Geology of Post Rock Country

Geology of Post Rock Country. An inland sea forms today's rock outcroppings. , Post Rock Country is in the heart of the Smoky Hills, named for the early-morning fog that forms in its valleys. The region is defined by rock outcroppings, formed more than 66 million years ago during the Cretaceous Age when the ancient inland sea that covered much of Kansas was deeper and larger than in earlier eras. Two distinct types of outcroppings occur along the Byway: Greenhorn Limestone and Dakota Formation Sandstone., Greenhorn Limestone , Found in the center of the Smoky Hills, Greenhorn or post rock limestone was deposited in a shallower part of the cretaceous sea. Near the top of the Greenhorn layer is a bed called Fencepost limestone, often exposed by erosion. This foot-thick layer of limestone with a distinctive reddish band was especially important to early settlers. Because timber was scarce, they used this limestone in place of wood to build fenceposts, homes, churches, businesses, bridges, and sidewalks., Dakota Formation Sandstone , Dakota Formation Sandstone can be found in a belt from Rice County in the south to Washington County in the north. Sandstones are the remains of beach sands and sediments deposited by rivers draining into the early Cretaceous sea. These sandstones often cap the hills and buttes in this part of the Smoky Hills. The Pawnee Nation often created petroglyphs on the sandstone, some of which can be seen along the Post Rock Byway at Wilson Lake., Landscape , Here, the Smoky Hills support mixed prairie, marking a transition from the eastern tallgrass prairies to the western shortgrass prairie. Trees grew along river and stream valleys but were uncommon on the highland. The lack of tree cover, soil composition, and prevalence of limestone created a rugged geography that produced many small farming towns, each with a distinctive history and culture. Communities like Lucas, Wilson, and Sylvan Grove complement the natural landscape to make Post Rock Country unique.