Search results
Results from the WOW.Com Content Network
Pleistocene glaciers have also repeatedly visited the state over the last 100,000 years. These glaciers have left some evidence and carved out much of the landscape of the northern tier of the state. [2] A rock with high economic value from Pennsylvania is anthracite coal. Before mining began, there was an estimated 22.8 billion tons of ...
The ancestral Monongahela River, referred to as the Pittsburgh River, had flowed northwards from West Virginia, past Pittsburgh, into the Lake Erie basin and out the St. Lawrence River to the ocean. The lake began when the ice dammed the valley near Pittsburgh. [2] The lake changed sizes as the ice front moved and as the volume of water changed.
These low water gaps of the Allegheny are located in an arc in the depression between higher barrier ridge-lines, a family or succession of half-mountain passes letting out in a similar series of water courses, albeit rising more gradually from the west, where the depressed upland was caused by the weight of the immense plateau glacier that ...
Map of the Allegheny Plateau.The gray line differentiates the glaciated (northern) and unglaciated (southern) sections of the plateau. The unglaciated plateau extends southwestward into eastern Kentucky and Tennessee, where it is called the Cumberland Plateau.
The Allegheny Plateau (/ ˌ æ l ɪ ˈ ɡ eɪ n i / AL-ig-AY-nee) is a large dissected plateau area of the Appalachian Mountains in western and central New York, northern and western Pennsylvania, northern and western West Virginia, and eastern Ohio. It is divided into the unglaciated Allegheny Plateau and the glaciated Allegheny Plateau.
French Creek begins near French Creek, New York, and flows about 117 miles (188 km) to the Allegheny River at Franklin, Pennsylvania. The creek's drainage basin covers 1,270 square miles (3,300 km 2). [7] The watershed includes parts of Erie, Crawford, Venango, and Mercer counties in Pennsylvania as well as Chautauqua County in New York. [1]
Braddock Road connected Cumberland, Maryland (the upper limit of navigation on the Potomac River) and the forks of the Ohio River (the future Pittsburgh, Pennsylvania). It received its name from the British leader of the French and Indian War (1754–63), General Edward Braddock, who led the ill-fated Braddock expedition four years later. [22]
Lake Lacawac is a glacial lake that was formed more than 13,000 years ago (at the end of the last ice age). More specifically, it is known as a scour lake because when the Wisconsin glacier passed through the area, it formed a crater in the sandstone. [6] As the climate increased in warmth, the ice melted and resulted in Lake Lacawac.