Imagine three layers of sedimentary rock that sit horizontally one on top of the
ID: 106192 • Letter: I
Question
Imagine three layers of sedimentary rock that sit horizontally one on top of the other, like a layer cake. As you investigate further, you find that a fault has cut and offset the two lowermost layers, but doesn’t cut and offset the top most layer. What scenario below is the most likely to have occurred in this situation? a. When the fault cut the layers, it didn’t cut all the way to the top. It stopped cutting and offsetting just below the top layer. b. The top layer didn’t exist when the fault offset the bottom layers. The top layer deposited after the fault cut and offset the bottom two layers. c. There is no way to tell what happened in this situation.
Explanation / Answer
A fault truncate all the previously deposited layer.
Therefore, if it cuts and offset two lowermost layers but doesn’t cut and offset the top most layer, the possible explanation will be;
b. The top layer didn’t exist when the fault offset the bottom layers. The top layer deposited after the fault cut and offset the bottom two layers.