Rock City  A Geological Wonder
                                                                                       Near Minneapolis, Kansas



The rocks at Rock City are huge sandstone concretions.  In an area about the size of
two football fields, 200 rocks - some as large as houses, dot the landscape.  There is
no other place in the World where there are so many concretions of such giant size.



Rock City is located 20 miles north of the I-70 and I-135 intersection,
3.6 miles southwest of Minneapolis, Ks.  Watch for the Rock City
signs.

Scientific explanation:  Although concretions occur where there is sedimentary rock, the Rock City
concretions are remarkable because of their great size and large number.  For years there was a
debate about the origin of the Rock City rocks.  Geologists are now in general agreement that they
were formed millions of years ago in Dakota Sandstone, which had been deposited when areas of
Kansas were covered by an inland sea.  After the sea water receded, the bottom of the sea became
the land surface.Ground waters containing dissolved calcium carbonate seeped through the porous
sandstone, cementing the sand grains together.  The spherical concretions slowly increased in size as
additional layers of sand were cemented.  Eventually the softer, surrounding sandstone was
eroded by wind, rain and floods, lowering the land surface.  This left many of the cement-hard
concretions totally exposed, while others are still partially embedded with only their rounded
tops showing.



For more photos of the Kansas landscape and rock formations,
visit Carol Yoho's Trip to North Western & West Central Kansas,
featuring Nicodemus, Jennings, Monument Rocks and Castle Rock.

All photos © 2002 by don Palmer