TYTAN

High-resolution multichannel seismic profiles have been collected in January–March 2017 by OGS on the continental rise off the Sabrina Coast (East Antarctica). The data were acquired as part of the Italian Program of Antarctic Research (PNRA) TYTAN “Totten Glacier dynamics and Southern Ocean circulation impact on depositional processes since the Mid- to Late Cenozoic” project (PI: F. Donda-OGS) during the Australian Marine National Facility survey IN2017-V01 on board the RV Investigator. TYTAN was embedded in to the Australian project "Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles” that aimed to understand the interaction of Totten Glacier and its ice drainage basin with the Southern Ocean during periods of warming and ice-sheet retreat in the Pleistocene and Holocene. In order to achieve these scientific objectives, three areas were identified for the geophysical and oceanographic survey: two on the continental slope and rise off Sabrina Coast and one on the continental shelf, which was not investigated because it remained covered by sea ice throughout the season. Expanded and well-preserved sedimentary successions imaged on the TYTAN seismic data highlight the potential of this region for deep ocean drilling, which will provide unprecedented history of the glaciers evolution in the Aurora Basin and their sensitivity to climate change under different background state conditions. In fact, TYTAN seismic data played a crucial role in the identification of potential drilling sites for the IODP 1002 Proposal “Totten Glacier Climate Vulnerability under varying Neogene climate conditions: Lessons for East Antarctic Ice Sheet climate sensitivity” (under review).

2017年1-3月，意大利地球物理研究所（OGS）在东南极洲（East Antarctica）萨布里娜海岸外的大陆隆（continental rise）区域采集了高分辨率多道地震剖面（high-resolution multichannel seismic profiles）。本次数据采集作为意大利南极研究计划（Italian Program of Antarctic Research, PNRA）TYTAN项目的一部分开展，该项目主题为“晚新生代以来托滕冰川动力学与南大洋环流对沉积过程的影响”，项目首席研究员（Principal Investigator, PI）为F. Donda-OGS，作业依托澳大利亚海洋国家设施（Australian Marine National Facility）的“探索者号”科考船（RV Investigator），参与航次为IN2017-V01。TYTAN项目被纳入澳大利亚项目“多冰期尺度下托滕冰川与南大洋的相互作用”，该项目旨在探究更新世（Pleistocene）与全新世（Holocene）气候变暖及冰盖退缩时期，托滕冰川及其冰川流域与南大洋之间的相互作用机制。为达成上述科学目标，本次地球物理与海洋学调查划定了三个作业区域：萨布里娜海岸外的大陆坡（continental slope）与大陆隆区域各1处，以及大陆架（continental shelf）区域1处；但由于该大陆架区域在整个航季始终被海冰覆盖，未能开展调查作业。TYTAN地震数据所成像的展布范围广泛且保存完好的沉积序列（sedimentary successions），凸显了该区域开展深海钻探（deep ocean drilling）的潜力——本次钻探将获取极光盆地（Aurora Basin）冰川演化的前所未有的完整记录，以及不同背景气候状态下冰川对气候变化的敏感性响应。事实上，TYTAN地震数据在国际大洋发现计划（International Ocean Discovery Program, IODP）1002号提案"Totten Glacier Climate Vulnerability under varying Neogene climate conditions: Lessons for East Antarctic Ice Sheet climate sensitivity"（审稿中）的潜在钻探点位遴选工作中发挥了关键作用。