Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Bone”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

Radium in ground water from public-water supplies in northern Illinois

Concentrations of the naturally occurring radioactive isotopes radium-226 and radium-228 in excess of the U.S. Environmental Protection Agency standard for drinking water of 5 picocuries per liter have been detected in water from deep aquifers used for public supply that underly parts of northern Illinois. Radium, a known carcinogen, has the potential to cause bone and sinus cancer if ingested in sufficient amounts. This Fact Sheet briefly describes the formation and decay of radium, the health risks associated with radium ingestion, procedures for testing radium concentrations in water, and the occurrence of radium in ground water used for public-water supplies in northern Illinois and provides information on technologies that can reduce the amount of radium in drinking water.

Fact Sheet↗

Map and interpretation of aeromagnetic data for the Wild Rogue Wilderness, Coos and Curry Counties, Oregon

The Wild Rogue Wilderness is located in Coos and Curry Counties, southwestern Oregon and covers part of the Bone Mountain, Marial, and Agness 15-minute quadrangles (fig. 1). It is an elongate area 19 mi by 1 to 3 mi (31 km by 1.3 to 5 km) and covers approximately 35,818 acres extending from the town of Agness to Mount Bolivar. The mapped geology of the Wild Rogue Wilderness (Gray and others, 1982) consists of a tectonic wedge of volcanic and intrusive rocks of Jurassic age surrounded on all sides by thick sequences of Jurassic, Creacetous, and Tertiary sedimentary rocks. Normally, volcanic and intrusive rocks are more magnetic than sedimentary rocks, a property which should be reflected by the areomagnetic data. We conclude, however, that most of the magnetic anomalies of the Wild Rogue Wilderness are caused by magnetic rocks that are not exposed but which occur at relatively shallow depth below the topographic surface.

Oregon↗

Geologic map of the Myrtle Point area, Coos County, Oregon

The mapped area lies in theo southern end of the Coos Bay coal field. Coal occurs onle in the upper and lower members of the Coaledo Formation. Nearly all the coal mined in the Coos Bay coal field was from the upper member of the Coaledo Formation. In the mapped area, most of this member has been eroded; only a few hundred feed of the basal strata remains. Allen and Baldwin (1944, p. 131, 116) reported 2 feet 7 inches of coal and bone along Hall creek in the NW1/4NW1/4 sec. 11, T. 29 S., R. 13 W., and 4 feet of coal and bony coal at the Albee prospect near the center of the NE1/4 sec. 4 T. 29 S., 13 W.

Oregon↗

Selected hydrologic data for the field demonstration of three permeable reactive barriers near Fry Canyon, Utah, 1996-2000

Three permeable reactive barriers (PRBs) were installed near Fry Canyon, Utah, in August 1997 to demonstrate the use of PRBs to control the migration of uranium in ground water. Reactive material included (1) bone-char phosphate, (2) zero-valent iron pellets, and (3) amorphous ferric oxyhydroxide coated gravel. An extensive monitoring network was installed in and around each PRB for collection of water samples, analysis of selected water-quality parameters, and monitoring of water levels. Water temperature, specific conductance, pH, Eh (oxidation-reduction potential), and dissolved oxygen were measured continuously within three different barrier materials, and in two monitoring wells. Water temperature and water level below land surface were electronically recorded every hour with pressure transducers. Data were collected from ground-water monitoring wells installed in and around the PRBs during 1996-98 and from surface-water sites in Fry Creek.

