Hi from Dillon, Montana

Field camp, 2019

It’s our last day in Dillon –we’ve been here for about the last ten days, mostly focused on mapping an area called Block Mountain. It’s got to be one of the most amazing places geologically I’ve seen! The basic structure of part of the area is a plunging anticline and syncline –formed as fault propagation folds above the large Hogback thrust that’s exposed to the south.
Here’s an aerial view!

Fault propagation folds in SW Montana looking northward down plunge. You can see a syncline just east of the anticline

But there’s so much more! And so many cool things to see! Below is just a sampling of the many interesting rocks and structures that I added to the site. You should be able to find all of them searching for the date: 1907 –as in July of 2019–or if you type in “SW Montana”.

Upright syncline in Triassic limestone of the Dinwoody Formation, SW Montana (190711-18)
Water gap, Montana –the Big Hole River is cutting through a high ridge of Pennsylvanian Quadrant Formation. (190707-45)
Geology students and right-lateral fault in limestone, Montana (190707-14)
Clast-supported pebble conglomerate of the Cretaceous Kootenai Formation, Montana. (190708-7)
Red-colored, coarse clastic beds, of the Cretaceous Kootenai Formation, Montana (190709-14)