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Andrill’S Success During The 4th International Polar Year, Fabio Florindo, David M. Harwood, Richard Levy, Sms Project Science Team
Andrill’S Success During The 4th International Polar Year, Fabio Florindo, David M. Harwood, Richard Levy, Sms Project Science Team
ANDRILL Research and Publications
One of the scientific programs of the Fourth International Polar Year (Allison et al., 2007;www.ipy.org), the ANDRILL (ANtarctic geological DRILLing) Program demonstrated ability to recover high quality marine and glacimarine sedimentary drill cores from high latitude ice-covered areas. ANDRILL’s inaugural 2006 and 2007 drilling seasons resulted in the two deepest drill holes on the Antarctic continental margin, recovering 2,400 meters of high-quality and nearly continuous sediment core. A chief scientific objective of this collaborative effort of scientists, engineers, technicians, students, educators, drillers and support personnel from Germany, Italy, New Zealand, and the United States is the recovery of sedimentary archives …
Sediment Cores Reveal Antarctica’S Warmer Past, Quirin Schiermeier
Sediment Cores Reveal Antarctica’S Warmer Past, Quirin Schiermeier
ANDRILL Research and Publications
A unique drilling project in the western Ross Sea has revealed that Antarctica had a much more eventful climate history than previously assumed. A new sediment core hints that the western part of the now-frozen continent went through prolonged ice-free phases — presumably offering a glimpse of where our warming world might be heading. Researchers reported initial results from ANDRILL, a US$30-million international drilling project, on April 16 at the assembly of the European Geosciences Union in Vienna. During the past two years, the team has extracted two cores, each containing some 1,200 meters of sediment, from the seabed below …
Preliminary Integrated Chronostratigraphy Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, G. Acton, J. Crampton, G. Di Vincenzo, Christopher R. Fielding, F. Florindo, M. Hannah, D. M. Harwood, S. Ishman, K. Johnson, L. Jovane, Richard Levy, B. Lum, M. C. Marcano, S. Mukasa, C. Ohneiser, M. P. Olney, C. Riesselman, L. Sagnotti, C. Stefano, E. Strada, M. Taviani, E. Tuzzi, K. L. Verosub, G. S. Wilson, M. Zattin, Andrill-Sms Science Team
Preliminary Integrated Chronostratigraphy Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, G. Acton, J. Crampton, G. Di Vincenzo, Christopher R. Fielding, F. Florindo, M. Hannah, D. M. Harwood, S. Ishman, K. Johnson, L. Jovane, Richard Levy, B. Lum, M. C. Marcano, S. Mukasa, C. Ohneiser, M. P. Olney, C. Riesselman, L. Sagnotti, C. Stefano, E. Strada, M. Taviani, E. Tuzzi, K. L. Verosub, G. S. Wilson, M. Zattin, Andrill-Sms Science Team
ANDRILL Research and Publications
We use all available chronostratigraphic constraints – biostratigraphy, magnetostratigraphy, radioisotopic dates, strontium-isotope stratigraphy, and correlation of compositional and physical properties to well-dated global or regional records – to construct a preliminary age model for ANDRILL SMS Project’s AND-2A drillcore (77°45.488’S, 165°16.605’E, 383.57 m water depth). These diverse chronostratigraphic constraints are consistent with each other and are distributed throughout the 1138.54 m-thick section, resulting in a well-constrained age model. The sedimentary succession comprises a thick early and middle Miocene section below 224.82 mbsf and a condensed middle/late Miocene to Recent section above this. The youngest sediments are Brunhes age (<0.781 Ma), as confirmed by a radioisotopic age of 0.691±0.049 Ma at 10.23 mbsf and the occurrence of sediments that have normal magnetic polarity down to ~31.1 mbsf, which is interpreted to be the Brunhes/Matuyama reversal (0.781 Ma). The upper section is punctuated by disconformities resulting from both discontinuous deposition and periods of extensive erosion typical of sedimentary environments at the margin of a dynamic ice sheet. Additional breaks in the section may be due to the influence of tectonic processes. The age model incorporates several major hiatuses but their precise depths are still somewhat uncertain, as there are a large number of erosional surfaces identified within the stratigraphic section. One or more hiatuses, which represent a total 7 to 8 million years of time missing from the sedimentary record, occur between about 50 mbsf and the base of Lithostratigraphic Unit (LSU) 3 at 122.86 mbsf. Similarly, between about 145 mbsf and the base of LSU 4 at 224.82 mbsf, one or more hiatuses occur on which another 2 to 3 million years of the sedimentary record is missing. Support for the presence of these hiatuses comes from a diatom assemblage that constrains the age of the core from 44 to 50 mbsf to 2.06-2.84 Ma, two radioisotopic dates (11.4 Ma) and a Sr‑isotope date (11.7 Ma) that indicate the interval from 127 to 145 mbsf was deposited between 11.4 and 11.7 Ma, and three diatom occurrence datums from between 225.38 and 278.55 mbsf that constrain the age of this upper part of Lithostratigraphic Unit (LSU) 5 to 14.29 - 15.89 Ma. Below the boundary between LSU 5 and 6 sedimentation was relatively continuous and rapid and the age model is well-constrained by 9 diatom datums, seven 40 …
Operations Overview For The Andrill Southern Mcmurdo Sound Project, Antarctica, T. Falconer, A. Pyne, D. Wilson, Richard Levy, S. Nielsen, S. Petrushak, Andrill-Sms Science Team
Operations Overview For The Andrill Southern Mcmurdo Sound Project, Antarctica, T. Falconer, A. Pyne, D. Wilson, Richard Levy, S. Nielsen, S. Petrushak, Andrill-Sms Science Team
ANDRILL Research and Publications
During the austral spring of 2007-08, a 1138 metre (m)-long rock and sediment core (ANDRILL [AND]-2A) was recovered from beneath the land-fast sea-ice in southern McMurdo Sound (SMS) in 384 m of water. A custom-built drilling system comprising an UDR-1200 rig, jack-up platform, hot water drill, sea riser, and diamond-bit wireline coring string was set up on the sea-ice approximately 32 kilometres (km) from Scott Base (NZ) and McMurdo Station (USA). The drilling system employed technology developed to handle challenging environmental conditions, including drilling from an 8 metre-thick sea-ice ‘platform’ that moved both laterally and vertically, tidal currents, and high …
Physical Properties Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, Gavin B. Dunbar, C. Atkins, D. Magens, F. Niessen, Andrill-Sms Science Team
Physical Properties Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, Gavin B. Dunbar, C. Atkins, D. Magens, F. Niessen, Andrill-Sms Science Team
ANDRILL Research and Publications
Whole-core measurements of Wet Bulk Density (WBD), compressional (P)-wave velocity (Vp), and Magnetic Susceptibility were measured at a sampling interval of 1 or 2 centimetres (cm) throughout the AND-2A drill core for initial core characterisation and on-site correlation with seismic modeling to predict target-reflector depth. Measurements were made using a GEOTEK (Multi-Sensor-Core-Logger MSCL). Density and velocity standards were measured together with core runs of 3-6 metres (m) (and occasionally up to 18 m) throughout the entire depth range to monitor data quality. Drift of the magnetic susceptibility sensor was also monitored and corrected where necessary. These physical properties show a …
Palaeomagnetism Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, G. Acton, F. Florindo, L. Jovane, B. Lum, C. Ohneiser, L. Sagnotti, E. Strada, K. L. Verosub, G. S. Wilson, Andrill-Sms Science Team
