 The mountains are characteristic of the Great Basin 's topography of mostly parallel mountain ranges alternating with flat valleys . <unk> generally north to south , the <unk> Creek Mountains consist primarily of fault blocks of basalt , which came from an ancient volcano and other <unk> , on top of older <unk> rocks . The southern end of the range , however , features many <unk> <unk> . As a whole , the faulted terrain is dominated by rolling hills and ridges cut by <unk> and canyons . 