Utah↗

Determination of total mercury in biological and geological samples

The analytical chemist is faced with several challenges when determining mercury in biological and geological materials. These challenges include widespread mercury contamination, both in the laboratory and the environment, possible losses of mercury during sample preparation and digestion, the wide range of mercury values commonly observed, ranging from the low nanogram per gram or per liter for background areas to hundreds of milligrams per kilogram in contaminated or ore-bearing areas, great matrix diversity, and sample heterogeneity1. These factors can be naturally occurring or anthropogenic, but must be addressed to provide a precise and accurate analysis. Although there are many instrumental methods available for the successful determination of mercury, no one technique will address all problems or all samples all of the time. The approach for the determination of mercury used at the U.S. Geological Survey, Crustal Imaging and Characterization Team, Denver Laboratories, utilizes a suite of complementary instrumental methods when approaching a study requiring mercury analyses. Typically, a study could require the analysis of waters, leachates or selective digestions of solids, vegetation, and biological materials such as tissue, bone, or shell, soils, rocks, sediments, coals, sludges, and(or) ashes. No one digestion or sample preparation method will be suitable for all of these matrices. The digestions typically employed at our laboratories include: (i) a closed-vessel microwave method using nitric acid and hydrogen peroxide, followed by digestion/dilution with a nitric acid/sodium dichromate solution, (ii) a robotic open test-tube digestion with nitric acid and sodium dichromate, (iii) a sealed Teflon? vessel with nitric acid and sodium dichromate, (iv) a sealed glass bottle with nitric acid and sodium dichromate, or (v) open test tube digestion with nitric and sulfuric acids and vanadium pentoxide. The common factor in all these digestions is that they are very oxidative to ensure the conversion of all mercury forms into Hg (II). Each method of digestion has its advantages and limitations. The method of detection used in our laboratories involves a combination of an in-house, custom, classic continuous-flow cold-vapor atomic absorption spectrometry (CVAAS), a commercially available, automated, flow-injection and a continuous flow cold-vapor atomic fluorescence spectrometry (CV-AFS) systems, and a relatively new, automated and integrated approach where solid or liquid samples are thermally decomposed under an oxygen atmosphere (a nitrogen atmosphere is used for coals) and the released mercury vapor trapped onto a gold gauze and then thermally released into an AAS system. Other less frequently used instrumental methods available for the determination of mercury include inductively coupled plasma ? optical emission spectrometry (ICP-OES), inductively couple plasma ? mass spectrometry (ICP-MS) (both solution nebulization and laser ablation), and instrumental neutron activation analysis (INAA). Results from two case studies involving the determination of mercury in the challenging matrices of biological materials will be presented. These will include fillet, liver and stomach-content samples from grayling for a baseline/background study in Alaska, and samples of meat tissue and shell material from Tanner crabs from Glacier Bay, Alaska. These studies show that the method of digestion is more important than a very sensitive detection limit for mercury.

Open-File Report↗

Knowledge and Understanding of the Hydrogeology of the Salt Basin in South-Central New Mexico and Future Study Needs

The Salt Basin covers about 2,400 square miles of south-central New Mexico and extends across the State line into Texas. As much as 57 million acre-feet of ground water may be stored within the New Mexico part of the Salt Basin of which 15 million acre-feet are potentially potable and recoverable. Recent work suggests that the volume of ground water in storage within the New Mexico portion of the Salt Basin may be substantially greater than 57 million acre-feet. In this report, aquifers contained in the San Andres, Bone Spring, and Victorio Peak Limestones and in the Yeso, Hueco, and Abo Formations are collectively referred to as the carbonate aquifer. Porosity and permeability of the major aquifer are primarily determined by the density and interconnectedness of fractures and karstic solution channels. The spatial variability of these fractures and karstic features leads to a large spatial variability in hydraulic properties in the carbonate aquifer. Ground water generally moves southward away from recharge areas along the northern border of the Salt Basin and generally moves eastward to southeastward away from areas of distributed recharge on the Otero Mesa and the Diablo Plateau. Ground water originating from these recharge areas generally moves toward the central valley. Present day discharge is mostly through ground-water withdrawal for agricultural irrigation. A zone of relatively low hydraulic gradient, corresponding to the location of the Otero Break, extends from near the Sacramento River watershed southward toward Dell City, Texas. Ground water in the carbonate aquifer generally is very hard and has dissolved-solids concentrations ranging from 500 to 6,500 milligrams per liter. Substantial variability exists in current estimates of (1) ground-water recharge, (2) natural ground-water discharge, (3) the volume of ground water in storage, (4) the volume of recoverable ground water, (5) the conceptual model of ground-water flow, (6) the distribution of ground-water quality, and (7) the distribution of hydraulic characteristics. Future study could reduce uncertainty in these estimates and allow for better management of ground-water resources in the Salt Basin.

