| Elephant Rocks State Park | |
|---|---|
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  Location in Missouri Show map of Missouri Elephant Rocks State Park (the United States) Show map of the United States | |
| Location | Iron County, Missouri, United States |
| Coordinates | 37°39′16″N90°41′17″W / 37.65444°N 90.68806°W /37.65444; -90.68806 |
| Area | 133.75 acres (54.13 ha)[1] |
| Elevation | 1,273 ft (388 m) |
| Established | 1967[2] |
| Administered by | Missouri Department of Natural Resources |
| Visitors | 106,869 (in 2022)[3] |
| Website | Official website |
Elephant Rocks State Park is a geologic reserve and public recreation area encompassing an outcropping ofPrecambriangranite in theSaint Francois Mountains in theU.S. state ofMissouri. Thestate park is named for a string of large graniteboulders which resemble a train of pinkcircuselephants.[4] The park was created following the donation of the land to the state in 1967 by geologist Dr. John Stafford Brown.[5] The park is used for picnicking, rock climbing, and trail exploration. It is managed by theMissouri Department of Natural Resources.[4]
TheElephant Rocks, for which Elephant Rocks State Park is named, is a pile of residualboulders of weathered Graniteville Granite. It is a medium- to coarse-grained,muscovite-biotite alkali granite that, on the average, consists of 55 percent alkalifeldspar, 40 percentquartz, and less than 5 percent mafic minerals. The Graniteville Granite is apluton formed 1.4 billion years ago in theProterozoic by the cooling ofmagma that intruded into thevolcanicstrata andcountry rock associated with a collapsedcaldera.[6][7] Nearly verticalfractures formed in the stone as it cooled, and uplift of the granite enhanced the fracturing. Eventually the overlyingstrata were removed througherosion, exposing thegranite pluton. Before it was exposed, groundwaterweathered the granite along fracturejoints creatingcorestones of relatively solid altered granite embedded within friablesaprolite.Surface runoff later eroded the saprolite that once surrounded the corestones and left, what are now locally calledelephant rocks as boulders perched on the ground surface.[6]
The reddish or pink granite has been quarried in this area since 1869, and two abandoned granitequarries are within the park. These and others nearby have provided red architectural granite for buildings in states fromMassachusetts toCalifornia, but most particularly inSt. Louis, including stone for St. Louis City Hall and the piers of theEads 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 itswharf on theMississippi River. Stone quarried in the area currently is used formortuary monuments and is known commercially as Missouri Red monument stone.[6][8]
A one-mile (2 km) circular interpretive trail in the Elephant Rocks Natural Area, called the Braille Trail, is the first in Missouri state parks designed specifically for visitors with visual and physical challenges. Spur trails off the main trail include one passing through "Fat Man's Squeeze," a narrow gap between two boulders that leads hikers to an abandoned quarry, and another that goes through "The Maze," a 100-foot (30.48 meter) section of scattered boulders.[9] The park's picnicking area includesADA-compliant facilities.[10]
