Classic Clastics

15 Points Per Correct Answer - No time limit  

1. You can sometimes tell the source rock of a particular sandstone by looking at the mineral composition of the grains. True False

2. What happens to clastic sedimentary rocks during diagenesis (the process by which freshly deposited sand or mud becomes rock)? Dissolution Compaction All of these Cementation

3. Your geology professor falls into a pool of quicksand. What should you advise him to do? (Keep in mind that if you help him out, he will give you a good grade in the class!) Thrash around wildly Be still Tread water, uh, quicksand Panic

4. I love loess. The word, that is. What exactly is loess? Fine, wind-blown dust An intermittent stream channel A hill shaped by the wind Seasonal light and dark layers

5. Occasionally, on the deep ocean floor, out in the middle of nowhere, one can find clastic sediments, ranging in size from fine sand to boulders and pebbles. Where does this come from, when there is nary a continent in sight? Passing ships Icebergs Aliens Subduction

6. Very coarse sediment, stream channel deposits, sheet flow deposits, debris-flow deposits, generally coarsening upwards-- what depositional environment? Delta Braided stream Alluvial fan Meandering stream

7. Dune-scale crossbedding interbedded with interdune areas, like deflationary pavements and playas. Ventifacts, mudcracks, raindrop imprints, and crystals of evaporites can sometimes also be found. What depositional environment? Meandering stream Alluvial fan Desert Beach

8. Which side of a meandering stream should you buy land on if you want to increase your real estate investment: the point bar side, or the cut bank side? Answer: (Either "point bar" or "cut bank.")

9. You want to see whether a particular sandstone came from a tidal flat. What sort of bedforms would you be looking for? Large-scale dunes (single current direction) Misplaced beach umbrellas Deep erosional scour features (single current direction) Herringbone cross-strata (reversing current directions)

10. Why should you care about clastics? All of these Sand = beaches! Thar be OIL! Soil to grow crops in!