If gabbro cuts across both sandstone and schist and schist is the oldest, draw a geological cross section showing relations between the rocks.
Write about the geological history of the region starting with the oldest events.© BrainMass Inc. brainmass.com October 9, 2019, 7:47 pm ad1c9bdddf
I'll leave the drawing up to you as it is pretty simple (two layers with another cutting across) - although be sure to account for the metamorphic rind that will occur from the gabbro's contact
As schist ...
The answer gives factors to consider when constructing a geologic history based on a simple cross sectional assemblage of rocks