Smith Vann, Warny Sophie, Jarzen David M, Demchuk Thomas, Vajda Vivi, Gulick Sean P S
Department of Geology and Geophysics, LSU, Baton Rouge, LA, USA.
Museum of Natural Science, LSU, Baton Rouge, LA, USA.
Palynology. 2020;44(3):489-519. doi: 10.1080/01916122.2019.1705417. Epub 2020 Jan 23.
At the end of the Cretaceous Period, an asteroid collided with the Earth and formed the Chicxulub impact structure on the Yucatán Platform. International Ocean Discovery Program (IODP) Expedition 364 drilled into the peak ring of the Chicxulub impact crater. The post-impact section of the core was sampled for terrestrial palynological analysis, yielding a high-resolution record ranging from the early Paleocene to the earliest Eocene (Ypresian), including a black shale deposited during the Paleocene-Eocene Thermal Maximum (PETM). The IODP 364 core provides the first record of floral recovery following the K-Pg mass extinction from inside the Chicxulub impact crater. The systematic taxonomy of the angiosperm pollen provided here follows a separate publication describing the systematic paleontology of the plant spores and gymnosperm pollen from the IODP 364 core (Smith et al. 2019). The Paleocene section of the core is nearly barren, but with unusually high relative abundances of the angiosperm pollen sp. A (comparable to the Amaranthaceae), possibly indicating an estuarine pollen source. Pollen recovery is higher in the PETM section, and variable but generally increasing in the later Ypresian section, with excellent preservation in several samples. Estimated absolute ages of several potentially useful regional biostratigraphic events are provided. One new genus () and five new species (, , , , and ) are formally described.
在白垩纪末期,一颗小行星与地球相撞,在尤卡坦平台形成了希克苏鲁伯撞击构造。国际大洋发现计划(IODP)364航次钻探进入了希克苏鲁伯撞击坑的峰环。对岩芯撞击后的部分进行了陆地孢粉学分析采样,得到了一个从早古新世到最早始新世(伊普雷斯阶)的高分辨率记录,包括在古新世-始新世极热事件(PETM)期间沉积的一层黑色页岩。IODP 364岩芯提供了希克苏鲁伯撞击坑内部白垩纪-古近纪生物大灭绝后植物群恢复的首个记录。这里提供的被子植物花粉的系统分类遵循了另一篇单独发表的论文所描述的IODP 364岩芯植物孢子和裸子植物花粉的系统古生物学(史密斯等人,2019年)。岩芯的古新世部分几乎没有花粉,但被子植物花粉sp. A的相对丰度异常高(与苋科相当),这可能表明是河口花粉来源。在PETM部分花粉回收率更高,在伊普雷斯阶后期部分则有所变化但总体上在增加,有几个样本保存完好。给出了几个潜在有用的区域生物地层事件的估计绝对年龄。正式描述了一个新属()和五个新物种(、、、、和)。