Lebanon County is a county located in the U.S. state of Pennsylvania. As of the 2010 census, the population was 133,568. Its county seat is Lebanon. The county was formed from portions of Dauphin and Lancaster counties in 1813, with minor boundary revisions in 1814 and 1821. Lebanon County comprises the Lebanon, PA Metropolitan Statistical Area, which is also included in the Harrisburg-York-Lebanon, PA Combined Statistical Area.
sedimentary rocks change with heat and pressure and become metamorphic rock then rocks melt into magma.
The mineral grains become realigned. They flatten out and get longer. Sedimentary rocks exposed to this kind of heat and pressure are transformed into new kinds of rocks. Limestone changes to marble. Shale changes to slate. Back to The Rock Cycle. Click here for more on Metamorphic Rock Formation from sedimentary rocks is caused by heat and pressure. Where does this heat and pressure come from? The heat and pressure comes from inside the earth. From the upper mantle up to within a few kilometers of the surface of the earth there is a tremendous amount of heat and pressure.