Jackson Volcano is an

extinct volcano A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates a ...

beneath the city of

Jackson, Mississippi Jackson, officially the City of Jackson, is the capital of and the most populous city in the U.S. state of Mississippi. The city is also one of two county seats of Hinds County, along with Raymond. The city had a population of 153,701 at t ...

, under the Mississippi Coliseum. The uplifted terrain around the volcano forms the Jackson Dome, an area of dense rock clearly noticeable in local gravity measurements. E.W. Hilgard published his theory of an

anticline In structural geology, an anticline is a type of fold that is an arch-like shape and has its oldest beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex up in which the hinge or crest is the ...

beneath Jackson in 1860 due to his observations of surface strata. The dome contains relatively pure carbon dioxide which is used in oil production in Gulf Coast oil fields. The

noble gas The noble gases (historically also the inert gases; sometimes referred to as aerogens) make up a class of chemical elements with similar properties; under standard conditions, they are all odorless, colorless, monatomic gases with very low ch ...

data suggests mantle origins with a date of 70 million years for the Jackson Dome intrusion. Geologists have evidence of repeated uplifts accompanied by dike intrusions and volcanic extrusions, erosion, and sedimentation with one coral reef having developed during a submergence. Much of the oil at the crest of the dome volatilized during a late uplift, but oil production wells numbered over a hundred in 1934. Jackson gas wells map

Jackson Volcano is believed to have been extinct for at least 66 million years. A hypothesis states that the Jackson Volcano and related igneous activity in Mississippi were a result of the North America Plate's passage over the Bermuda hotspot 66 million years ago. Alternatively, the volcanism may have been part of a worldwide eruption driven by superplumes, similar to the conditions that created the Deccan Traps and the

Siberian Traps The Siberian Traps (russian: Сибирские траппы, Sibirskiye trappy) is a large region of volcanic rock, known as a large igneous province, in Siberia, Russia. The massive eruptive event that formed the traps is one of the largest ...

. The volcano is one of four inside cities in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

, Diamond Head in

Honolulu Honolulu (; ) is the capital and largest city of the U.S. state of Hawaii, which is in the Pacific Ocean. It is an unincorporated county seat of the consolidated City and County of Honolulu, situated along the southeast coast of the island ...

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only state ...

, Pilot Butte in Bend,

Oregon Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho. T ...

, and

Mount Tabor Mount Tabor ( he, הר תבור) (Har Tavor) is located in Lower Galilee, Israel, at the eastern end of the Jezreel Valley, west of the Sea of Galilee. In the Hebrew Bible (Joshua, Judges), Mount Tabor is the site of the Battle of Mount Tabo ...

Portland Portland most commonly refers to: * Portland, Oregon, the largest city in the state of Oregon, in the Pacific Northwest region of the United States * Portland, Maine, the largest city in the state of Maine, in the New England region of the northeas ...

being the others. The volcano was discovered in 1819.

Geology

During the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...

, the

Western Interior Seaway The Western Interior Seaway (also called the Cretaceous Seaway, the Niobraran Sea, the North American Inland Sea, and the Western Interior Sea) was a large inland sea that split the continent of North America into two landmasses. The ancient sea ...

extended into present-day Mississippi forming the

Mississippi embayment The Mississippi embayment is a physiographic feature in the south-central United States, part of the Mississippi Alluvial Plain. It is essentially a northward continuation of the fluvial sediments of the Mississippi River Delta to its conflue ...

and depositing the Tuscaloosa Formation. Igneous activity progressed along an arc in the northern Gulf of Mexico Basin starting with the Prairie Creek

lamproite Lamproite is an ultrapotassic mantle-derived volcanic or subvolcanic rock. It has low CaO, Al2O3, Na2O, high K2O/Al2O3, a relatively high MgO content and extreme enrichment in incompatible elements. Lamproites are geographically widespread ...

(110 Ma) in the west to the Magnet Cove (105 Ma), Granite Mountain (90 Ma), Monroe-Sharkey Uplift with its Midnight Volcano (80 Ma), and finally the Jackson Dome (70 Ma) in the east. The Jackson intrusion

metamorphosed Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causi ...

the Cotton Valley formation and deformed it into a dome structure. Thus, the Tuscaloosa consists of ash and tuff at the dome and eroded igneous rock away from the dome. Volcanic material is also found in the overlying

Eutaw Formation The Eutaw Formation is a geological formation in North America, within the U.S. states of Alabama, Georgia, and Mississippi. The strata date from the late Coniacian to the early Santonian stage of the Late Cretaceous. It consists of the upper T ...

. Subsidence and sea level rise resulted in the deposition of the chalk and limestone of the

Selma Group The Selma Group is a geological formation in North America, within the U.S. states of Alabama, Mississippi, and Tennessee. The strata date from the Santonian to the Maastrichtian stages of the Late Cretaceous. The group is composed of, in ascend ...

. Natural gas accumulated in the Selma "gas rock" limestone underlying the Clayton limestone. The structure was noticed by Hopkins in 1917 and a successful gas well was drilled in 1930, but the field was nearly exhausted by 1939. Jackson Volcano ash within the Eutaw Formation produces oil in the Tinsley Oil Field, where oil was first discovered in the Woodruff Sandstone (Selma Chalk), an eroded sand from Jackson.

References

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External links

Jackson's Hidden Volcano
Volcanoes of Mississippi Extinct volcanoes of the United States Cretaceous volcanoes Landforms of Hinds County, Mississippi Hotspot volcanoes Subterranea of the United States