Palaeomagnetism Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, G. Acton, F. Florindo, L. Jovane, B. Lum, C. Ohneiser, L. Sagnotti, E. Strada, K. L. Verosub, G. S. Wilson, Andrill-Sms Science Team
ANDRILL Research and Publications
We conducted initial palaeomagnetic studies on cores from site AND-2A (77°45.488’S, 165°16.605’E, ~383.57 metres water depth). A total of 813 samples were collected that span from the top of the section down to the base at 1138.54 metres below sea floor (mbsf). Samples were collected every one or two metres down the core, with paired (pilot) samples being collected about every ten to twenty metres to allow us to assess the demagnetisation behaviour of the samples using either alternating field (AF) or thermal demagnetisation. With the exception of only a few intervals, AF demagnetisation was observed to resolve a characteristic …
Sedimentology And Stratigraphy Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, Christopher R. Fielding, C. B. Atkins, K. N. Bassett, G. H. Browne, G. B. Dunbar, B. D. Field, Tracy D. Frank, L. A. Krissek, K. S. Panter, S. Passchier, S. F. Pekar, S. Sandroni, F. Talarico, Andrill-Sms Science Team
Sedimentology And Stratigraphy Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, Christopher R. Fielding, C. B. Atkins, K. N. Bassett, G. H. Browne, G. B. Dunbar, B. D. Field, Tracy D. Frank, L. A. Krissek, K. S. Panter, S. Passchier, S. F. Pekar, S. Sandroni, F. Talarico, Andrill-Sms Science Team
ANDRILL Research and Publications
During the 2007 – 2008 austral spring season, the ANDRILL Southern McMurdo Sound Project recovered a core 1138 metres long (AND-2A) from a location in the southern McMurdo Sound near the Dailey Islands. This core contains a range of lithologies, including various types of terrigenous clastic diamictite, conglomerate and breccia, sandstone and mudrocks, volcanic lava, pyroclastic and reworked volcanic sedimentary rocks, and diatomite. The succession is divided into fourteen lithostratigraphic units (LSUs), two of which (LSUs 1 and 8) are further subdivided into three and four sub-units, respectively, based on changes in abundance of lithologies. Thirteen lithofacies are recognized, ranging …
Explanatory Notes For The Andrill Southern Mcmurdo Sound Project, Antarctica, F. Florindo, D. M. Harwood, Richard Levy, G. Acton, Christopher R. Fielding, K. Panter, T. Paulsen, F. Sangiorgi, F. Talarico, M. Taviani, V. Willmott, Andrill-Sms Science Team
Explanatory Notes For The Andrill Southern Mcmurdo Sound Project, Antarctica, F. Florindo, D. M. Harwood, Richard Levy, G. Acton, Christopher R. Fielding, K. Panter, T. Paulsen, F. Sangiorgi, F. Talarico, M. Taviani, V. Willmott, Andrill-Sms Science Team
ANDRILL Research and Publications
This Explanatory Notes section complements and supports four other documents, which collectively describe the process and procedures of scientific investigations employed during the ANDRILL SMS Project: (1) ANDRILL Southern McMurdo Sound Project - Scientific Prospectus (ANDRILL contribution 5 - Harwood et al., 2005); (2) a Science Plan summary of SMS Project research compiled from research proposals of Science Team menbers (available on the SMS Project ‘Science Drive’ – Harwood et al., 2007); (3) SMS Project Science Logistics Implementation Plan (SLIP) - draft documents developed and distributed to SMS team members prior to deployment; (4) Operations overview – Falconer et al., …
Late Cenozoic Climate History Of The Ross Embayment From The And-1b Drill Hole: Culmination Of Three Decades Of Antarctic Margin Drilling, T. R. Naish, R. D. Powell, Peter J. Barrett, R. H. Levy, S. Henrys, G. S. Wilson, L. A. Krissek, F. Niessen, M. Pompilio, J. Ross, R. Scherer, F. Talarico, A. R. Pyne, Andrill-Mis Science Team
