Options
Brachfeld, S.
Loading...
Preferred name
Brachfeld, S.
2 results
Now showing 1 - 2 of 2
- PublicationRestrictedIron oxide tracers of ice sheet extent and sediment provenance in the ANDRILL AND-1B drill core, Ross Sea, Antarctica(2013-11)
; ; ; ; ; ; ; ; ; ; ;Brachfeld, S.; Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA ;Pinzon, J.; Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA ;Darley, J.; Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA ;Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Kuhn, G.; Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Alten Hafen 26, D-27568 Bremerhaven, Germany ;Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Wilson, G.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand ;Ohneiser, C.; Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand ;Monien, D.; Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Alten Hafen 26, D-27568 Bremerhaven, Germany ;Joseph, L.; Department of Environmental Studies, Ursinus College, Collegeville, PA 19426, USA; ; ; ; ; ; ; ; ; The AND-1B drill core recovered a 13.57 million year Miocene through Pleistocene record from beneath the McMurdo Ice Shelf in Antarctica (77.9°S, 167.1°E). Varying sedimentary facies in the 1285 m core indicate glacial–interglacial cyclicity with the proximity of ice at the site ranging from grounding of ice in 917 m of water to ice free marine conditions. Broader interpretation of climatic conditions of the wider Ross Sea Embayment is deduced from provenance studies. Here we present an analysis of the iron oxide assemblages in the AND-1B core and interpret their variability with respect to wider paleoclimatic conditions. The core is naturally divided into an upper and lower succession by an expanded 170 m thick volcanic interval between 590 and 760 m. Above 590 m the Plio-Pleistocene glacial cycles are diatom rich and below 760 m late Miocene glacial cycles are terrigenous. Electron microscopy and rock magnetic parameters confirm the subdivision with biogenic silica diluting the terrigenous input (fine pseudo-single domain and stable single domain titanomagnetite from the McMurdo Volcanic Group with a variety of textures and compositions) above 590 m. Below 760 m, the Miocene section consists of coarse-grained ilmenite and multidomain magnetite derived from Transantarctic Mountain lithologies. This may reflect ice flow patterns and the absence of McMurdo Volcanic Group volcanic centers or indicate that volcanic centers had not yet grown to a significant size. The combined rock magnetic and electron microscopy signatures of magnetic minerals serve as provenance tracers in both ice proximal and distal sedimentary units, aiding in the study of ice sheet extent and dynamics, and the identification of ice rafted debris sources and dispersal patterns in the Ross Sea sector of Antarctica.280 55 - PublicationRestrictedNeogene tectonic and climatic evolution of the Western Ross Sea, Antarctica — Chronology of events from the AND-1B drill hole(2012-10)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Wilson, G. S.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand ;Levy, R. H.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand ;Naish, T. R.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Powell, R. D.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, IL 60115, USA ;Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Ohneiser, C.; Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand ;Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Winter, D. M.; ANDRILL Science Management Office, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, NE 68588‐0340, USA ;Cody, R.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Henrys, S.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand ;Ross, J.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, NM 87801, USA ;Krissek, L.; Byrd Polar Research Centre, The Ohio State University, Columbus, OH 43210, USA ;Niessen, F.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany ;Pompillio, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia ;Scherer, R.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, IL 60115, USA ;Alloway, B. V.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Barrett, P. J.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Brachfeld, S.; Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA ;Browne, G.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand ;Carter, L.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Cowan, E.; Department of Geology, Appalachian State University, Boone, NC 28608‐2067, USA ;Crampton, J.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand ;DeConto, R. M.; Department of Geosciences, University of Massachusetts, Amherst, MA 01003‐9297, USA ;Dunbar, G.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Dunbar, N.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand ;Dunbar, R.; Department of Environmental Earth System Sciences, School of Earth Sciences, Stanford University, Stanford, CA 94305, USA ;von Eynatten, H.; Department of Sedimentology and Environmental Geology, Geoscience Center Göttingen (GZG), Goldschmidtstrasse 3, Göttingen, Germany ;Gebhardt, C.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany ;Giorgetti, G.; Dipartimento di Scienze della Terra, Universita di Sienna, Via Laterina 8, I-53100, Sienna, Italy ;Graham, I.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand ;Hannah, M.