Open-File Report↗

Discharge, water temperature, and water quality of Warm Mineral Springs, Sarasota County, Florida: A retrospective analysis

Warm Mineral Springs, located in southern Sarasota County, Florida, is a warm, highly mineralized, inland spring. Since 1946, a bathing spa has been in operation at the spring, attracting vacationers and health enthusiasts. During the winter months, the warm water attracts manatees to the adjoining spring run and provides vital habitat for these mammals. Well-preserved late Pleistocene to early Holocene-age human and animal bones, artifacts, and plant remains have been found in and around the spring, and indicate the surrounding sinkhole formed more than 12,000 years ago. The spring is a multiuse resource of hydrologic importance, ecological and archeological significance, and economic value to the community. The pool of Warm Mineral Springs has a circular shape that reflects its origin as a sinkhole. The pool measures about 240 feet in diameter at the surface and has a maximum depth of about 205 feet. The sinkhole developed in the sand, clay, and dolostone of the Arcadia Formation of the Miocene-age to Oligocene-age Hawthorn Group. Underlying the Hawthorn Group are Oligocene-age to Eocene-age limestones and dolostones, including the Suwannee Limestone, Ocala Limestone, and Avon Park Formation. Mineralized groundwater, under artesian pressure in the underlying aquifers, fills the remnant sink, and the overflow discharges into Warm Mineral Springs Creek, to Salt Creek, and subsequently into the Myakka River. Aquifers described in the vicinity of Warm Mineral Springs include the surficial aquifer system, the intermediate aquifer system within the Hawthorn Group, and the Upper Floridan aquifer in the Suwannee Limestone, Ocala Limestone, and Avon Park Formation. The Hawthorn Group acts as an upper confining unit of the Upper Floridan aquifer. Groundwater flow paths are inferred from the configuration of the potentiometric surface of the Upper Floridan aquifer for September 2010. Groundwater flow models indicate the downward flow of water into the Upper Floridan aquifer in inland areas, and upward flow toward the surface in coastal areas, such as at Warm Mineral Springs. Warm Mineral Springs is located in a discharge area. Changes in water use in the region have affected the potentiometric surface of the Upper Floridan aquifer. Historical increase in groundwater withdrawals resulted in a 10- to 20-foot regional decline in the potentiometric surface of the Upper Floridan aquifer by May 1975 relative to predevelopment levels and remained at approximately that level in May 2007 in the area of Warm Mineral Springs. Discharge measurements at Warm Mineral Springs (1942–2014) decreased from about 11–12 cubic feet per second in the 1940s to about 6–9 cubic feet per second in the 1970s and remained at about that level for the remainder of the period of record. Similarity of changes in regional water use and discharge at Warm Mineral Springs indicates that basin-scale changes to the groundwater system have affected discharge at Warm Mineral Springs. Water temperature had no significant trend in temperature over the period of record, 1943–2015, and outliers were identified in the data that might indicate inconsistencies in measurement methods or locations. Within the regional groundwater basin, Warm Mineral Springs is influenced by deep Upper Floridan aquifer flow paths that discharge toward the coast. Associated with these flow paths, the groundwater temperatures increase with depth and toward the coast. Multiple lines of evidence indicate that a source of warm groundwater to Warm Mineral Springs is likely the permeable zone of the Avon Park Formation within the Upper Floridan aquifer at a depth of about 1,400 to 1,600 feet, or deeper sources. The permeable zone contains saline groundwater with water temperatures of at least 95 degrees Fahrenheit. The water quality of Warm Mineral Springs, when compared with other springs in Florida had the highest temperature and the greatest mineralized content. Warm Mineral Springs water is characterized by a slight-green color, with varying water clarity, low dissolved oxygen (indicative of deep groundwater), and a hydrogen sulfide odor. Water-quality samples detected ammonium-nitrogen and nitrates, but at low concentrations. The drinking water standard for nitrate adopted by the U.S. Environmental Protection Agency is 10 milligrams per liter, measured as nitrogen. Water samples collected at spring vents by divers on April 29, 2015, had concentrations of 0.9 milligram per liter nitrate-nitrogen at vent A and 0.04–0.05 milligram per liter at vents B, C, and D. Typically, the water clarity is highest in the morning (about 30 feet Secchi depth) and often decreases throughout the day. Analysis of existing data provided some insight into the hydrologic processes affecting Warm Mineral Springs; however, data have been sparsely and discontinuously collected since the 1940s. Continuous monitoring of hydrologic characteristics such as discharge, water temperature, specific conductance, and water-quality indicators, such as nitrate and turbidity (water clarity), would be valuable for monitoring and development of models of spring discharge and water quality. In addition, water samples could be analyzed for isotopic tracers, such as strontium, and the results used to identify and quantify the sources of groundwater that discharge at Warm Mineral Springs. Groundwater flow/transport models could be used to evaluate the sensitivity of the quality and quantity of water flowing from Warm Mineral Springs to changes in climate, aquifer levels, and water use.

