Question

drumlins as in moraines, the unsorted and unlayered nature of till supports the idea that they are deposited by ice.

1. what important information can be gained by studying drumlins?

how can we recognize deposition by meltwater?
at the end of a glacier there are usually large quantities of water. some flows from beneath the ice and more comes from the melting ice front. sediments deposited by water from melting ice are known as outwash. the principal difference between till and outwash is that outwash deposits, like other sediments laid down by water, are sorted and layered. kettles and kettle lakes are common in outwash plains where blocks of ice caught in the outwash later melt leaving depressions. the difference between ice deposits and meltwater deposits can be seen very clearly on long island. most of the island is made of sediments that can be traced back to glacial origin. the only bedrock on long island is in new york city at the far western end of the island. high hills of unsorted sediment in the harbor hill moraine dominate the north shore of long island. the beaches of the north shore are composed of pebbles, cobbles, and even large boulders washed out of the moraine. these moraines were pushed into place by moving ice. however, most beaches on the south shore are made of sand washed out of the glaciers by meltwater. a few kilometers inland from the southern beaches are deposits of sand that show layering and sorting: strong evidence that the southern part of long island is made of sediment deposited by water, not by ice.

Explanation:

The text mentions that the unsorted and unlayered nature of till (related to drumlins) supports the idea of ice - deposition. Studying drumlins can thus give information about past glacial activity.

Answer:

Information about past glacial activity.