Vegetation dynamics along the New Jersey margin (ODP Leg 174AX) in the context of Late Maastrichtian and Cretaceous-Palaeogene boundary paleo-environmental changes

白垩纪-古近纪界线（K/Pg; 65.0Ma）大灭绝事件是导致海洋和陆地生态系统中主要动物群和植物群发生重大逆转的五大灭绝事件之一。在陆地植物区系中，K/Pg边界事件表现为被子植物的灭绝和先锋植物（如蕨类植物）的增殖，这些植物可能在希克苏鲁布（墨西哥）的火流星撞击后的几千年里在世界范围内占据主导地位。另外，有人认为印度德干圈闭的脱气是最近马斯特里赫特变暖脉冲背后的主要驱动力，最终导致K/Pg边界生态系统的崩溃。植被重建的马斯特里赫特的高分辨率孢粉分析的基础上，可以提供重要的信息的强度，持续时间和灭绝事件之前的环境变化的原因。沿着新泽西边缘的一个岸外断面钻探的一系列岩心是在ODP 174 AX航次和大陆动力学计划的框架内钻探的，这些岩心为研究马斯特里赫特期到丹尼期的植被变化提供了一个独特的档案。预计将对巴斯河、安科拉、搜索农场、梅尔斯农场和Tighe公园的钻孔进行高分辨率的孢粉分析。该项目旨在（1）记录新泽西边缘沿着蕨类植物穗间隔的存在，（2）更好地了解马斯特里赫特植被对德干圈闭释放的CO2引发的变暖脉冲的反应，（3）通过将陆地数据纳入基于甲藻孢囊的高分辨率生物地层框架，实现陆海相关性，（4）将植被变化与基于TEX 86代用数据重建的古温度进行对比。

The Cretaceous-Palaeogene boundary (K/Pg; 65.0 Ma) mass-extinction event is one of the so-called Big Five extinctions that led to major faunal and floral overturn in marine and terrestrial ecosystems. In terrestrial floras the K/Pg boundary event is expressed by the extinction of angiosperms and the proliferation of pioneer plants, such as ferns, that likely dominated worldwide for several thousand years after the impact of a bolide at Chicxulub (Mexico). Alternatively, it has been suggested that the degassing of the Deccan Traps in India was a major driving force behind pulses of latest Maastrichtian warming, leading eventually to the collapse of ecosystems at the K/Pg boundary. Vegetation reconstructions of the Maastrichtian based on high-resolution palynological analyses could provide important information about the intensity, duration, and causes of environmental changes prior to the extinction event. A series of cores drilled along an onshore-offshore transect on the New Jersey margin drilled in the framework of ODP Leg 174AX and the Continental Dynamics Program provide an unique archive to study Maastrichtian to Danian vegetation changes. High-resolution palynological analyes are foreseen for the Bass River, Ancora, Search Farm, Meirs Farm, and Tighe Park boreholes. The project aims to (1) document the presence of fern spike intervals along the New Jersey margin, (2) better understand the response of Maastrichtian vegetation to warming pulses triggered by the release of CO2 from the Deccan Traps, (3) achieve land-sea correlations by incorporating the terrestrial data in a highresolution biostratigraphic framework based on dinoflagellate cysts, (4) compare vegetation changes with paleotemperature reconstructions based on the TEX86 proxy.