 The Nemaha Range lies roughly 50 miles ( 80 km ) east of the Midcontinent rift , which forms a layer of basaltic rock around 1 @.@ 1 billion years old . This rift extends northward to Lake Superior and the surrounding area and southward to Kansas , then stops abruptly . Also present in the state is the Central Kansas Uplift , the faults of which produced several small earthquakes during the late 1980s . According to United States Geological Survey geophysicist Don Steeples , earthquakes at the Humboldt Zone have decreased and activity at the Uplift has increased . 
