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Determination of Type and Distribution of Boron Minerals Associated With the Subsurface Evaporite Formations of East-Central Mississippi.
For Reference Only At Bureau Libraries :29 pages
Boracite (mg3b7o13cl) and other boron-bearing minerals were reported in the Gulf Coast Salt Basin in Clarke County, southwestern Alabama, and in smith County, south-central Mississippi. A detailed study of all available cuttings and cores taken from oil wells drilled into the Louann salt in Wayne County, MS, was made to determine the types of boron-bearing minerals present, their crystal habits and x-ray diffraction characteristics, and to establish their frequency of occurrence. Samples from about half of the 72 wells drilled to date in Wayne County to the Louann Salt Formation (most at depths of 12,000 to 15,000 ft) were located and studied. Cuttings from only nine wells showed boron-bearing minerals. Boracite was the only mineral retrieved successfully. It occurs as small euhedral crystals that are clear, pale yellow, or pale bluish-green. The cubic habit is most common, although tetrahedrons and combinations of both forms are also present. The only other boron mineral found was a small piece of hilgardite (ca2b5o9cl.H2o), which appears as a white aggregate. Wayne County has many wells in an area of >450 square miles. The locations of the nine wells yielding boracite from their cuttings are evenly distributed throughout the county. The apparently consistent occurrence of boron-bearing minerals in the study area suggests that their presence may be pervasive at the top of the Louann Salt throughout the entire salt basin.
CP; Final Contract Report;
For Reference Only At Bureau Libraries
University of Southern Miss
Page last reviewed: April 12, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division