Edited by James E. Palmer and Russell R. Dutcher - University of ...

were mostly 2 to 4 feet (.6 to 1.2 m) thick.No mines are currently operating in the area.Cannelton's main industry today is asewer-tile factory. Until 1957 this plant usedclay from the lower part of the MansfieldFormation taken from drift mines in the nearbyhills; clay now is brought across the riverfrom surface mines inEntry to toll bridge; continue ahead can Indi-and Locks. Completed in. Army Corps of Engineers,these structures control the flow of and facilitatenavigation on this part of the Ohio River,the most heavily travelled waterway in theworld. The locks are 11 feet (34 m) wide and608 and 1200 feet (1 3 and 366 m) long;they were designed to handle the largest practicabletows in one locking operation. Thisstructure with its 25-foot (7.6-m) lift replacesthree older structures upstream, and it is nowpossible for tows to travel from this lock 115river miles (185 km) upstream to Louisville,Kentucky, without passing through anotherBock.The locks are founded on limestone nearthe middle of the Buffalo Wallow Group (fig.IN-2); the dam is foun ed partly on bedrockand partly on outwask and and gravel of thevalley fill, because bedrock is deeper at the farend of the dam than at the near end. A measuredsection at this place (Gray, I9791 ispresented in figure IN-1 2.) on access road; ascend hillpast exposures of sandstones and shales of theMansfieid Formation.Rest stop. Turn left (east) and park in parkinglot; proceed ahead (south) on foot to theoverlook platform.Leave rest stop. Proceed west down steep hillpast exposures of sandstones and shales of theMansf ield Formation.Turn right (west) onto lndiana Route 66.Turn Deft (south) onto lndiana Route 237;approach to Lincoln TrailCross Ohio River and ehope you enjoyed lndianaFIELD TRIP 9IROAB LOG