BreakingNews·190912 - 小行星岩层揭示了恐龙是如何死亡的

Scientists say they have unearthed details of how the dinosaurs were wiped out 65 million years ago. A team of geophysicists is analyzing rock formations in a crater under the seabed off Mexico. The rocks contain the remnants of the cataclysmic aftermath of a gigantic asteroid impacting with Earth. The scientists say the layers of rock they have extracted reveal a step-by-step account of the destruction that happened after the impact as rock and sediment settled on top of each other in revealing layers. Geophysicist Jay Melosh from Purdue University said: "It tells us what went on inside the crater on that day of doom that killed the dinosaurs. All of this mayhem is directly recorded in the core."

科学家说他们已经发现了6500万年前恐龙是如何灭绝的细节。一个地球物理学家小组正在分析墨西哥附近海底火山口的岩层。岩石中含有一颗巨大的小行星撞击地球后灾难性后果的残余物。科学家们说，他们提取的岩石层揭示了撞击后岩石和沉淀物在暴露层中相互沉积而造成的破坏。普渡大学的地球物理学家杰伊·梅洛什说：“它告诉我们，在毁灭恐龙的那天，火山口内发生了什么。所有这些混乱都直接记录在核心。”

Scientists say the asteroid was around three to four kilometers wide. It smashed into the ocean and created a hole 160kms wide and 20kms deep. This triggered a chain reaction of earthquakes, tsunami, icecap melting, landslides and fires that forever changed the geology and life forms on Earth, killing off the dinosaurs. The asteroid's impact hurled out rock and minerals and created a massive crater. Molten rock fell back into the crater, which was then filled with ocean water from tidal waves. This water was full of soil, vegetation, animal life and other debris, all of which settled in layers ready for scientists to analyze millions of years later. The scientists say this layer-forming process took just a few hours.

科学家说这颗小行星大约有3到4公里宽。它冲入海洋，形成了一个160公里宽20公里深的洞。这引发了地震、海啸、冰盖融化、山体滑坡和火灾的连锁反应，永远改变了地球的地质和生命形式，杀死了恐龙。小行星的撞击将岩石和矿物抛出，形成了一个巨大的陨石坑。熔岩又落回火山口，火山口随后充满了海啸产生的海水。这片水域充满了土壤、植被、动物生命和其他残骸，所有这些都层层沉淀下来，供科学家在数百万年后进行分析。科学家说这一层形成过程只花了几个小时。