What makes a mountain range as tall as the Rockies or Alps disappear just as quickly as it was uplifted, when other mountains stick around for hundreds of millions of years? The Caledonides in the Scottish Highlands may be able to shed some light on this question.
Upper Left--Old Red Sandstone flagstones at Sarclet Head;
Upper Right--ORS conglomerates at Coldbackie;
Lower Left--Sheared clasts at Faraid Head;
Lower Right--Marker for the Moine Thrust near Assynt.
OROGENIC HEAT FLOW AND DEFORMATION
To help solve the collapse problem, we look closer to home as well. Can ancient heat conditions in rocks of the Appalachians tell us more about how mountain ranges move when they can no longer hold themselves up?
Top--trail to Cascade Falls, Virginia
Bottom--the Valley and Ridge Appalachian Province in Virginia
Nevada and Missouri
When topography weathers and erodes, it may leave a "timestamp" in the form of diagenetic or remagnetized iron-bearing minerals where surface processes played a role. I investigated this possibility with my MS advisor, Dr. Shannon Dulin, using paleo- and rock magnetism and petrography.
Top left--the Great Unconformity at Frenchman Mountain, Nevada;
Top right--Paleomagnetic sampling of Tapeats Sandstone, Nevada;
Lower left--the Grassy Mountain Unconformity in SE Missouri;
Lower right--Drilling paleomagnetic samples in Nevada