Champlain Valley southward into the Valley of Vermont. The Vermont Lowlands are primarily underlain by sedimentary rocks, especially limestone and shale, though metamorphic rocks such as marble and slate are also present. Lake Champlain is situated in the Champlain Valley between the Green Mountains of Vermont and the Adirondack Mountains of New York, drained northward by the Richelieu River into the St. Lawrence River at Sorel-Tracy, Quebec (northeast of Montreal). Major tributaries of Lake Champlain include Otter Creek and the Winooski, Missisquoi, and Lamoille rivers in Vermont, and the Ausable, Chazy, Boquet, and Saranac rivers in New York. Lake Champlain also receives
Geography of New York (state) the north. Additionally, New York touches the Atlantic Ocean to the southeast, and two of the Great Lakes: Lake Erie to the west and Lake Ontario to the northwest. New York is part of the Marcellus Shale, a gas-rich rock formation which also extends across Ohio, Pennsylvania and West Virginia. New York lies upon the portion of the Appalachian Mountains where the mountains generally assume the character of hills and finally sink to a level of the lowlands that surround the great depression filled by Lake Ontario and the St. Lawrence River. Three distinct mountain masses can be identified in