The 366 daily episodes in 2014 were chronological snapshots of earth history, beginning with the Precambrian in January and on to the Cenozoic in December. You can find them all in the index in the right sidebar. In 2015, the daily episodes for each month were assembled into monthly packages, and a few new episodes were posted. Now, the blog/podcast is on a weekly schedule with diverse topics, and the Facebook Page showcases photos on Mineral Monday and Fossil Friday. Thanks for your interest!

Sunday, June 1, 2014

June 1. The Carboniferous begins

…or is it the Mississippian?

The next period of the Paleozoic Era is called the Carboniferous, which means carbon-bearing in reference to the coal beds in the upper part of the system in many parts of the world. The name was invented by British geologists William Conybeare and William Phillips in 1822, making it the first to be established of the names we use today for the geologic periods.  

Now we have a nomenclature problem to deal with. In the book I put together in 1994, the month of June corresponds with the Mississippian Period. In the United States, the Carboniferous of Europe is divided into two distinct time spans, the Mississippian and the Pennsylvanian. Technically, in terms of international geologic names, the Mississippian and Pennsylvanian are sub-periods of the Carboniferous, but in part because of long-standing usage, in the United States the two are treated as full-fledged periods of geologic time.

In the U.S., the period takes its names from rocks of this age exposed along the Mississippi River, especially in western Illinois where these rocks are hundreds of feet thick.

For purposes of the original book and for these podcasts, I’m using U.S. nomenclature, so the month of June is the Mississippian and July will be the Pennsylvanian. But technically, they are parts of the Carboniferous Period. Sometimes you’ll see the Mississippian equated with early Carboniferous and the Pennsylvanian with the late Carboniferous. It’s all a matter of human convenience, and in this case, a matter of some notable differences between the rocks of this time period in the U.S. versus those of Europe.
—Richard I. Gibson

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