Elephant Rocks State Park

Elephant Rocks State Park in the U.S. state of Missouri encompasses an outcropping of Precambrian granite in the Saint Francois Mountains. It is named for a string of large granite boulders which resemble a train of pink circus elephants.

The park has thirty picnic sites and a one mile (2 km) circular interpretive trail in the Elephant Rocks Natural Area. This trail is called the Braille Trail and is unique among Missouri state parks in being designed specifically for visitors with visual and physical handicaps. There is no camping permitted at this park, but several other state parks in the vicinity have camping facilities.

Geologically, Elephant Rocks State Park consists of a tor, which is a high, isolated rocky peak, usually of jointed and weathered granite. The alkali granite here was formed in the Proterozoic 1500 million years ago from a dome of molten magma. Nearly vertical fractures formed in the stone as it cooled, and uplift of the formation enhanced the fracturing. Eventually the overlying strata was removed through erosion, exposing the granite dome. With exposure, water and ice worked to weather and erode the surface of the granite and to expand the fracture joints. Eons of weathering produced the rounded boulders that are the park's signature.

The reddish or pink granite has been quarried in this area since 1869, and two abandoned granite quarries are within the park. These and others nearby have provided red architectural granite for buildings in states from Massachusetts to California, but most particularly in St. Louis, including stone for the piers of the Eads Bridge. Stones unsuitable for architectural use were made into shoebox-sized paving stones that were used on the streets of St. Louis as well as on its wharf on the Mississippi river. Stone quarried in the area currently is used for mortuary monuments and is know commercially as Missouri Red monument stone.

External links

* [http://www.mostateparks.com/elephantrock.htm Elephant Rocks State Park official website]
* [http://www.pittstate.edu/services/scied/Teachers/Field/Camp/Elephant/elephant.htm Elephant Rocks State Park] page of Science Education at Pittsburgh State University [http://www.pittstate.edu/services/scied/index.html]