BreakingNews·190912 - 小行星巖層揭示了恐龍是如何死亡的

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."

科學家說他們已經發(fā)現(xiàn)了6500萬年前恐龍是如何滅絕的細節(jié)。一個地球物理學家小組正在分析墨西哥附近海底火山口的巖層。巖石中含有一顆巨大的小行星撞擊地球后災難性后果的殘余物?？茖W家們說，他們提取的巖石層揭示了撞擊后巖石和沉淀物在暴露層中相互沉積而造成的破壞。普渡大學的地球物理學家杰伊·梅洛什說：“它告訴我們，在毀滅恐龍的那天，火山口內發(fā)生了什么。所有這些混亂都直接記錄在核心。”

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.

科學家說這顆小行星大約有3到4公里寬。它沖入海洋，形成了一個160公里寬20公里深的洞。這引發(fā)了地震、海嘯、冰蓋融化、山體滑坡和火災的連鎖反應，永遠改變了地球的地質和生命形式，殺死了恐龍。小行星的撞擊將巖石和礦物拋出，形成了一個巨大的隕石坑。熔巖又落回火山口，火山口隨后充滿了海嘯產生的海水。這片水域充滿了土壤、植被、動物生命和其他殘骸，所有這些都層層沉淀下來，供科學家在數(shù)百萬年后進行分析。科學家說這一層形成過程只花了幾個小時。