South-Central IOA-IOCG province

Region Central, South Central
Mineral systems
Deposit types
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Focus area represents an extension of similar magnetic anomalies associated with known IOA-IOCG deposits in the Southeast Missouri Iron Metallogenic Province (aeromagnetic anomalies > 50 nT in a 1.4 Ga granite-rhyolite terrane and a depth to crystalline basement filter of <1 km).
Identified resources None outside of Missouri where there was historical production of iron.
Production Unknown.
Status Past mining only in Missouri for Fe.
Estimated resources Unknown.
Geologic maps Horton and others (2017), scale 1: 500,000.
Geophysical data Adequate Rank 1 aeromagnetic, gravity gradiometry, and aeroradiometric data over known deposits within the St. Francois Mountains (McCafferty, 2016a,b; McCafferty and others, 2016 ; McCafferty and Johnson, 2019); inadequate data surrounding the St. Francois Mountains and through the focus area permissive for IOA/IOCG mineralization.
Favorable rocks and structures 1.4 Ga felsic volcanic rocks, shallow intermediate intrusive rocks, and hypabyssal andesite-dacite intrusions.
Deposits Missouri: Pea Ridge (MRDS dep_id: 10090126; USMIN Site_ID: MO00012), Pilot Knob (MRDS dep_id: 10072191), Iron Mountain.
Evidence from mineral occurrences MRDS; USMIN.
Geochemical evidence None.
Geophysical evidence Unknown.
Evidence from other sources Previous work from other sources is cited in Slack and others (2016) and references therein.
Cover thickness and description Variably covered by younger rocks.
Authors Albert H. Hofstra, Anne E. McCafferty, Warren C. Day.
New data needs Geologic mapping, high resolution geophysics.
Geologic mapping and modeling needs 1:100,000 scale (estimated) map of the Precambrian surface composed of mafic to intermediate volcanic and intrusive rocks and felsic volcanic and plutonic rocks based on drill hole intercepts and geophysics.
Geophysical survey and modeling needs Aeromagnetic, gravity, magnetotelluric mapping of covered areas. Radiometric data useful for areas of exposed Precambrian rocks and mine waste piles.
Digital elevation data needs Variable lidar quality; some complete, some planned/funded, some inadequate.