Stratigraphy, genesis, and economic potential of the southern part of the Florida land-pebble phosphate field

The important and highly productive Florida land-pebble phosphate field is located in west central peninsular Florida in portions of Hillsborough, Polk, Hardee, and Manatee counties. The Pine Level phosphate area, described in detail in this report, is south of the previously known and mined deposits and occurs in portions of Manatee, Sarasota, and De Soto counties. Results of the current geologic study of the Pine Level phosphate deposit and the evaluation of the overall potential of this southern part of the land-pebble field are presented. The entire southern part of the phosphate field is underlain by more than 15,000 feet of Cretaceous and Tertiary carbonate strata. Phosphate deposits are confined to a thin clastic veneer of sediments that overlie the carbonate strata, and include the upper clastic member of the Hawthorn Formation of Miocene age, the Bone Valley Formation of Pliocene age, and unnamed strata of Pleistocene age. The total thickness of the phosphatic veneer is somewhat more than 100 feet. The Pine Level phosphate deposit, characteristic of the heretofore undescribed phosphate deposits in the southern part of the Florida land-pebble phosphate field, is compared with the deposits of the main producing area in the northern part of the field. The Pine Level deposit differs markedly from the deposits in the main producing district. The differences include the more localized and erratic distribution of mineable phosphate concentrations, inclusion of portions of the upper clastic member of the Hawthorn Formation within the mineable unit, origin and age or the deposits, significant contrasts in pebble and concentrate quality and quantity related to the mode of origin, the lack of development of the aluminum phosphate zone, and the enrichment of the contained carbonate fluorapatite by replacement processes. Very gentle scarps, representing Pleistocene sea standstills, divide the land-pebble field into several physiographic subdivisions. The physiographic provinces of the land-pebble field and the origin of the Pine Level deposit are related to three, and possibly four, Pleistocene interglacial marine advances that have reworked and recycled the apatite particles of the Bone Valley and Hawthorn Formations into new lower-level Pleistocene deposits that surround and flank buried remnant paleo-islands of the Bone Valley Formation. Field relations, chemical analyses and petrographic studies of a series of apatite pebbles ranging from deeply buried, low-grade, black, impure apatite to shallow, high-grade, relatively pure, white apatite, indicates that high-grade white apatite in the Pine Level deposit is derived from initial low-grade black apatite. The alteration occurs by progressive replacement of mineral impurities within the black apatite as erosion continually reduces the depth of burial and the black apatite is subjected to increasingly acidic and oxidizing ground water activity. Simplified evaluation criteria that serve to identify economically valuable deposits of the Pine Level phosphate type are described. These criteria are easily and readily determinable by the exploration geologist or engineer in search or such deposits. The slimes (clay) content of the Pine Level phosphate deposit is much lower than in the deposits of the main producing area and provides the basis for a new method of land reclamation that may eliminate the expensive and difficult conventional method or slimes disposal in permanent storage reservoirs --Abstract, pages ii-iii

Spatial Distribution Of Debitage At A Chert Procurement Site And A Cultural History Assessment On Orange Lake In North Central Florida

This project evaluated a 90 acre parcel of property located on the southern shore of Orange Lake in NCFL (North Central Florida). A cultural resource management style survey was conducted to determine what archeological evidence for prehistoric activity was present. In addition to this general assessment, this research was conducted in order to identify specific settlement patterns in the area and determine if they corresponded with the settlement strategies already identified for wetland environments within the area of north central Florida. Further, after a tool stone procurement zone was identified a study examining debitage size grade drop-off trends was conducted in an effort to separate quarrying and non-quarrying activity areas. The field work was conducted by excavating shovel test units 50 by 50 centimeters square and one meter deep. These were completed with a two person crew utilizing a shovel and quarter inch screen. Observations during each shovel test were recorded, artifacts bagged, and the unit location was recorded using a GPS unit. In the lab, artifacts were sorted based on sets of characteristics for each artifact type. Particular interest was awarded to debitage by sorting it into one of four screen size categories. Further separation was based on chert type and thermal alteration. These data were evaluated in terms of a distance drop-off model using correlation to explore proximity to local chert sources. The results of these tests proved there was not a sole quarry location in the northwest corner of the property as originally speculated but instead that raw tool stone had once outcropped along the entire length of the shore line. The drop-off tests reinforced the knowledge that chipped stone refuse generated at a quarrying site is unique to this site type. This means that the proportion of debitage size grades and frequency of thermally altered material changes in a predictable manner the further a shovel test is from the original stone source, as do the types of stone tools. In conclusion, raw tool stone acquisition and the manufacturing of tools from this source was of great importance for the prehistoric people of the area. The discovery of solid evidence for habitation beginning in the Early Archaic and growing in intensity forward into the Mississippian also shoOrange Lake was exploited throughout prehistory for the access to tool quality chert as well as fresh water and the ecotone environment of hardwood hammocks and prominent wetlands

United States Geological Survey Report TEI-524

The following documents are three maps on the stratigraphy between Hernando and Polk Counties, Florida. These maps are in relation to document USGS Bulletin 1074, "Stratigraphy of the Area Between Hernando and Hardee Counties, Florida"

Chicora research contribution 186

This study represents an intensive archaeological survey of two areas of Fort Stewart, Georgia known as the JAECK Drop Zone and the Taylors Creek area. The primary purpose of this investigation is to identify and assess the archaeological remains present at Fort Stewart for the National Register of Historic Places

2007 - 2008 University Catalog

Volume 97, Number 1, July 30, 2007 Published once a year, July 30, 2007https://scholarsrepository.llu.edu/univcatalog/1008/thumbnail.jp

2008 - 2009 University Catalog

Volume 98, Number 1, July 30, 2008 Published once a year, July 30, 2008https://scholarsrepository.llu.edu/univcatalog/1007/thumbnail.jp