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Aim: The deep waters around Iceland, known as the North Atlantic Gateway, constitute an ideal location to investigate deep-sea ecological hypotheses. We constructed a comprehensive deep-sea macroecological dataset of the North Atlantic Gateway region and investigated the controlling factors of large-scale, deep-sea species diversity patterns. Location: Sub-polar North Atlantic Ocean. Time period: Modern. Major taxa studied: Ostracoda (Crustacea). Methods: We investigated deep-sea biodiversity patterns and applied ecological modelling (multiple regression and model averaging) to test whether these patterns are governed by environmental factors such as temperature, surface primary productivity, and seasonality. Beta diversity analyses were applied to evaluate the effect of a geographical barrier (Greenland-Iceland-Faeroe Ridge) on deep-sea benthic faunal distributions. Results:We constructed a deep-sea macroecological dataset with 32 stations, 5,676 specimens, and >122 species. We confirmed a linear latitudinal diversity gradient with higher diversity in the North Atlantic proper than in the Nordic Seas. We report a unimodal depth diversity gradient south of the ridge, but a linear diversity-decline with depth north of the ridge. The turnover component of beta diversity increased towards the ridge. Main conclusions:We found both temperature and surface primary production are important for deep-sea biodiversity. For the first time, we report a significant diversity-temperature relationship in both macroecological (spatial; this study) and existing paleoecological (time-series) data for the same taxa. In addition to temperature and surface primary production, bathymetric features such as a shallow ridge acting as a barrier are an important factor for deep-sea biodiversity distribution. The low diversity of the Nordic Seas is likely due to a combination of low temperatures and bathymetric barriers. These results substantially expand our understanding of the | 2057 JÖST eT al.

Effective reef management and monitoring has become increasingly important as anthropogenic processes impact upon natural ecosystems. One locality that is under direct threat due to human activities is the Australian Great Barrier Reef (GBR). Marine foraminifera represent an abundant and readily applicable tool that can be used in reef studies to investigate a variety of ecological parameters and assist in understanding reef dynamics and influence management protocols. The first step is to establish a baseline knowledge of taxonomic composition within the region to facilitate comparative studies and monitor how assemblages change in order to maximise effective management. A detailed taxonomic assessment is provided of 133 species of benthic foraminifera in 76 genera from Heron Island, One Tree Island, Wistari and Sykes Reefs, which form the core of the Capricorn Group (CG) at the southern end of the GBR. Of these 133 species, 46% belong to the order Miliolida, 34% to Rotaliida, 7% to Textulariida, 5% to Lagenida, 3% to Lituolida, 3% to Spirillinida, 1% to Loftusiida and 1% to Robertinida. Samples were collected from a variety of shallow shelf reef environments including reef flat, lagoonal and channel environments. Seventy species, representing the most abundant forms, are formally described with detailed distribution data for the remaining 63 species supplied.

On March 11th, 2011 the Mw 9.0 2011 Tōhoku-Oki earthquake resulted in a tsunami which caused major devastation in coastal areas. Along the Japanese NE coast, tsunami waves reached maximum run-ups of 40 m, and travelled kilometers inland. Whereas devastation was clearly visible on land, underwater impact is much more difficult to assess. Here, we report unexpected results obtained during a research cruise targeting the seafloor off Shimokita (NE Japan), shortly (five months) after the disaster. The geography of the studied area is characterized by smooth coastline and a gradually descending shelf slope. Although high-energy tsunami waves caused major sediment reworking in shallow-water environments, investigated shelf ecosystems were characterized by surprisingly high benthic diversity and showed no evidence of mass mortality. Conversely, just beyond the shelf break, the benthic ecosystem was dominated by a low-diversity, opportunistic fauna indicating ongoing colonization of massive sand-bed deposits.

Site U1460 ended at 1945 h on 15 August. A total of 133 cores were recovered with the HLAPC system; of the 606.7 m cored, 592.2 m was recovered (recovery = 97%). Hole U1460A After arriving at Hole U1460A (27°22.4948′S, 112°55.4296′E), preparations for coring commenced. As a result of previous difficulty establishing the mudline core at Site U1459 (broken core barrel), the seafloor was tagged with the bit to determine its precise location and whether it was as hard as the previous site. A nonmagnetic HLAPC core barrel was dressed with a core liner, picked up, and run into the hole. Hole U1460A was started at 0115 h on 13 August. Based on the recovery of the mudline core, the seafloor depth was calculated to be 214.5 mbsl. Coring continued with the HLAPC system through Core 356-U1460A-64F to 298.2 m DSF. After the mudline core, each core was advanced 4.7 m despite partial strokes on Cores 2F, 9F, and 64F. Hole U1460A was cored to a final depth of 300.1 m DSF (Core 65F). During coring, a routine slip, cut, and retermination of the coring line was performed. At the conclusion of coring, the drill string was pulled back to 231.6 m DSF and the top drive was set back. The drill string was pulled back to just above the seafloor, clearing the seafloor at 0605 h on 14 August and ending Hole U1460A. Of 300.1 m cored, 291.39 m of material was recovered (recovery = 97.1%). The total time spent on Hole U1460A was 33.25 h. Hole U1460B After offsetting the vessel 20 m north of Hole U1460A, preparations were made to begin Hole U1460B (27°22.4867′S, 112°55.4265′E). A nonmagnetic HLAPC core barrel was dressed with a core liner, picked up, and run into the hole. Hole U1460B was started at 1920 h on 14 August. Based on the recovery of the mudline core, the seafloor depth was calculated to be 214.4 mbsl. Coring continued with the HLAPC system through Core 356-U1460B-68F to 306.6 m DSF. After the mudline core, each core was advanced by recovery in an attempt to cover any gaps from Hole U1460A. Of the 306.6 m cored, 800.81 m was recovered (recovery = 98%). Also in this hole, in situ temperature measurements were made with the APCT-3 before recovering Cores 12F, 20F, 28F, 33F, and 36F. During coring, a routine slip, cut, and retermination of the coring line was performed. At the conclusion of coring, the drill string was pulled back to 260.7 m DSF and the top drive was set back. The drill string was pulled from the hole and the advanced piston corer/extended core barrel bit cleared the rig floor at 1940 h. The thrusters and hydrophones were pulled and secured, and at 1945 h on 15 August, Site U1460 concluded. The total time spent on Hole U1460B was 37.75 h.

During an environmental survey, living (stained) benthic foraminiferal faunas were investigated at 14 stations within the Cassidaigne Canyon (NW Mediterranean Sea) and the surrounding area. For many decades, industrial bauxite residues (namely red mud) have drained into this canyon via a submarine pipe. Stations investigated in this paper are located between water depths of 288 and 2,432 m from the shelf break to the deeper basin and at a distance ranging between~5 and 70 km from the pipe outlet. At almost every site, surface sediment is characterized by red mud deposits and their geochemical imprints. Our ecological observations show that foraminiferal standing stocks and simple diversity (S) decrease across the margin in response to the decreasing food input to the seafloor with increasing water depth. The foraminiferal composition echoes the overall mesooligotrophic patterns of our study area. The contribution of opportunistic and stress-tolerant species, commonly identified as recolonizers of freshly disturbed areas, is minor at the 14 stations. This clearly shows that red mud dispersal in the Cassidaigne Canyon and the surrounding area has no major ecological impact on foraminiferal diversity.

Background and objectives 1 Operations 9 Lithostratigraphy 22 Biostratigraphy and micropaleontology 33 Geochemistry 36 Paleomagnetism 40 Physical properties 46 Downhole measurements 50 Stratigraphic correlation 64 References

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