Florida↗

Minimum average 7-day, 10-year flows in the Hudson River basin, New York, with release-flow data on Rondout and Ashokan reservoirs

Minimum average 7-day, 10-year flow at 67 gaging stations and 173 partial-record stations in the Hudson River basin are given in tabular form. Variation of the 7-day, 10-year low flow from point to point in selected reaches, and the corresponding times of travel, are shown graphically for Wawayanda Creek, Wallkill River, Woodbury-Moodna Creek, and the Fishkill Creek basins. The 7-day, 10-year low flow for the Saw Kill basin, and estimates of the 7-day, 10-year low flow of the Roeliff Jansen Kill at Ancram and of Birch Creek at Pine Hill, are given. Summaries of discharge from Rondout and Ashokan Reservoirs, in Ulster County, are also included. Minimum average 7-day, 10-year flow for gaging stations with 10 years or more of record were determined by log-Pearson Type III computation; those for partial-record stations were developed by correlation of discharge measurements made at the partial-record stations with discharge data from appropriate long-term gaging stations. The variation in low flows from point to point within the selected subbasins were estimated from available data and regional regression formula. Time of travel at these flows in the four subbasins was estimated from available data and Boning's equations.

Open-File Report↗

Generalized thickness of the surficial deposits above the confining bed overlying the Floridan Aquifer, Southwest Florida Water Management District

This map report presents the thickness of the surficial deposits overlying the upper confining bed of the Floridan aquifer in the Southwest Florida Water Management District. The surficial deposits range in thickness from less than 25 feet in the western part of the district to greater than 250 feet in the eastern part. The surficial deposits include sand, clayey sand, shell, and shelly marl that occur in the Holocene sand, Pleistocene marine terrace sand, and unconsolidated parts of the Fort Thompson Formation, Caloosahatchee Marl, Alachua Formation, and Bone Valley Formation. Lithologic logs and information from quarries were used in conjunction with an unpublished map prepared during an earlier investigation to compile this map at 1:250,000 scale. (Kosco-USGS)

Florida↗

Exploratory trench across the Pleasant Valley Fault, Nevada

An exploratory trench was excavated across the 1915 trace of the Pleasant Valley fault 60 km south of Winnemucca, Nevada, to get information on the history of recent displacements on a fault that had produced a major earthquake in historic time, and on the appearance of such a fault in a trench cut in gravels, sands and silts of an alluvial fan. The trench exposed 16 mappable sedimentary units and four soils, including three buried paleosols. The ages of the mapped units could not be narrowly defined but they are of late Quaternary age. Some rodent bones suggest a possible age of about 5,000 years for one of the higher stratigraphic units. The fault zone is very clearly represented in the trench, and, to the full 4-m depth of the trench, consists of a zone of fault rubble as much as 1.5 m wide. Two fractures outside the fault rubble show no vertical displacement. In addition to the fault rubble, the fault is conspicuous because several of the mapped units terminate abruptly against the rubble zone, and because the sediments southeast of the zone are coarser-grained than the sediments northwest of the zone. Maximum vertical component of the 1915 displacement was estimated to be 0.4–0.6 m based on topography and 0.5–0.6 m based on displacement of stratigraphic units including soils. Two or more episodes of vertical displacement, one of about 0.3 m and another totaling at least 1.15 m prior to 1915 are recorded and may have occurred in the last 5,000 years. These and other displacement events prior to 1915 are poorly dated, but that several did occur in late Pleistocene and Holocene time is certain. Lack of wedge-shaped deposits or concentrations of large clasts adjacent to the fault suggest that all displacements were produced in small increments of probably less than one meter each.

