Dating topography of the sierra nevada
Variations in topography through time have profound implications for processes as obvious as erosion and sedimentation and as diverse as global climate and the formation of mineral deposits.The interplay between topography and tectonics is exemplified by the evolution of topography of the Sierra Nevada and Great Basin (United States), and by geologists' interpretation of that evolution.
To what extent did the topography of these regions develop and evolve together or separately? (2004), uplift of the Sierra Nevada has consequences for adjacent regions, so events in the adjacent regions ought to reflect this uplift.Analysis of stable isotopes in material that incorporated ancient meteoric water is an important tool for determining paleoelevation.In the western United States, the underlying premise is that precipitation depletes O and D from air moving eastward off the Pacific Ocean and rising over the Sierra Nevada.They were able to sample from the former Pacific shoreline at the western edge of the Sierra Nevada eastward into the western Basin and Range (Fig. In addition to sampling a much longer transect that crosses a major tectonic boundary, they sampled zero-elevation deposits that provide a baseline for comparison with higher-elevation data. concluded that the modern crest of the Sierra Nevada near Lake Tahoe was ~2800 m high in the Oligocene, even greater than it is today.They also concluded that the region up to 50 km to the east, in the modern Basin and Range, was at about the same elevation; i.e., rivers were steep across the Sierra Nevada but flattened eastward across the Great Basin toward their headwaters.
Search for dating topography of the sierra nevada:
Continuity of paleodrainages from central Nevada across the Sierra Nevada to the Pacific Ocean demonstrates that the Sierra Nevada was the flank of the Nevadaplano, but does not resolve the absolute elevation of either.