Integrated Ocean Drilling Program Expedition 347 aimed to retrieve sediments from different settings of the Baltic Sea, encompassing the last interglacial-glacial cycle to address scientific questions along four main research themes: 1. Climate and sea level dynamics of marine isotope Stage (MIS) 5, including onsets and terminations; 2. Complexities of the latest glacial, MIS 4-MIS 2; 3. Glacial and Holocene (MIS 2-MIS 1) climate forcing; and 4. Deep biosphere in Baltic Sea Basin (BSB) sediments. These objectives were accomplished by drilling in six subbasins: (1) the gateway of the BSB (Anholt), where we focused on sediments from MIS 6-5 and MIS 2-1; (2) a subbasin in the southwestern BSB (Little Belt) that possibly holds a unique MIS 5 record; (3, 4) two subbasins in the south (Bornholm Basin and Hanö Bay) that may hold long complete records from MIS 4-2; (5) a 450 m deep subbasin in the central Baltic (Landsort Deep) that promises to contain a thick and continuous record of the last ~14,000 y; and (6) a subbasin in the very north (Ångermanälven River estuary) that contains a uniquely varved (annually deposited) sediment record of the last 10,000 y. These six areas were expected to contain sediment sequences representative of the last ~140,000 y, with paleoenvironmental information relevant on a semicontinental scale because the Baltic Sea drains an area four times as large as the basin itself. The location of the BSB in the heartland of a recurrently waning and waxing ice sheet, the Scandinavian Ice Sheet, has resulted in a complex development: repeated glaciations of different magnitudes, sensitive responses to sea level and gateway threshold changes, large shifts in sedimentation patterns, and high sedimentation rates. Its position also makes it a unique link between Eurasian and northwest European terrestrial records. Therefore, the sediments of this largest European intracontinental basin form a rare archive of climate evolution over the latest glacial cycle. High sedimentation rates provide an excellent opportunity to reconstruct climatic variability of global importance at a unique resolution from a marine-brackish setting. Comparable sequences cannot be retrieved anywhere in the surrounding onshore regions. Furthermore, and crucially, the large variability (salinity, climate, sedimentation, and oxygenation) that the BSB has under
Integrated Ocean Drilling Program (IODP) Expedition 313 to the New Jersey Shallow Shelf off the east coast of the United States is the third IODP expedition to use a mission-specific platform. It was conducted by the European Consortium for Ocean Research Drilling (ECORD) Science Operator (ESO) between 30 April and 17 July 2009, with additional support from the International Continental Scientific Drilling Program (ICDP). There were three objectives: (1) date late Paleogene-Neogene depositional sequences and compare ages of unconformable surfaces that divide these sequences with times of sea level lowerings predicted from the δ 18 O glacio-eustatic proxy; (2) estimate the corresponding amplitudes, rates, and mechanisms of sea level change; and (3) evaluate sequence stratigraphic facies models that predict depositional environments, sediment compositions, and stratal geometries in response to sea level change. We drilled at three locations in around 35 m of water 45-67 km offshore, targeting the topsets, foresets, and toesets of several clinoforms at 180-750 meters below seafloor (mbsf). Seismic correlations to previously drilled holes on the continental slope and extrapolations of depths to key horizons in wells drilled into the adjacent coastal plain suggest the clinoform structures investigated during Expedition 313 were deposited during times of oscillations in global sea level; however, this needs to be determined with much greater certainty. The age, lithofacies, and core-log-seismic correlations provided by drilling at key locations will yield the data needed for a rigorous evaluation. We attempted 612 core runs with 80% recovery totaling 1311 m in length. Some or all of the upper 180-280 m of sand-prone sediment was drilled without coring. The deepest hole (M0029A) reached 757 mbsf, and the oldest sediment recovered was late Eocene (Hole M0027A). Wireline logs gathered spectral gamma ray, resistivity, magnetic susceptibility, sonic, and acoustic televiewer data; a vertical seismic profile was run at each site. Multisensor core logger (MSCL), natural gamma ray, and thermal conductivity measurements were made on all cores prior to splitting. Aided by physical properties of discrete samples measured onshore, we have established preliminary corelog-seismic ties with depth uncertainties typically ±7 m or less. We are confident that further study will narrow this range and firmly link facies successions to as many as 16 surfaces and/or sequence-bounding unconformities mapped in the regional seismic grid. Eight lithologic units are recognized that contain important Expedition 313 summary 1 Expedition 313 Scientists 2 Chapter contents
Integrated Ocean Drilling Program (IODP) Expedition 325, designed to investigate the fossil reefs on the shelf edge of the Great Barrier Reef, was the fourth expedition to utilize a mission-specific platform and was conducted by the European Consortium for Ocean Research Drilling (ECORD) Science Operator (ESO). The objectives of Expedition 325 were to establish the course of sea level change, define sea-surface temperature variations, and analyze the impact of these environmental changes on reef growth and geometry for the region over the period of 20-10 ka. To meet these objectives, a succession of fossil reef structures preserved on the shelf edge seaward of the modern barrier reef were cored from a dynamically positioned vessel in February-April 2010. A total of 34 boreholes across 17 sites were cored in depths ranging from 42.27 to 167.14 meters below sea level (lowest astronomical tide taken from corrected EM300 multibeam bathymetry data). Borehole logging operations in four boreholes provided continuous geophysical information about the drilled strata. The cores were described during the Onshore Science Party (OSP) at the IODP Bremen Core Repository (Germany) in July 2010, where minimum and some standard measurements were made. Preliminary postcruise dating of core catcher samples and initial observations of the cores made during the OSP confirm that coral reef material ranging in age from >30,000 to 9,000 calendar years before present (years before 1950 AD) was recovered during Expedition 325. Further postcruise research on samples taken during the OSP is expected to fulfill the objectives of the expedition.
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