Preliminary Integrated Chronostratigraphy of the AND-1B Core, ANDRILL McMurdo Ice Shelf Project, Antarctica

• Main Authors: Wilson, G., Levy, R., Browne, G., Cody, R., Dunbar, N., Florindo, F., Herrys, S., Graham, I., McIntosh, W., McKay, R., Naish, T., Ohneiser, C., Powell, R., Ross, J., Sagnotti, L., Scherer, R., Sjunneskog, C., Strong, C. P., Taviani, M., Winter, D., the ANDRILL-MIS Science Team
• Other Authors: Wilson, G.; Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand, Levy, R.; ANDRILL Science Management Office, 126 Bessey Hall, University of Nebraska - Lincoln, Lincoln, NE 68588-0341 - USA, Browne, G.; GNS Science, PO Box 30368, Lower Hutt - New Zealand, Cody, R.; ANDRILL Science Management Office, 126 Bessey Hall, University of Nebraska - Lincoln, Lincoln, NE 68588-0341 - USA and GNS Science, PO Box 30368, Lower Hutt - New Zealand, Dunbar, N.; Earth and Environmental Science Department, New Mexico Institute of Technology, 801 Leroy Place, Socorro, NM 87801 - USA, Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Herrys, S.; GNS Science, PO Box 30368, Lower Hutt - New Zealand, Graham, I.; GNS Science, PO Box 30368, Lower Hutt - New Zealand, McIntosh, W.; Earth and Environmental Science Department, New Mexico Institute of Technology, 801 Leroy Place, Socorro, NM 87801 - USA, McKay, R.; Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington - New Zealand, Naish, T.; GNS Science, PO Box 30368, Lower Hutt - New Zealand and Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington - New Zealand, Ohneiser, C.; Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand, Powell, R.; Department of Geology and Environmental Geosciences, 312 Davis Hall, Normal Road, Northern Illinois University, De Kalb, IL 60115-2854 - USA, Ross, J.; Earth and Environmental Science Department, New Mexico Institute of Technology, 801 Leroy Place, Socorro, NM 87801 - USA, Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Scherer, R.; Department of Geology and Environmental Geosciences, 312 Davis Hall, Normal Road, Northern Illinois University, De Kalb, IL 60115-2854 - USA, Sjunneskog, C.; Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70803 - USA, Strong, C. P.; GNS Science, PO Box 30368, Lower Hutt - New Zealand, Taviani, M.; Istituto di Geologia Marina, CNR, Via Gobetti 101, I-40129 Bologna - Italy, Winter, D.; Department of Geosciences, University of Nebraska-Lincoln, Lincoln, NE 68588-0340 - USA, the ANDRILL-MIS Science Team; ANDRILL, Department of Geology, University of Otago, PO Box 56, Dunedin - New Zealand, ANDRILL Science Management Office, 126 Bessey Hall, University of Nebraska - Lincoln, Lincoln, NE 68588-0341 - USA, GNS Science, PO Box 30368, Lower Hutt - New Zealand, ANDRILL Science Management Office, 126 Bessey Hall, University of Nebraska - Lincoln, Lincoln, NE 68588-0341 - USA and GNS Science, PO Box 30368, Lower Hutt - New Zealand, #PLACEHOLDER_PARENT_METADATA_VALUE#, Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Earth and Environmental Science Department, New Mexico Institute of Technology, 801 Leroy Place, Socorro, NM 87801 - USA, Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington - New Zealand, GNS Science, PO Box 30368, Lower Hutt - New Zealand and Antarctic Research Centre, Victoria University of Wellington, PO Box 600, Wellington - New Zealand, Department of Geology and Environmental Geosciences, 312 Davis Hall, Normal Road, Northern Illinois University, De Kalb, IL 60115-2854 - USA, Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70803 - USA, Istituto di Geologia Marina, CNR, Via Gobetti 101, I-40129 Bologna - Italy, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, NE 68588-0340 - USA, ANDRILL
• Format: Article in Journal/Newspaper
• Language: English
• Published: Terra Antartica 2007
• Subjects: Chronostratigraphy; ANDRILL; Antarctica; 04. Solid Earth::04.05. Geomagnetism::04.05.06. Paleomagnetism; McMurdo Ice Shelf; Antarc*; Ice Shelf
• Online Access: http://hdl.handle.net/2122/3794

Chronostratigraphic data available for the preliminary age model for the upper 700 m for the AND-1B drill core include diatom biostratigraphy, magnetostratigraphy, 40Ar/39Ar ages on volcanic material, 87Sr/86Sr ages on calcareous fossil material, and surfaces of erosion identified from physical appearance and facies relationships recognised in the AND-1B drill core. The available age data allow a relatively well-constrained age model to be constructed for the upper 700 m of the drill core. Available diatom biostratigraphic constraints and 40Ar/39Ar ages allow a unique correlation of ~70% of the AND-1B magnetic polarity stratigraphy with the Geomagnetic Polar Time Scale (GPTS). Unique correlation is not possible in several coarse diamictite intervals with closely spaced glacial surfaces of erosion and sparse microflora. However, the age model indicates relatively rapid (up to 1 m/k.y.) and continuous accumulation of intervening finer grained diatomaceous intervals punctuated by several half- to million-years hiatuses representing more than half of the last 7 m.y. in the AND-1B record. The mid- to late Pleistocene is represented by superimposed diamictite units separated from upper Pliocene alternating diamictites/diatomites by a ~1 m.y. hiatus co-incident with a regionally correlated seismic reflection surface. A c. 100 m-thick diatomite represents a significant portion of the early Pliocene record in the AND-1B drill core. Strata below ~620 m are late Miocene in age; however, biostratigraphic constraints are absent below 586 m and correlation with the GPTS is relatively unconstrained. At the the of writing, the only chronostratigraphic data available below 700 mbsf include three 40Ar/39Ar ages on volcanic clasts from near 1280 mbsf affording a maximum depositional age of 13.57 Ma for the base of the AND-1B drill core. Published 297-316 2.2. Laboratorio di paleomagnetismo 3.8. Geofisica per l'ambiente N/A or not JCR reserved