15
    Description: We examine the 0-100 Ma paleoceanographic record retained in pelagic clay from the South Pacific Gyre (SPG) by analyzing 47 major, trace, and rare earth elements in bulk sediment in 206 samples from seven sites drilled during Integrated Ocean Drilling Program Expedition 329. We use multivariate statistical analyses (Q-mode factor analysis and multiple linear regression) of the geochemical data to construct a model of bulk pelagic clay composition and mass accumulation rates (MAR) of six end-members, (post-Archean average Australian shale (PAAS), rhyolite, basalt, Fe-Mn-oxyhydroxides, apatite, and excess Si). Integrating the results with Co-based age models at Sites U1365, U1366, U1369, and U1370, we link changes in MAR of these components to global oceanographic, terrestrial, and climatic transformations through the Cenozoic. Our results track the spatial extent (1000s of kms) of dust deposition in the SPG during the aridification of Australia. Dispersed ash is a significant component of the pelagic clay, often comprising 〉50% by mass, and records episodes of Southern Hemisphere volcanism. Because both are transported by wind, the correlation of dust and ash MAR depends on the site's latitude and suggests meridional shifts in the position of atmospheric circulation cells. The hydrothermal MARs provide evidence for rapid deposition from the Osbourn Trough spreading ridge before it went extinct. Excess Si MARs show the abrupt increase in siliceous productivity observed at Site U1371 also extended at least as far north as Sites U1369 and U1370, suggesting large scale reorganizations of oceanic Si distributions ~10-8 Ma in the southern SPG.
    Print ISSN: 0883-8305
    Electronic ISSN: 1944-9186
    Topics: Geosciences
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Heat flow in vapor dominated areas of the Yellowstone Plateau Volcanic Field: Implications for the thermal budget of the Yellowstone Caldera (2012)
    Wiley
    Details
    Publication Date: 2012-10-13
    Description: Characterizing the vigor of magmatic activity in Yellowstone requires knowledge of the mechanisms and rates of heat transport between magma and the ground surface. We present results from a heat flow study in two vapor dominated, acid-sulfate thermal areas in the Yellowstone Caldera, the 0.11 km2 Obsidian Pool Thermal Area (OPTA) and the 0.25 km2 Solfatara Plateau Thermal Area (SPTA). Conductive heat flux through a low permeability layer capping large vapor reservoirs is calculated from soil temperature measurements at 〉600 locations and from laboratory measurements of soil properties. The conductive heat output is 3.6 ± 0.4 MW and 7.5 ± 0.4 MW from the OPTA and the SPTA, respectively. The advective heat output from soils is 1.3 ± 0.3 MW and 1.2 ± 0.3 MW from the OPTA and the SPTA, respectively and the heat output from thermal pools in the OPTA is 6.8 ± 1.4 MW. These estimates result in a total heat output of 11.8 ± 1.4 MW and 8.8 ± 0.4 MW from OPTA and SPTA, respectively. Focused zones of high heat flux in both thermal areas are roughly aligned with regional faults suggesting that faults in both areas serve as conduits for the rising acid vapor. Extrapolation of the average heat flux from the OPTA (103 ± 2 W·m−2) and SPTA (35 ± 3 W·m−2) to the ∼35 km2 of vapor dominated areas in Yellowstone yields 3.6 and 1.2 GW, respectively, which is less than the total heat output transported by steam from the Yellowstone Caldera as estimated by the chloride inventory method (4.0 to 8.0 GW).
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    Observations and Modeling of a Hydrothermal Plume in Yellowstone Lake (2019)
    Wiley
    Details
    Publication Date: 2019
    Description: Abstract Acoustic Doppler current profiler and conductivity‐temperature‐depth data acquired in Yellowstone Lake reveal the presence of a buoyant plume above the “Deep Hole” hydrothermal system, located southeast of Stevenson Island. Distributed venting in the ~200 × 200‐m hydrothermal field creates a plume with vertical velocities of ~10 cm/s in the mid‐water column. Salinity profiles indicate that during the period of strong summer stratification the plume rises to a neutral buoyancy horizon at ~45‐m depth, corresponding to a ~70‐m rise height, where it generates an anomaly of ~5% (−0.0014 psu) relative to background lake water. We simulate the plume with a numerical model and find that a heat flux of 28 MW reproduces the salinity and vertical velocity observations, corresponding to a mass flux of 1.4 × 103 kg/s. When observational uncertainties are considered, the heat flux could range between 20 to 50 MW.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Presence of oxygen and aerobic communities from sea floor to basement in deep-sea sediments (2015)
    Springer Nature
    Details
    Publication Date: 2015-04-01
    Description: Nature Geoscience 8, 299 (2015). doi:10.1038/ngeo2387 Authors: Steven D’Hondt, Fumio Inagaki, Carlos Alvarez Zarikian, Lewis J. Abrams, Nathalie Dubois, Tim Engelhardt, Helen Evans, Timothy Ferdelman, Britta Gribsholt, Robert N. Harris, Bryce W. Hoppie, Jung-Ho Hyun, Jens Kallmeyer, Jinwook Kim, Jill E. Lynch, Claire C. McKinley, Satoshi Mitsunobu, Yuki Morono, Richard W. Murray, Robert Pockalny, Justine Sauvage, Takaya Shimono, Fumito Shiraishi, David C. Smith, Christopher E. Smith-Duque, Arthur J. Spivack, Bjorn Olav Steinsbu, Yohey Suzuki, Michal Szpak, Laurent Toffin, Goichiro Uramoto, Yasuhiko T. Yamaguchi, Guo-liang Zhang, Xiao-Hua Zhang & Wiebke Ziebis The depth of oxygen penetration into marine sediments differs considerably from one region to another. In areas with high rates of microbial respiration, O2 penetrates only millimetres to centimetres into the sediments, but active anaerobic microbial communities are present in sediments hundreds of metres or more below the sea floor. In areas with low sedimentary respiration, O2 penetrates much deeper but the depth to which microbial communities persist was previously unknown. The sediments underlying the South Pacific Gyre exhibit extremely low areal rates of respiration. Here we show that, in this region, microbial cells and aerobic respiration persist through the entire sediment sequence to depths of at least 75 metres below sea floor. Based on the Redfield stoichiometry of dissolved O2 and nitrate, we suggest that net aerobic respiration in these sediments is coupled to oxidation of marine organic matter. We identify a relationship of O2 penetration depth to sedimentation rate and sediment thickness. Extrapolating this relationship, we suggest that oxygen and aerobic communities may occur throughout the entire sediment sequence in 15–44% of the Pacific and 9–37% of the global sea floor. Subduction of the sediment and basalt from these regions is a source of oxidized material to the mantle.
