دانلود کتاب Cataclysms: A New Geology for the Twenty-First Century

In 1980, the science world was stunned when a maverick team of researchers proposed that a massive meteor strike had wiped the dinosaurs and other fauna from the Earth 66 million years ago. Scientists found evidence for this theory in a "crater of doom" on the Yucat�n Peninsula, showing that our planet had once been a target in a galactic shooting gallery. InCataclysms, Michael R. Rampino builds on the latest findings from leading geoscientists to take "neocatastrophism" a step further, toward a richer understanding of the science behind major planetary upheavals and extinction events.Rampino recounts his conversion to the impact hypothesis, describing his visits to meteor-strike sites and his review of the existing geological record. The new geology he outlines explicitly rejects nineteenth-century "uniformitarianism," which casts planetary change as gradual and driven by processes we can see at work today. Rampino offers a cosmic context for Earth's geologic evolution, in which cataclysms from above in the form of comet and asteroid impacts and from below in the form of huge outpourings of lava in flood-basalt eruptions have led to severe and even catastrophic changes to the Earth's surface. This new geology sees Earth's position in our solar system and galaxy as the keys to understanding our planet's geology and history of life. Rampino concludes with a controversial consideration of dark matter's potential as a triggering mechanism, exploring its role in heating Earth's core and spurring massive volcanism throughout geologic time.