| Ancestral Rockies |
Article Index for Ancestral |
Website Links For Rockies |
Information AboutAncestral Rockies |
|
The mountains eroded throughout the late Paleozoic and early Mesozoic , leaving a large deposition of debris in the surrounding Floodplain s that formed layers of Sedimentary Rock . By Jurassic time, the mountains had completely eroded away. The current Rocky Mountains were subsequently created by a second uplift, the Laramide Orogeny , that occurred in roughly the same location as the Ancestral Rockies and which began in Cretaceous time approximately 70 MYA. By the time of the second uplift that created the current range, the original mountains had long since eroded away. The current Rockies were forced upwards through the layers of Pennsylvanian and Permian sedimenatry remnants of the Ancetral Range. Such sedimentary remants were often tilted at steep angles along the flanks of the modern range and visible in many places throughout the Rockies, including prominently along the Dakota Hogback , a Pennsylvanian Sandstone formation that runs along the eastern flank of the modern Rockies. EXTERNAL LINK REFERENCES
|
|
|