Time passed and the sea began to slowly recede to the west as land was pushed up. This uplift was due to movement occurring far beneath the Earth’s surface. Scientists have discovered that the Earth’s crust is composed of inter-connected sections, or plates. Death Valley lies near the boundary between two of these plates. As the plates slowly move in relation to each other, compressional forces gradually fold, warp and fracture the brittle crust. This widespread rock deformation and faulting occurred through most of the Mesozoic Era (251 - 65.5 million years ago.) While the Rocky Mountains and the Sierra Nevada formed, active mountain building alternated with times when erosion prevailed, working to breaking down the mountains that had formed.
[{"rock_types": "n/a", "era_formed": ["Mesozoic ", "Mesozoic Era"]}]
[{"rock_types": "n/a", "era_formed": "Mesozoic "}] [{"rock_types": "n/a", "era_formed": "Mesozoic Era"}] [{"rock_types": "n/a", "era_formed": "n/a"}]