Magnetostratigraphy of Cretaceous Sediments in the James Ross Island Basin, Antarctica

Abstract: The PI will collect samples to extend the magneto-stratigraphic record of late Cretaceous sediments of the James Ross Basin, Antarctica. RAPID support will allow him to take advantage of an invitation from the Instituto Antartico Argentino (IAA) to participate on an excursion to James Ross Island in the Antarctic Peninsula. The PI hopes to collect samples that will refine the position of several geomagnetic reversals between the end of the Cretaceous long normal Chron and the lower portion of Chron 31R. The Brandy Bay locality targeted by this expedition is the best place in the basin for calibrating the biostratigraphic position of the top of the Cretaceous Long Normal Chron, which is one of the most reliable correlation horizons in the entire Geological Time Scale.

The top of the Cretaceous long normal Chron is not properly correlated to southern hemisphere biostratigraphy. Locating this event will be a major addition to understanding geological time. This expedition will provide opportunities for an undergraduate student. This project is based on a productive collaboration with an Argentine scientist.

摘要：项目负责人（Principal Investigator，PI）将采集样品，以拓展南极洲詹姆斯罗斯盆地（James Ross Basin）晚白垩世沉积物的磁地层学记录。RAPID资助将使其得以利用阿根廷南极研究所（Instituto Antartico Argentino，IAA）的邀请，参与前往南极半岛（Antarctic Peninsula）詹姆斯罗斯岛（James Ross Island）的野外考察。该项目负责人计划采集的样品将精准厘清白垩纪超长正极性时结束至31R极性时（Chron 31R）之间的多次地磁倒转位置。本次科考瞄准的布兰迪湾采样点，是该盆地中用于校准白垩纪超长正极性时顶界生物地层位置的最佳点位——该顶界是全球地质年代表（Geological Time Scale）中最可靠的地层对比标志层之一。

目前白垩纪超长正极性时的顶界尚未与南半球生物地层学建立准确的地层对应关系。厘定该事件的位置将为地质年代学研究提供重要补充。本次科考将为一名本科生提供科研参与机会。本项目基于与一名阿根廷科学家的富有成效的合作。