Collaborative Proposal: SHALDRIL - A Demonstration Drilling Cruise to the James Ross Basin

该奖项由极地方案办公室南极地质学和地球物理学方案提供，为一个示范项目提供资金，以证明基于船舶的浅层地质钻探的可行性，同时收集有用的岩心，以评估南极冰盖的早期历史。三十多年来，美国科学家及其国际同事在南极洲边缘沿着的浅海架和海洋进行探索时，一直因无法穿透在这些地形上浅的次底层深度（上部10米以内）遇到的过度压实的冰川杂岩而感到沮丧。这是特别令人沮丧的，因为先进的高分辨率地震反射技术清楚地表明，在许多地区存在的新第三纪，甚至古第三纪序列的老继承躺在这个薄单板的杂岩。在恢复这些序列的方法被开发出来之前，南极冰盖的详细历史，这是了解新生代古气候和全球范围内未来气候变化的必要先决条件，将仍然是一个难以捉摸和无法实现的目标。在一名专业工程师的帮助下，经过四年的研究和评估（以及两个研讨会的过程），SHALDRIL委员会，一个感兴趣的美国科学家团体，已经确定了至少两个钻石取芯系统，被认为适用于现有的破冰美国南极研究计划船只。本项目的目标是在RV/IB Nathaniel B上采用金刚石取芯技术。帕尔默，以测试和证明船基金刚石取芯和井下测井的可行性。在这次“示范航行”中，将尝试在南极半岛西摩岛附近大陆架上沿沿着高分辨率地震反射剖面取芯，西摩岛本身就是一个具有高度科学意义的地区。在这里，定义明确的地质剖面估计年龄范围从始新世到第四纪，有效地跨越了南极/全球气候演变中的“温室-冰室”过渡。在南极边缘的沿着，还没有关于这种转变的完整记录。在岩心回收之后，该项目将使新岩心的古气候记录与最近结束的基于坚冰的罗伯茨角项目在罗斯海东部高纬度记录的冰缘详细波动相关联。如果成功的话，这个移动的灵活的钻探系统将可供更广泛的科学界进一步研究古环境条件和其他科学领域，这些领域目前受到美国南极计划在探索海岸线/固定冰边缘和大陆坡之间的南极大陆架的技术能力方面存在的差距的阻碍。SHALDRIL将能够在“无人区”有效地作业，该无人区目前存在于近海岸（基于坚冰的罗伯茨角项目取得成功的地方）和上斜坡（海洋钻探计划的船只JOIDES Resolution变得最有效的地方）之间。这一技术突破不仅可以解决过去三十年来重大的突出科学问题，而且还将对目前美国和SCAR（ICSU南极研究科学委员会）的许多南极或钻探相关计划产生有利影响，如WAIS，ANTIME，ANDRILL，ANTEC，ICOND，PAGES，GLOCHANT（包括PICE），MARGINS，ODP和STRATAFORM。

This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, provides funds for a demonstration project to prove the viability of shallow ship-based geological drilling while simultaneously collecting useful cores for assessing the early history of the Antarctic ice sheets. For over three decades, U.S. scientists and their international colleagues exploring the shallow shelves and seas along the margins of Antarctic have been consistently frustrated by their inability to penetrate through the over-compacted glacial diamictons encountered at shallow sub bottom depths (within the upper 10 m) over these terrains. This is particularly frustrating because advanced high resolution seismic reflection techniques clearly show in many areas the presence of older successions of Neogene and even Paleogene sequences lying just beneath this thin veneer of diamictons. Until the means are developed to recover these sequences, a detailed history of the Antarctic ice sheets, which is an essential prerequisite to understanding Cenozoic paleoclimate and future climate change on a global scale, will remain an elusive and unobtainable goal. After four years of study and evaluation with the aid of a professional engineer (and over the course of two workshops), the SHALDRIL Committee, an interested group of U.S. scientists, has identified at least two diamond-coring systems deemed suitable for use on existing ice-breaking U.S. Antarctic Research Program vessels. The goal of this project is to employ diamond-coring technology on the RV/IB Nathaniel B. Palmer in order to test out and demonstrate the feasibility of both ship-based diamond coring and down-hole logging. For this "demonstration cruise" coring will be attempted along a high-resolution seismic reflection profile on the continental shelf adjacent to Seymour Island, Antarctic Peninsula, an area of high scientific interest in its own right. Here the well-defined geologic section is estimated to range from Eocene to Quaternary in age, effectively spanning the "Greenhouse-Icehouse" transition in the evolution of Antarctic/global climate. A complete record of this transition has yet to be obtained anywhere along the Antarctic margin. Following core recovery, this project will result in correlation of the paleoclimate records from the new cores with detailed fluctuations of the ice margin recorded at higher latitudes in the eastern Ross Sea by the recently concluded, fast-ice-based Cape Roberts Project. If successful, this mobile and flexible drilling system will then be available to the broader scientific community for further research in paleoenvironmental conditions and other areas of science that are currently hindered by the present gap that exists in the US Antarctic Program's technical capability to explore the Antarctic shelves between the shore-line/fast-ice margin and the continental slope. SHALDRIL will be able to operate effectively in the "no man's land" that presently exists between the near shore (where the fast-ice-based Cape Roberts Project was successful) and the upper slope (where the Ocean Drilling Program's vessel JOIDES Resolution becomes most efficient). This technological breakthrough will not only allow major outstanding scientific problems of the last three decades to be addressed, but will also favorably impact many current U.S. and SCAR (ICSU Scientific Committee on Antarctic Research) Antarctic or drilling-related initiatives, such as WAIS, ANTIME, ANDRILL, ANTEC, IMAGES, PAGES, GLOCHANT (including PICE), MARGINS, ODP, and STRATAFORM.