This weekend involved a trip out to Lake Ronkonkoma located on Long Island, NY. Long Island, NY owes most of its creation to that of glaciation dating back about 20-25k years ago. As the Wisconsin glaciation receded it left a great amount of gravel and loose rock sediment the Island started to take its current-day shape. There are four spines of this leftover sediment or glacial moraine that make up the island. The northern moraine which makes up the north shore and is also known as the Harbor Hill moraine. The southern moraine, known as the Ronkonkoma moraine is the main foundation of Long Island and runs directly through the middle of the island. The land south of this moraine down to the south shore is the called the outwash plain which is created with the outwash of the last glacier. Glaciers reverting north are largely responsible for the islands sandy southern shore created with glacial outwash and the islands rocky north shore due to large leftover sediment of gravel and glacial debris. Glaciers are also responsible for the creation of Lake Ronkonkoma a freshwater kettle lake in the middle of the island. The kettle lake was created from dead iceblocks leftover when glaciers retreated and when they melt to create a dimple appearance in the outwash plain.
LAKE RONKONKOMA
Moraine Spines of Long Island
Creation of Lake Ronkonkoma
Photo retrieved from http://dlib.info/home/esenig/formation.html
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