Radiometric dating sedimentary
Snelling also pointed to California's Kettleman Hills, where the natural gas is trapped between Miocene layers and overlying Pleistocene deposits.
Because for many species, humans included, evolution happens over the course of many thousands of years, it is rare to observe the process in a human lifetime.
It is commonly believed that these "fossil fuels" formed over millions of years after plant and animal remains were buried and then subjected to tremendous pressures. A recent article titled "Natural gas: A modern fuel millions of years in the making" reported that the refined gas used in barbecue grills "marks the last step in a process that began more than 500 million years ago." But that's not so.
Natural gas can be produced by adding heat and water to brown coal.
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co.
Coal, oil, and natural gas are precious earth materials that are used to power many modern human activities.