Late Cenozoic Climate History Of The Ross Embayment From The And-1b Drill Hole: Culmination Of Three Decades Of Antarctic Margin Drilling, T. R. Naish, R. D. Powell, Peter J. Barrett, R. H. Levy, S. Henrys, G. S. Wilson, L. A. Krissek, F. Niessen, M. Pompilio, J. Ross, R. Scherer, F. Talarico, A. R. Pyne, Andrill-Mis Science Team
ANDRILL Research and Publications
Because of the paucity of exposed rock, the direct physical record of Antarctic Cenozoic glacial history has become known only recently and then largely from offshore shelf basins through seismic surveys and drilling. The number of holes on the continental shelf has been small and largely confined to three areas (McMurdo Sound, Prydz Bay, and Antarctic Peninsula), but even in McMurdo Sound, where Oligocene and early Miocene strata are well cored, the late Cenozoic is poorly known and dated. The latest Antarctic geological drilling program, ANDRILL, successfully cored a 1285-m-long record of climate history spanning the last 13 m.y. from …
Fracture Logging Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, T. Paulsen, C. Millan, S. Pierdominici, T. J. Wilson, S. Drew, Andrill-Sms Science Team
Fracture Logging Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, T. Paulsen, C. Millan, S. Pierdominici, T. J. Wilson, S. Drew, Andrill-Sms Science Team
ANDRILL Research and Publications
Fractures in AND-2A drillcore were documented in this study. Over 4100 fractures of all types were logged. A population of 510 steeply-dipping, petal, petal-centreline and core-edge induced fractures is present, reaching a maximum density of c. 10 fractures/metre. Subhorizontal induced extension fractures are also abundant. There are 1008 natural fractures in the core, including faults, brecciated zones, veins and sedimentary intrusions. Kinematic indicators document dominant normal faulting, although reverse faults are also present. The natural fractures occur in strata ranging in age from the Miocene to the Plio-Pleistocene.
Background To The Andrill Southern Mcmurdo Sound Project, Antarctica, F. Florindo, D. M. Harwood, F. Talarico, Richard Levy
Background To The Andrill Southern Mcmurdo Sound Project, Antarctica, F. Florindo, D. M. Harwood, F. Talarico, Richard Levy
ANDRILL Research and Publications
During the austral spring of 2007, the Southern McMurdo (SMS) Project recovered a 1138.54 meter long drill core (AND-2A) from a 8.5 m thick floating seaice platform (~8.5 meters thick) over approximately 380 meters of water (77°45.488S; 165°16.613E) (Fig. 1). This demonstrated the ANDRILL Program’s continuing success in recovering high quality marine and glacimarine sedimentary drill core (> 98% core recovery) from high latitude ice-covered areas. A primary goal of the SMS Project, the second drillhole
of the McMurdo Sound Portfolio (Harwood et al., 2006), was to recover an Antarctic marine sediment record depositied during the middle Miocene, which has …
Petrologic And Geochemical Composition Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, K. Panter, F. Talarico, K. Bassett, P. Del Carlo, B. Field, T. Frank, S. Hoffmann, G. Kuhn, L. Reichelt, S. Sandroni, M. Taviani, L. Bracciali, G. Cornamusini, H. Von Eynatten, S. Rocchi, Andrill-Sms Science Team
Petrologic And Geochemical Composition Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, K. Panter, F. Talarico, K. Bassett, P. Del Carlo, B. Field, T. Frank, S. Hoffmann, G. Kuhn, L. Reichelt, S. Sandroni, M. Taviani, L. Bracciali, G. Cornamusini, H. Von Eynatten, S. Rocchi, Andrill-Sms Science Team
ANDRILL Research and Publications
