Here is a panoramic photograph I took during a hike on Mohonk Mountain with some friends last weekend. The mountain range in the distance is a section of the Catskills. The middle ground is the Roundout Creek Valley. This valley is formed as a result of glacial retreat at the end of the most recent ice-age. It is located between the Shawangunk and Catskill Mountain Ranges of NY.
"As the climate warmed and ice thinned, the landscape was deglaciated – lobes of the continental ice sheet melted back from the central Catskills in periodic stages (Dineen, 1986). As the ice sheet pulled back (and occasionally re-advanced as distinct “lobes” of flowing ice) alpine glaciers formed on some of the newly exposed peaks (e.g. Hunter and Panther Mountains). Meltwater from the decaying ice left a complex array of stream (outwash plain) and ice-contact (kame) sand and gravel deposits. Pro-glacial lakes (large and small) formed where mountains, recessional moraines (deposits at former glacial margins) and ice impounded water and filled valley floors with thick deposits of layered silt and clay. Locally, “fossil” deltas from meltwater streams pouring into these meltwater impoundments are further evidence for the complex deglaciation of the region (Rich, 1935). As climate fluctuated during the period of deglaciation, temporary re- advances of ice from ice sheet lobes or alpine glaciers would leave till and other meltwater deposits on top of the earlier glacial material, resulting in the complex lateral and vertical distribution of glacial deposits observed today. After the ice fully retreated north, rainfall-runoff returned as the predominant sculptor of the landscape." -http://www.catskillstreams.org/pdfs/RCSMP/7_geology.pdf
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