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December 4, 2020
Lidar hillshade imagery hints at the location of a future coal spoil landslide
A coal spoil landslide in southeastern Wise County, Virginia, appears traceable to a faint scarp visible in the spoil pile in a 2017 lidar dataset. The slide pre-dates October 2019 Google Earth imagery and post-dates the 2017 lidar data acquisition.
October 15, 2020
Normal fault, reverse fault, or both?
The new model, whose color scheme is admittedly quite shocking (think Pepto-Bismol bottle), is shown… The interesting fault is at the center of the image. The fault is traced in black in the lower image, with arrows indicating movement sense.
October 5, 2020
Interesting “sideways” movement of a large sandstone blockslide
A large sandstone blockslide in Highland County, Virginia presents an unusual appearance in LiDAR hillshade imagery–it appears to have moved sideways across a slope instead of directly down the slope.
September 14, 2020
The interesting geologic setting of Thomas Cole’s “The Oxbow”
New from The Geo Models blog: “Earlier this year, I became aware of the longer, geographically-specific title and learned that the painting does portray a real location with a particularly interesting geologic context…. Cole’s vantage point on Mt. Holyoke is east-northeast.
July 28, 2020
Fault-propagation folds in a sandbox model
New from The Geo Models: “These anticlines are recognizable as fault-propagation folds because the fault that offsets the deepest blue layer does not cut upward through the entire section. Displacement along the fault at depth is accommodated by folding of the overlying, un-faulted layers.”
July 17, 2020
Anticlines and synclines in exhumed model rift basins
Several Mesozoic rift basins have been exhumed along the Atlantic margin of North America, creating interesting patterns in sedimentary rock layers and igneous intrusions that originated during the breakup of Pangaea.
June 19, 2020
Fold-thrust belt outcrop pattern with doubly-plunging anticline
The latest post from The Geo Models blog.
May 22, 2020
Slump landslide models, with some rock or debris avalanche characteristics
New from The Geo Models blog: “The model landslides in this post were produced at the same time as the Llusco landslide model I wrote about last year. They were created using a similar setup, but the slide masses behaved very differently during movement.”
April 7, 2020
Interesting reverse faults in a simple extensional sandbox model
The different mechanical properties of the layers are apparent in the dip angles of the normal faults in the model. The master fault on the left side of the model (black line) is less steep in the weak microbeads, an expression of how their failure behavior differs from the stronger layers above and below.
March 20, 2020
Cracked mountaintops of the Virginia Valley and Ridge
A newly-released LiDAR data set reveals impressive ridge-top cracks associated with large rock slides in the Virginia Valley and Ridge. While the cracks are easily visible with LiDAR hillshade imagery, they appear to be covered by normal forest vegetation and would probably look like elongated depressions in the forest.
