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The Arkansas Paleozoic Stratigraphy Database is live!

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A new project I've been working on is now on the blog: the Arkansas Paleozoic Stratigraphy Database . This is a searchable database of the Paleozoic lithostratigraphic nomenclature in Arkansas with some related information. Within this database, you can search for stratigraphic names that not only are currently in use, but names that are now abandoned and replaced, as well as some that have recently been proposed. For each name you can find its age, any sub-divisions, proper usage as used by the USGS and AGS, historical usage (including past and present names), type locality or type area, type section location (if available), primary reference section location (if available), geographic distribution, etymology of the name, and citation of the original publication the name was used in. Also included for each name is a downloadable stratigraphic chart (PDF file) of either the Ozark or Ouachita/Arkansas River Valley region (whichever the unit is best exposed in) that illustrates the s...

Maps Below Our Feet

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About four years ago I ran across a website called Macrostrat.org , a website that started from the University of Wisconsin to compile stratigraphic data into a searchable database. While browsing their site, I saw the most beautiful geologic map. Don't get me wrong, there are great geologic maps that have been published, but this one struck a chord with me. Painted in the standard geologic colors, but with an earthy hue, was the surficial geology of the continental United States, northern Mexico, southern Canada, and the oceans. No borders between countries or states were visible, except for a couple of inexplicable odd lines along Michigan and Mexico that just happened to render. It's just geology. The zoom setting I had it on restricted the details to what are visble on a national scale. Not too generalized; not too specific. It looked as if it were a piece of abstract art with hints of Jackson Pollock evident in the Basin and Range province. I immediately thought tha...

Odd Stratigraphic Names

The USGS has a great website for searching stratigraphic names and I've found some names that are a little different. I've listed some of the most interesting ones below. Note that many of these are from the western states, and there's a reason for that. Names of lithostratigraphic units (groups, formations, members, and beds) must named after a geographic locality, such as a county, town, river, or mountain, per the nomenclatorial rules set forth in the North American Stratigraphic Code . Many of the geographic localities in the eastern US are more puritanical, if you will, from early European settlers, while the western states settled in the mid- to late-nineteenth century were named more loosely. Also, note that not all of these names are currently in use, some of these names may have been abandoned in favor of another name(s) and others may have been proposed, but not formally accepted for one reason or another (e.g. it must have sufficient reason for naming the unit,...