By: magic-gigapans
Image: Callan Bentley, Mid-Atlantic Geo-Image Collection
License: Creative Commons Non Commercial ⧉

Uploaded: 29 Apr 2020
Last Updated: 20 May 2020

3.49 gigapixels
99,808 x 34,968 pixels
332.7 in X 116.6 in at 300dpi
23 pixels per inch

Crossing the southern Bighorn Range in Wyoming on Highway 16, there is a nice outcrop that illustrates (in part) the geologic history of Wyoming. Perspective of the gigapan is looking from south to north. The outcrop is on the eastern side of the Bighorn Laramide Uplift. From left (west) to right (east), we see the Gros Ventre Formation green shales and sandstones, the Gallatin Limestone, the Harding Sandstone (white), the Bighorn Dolostone ("Bighorn Dolomite"), a valley etched into the Darby Formation, and the Madison Limestone. The Gros Ventre and Gallatin are Cambrian. The Harding and Bighorn are Ordovician. The Darby is Devonian. The Madison is Mississippian. All of them are tilted (younging to the east) due to the overall antiformal structure of the Bighorn Range: it's a Laramide uplift bounded by the Powder River Basin on the east and the Bighorn Basin (both Laramide basins) on the west. Search the image for the charmismatic green flat-pebble conglomerate of the Gros Ventre Formation and Gallatin Formation, trace fossils, and a bucket of industrial-grade lubricant that someone dumped on the roadway. Hand samples of the flat pebble conglomerate can be explored here: https://viewer.gigamacro.com/view/dGmOemyAt8L6grsK https://viewer.gigamacro.com/view/3tE8Bwv4U4naCVDy