By extracting oxygen, and carbon isotopes from the sediment and analyzing their chemical make-up, geochemists can deduce temperature, humidity, and even weather conditions from prehistoric world.

通过在沉积层里提取氧和碳的同位素，并且分析其化学构成，地化学家能够推测出温度、湿度、甚至是史前世界的气候条件。