    Print ISSN: 1752-0894
    Electronic ISSN: 1752-0908
    Topics: Geosciences
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Heat flow along the NanTroSEIZE transect: Results from IODP Expeditions 315 and 316 offshore the Kii Peninsula, Japan (2011)
    Wiley
    Details
    Publication Date: 2011-08-23
    Description: We report detailed thermal measurements undertaken during Integrated Ocean Drilling Program (IODP) Expeditions 315 and 316 along the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) transect offshore the Kii Peninsula, Japan. Geothermal objectives included determining thermophysical rock properties of the cored material and characterizing the background thermal regime along this transect. New thermal conductivity measurements made with a divided bar are reported and supplement shipboard full- and half-space thermal conductivity measurements for a total of 938 thermal conductivity measurements. Thermal conductivity varies between about 1.0 W m−1 K−1 near the seafloor to 1.6 W m−1 K−1 at a depth of 1 km. Thermal conductivity generally increases with depth and correlates with variations in porosity and lithology. Thermal gradients along the transect are characterized by 48 sediment temperature measurements from 6 sites. Thermal corrections for the effects of bathymetric relief and sedimentation improve the confidence with which the heat flow values can be interpreted. Heat flow generally decreases with landward distance from the deformation front and varies from 70 mW m−2 just landward of the deformation front to 54 mW m−2 at sites characterizing the outer fore-arc high and to 57 mW m−2 at the Kumano Basin Site. IODP heat flow measurements are significantly lower than nearby seafloor heat flow measurements. This difference is most likely due to variations in bottom water temperature that have a large effect on values of seafloor heat flow. Thus the heat flow of the Nankai accretionary prism is lower than previously thought. We present thermal models of subduction along this transect and explore the impact of the initial geotherm. Conductive plate cooling based on the age of subducting seafloor (20 Myr) under predicts the observed heat flow. We find a good fit to the data using a geotherm appropriate for 10 Myr seafloor. The extra heat is interpreted in terms of back-arc thermal environments.
    Electronic ISSN: 1525-2027
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    Heat flow bounds over the Cascadia margin derived from bottom simulating reflectors and implications for thermal Models of subduction (2017)
    Wiley
    Details
    Publication Date: 2017-08-13
    Description: Understanding the thermal structure of the Cascadia subduction zone is important for understanding megathrust earthquake processes and seismogenic potential. Currently our understanding of the thermal structure of Cascadia is limited by a lack of high spatial resolution heat flow data and by poor understanding of thermal processes such as hydrothermal fluid circulation in the subducting basement, sediment thickening and dewatering, and frictional heat generation on the plate boundary. Here, using a dataset of publically available seismic lines combined with new interpretations of bottom simulating reflector (BSR) distributions, we derive heat flow estimates across the Cascadia margin. Thermal models that account for hydrothermal circulation predict BSR-derived heat flow bounds better than purely conductive models, but still over-predict surface heat flows. We show that when the thermal effects of in-situ sedimentation and of sediment thickening and dewatering due to accretion are included, models with hydrothermal circulation become consistent with our BSR-derived heat flow bounds.
    Electronic ISSN: 1525-2027
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Heat Flow and Fluid Flux in Cascadia's Seismogenic Zone (2013)
    Wiley
    Details
    Publication Date: 2013-11-27
    Description: The Cascadia Subduction Zone in the northeast Pacific has generated a large number of megathrust earthquakes and poses the greatest recognized seismic hazard to the northwestern United States. To learn more about the risks this subduction zone poses, scientists from Washington and Oregon conducted a research cruise in August aboard the R/V Atlantis to collect data that would estimate the thermal structure of the “fully locked zone” of the Cascadia megathrust fault. This locked zone resists the continuous motion of two tectonic plates as they collide, storing compressional energy that produces large megathrust earthquakes when released by the abrupt failure of the locking process.
    Print ISSN: 0096-3941
    Electronic ISSN: 2324-9250
    Topics: Geosciences
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...