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Hansaraj, D.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Harwood, D. M.; ANDRILL Science Management Office, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, NE 68588‐0340, USA ;Hinnov, L.; Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, USA ;Jarrard, R. D.; Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112, USA ;Joseph, L.; Environmental Studies Program, Ursinus College, Collegeville, PA 19426, USA ;Kominz, M.; Department of Geology, Western Michigan University, Kalamazoo, MI 49008, USA ;Kuhn, G.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany ;Kyle, P.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, NM 87801, USA ;Läufer, A.; Federal Institute for Geosciences & Natural Resources, BGR, Stilleweg 2, D-30655 Hannover, Germany ;McIntosh, W. C.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, NM 87801, USA ;McKay, R.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington, New Zealand ;Maffioli, P.; Università Milano-Bicocca, Dipartimento di Scienze Geologiche e Geotecnologie, Piazza della Scienza 4, I-20126 Milano, Italy ;Magens, D.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany ;Millan, C.; Byrd Polar Research Centre, The Ohio State University, Columbus, OH 43210, USA ;Monien, D.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515, Bremerhaven, Germany ;Morin, R.; US Geological Survey, Mail Stop 403, Denver Federal Center, Denver, CO 80225, USA ;Paulsen, T.; Department of Geology, University of Wisconsin, Oshkosh, 800 WI 54901, USA ;Persico, D.; Departimento di Scienze della Terra, Universita di Parma, Parco Aeres delle Scienze, 157 Parma, Italy ;Pollard, D.; Earth and Environmental Systems Institute, 2217 Earth-Engineering Science Bldg, University Park, PA 16802, USA ;Raine, J. I.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand ;Riesselman, C.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand ;Sandroni, S.; Dipartimento di Scienze della Terra, Universita di Sienna, Via Laterina 8, I-53100, Sienna, Italy ;Schmitt, D.; Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand ;Sjunneskog, C.; Antarctic Marine Geology Research Facility, Department of Geology, Florida State University, Tallahassee, FL 32306, USA ;Strong, C. P.; GNS Science, PO Box 30‐368, Lower Hutt, New Zealand ;Talarico, F.; Dipartimento di Scienze della Terra, Universita di Sienna, Via Laterina 8, I-53100, Sienna, Italy ;Taviani, M.; CNR, ISMAR — Bologna, Via Gobetti 101, I-40129 Bologna, Italy ;Villa, G.; Departimento di Scienze della Terra, Universita di Parma, Parco Aeres delle Scienze, 157 Parma, Italy ;Vogel, S.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, IL 60115, USA ;Wilch, T.; Albion College, Department of Geology, Albion, MI 49224, USA ;Williams, T.; Columbia University, Lamont-Doherty Earth Observatory, Palisades, NY 10964, USA ;Wilson, T. J.; Byrd Polar Research Centre, The Ohio State University, Columbus, OH 43210, USA ;Wise, S.; Antarctic Marine Geology Research Facility, Department of Geology, Florida State University, Tallahassee, FL 32306, USA; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; Stratigraphic drilling from the McMurdo Ice Shelf in the 2006/2007 austral summer recovered a 1284.87 m sedimentary succession from beneath the sea floor. Key age data for the core include magnetic polarity stratigraphy for the entire succession, diatom biostratigraphy for the upper 600 m and 40Ar/39Ar ages for in-situ volcanic deposits as well as reworked volcanic clasts. A vertical seismic profile for the drill hole allows correlation between the drill hole and a regional seismic network and inference of age constraint by correlation with well‐dated regional volcanic events through direct recognition of interlayered volcanic deposits as well as by inference from flexural loading of pre‐existing strata. The combined age model implies relatively rapid (1 m/2–5 ky) accumulation of sediment punctuated by hiatuses, which account for approximately 50% of the record. Three of the longer hiatuses coincide with basin‐wide seismic reflectors and, along with two thick volcanic intervals, they subdivide the succession into seven chronostratigraphic intervals with characteristic facies: 1. The base of the cored succession (1275–1220 mbsf) comprises middle Miocene volcaniclastic sandstone dated at approx 13.5 Ma by several reworked volcanic clasts; 2. A late-Miocene sub-polar orbitally controlled glacial–interglacial succession (1220–760 mbsf) bounded by two unconformities correlated with basin‐wide reflectors associated with early development of the terror rift; 3. A late Miocene volcanigenic succession (760–596 mbsf) terminating with a ~1 my hiatus at 596.35 mbsf which spans the Miocene–Pliocene boundary and is not recognised in regional seismic data; 4. An early Pliocene obliquity-controlled alternating diamictite and diatomite glacial–interglacial succession(590–440 mbsf), separated from; 5. A late Pliocene obliquity-controlled alternating diamictite and diatomite glacial–interglacial succession (440–150 mbsf) by a 750 ky unconformity interpreted to represent a major sequence boundary at other locations; 6. An early Pleistocene interbedded volcanic, diamictite and diatomite succession (150–80 mbsf), and; 7. A late Pleistocene glacigene succession (80–0 mbsf) comprising diamictite dominated sedimentary cycles deposited in a polar environment.485 63