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 ar ...
beneath the city of
Jackson, Mississippi
Jackson, officially the City of Jackson, is the Capital city, capital of and the List of municipalities in Mississippi, most populous city in the U.S. state of Mississippi. The city is also one of two county seats of Hinds County, Mississippi, ...
, 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 che ...
data suggests mantle origins with a date of 70 million years for the Jackson Dome
intrusion
In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and com ...
. 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 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
The Deccan Traps is a large igneous province of west-central India (17–24°N, 73–74°E). It is one of the largest volcanic features on Earth, taking the form of a large shield volcano. It consists of numerous layers of solidified flood ...
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 large ...
.
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 U.S. state, states, a Washington, D.C., federal district, five ma ...
,
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 islan ...
,
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 ...
,
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 Idah ...
, 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 T ...
in
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 ...
,
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 Idah ...
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 se ...
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 conflu ...
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 up ...
. 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
{{reflist
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