The compositional record of the AND-2A drillcore is examined using petrological, sedimentological, volcanological and geochemical analysis of clasts, sediments and pore waters. Preliminary investigations of basement clasts (granitoids and metasediments) indicate both local and distal sources corresponding to variable ice-volume and ice-flow directions. Low abundance of sedimentary clasts (e.g., arkose, litharenite) suggests reduced contributions from sedimentary covers while intraclasts (e.g., diamictite, conglomerate) attest to intrabasinal reworking. Volcanic material includes pyroclasts (e.g., pumice, scoria), sediments and lava. Primary and reworked tephra layers occur within the Early Miocene interval (1093 to 640 metres below sea floor). …
Palaeontological Characterisation And Analysis Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, M. Taviani, M. Hannah, D. M. Harwood, S. E. Ishman, K. Johnson, M. Olney, C. Riesselman, E. Tuzzi, A. G. Beu, S. Blair, V. Cantarelli, A. Ceregato, S. Corrado, B. Mohr, S. H.H. Nielson, D. Persico, S. Petrushak, J. I. Raine, S. Warny, Andrill-Sms Science Team
Palaeontological Characterisation And Analysis Of The And-2a Core, Andrill Southern Mcmurdo Sound Project, Antarctica, M. Taviani, M. Hannah, D. M. Harwood, S. E. Ishman, K. Johnson, M. Olney, C. Riesselman, E. Tuzzi, A. G. Beu, S. Blair, V. Cantarelli, A. Ceregato, S. Corrado, B. Mohr, S. H.H. Nielson, D. Persico, S. Petrushak, J. I. Raine, S. Warny, Andrill-Sms Science Team
ANDRILL Research and Publications
The palaeontological yield of the 1138.54 metre-long AND-2A sedimentary rock core provides unique documentation of Neogene environments in the Ross Sea region of Antarctica. Especially important is the biological legacy of the climatically crucial ‘mild’ middle Miocene phase. Diatom-bearing units provide key information for stratigraphic intervals never previously recovered from locations proximal to the Antarctic continent and constrain the age model for the AND-2A core. Benthic calcareous (and agglutinated) foraminifera were present at many levels; remarkable is the occurrence of planktonic taxa only seldom found in the Neogene nearshore record of the Ross Sea region. The sporadic occurrence of calcareous …
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. J. Wilson, Andrill-Sms Science Team
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. J. Wilson, Andrill-Sms Science Team
ANDRILL Research and Publications
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 …
Andrill’S Education And Outreach Programme 2005‑2008: Mis And Sms Project Activities During The 4th Ipy, L. T. Huffman, Richard Levy, Laura Lacy, D. M. Harwood, M. Berg, M. Cattadori, J. Diamond, J. Dooley, L. Dahlman, R. Frisch-Gleason, J. Hubbard, R. Lehmann, K. Mankoff, V. Miller, K. Pound, F. R. Rack, G. Scotto Di Clemente, A. Seigmund, J. Thomson, E. Trummel, R. Williams, Andrill-Mis Science Team, Andrill-Sms Science Team
Andrill’S Education And Outreach Programme 2005‑2008: Mis And Sms Project Activities During The 4th Ipy, L. T. Huffman, Richard Levy, Laura Lacy, D. M. Harwood, M. Berg, M. Cattadori, J. Diamond, J. Dooley, L. Dahlman, R. Frisch-Gleason, J. Hubbard, R. Lehmann, K. Mankoff, V. Miller, K. Pound, F. R. Rack, G. Scotto Di Clemente, A. Seigmund, J. Thomson, E. Trummel, R. Williams, Andrill-Mis Science Team, Andrill-Sms Science Team
ANDRILL Research and Publications
A key goal of the ANDRILL programme’s education and outreach (E&O) activities was to engage the public in, and inform it about, our scientific endeavour to uncover the behavior of Antarctica’s ice sheets over the past 20 million years. We recognized that a critical component of ANDRILL’s research effort was to ensure that our motivation, methods, and results were conveyed to non-experts in a clear and understandable manner. This effort benefited from several factors: a synergy between scientists and educators generated by the 4th International Polar Year (IPY); the allure of the Antarctic region as one of Earth’s few …