The rock columns on the table are not much to look at. More than a
metre long, 10 centimetres in diameter and mostly made up of oil shale
and sandstone, they are a dull greyish green. But these, says Wang
Chengshan, a geologist at the China University of Geosciences in Beijing, "are not ordinary rocks".
Taken from depths of more than 2 kilometres into the Songliao Basin in northeastern China (see map), the rocks may hold clues to one of the strangest and most dynamic ages of Earth's history: the Cretaceous period. Beginning about 145 million years ago, the Cretaceous was the heyday of the dinosaurs. It was a time of climatic extremes, when global temperatures exceeded even the most alarming forecasts for the greenhouse world of 2100, and sea levels were up to 250 metres higher than today, covering about one-third of the current landmass. It was also a period of great geological and biological unrest, associated with frequent volcanic eruptions, the formation of major mountain ranges and ocean oxygen depletion. And it ended in spectacular style, with the global catastrophe that saw off dinosaurs some 65 million years ago, an event known as the Cretaceous/Palaeogene (K/Pg) extinction.
To read the full, original article click on this link: Geology: A trip to dinosaur time : Nature News
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