A study for the long-term and short-term disturbances of the envirnment by the extraterrestrial impact at the Cretaceous/Tertiary boundary

白垩纪/第三纪边界外星撞击对环境的长期和短期扰动研究

• 批准号: 17403005
• 负责人: MATSUI Takafumi
• 金额: $ 9.52万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17403005/
• 关键词: Extraterrestrial impact; Cretaceous; Tertiary; Cuba; Tsunami; Mass extinction

We conducted field survey near the impact site at the Cretaceous/Tertiary (K/T) boundary at Fomento area, Cuba and Lajilla area, Mexico in order to investigate the magnitude and duration of the impact-induced tsunami. As a result, we found that the evidence of the crater-ward first tsunami wave is observed at Fomento area as well as the impactite in and out of the Chicxulub crater. These observations support the hypothesis that the tsunami was generated by the ocean water invasion into the crater and overflow from the crater.We also studied K/T boundary deposits and their adjacent deposits in central Cuba, Mexico, and New Zealand in order to study the long-term disturbance of the environment within one million years after the impact with a resolution of several thousand years. We found that n-C_<31>/(n-C_<29>+n-C_<31>) ratio and δ^<13>C_<wax> remarkably decreased just above the K/T boundary. In addition, the distributions of n-C_<31>/(n-C_<29>+n-C_<31>) ratio and δ^<13>C_<wax> were variable age by age. Especially, these values had positive correlation during early Paleocene, suggesting that carbon cycle disturbance and environmental change by the impact was recorded in terrestrial plants. We further studied the K/T boundary deposit at Lajilla, Mexico and correlated with Cuban deposits until 70 ka after the impact. In New Zealand, we obtained iridium-rich clay layer. Based on our study at Cuba, Mexico, and New Zealand, we could discuss the paleo-environmental change within 100 ka after the K/T boundary impact.

我们在古巴Fometo地区和墨西哥Lajilla地区白垩纪/第三系(K/T)交界处附近进行了实地调查，以调查由冲击引发的海啸的规模和持续时间。结果，我们发现，在福梅托地区以及奇克苏鲁布陨石坑内外的冲击岩中都观察到了向陨石坑方向移动的第一次海啸波的证据。我们还研究了古巴中部、墨西哥和新西兰的K/T边界沉积物及其邻近沉积物，以研究海啸发生后100万年内环境的长期扰动，分辨率为数千年。我们发现，n-C_&lt；31&gt；/(n-C_&lt；29&gt；+n-C_&lt；31&gt；)比和δ^&lt；13&gt；C_&lt；WAX&gt；显著降低的位置正好在K/T边界之上。此外，n-C_&lt；31&gt；/(n-C_&lt；29&gt；+n-C_&lt；31&gt；)比值和δ^&lt；13&gt；C_&lt；Ware&gt；尤其是在早古新世，这些值呈正相关，表明在陆生植物中记录了碳循环扰动和由此影响的环境变化。我们进一步研究了墨西哥Lajilla的K/T边界矿床，并与古巴的矿床进行了对比，直到撞击后的70ka。在新西兰，我们得到了富铱的粘土层。基于我们在古巴、墨西哥和新西兰的研究，我们可以讨论K/T边界撞击后100ka内的古环境变化。

项目成果

Generation and propagation of impact-induced tsunami at the Cretaceous/Tertiary boundary

白垩纪/第三纪边界撞击引起的海啸的产生和传播

• 发表时间: 2007
• 作者: Goto;K.
• 通讯作者: K.

キューバ中部ロマカピロの白亜紀/古第三紀境界上位層の年代と陸源バイオマーカーの変動

古巴中部洛马卡皮略上白垩纪/古近纪边界层的年龄和陆地生物标志物的变化

• 发表时间: 2006
• 作者: 山本真也;長谷川卓;多田隆治;後藤和久;Garcia-Delgado;D.;Diaz-Otero;C.;Rojas-Consuegra;R.;山本信治;佐久間広展;松井孝典
• 通讯作者: 松井孝典

PDF orientations in shocked quartz grains around the Chicxulub crater

希克苏鲁伯陨石坑周围受冲击石英颗粒的 PDF 方向

• 发表时间: 2008
• 期刊: Meteoritics & Planetary Science 43
• 作者: Nakano;Y.;Goto;K.;Matsui;T.;Tada;R.;Tajika;E.
• 通讯作者: E.

有機炭素同位体比から見た白亜紀/第三紀(K/T)境界イベント

从有机碳同位素比看白垩纪/第三纪（K/T）边界事件

• 发表时间: 2007
• 作者: 山本真也;長谷川卓;多田隆治;後藤和久;山本信治;佐久間広展;松井孝典
• 通讯作者: 松井孝典

Chicxulub tsunami deposits

希克苏鲁伯海啸沉积物

• 发表时间: 2006
• 作者: Matsui;T.;Tada;R.;Goto;K.
• 通讯作者: K.