Collaborative Research: Paleomagnetic and Mineral Magnetic Characterization of Drill-Cores from the Cape Roberts Project (OSU Component)

摘要罗伯茨角项目（CRP）的目标是阐明从白垩纪到渐新世的冈瓦纳太平洋边缘破碎史和南极冰川史。CRP将在一个综合科学计划下运作，在连续两年的两个钻探季节，在南极的麦克默多站完成对岩心的所有初步科学表征。每个钻井季节将持续两个月，与海洋钻井计划的两个月巡航方式大致相同。与岩心表征相关的科学活动包括磁地层学、生物地层学、岩石学、矿物学和沉积学。在这样的项目中，年龄的确定是最重要的，因为时间框架对于获得气候和构造事件的历史是必要的。该奖项支持一项研究计划，该计划将能够确定高质量的古地磁地层学，并进行适当的矿物磁性研究，以支持CRP。对于现场磁学研究，该奖项将：进行全岩心磁化率的测井，这将有助于在CRP期间恢复的几个重叠岩心的相关性；确定磁地层格架用于岩心测年；进行矿物磁学和环境磁学研究，以评估古磁学信号的可靠性；并确定环境磁特性是否能提供有关构造、沉积学、成岩或气候变化对罗伯茨角沉积记录影响的信息。详细的环境和矿物磁学研究也将有助于评价作为地磁场记录者的沉积物。罗伯茨角记录提供了获得罕见的高纬度地磁场行为约束的潜力。古地磁研究还应提供有关罗斯海板块地壳运动和裂谷发育的重要数据。

Verosub OPP 9526889 Wilson OPP 9527343 Abstract The goals of the Cape Roberts Project (CRP) are to elucidate the history of fragmentation of the Pacific margin of Gondwana and the history of Antarctic glaciation from Cretaceous through Oligocene time. The CRP will operate with an integrated science plan in which all of the initial scientific characterization of the cores will be done at McMurdo Station in the Antarctic during two drilling seasons over two successive years. The drilling seasons will each be of two months duration and will operate in much the same manner as two month cruises of the Ocean Drilling Program. The scientific activities associated with characterization of the cores will include magnetostratigraphy, biostratigraphy, petrography, mineralogy, and sedimentology. Age determination is of principal importance in such a project because a temporal framework is necessary to obtain a history of climatic and tectonic events. This award supports a program of research which will enable determination of a high-quality paleomagnetic stratigraphy, with the appropriate mineral magnetic studies, in support of the CRP. For the on-site magnetic studies this award will: undertake logging of the whole-core magnetic susceptibility which will assist in correlation of the several overlapping cores to be recovered during the CRP; determine a magnetostratigraphic framework for dating of the cores; undertake mineral magnetic and environmental magnetic studies to assess the reliability of the paleomagnetic signal; and determine if environmental magnetic properties yield information concerning changes in the tectonic, sedimentologic, diagenetic or climatic influences on the sedimentary record at Cape Roberts. Detailed environmental and mineral magnetic studies will also enable evaluation of the sediments as recorders of the geomagnetic field. The Cape Roberts records provide the potential to obtain rare high southern latitude constraints on geomagne tic field behavior. Paleomagnetic studies should also provide important data concerning crustal movements and rift development in the Ross Sea sector.