Tokio Cretaceous placers

Region Central, South Central
Mineral systems
Deposit types
Critical minerals
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Outline of the Tokio Formation, as ilmenite mainly occurs in the upper sandy part of the Cretaceous Tokio Formation. Placers are in the upper Tokio Formation.
Identified resources Identified resources and historical mining for titanium (ilmenite).
Production Minimal ilmenite recovered from surface mining.
Status Past mining; no current mining; drilling project by the Arkansas Geological Survey (Hanson, 1997).
Estimated resources Mineral Springs has 110,000 tons of TiO2 within 50 feet of the surface (heavy mineral sands).
Geologic maps Hanson and others (2005), scale 1:50,000; Davis and Fair (1959), scale 1:126,720; much of the area containing the Tokio Formation in Arkansas mapped at a scale of 1;24,000 by the Arkansas Geological Survey.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Unconsolidated Tokio Formation; ilmenite is found in weathered clays. Sediment of the Tokio Formation were deposited in a near-shore environment, so ilmenite concentrations may represent reworking of sands along ancient beaches (Holbrook, 1948).
Deposits Mineral Springs, Beulah Green-Pink Green placer (MRDS dep_id: 10068358).
Evidence from mineral occurrences Hanson (1997).
Geochemical evidence Four- to 8-foot intervals in a road cut in the Pink Green deposit contained 4.5% TiO2. Ilmenite in soil adjacent to the Beulah Green deposit gives it a 'salt-and-pepper' appearance (Holbrook, 1948).
Geophysical evidence None.
Evidence from other sources Augering and logs of water wells by U.S. Bureau of Mines confirms the concentrations of ilmenite in clays at depth (Holbrook, 1948).
Comments Ilmenite deposits are modestly radioactive due to the presence of monazite.
Cover thickness and description At the surface and at depths <100 feet.
Authors Corbin Cannon, W.D. Hanson.
New data needs High-resolution aeroradiometric coverage could identify deposits containing monazite.
Geologic mapping and modeling needs None requested at this time.
Geophysical survey and modeling needs High resolution aeromagnetic and aeroradiometric coverage needed.
Digital elevation data needs Lidar adequate.