It assumed its current form as the ice-sheets of the last glacial period melted away between 20,000 and 15,000 years ago leaving behind a thick cover of glacial till and extensive tracts of glacio-fluvial sand and gravel.
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request. ### Instruction: List the MITRE techniques contained in the text. ### Input: It assumed its current form as the ice-sheets of the last glacial period melted away between 20,000 and 15,000 years ago leaving behind a thick cover of glacial till and extensive tracts of glacio-fluvial sand and gravel. ### Response: .