Blanchard Springs Caverns is a

cave Caves or caverns are natural voids under the Earth's Planetary surface, surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend a relatively short distance undergrou ...

system located in the Ozark–St. Francis National Forest in Stone County in northern

Arkansas Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...

, USA, off Highway 14 a short distance north of Mountain View. It is the only tourist cave owned by the

United States Forest Service The United States Forest Service (USFS) is an agency within the United States Department of Agriculture, U.S. Department of Agriculture. It administers the nation's 154 United States National Forest, national forests and 20 United States Natio ...

and the only one owned by the federal government outside the

National Park System The National Park Service (NPS) is an agency of the United States federal government, within the US Department of the Interior. The service manages all national parks; most national monuments; and other natural, historical, and recreational ...

. Blanchard Springs Caverns is a three-level cave system, all of which can be viewed on guided tours. The Dripstone Trail runs through the uppermost level of caverns for about a and opened in 1973. The Discovery Trail opened in 1977 and loops through a section of the cavern, descending to the lower level of the cave, underground, as well as to the Natural Entrance, about below ground at that point, following the stream bed of the springs that created the cavern. This trail includes the Rimstone Dams, which create pools along the stream bed, and the Ghost Room, a small but very well decorated room in the uppermost level, with its huge white

flowstone Flowstones are sheetlike deposits of calcite or other carbonate minerals, formed where water flows down the walls or along the floors of a cave. They are typically found in "solution caves", in limestone, where they are the most common speleothe ...

. Also offered is a "Wild Cave" tour which allows access to undeveloped parts of the cave to more adventurous visitors. It follows the upstream section of the cave, allowing visitors to see all three levels as the original explorers did, continuing beyond where the Discovery Trail ends.

History

Residents knew about the cave by the 1930s and called it Half-Mile Cave. Systematic explorations began in the 1950s and continued sporadically in the 1960s. Explorers discovered a skeleton in the cave in 1955 which was incomplete; a cause of death could not be ascertained. The caverns were opened to the public in 1973 after 10 years of development on the Dripstone Trail.

Geology

With of surveyed passage, Blanchard is the second longest cave in Arkansas and the largest in volume. The limestone rock from which the caves and their formations developed was laid down in an ancient sea more than 350 million years ago. The cave is in middle

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...

to lower Mississippian rocks and extends through six stratigraphic formations. The cave has shown over five levels of passage development, but the upper two levels have eroded away as deepening valleys on the surface cut into them. The cave's formation was largely

phreatic ''Phreatic'' is a term used in hydrology to refer to aquifers, in speleology to refer to cave passages, and in volcanology to refer to a type of volcanic eruption. Hydrology The term phreatic (the word originates from the Greek , meaning "well" ...

in nature (formed below the water table) and passages have elliptical cross-sections typical of these formations. During the cave's development, active streams have been pirated from one level down to another without much

vadose The vadose zone (from the Latin word for "shallow"), also termed the unsaturated zone, is the part of Earth between the land surface and the top of the phreatic zone, the position at which the groundwater (the water in the soil's pores) is at ...

erosion occurring. The present stream currently rises from the cave at Blanchard Springs itself, at the same temperature as the cave, a constant, year-round . Most of the lower-level Discovery Route is in the approximately thick Plattin limestone whereas the Dripstone tour route in the uppermost level of the cave spans three units, the Boone Chert, Cason Shale and the Fernvale Limestone. Blanchard remains a "living" cave in part because of the care given by visitors and the United States Forest Service. Thus, the formations inside continue to grow as

calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...

is actively deposited by seeping and dripping water. One of the outstanding examples of formation growth is the Giant Flowstone, one of the largest in the U.S., at long, wide, and thick.

References

External links

Blanchard Springs Caverns website produced by the Stone County Tourist Guide

USDA Forest Service web page for Blanchard Springs Caverns
{{Authority control Caves of Arkansas Show caves in the United States Limestone caves Landforms of Stone County, Arkansas Protected areas of Stone County, Arkansas Ozark–St. Francis National Forest