Pennsylvanian
noun · first attested 1891
North America cut the Carboniferous in half and named the halves after a state and a river.
The later subperiod of the Carboniferous, about 323 to 299 million years ago.
41.0000°N -77.5000°W · Q1400
Record
- Relationship
- Named from the place
- Confidence
- Well attestedThe place link is the standard scholarly account.
- Attested
- 1891
- Part of speech
- noun
Explanations here are written for this atlas. Dictionary text is not copied; the sources are linked so the claim can be checked.
- Step 1
Pennsylvania
- In English
Pennsylvanian
Henry Shaler Williams coined Pennsylvanian in 1891 for the upper Carboniferous strata that are well exposed in Pennsylvania and hold its coal. It pairs with the Mississippian below, named in 1870 for limestone along the upper Mississippi valley. The division began as a convenience for American geologists working with rocks that looked nothing like the European sequence, and the International Commission on Stratigraphy has since made the two formal global subperiods.