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Pennsylvania Landforms. Mrs. Shull. Pennsylvania Geography. What is geography? That sounds like geology. Geography is the study of the shape of the land. Does all of Pennsylvania have the same landforms? NO! There are lots of different geographic areas in Pennsylvania.
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Pennsylvania Landforms Mrs. Shull
Pennsylvania Geography • What is geography? That sounds like geology. • Geography is the study of the shape of the land. • Does all of Pennsylvania have the same landforms? • NO! • There are lots of different geographic areas in Pennsylvania.
What are the landforms where we live? • The Allegheny Plateau. • A plateau is a relatively level area that is raised up above the rest of the land. • Plateaus are often cut by steep-sided valleys called canyons. • “Mountains” and valleys – most mountains are about the same height. • Streams have a branching, tree-like – or dendritic- pattern. • Ridges and valleys – long, narrow ridges and broad valleys. • The Susquehanna River flows around the ridge.
Muncy Creek Gaging Station http://waterdata.usgs.gov/nwis/uv?01553005
How were these valleys formed? • Was this area once covered by water? • YES! A large body of water once covered the land here. • The rocks were formed from sediments being laid down, then compressed – or “pressed” together. • The land was “uplifted” – or raised, and the water drained away. • The land was eroded, or washed, away by stream water. • Freezing and thawing helped to “break up” the rock. • Did a glacier cover the land where we live? • NO. But, it came pretty close. Areas to the north of us, and in the Poconos in Pennsylvania were covered by glaciers.
How were these mountains formed? • The rock beds, which were formed the same way as the ones above, were then “squashed” or folded by colliding land masses. • Europe and Africa collided with North America. • After the land was uplifted and drained, streams started eroding away the weaker rocks, making big valleys.
What is "devil's turnip patch"? • Boulder field made from ice within the soil and rock, causing the rocks to “creep”. • From being located “near” glaciers, the climate was cold enough to freeze the water in the soil.
Are there any caves around here? • YES. There are some areas where you can find caves. • How did caves form? • The rock in which caves form is called limestone. It is easily dissolved away by water. • The water dissolves “pockets” of the limestone, leaving caves.
Pop Quiz! • What kind of rocks do we find around Muncy? • Igneous • Sedimentary • Metamorphic • How were the mountains around Muncy formed? • Was Muncy covered by a glacier? • What kind of weathering causes caves and sinkholes?