At least four continental glaciers reached their greatest extent just north of Moraine State Park. These huge ice sheets, sometimes over a mile thick, transported stones and soil in, within, beneath and in front of them, reshaping the land.
When the glaciers retreated, they left behind the accumulated debris, which is called a moraine. Deposits of gravel, sand, and clay found throughout the area are evidence of the glaciers and their moraines.
During one or more of the ice advances, a continental glacier dammed area creeks making three glacial lakes. To the north, north flowing Slippery Rock Creek filled giant Lake Edmund. To the southeast, extinct McConnells Run filled tiny Lake Prouty. In the middle, north flowing Muddy Creek filled the medium-sized Lake Watts.
The glacier dammed Lake Prouty on the edge of the drainage divide. Eventually Lake Prouty spilled over and rushed to the south, initiating the erosion Slippery Rock Creek Gorge. Lakes Watts and Edmund drained into the gorge, eroding it deeper and making Slippery Rock Creek flow south. Areas of the 400-foot deep Slippery Rock Gorge may be seen at nearby McConnells Mill State Park.
The glacier created a landscape of rolling hills topped with hardwood trees and swamps in the valley bottoms.
Detailed information about the glacial geology of the area is available from:
Trail of Geology - Moraine and McConnells Mill State Parks Guide (PDF)
This driving tour brochure corresponds to numbered posts throughout the park and surrounding area.
American Indians found the land excellent for hunting grounds. In the 1800s, farmers cleared the forests and drained the swamps. Sand and gravel deposited by the glaciers were mined and sold. Limestone and clay were mined to make ceramics. Local shale was used to make bricks. The discovery of bituminous coal ushered in a boom time for the region. Seven coal beds were deep-mined and later the land was strip-mined.
During the late 1800s, wells were drilled to extract oil and gas. When the wells dried up, they were abandoned and left unsealed.
The Western Allegheny Railroad was built to transport these extracted minerals to Pittsburgh. The railroad ran the full length of the Muddy Creek Valley and through the Village of Isle, where the PA 528 bridge is today. Abandoned in 1939, the old railroad grade is still visible west of the dam and in the Muddy Creek finger of Lake Arthur.
Much of the park area lost its topsoil and many streams were polluted with abandoned mine drainage. The land remained largely unoccupied.
During 1926, Frank W. Preston of England moved to the town of Meridian and opened a glass research lab. A leader in glass research, Dr. Preston was also an amateur geologist and naturalist. On a trip to the Muddy Creek Valley, he noticed that the hills had a unique shape and attributed it to the glacial periods.
Preston studied the land for decades and named many of the landforms after Edmund Watts Arthur, a prominent Pittsburgh attorney and naturalist. With the support of friends, Preston formed the Western Pennsylvania Conservancy to purchase land to recreate the glacial landscape and preserve open space.
Muddy Creek was dammed to create modern Lake Arthur as a smaller version of glacial Lake Watts.
The former Pennsylvania departments of Forests and Waters and Mines and Mineral Industries helped to reclaim the abused land. Workers:
Sealed deep mines
Back-filled and graded strip mines
Plugged 422 gas and oil wells
Fertilized the soil
Planted thousands of trees, shrubs, grasses, and clovers
The dam was completed by November of 1968, and, during 1970, Lake Arthur reached its full level. Moraine State Park was dedicated on May 23, 1970.
Lake Arthur reminds us that our use of natural resources to meet human needs requires decisions that affect the quality of the environment.
Detailed information about the Muddy Creek Oil Field is available from the:
Trail of Geology Muddy Creek Oil Field Park Guide (PDF)
Historic Points of Interest
Construction began before the American Revolution on this cabin of hand-hewn logs and hand-carved stone. A fine example of pioneer construction, there is:
A safe built within a stone wall
An authentic wagon wheel chandelier
Walls made of wormy American chestnut
Located behind the Davis Hollow Marina, it was used as a summer home by Mrs. Katherine Davis and her sister Miss Eleanor Holt.
Central Power House
An operating central power is tucked in the woods just beyond Muskrat Cove where a stream crosses under the service road.
Built at the turn of the century, it contains a Bessemer engine, pumping jacks, and other equipment used during the early days of the oil industry. The engine is operated several times a year.
A book on the Muddy Creek Oil Field is for sale at the park office.