For ONE of the mountain building episodes, describe the outcrop-scale evidence and the stratigraphic evidence that supports your interpretation. Also, please describe the relationship between mountain building and sea-level change. (You will need to consider additional outside research).
The transition between the Morrison and the Purgatoire formation was a mountain building event due to the fact that there was a drastic regional raise in sea level that corresponded to a dip in global sea level. This transition is a very evident unconformity due to the fact that between the end of the Jurassic and the beginning of the Cretaceous the sediment deposited has evidently seen drastically different depositional environments. This claim is supported …show more content…
Which mountain building event does this correspond to on your sea level curve?
Compression was a driving force as evidenced by the curvature in the cross-section of sediment. Such force could occur at convergent boundary, which could be where two continental crusts collide or the subduction of oceanic crust below continental crust. When two continental crusts collide compression forces crust to displace both up and down. In a subduction zone when an oceanic plate falls below a continental plate compression aides to create volcanoes on the continental crust. In both cases the compression could have forced the sediment to begin to fold as the cross section shows.
This corresponds to the mountain building event marked by the contact between the Morrison and the Purgatoire formation. This transition was denoted as a mountain building event due to the fact that there was a drastic regional raise in sea level that corresponded to a dip in the global sea level. Flag this …show more content…
This corresponds with a regression as the change in depositional environments marks a decrease in sea level over a short period of time. The transition from Hard Scrabble to Lower Fountain also represents a regression, but was likely caused by isostasy. Isostasy occurs when the elevation of Earth’s surface lowers in order to meet the level that the lithosphere naturally rests: this process would reduce the amount that the land was able to displace the regional sea level; therefore, decreasing the regional sea
The transition between the Morrison and the Purgatoire formation was a mountain building event due to the fact that there was a drastic regional raise in sea level that corresponded to a dip in global sea level. This transition is a very evident unconformity due to the fact that between the end of the Jurassic and the beginning of the Cretaceous the sediment deposited has evidently seen drastically different depositional environments. This claim is supported …show more content…
Which mountain building event does this correspond to on your sea level curve?
Compression was a driving force as evidenced by the curvature in the cross-section of sediment. Such force could occur at convergent boundary, which could be where two continental crusts collide or the subduction of oceanic crust below continental crust. When two continental crusts collide compression forces crust to displace both up and down. In a subduction zone when an oceanic plate falls below a continental plate compression aides to create volcanoes on the continental crust. In both cases the compression could have forced the sediment to begin to fold as the cross section shows.
This corresponds to the mountain building event marked by the contact between the Morrison and the Purgatoire formation. This transition was denoted as a mountain building event due to the fact that there was a drastic regional raise in sea level that corresponded to a dip in the global sea level. Flag this …show more content…
This corresponds with a regression as the change in depositional environments marks a decrease in sea level over a short period of time. The transition from Hard Scrabble to Lower Fountain also represents a regression, but was likely caused by isostasy. Isostasy occurs when the elevation of Earth’s surface lowers in order to meet the level that the lithosphere naturally rests: this process would reduce the amount that the land was able to displace the regional sea level; therefore, decreasing the regional sea