Suggested Citation
Sherwood, W. C., 1964, Structure of the Jacksonburg Formation in Northampton and Lehigh Counties, Pennsylvania: Pennsylvania Geological Survey, 4th ser., General Geology Report 45, 64 p. [Available online.]
Description
This report describes the origin and development of structures in the Ordovician Jacksonburg Formation in the Great Valley section of what is now called the Ridge and Valley province in eastern Pennsylvania. The Jacksonburg is composed of limestones and shaly limestones and has a maximum thickness of 1,150 feet. The dominant structures include two stages of folding—early large-scale recumbent, isoclinal folds followed by later large-scale open folds. Faults include high- and low-angle thrust faults, cross faults, and lesser normal faults. Cleavage, joints, and lineations are also discussed. The report includes a 1:62,500-scale geologic map and cross sections.