EXAM REVIEW - LANDFORMS OF THE NYC REGION
1. A blank map of the NYC region is shown above.
- On the map, indicate with a dot pattern where, within the five boroughs of NYC, bedrock is either at the surface or just beneath the surface of the land.
- On the map, indicate with a series of parallel lines the area where a series of parallel ridges and valleys would be found.
- One investigator proposes the hypothesis that the parallel ridges and valleys are the result of a landslide. Make a prediction as to what you would find if you were to examine the region that would be a good test of the hypothesis.
I predict that I would find: loose sediment that would have poor layering and no sorting.
- If the area were examined, would the prediction be fulfilled?
In the space below, justify your answer in terms of the real geology of the region. Be as specific as possible.
There is bedrock at or close to the surface. (A more precise answer would be that bedrock composed of gneiss, schist and marble lies at or close to the surface, but the first, less precise answer is acceptable.)
- Another investigator agrees that the parallel ridges and valleys are the result of a landslide. As a test of the hypothesis, the investigator predicts that loose material will be found directly underneath the surface of the land. In the space below, explain why this prediction is not a strong test of the hypothesis.
While it is true that landslides would form deposits of loose material, so would streams, ice and other depositional agents. The prediction does not test the hypothesis strongly because it does not distinguish between the different depositional agents. If the prediction had been that poorly layered, unsorted sediment would be found, that would be a much stronger test. (Of course, the prediction would not have been fulfilled and the hypothesis would not have been supported.)
- Yet another investigator agrees that the parallel ridges and valleys are the result of a landslide. Asked to make a prediction that will test the hypothesis, the investigator states that landslides are often triggered by earthquakes. Is the investigator's statement a useful test of the hypothesis?
Explain your answer in the space below.
|It is not useful because it is merely another hypothesis, not a prediction of what might be observed if the first hypothesis were true. |
Note that to answer these questions correctly, you need to know
- The major landforms of the area.
- Where they are located.
- In general terms, what material directly underlies these landforms.
- Successful hypotheses as to what processes might have formed each landform.
- Useful tests of these hypotheses.
2. Refer to the table below.
|2. Lou, Lulu and their friend Drew are intrigued by a photo of a conical mountain rising from a flat plain.|
|Lou suggests that the hill is a volcano, and predicts that if they look at a contour map, they will see a depression at the top of the hill.|
Lulu suggests it a place where people have dumped the waste material from a nearby quarry. She predicts a map will show a depression caused by people digging for something valuable.
Drew suggests that the hill is all that remains of a once much more extensive high, flat area, much of which has been removed by erosion. She predicts that the map will show a nearby plateau that rises to the same elevation as the top of the hill.
|The actual map is shown to the right. |
Evaluate each of the three hypotheses as 'likely', 'unlikely', or uncertain due to 'no evidence'. Explain your evaluations.
- Lou's hypothesis seems to be 'unlikely' because there is no depression at the top of the hill. However, it is possible that the contour interval is too large for the depression to show - in which case the evaluation would be 'no evidence'.
- Lulu's hypothesis seems to be 'unlikely' because there is no depression near the hill. However, it is possible that the contour interval is too large for the depression to show - in which case the evaluation would be 'no evidence'.
- Drew's hypothesis seems to be 'unlikely' because there is no nearby plateau. However, it is possible that the plateau is just outside the area shown on the map - in which case the evaluation would be 'no evidence'.
3. In trying to solve a crime, detectives often claim that they use a 'scientific method'. Explain what they mean. Are they correct that their approach is 'scientific'? Review 'A Scientific Method'.
4. What depositional agents are likely to form well-sorted deposits? Review the 'Deposition' rollovers.
5. How may glacial meltwater deposits be distinguished from ordinary stream deposits? By their association with glacial landforms - such as an adjacent belt of irregular hills made of unsorted, unlayered sediment.
David J. Leveson