What characterizes pre-, syn- and posttectonic sedimentary sequences in a halfgraben setting?
What will be an ideal response?
Answer: Pretectonic sedimentation in a half-graben is not related to the graben formation. It is expected to show no thickness change across the graben-bounding fault. Syntectonic sediments show thickening towards the graben-bounding fault and rotation so that the layers dip toward the footwall. Unconformities may exist in the high part of the rotated block, while evidence of continuous sedimentation is expected in the lower part (close to the fault). Posttectonic sediments fill in the relief created by the graben without any other evidence of fault movement than that related to differential compaction across the fault.
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A. increases as potential energy decreases. B. is maximum at the bottom of the pole. C. is equal to her potential energy when half way down. D. all of the above
Which of the following events would not be considered a migration pull factor?
A) opportunity to get an education B) living on a floodplain C) religious freedom D) a new industry that requires workers E) safety from violent crimes
The Southern Hemisphere is also referred to as the water hemisphere
Indicate whether the statement is true or false
Small streams with no tributaries are:
a. first order b. second order c. third order d. trunk streams