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Full-Text Articles in Environmental Sciences
A High-Resolution, Multi-Channel, Over-Sea-Ice Seismic Reflection Survey Over The Mackay Sea Valley, Granite Harbor, Antarctica, B. Williams, Marvin Speece, Ross Powell
A High-Resolution, Multi-Channel, Over-Sea-Ice Seismic Reflection Survey Over The Mackay Sea Valley, Granite Harbor, Antarctica, B. Williams, Marvin Speece, Ross Powell
M. A Speece
In the austral summer of 2007, 20.5 km of high-resolution over-sea-ice seismic reflection data were collected in the Granite Harbor region of southern McMurdo Sound over the Mackay Sea Valley. The goal of the survey was to image thin pelagic sediment deposited in the Mackay Sea Valley after the Last Glacial Maximum. A generator–injector air gun was lowered beneath the sea ice through holes drilled by an auger drill system. The recording system was a 60 channel snow streamer with vertically oriented gimbaled geophones spaced 25 m apart. Unique problems in the over-sea-ice seismic reflection survey—noise from the ice column …
Downhole Measurements In The And-2a Borehole, Andrill Southern Mcmurdo Sound Project, Antarctica, T. Wonik, T. Grelle, D. Handwerger, R. D. Jarrard, A. Mckee, T. Patterson, T. Paulsen, S. Pierdominici, D. R. Schmitt, H. Schröder, M. Speece, T. Wilson
Downhole Measurements In The And-2a Borehole, Andrill Southern Mcmurdo Sound Project, Antarctica, T. Wonik, T. Grelle, D. Handwerger, R. D. Jarrard, A. Mckee, T. Patterson, T. Paulsen, S. Pierdominici, D. R. Schmitt, H. Schröder, M. Speece, T. Wilson
M. A Speece
Under the framework of the ANDRILL Southern McMurdo Sound (SMS) Project successful downhole experiments were conducted in the 1138.54 metre (m)-deep AND-2A borehole. Wireline logs successfully recorded were: magnetic susceptibility, spectral gamma ray, sonic velocity, borehole televiewer, neutron porosity, density, calliper, geochemistry, temperature and dipmeter. A resistivity tool and its backup both failed to operate, thus resistivity data were not collected. Due to hole conditions, logs were collected in several passes from the total depth at ~1138 metres below sea floor (mbsf) to ~230 mbsf, except for some intervals that were either inaccessible due to bridging or were shielded by …
Using New Tools To Explore Undiscovered Country: Understanding The Stratigraphic And Tectonic History Of Greenhouse To Icehouse Worlds Of Offshore New Harbor, Ross Sea, Antarctica, Stephan Pekar, M. A. Speece, D. M. Harwood, F. Florindo, G. S. Wilson
Using New Tools To Explore Undiscovered Country: Understanding The Stratigraphic And Tectonic History Of Greenhouse To Icehouse Worlds Of Offshore New Harbor, Ross Sea, Antarctica, Stephan Pekar, M. A. Speece, D. M. Harwood, F. Florindo, G. S. Wilson
M. A Speece
The Offshore New Harbor Project will investigate the stratigraphic and tectonic history of westernmost Southern McMurdo Sound. This will be used to address two widely recognized but unresolved issues regarding Antarctica’s history: 1) the mid-Paleogene cryospheric development on Antarctica; and 2) the abrupt climate shift across the Eocene/Oligocene transition. The first step for this project is to collect the requisite seismic and gravity data for identifying future drilling targets for the ANDRILL Program. ANDRILL is a multinational program, with the aim to recover stratigraphic intervals for interpreting Antarctica’s climate and glacial history over the past 50 million years. Offshore New …