Nevada↗

Index of surface-water stations in Texas, January 1984

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Department of Water Resources, river authorities, cities, counties, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation, International Boundary and Water Commission, and others. Investigations are under the general direction of C. W. Boning, District Chief, Texas District. The Texas District office is located in the Federal Building, 300 East 8th Street, Austin, Texas 78701. As of January 1, 1984, 399 stream-gaging, 86 reservoir-contents, 19 stage, 2 periodic discharge through range, 42 flood-hydrograph partial-record, 15 floodprofile partial-record, 34 low-flow partial-record, 11 crest-stage partial-record, 11 tide-level , 60 daily chemical-qual ity, 27 continuous-recording water-quality, 187 periodic chemical-qual ity, 175 periodic organic-quality, 60 pesticides, 1 sediment, 43 periodic sediment, 109 periodic biological, 28 continuous-recording water temperature, and 37 national stream-quality accounting network stations were in operation. Plate 1 shows the location of surface-water streamflow or reservoircontent and chemical-qual ity or sediment stations in Texas. Plate 2 shows the location of partial-record surface-water stations. This index shows the station number and name, latitude and longitude, type of data collected, and the office principally responsible for the data collection (table 1). An 8-digit permanent numerical designation for gaging stations has been adopted on a nationwide basis; stations are numbered and listed in downstream order. In the downstream direction along the main stem, all stations on a tributary entering above a main-stem station are listed before that station. A tributary entering between two main-stem stations is listed between them. A similar order is followed in listing stations on first rank, second rank, and other ranks of tributaries. To indicate the rank of any tributary on which a gaging station is situated and the stream to which it is an immediate tributary, each indention in the listing of gaging stations represent one rank. This downstream order and system of indention show which gaging stations are on tributaries between any two stations on a main stem and the rank of the tributary on which each gaging station is situated. On plates 1 and 2 the 8-digit station number is abbreviated because of space limitation.

Texas↗

Distribution of fluoride in ground water of West Virginia

This report describes the results of a study by the U.S. Geological Survey, in cooperation with the West Virginia Geological and Economic Survey, to evaluate the distribution of fluoride in ground water of West Virginia. Fluoride is a natural chemical constituent in domestic and public water supplies in West Virginia. Fluoride concentrations of about 1.0 milligram per liter in drinking water are beneficial to dental health. Concentrations greater than 2.0 milligrams per liter, however, could harm teeth and bones. Fluoride concentra- tions in ground water of West Virginia range from less than 0.1 to 12 milligrams per liter. Fluoride concentrations that exceed 2.0 milligrams per liter are found in wells drilled to all depths, wells drilled in all topographic settings, and wells drilled into most geologic units. Most fluoride concentrations that exceed 2.0 milligrams per liter are located at sites clustered in the northwestern part of the State.

Open-File Report↗

Some American Cretaceous fish scales, with notes on the classification and distribution of Cretaceous fishes

Fish remains are extremely abundant in several Cretaceous formations of the Rocky Mountains and Great Plains, but except in the Niobrara formation of Kansas, a fish skeleton well enough preserved for description or identification is the greatest rarity. The fishes are represented by separate scales, in some places associated with a few vertebrae and other fragmentary bones or by isolated teeth. In the original descriptions of both the Mowry and the Aspen shales of Wyoming the presence of fish scales is mentioned as a characteristic feature. Fossils of other classes are usually very rare in beds containing many fish scales. Many of the scales are beautifully preserved and show varied forms and more or less complex structure.

Colorado;Missouri;Montana;Wyoming↗

Erosional and Depositional Aspects of Hurricane Camille in Virginia, 1969

Probably the worst natural disaster in central Virginia's recorded history was the flood resuiting from an 8-hour deluge of about 28 inches (710 mm) of rain on the night of August 19-20, 1969. This study examines some of the intensive sediment erosion and deposition that resulted from the storm and flood. Most of the 150 people whom the flood killed in this mountainous area died from broken bones and other blunt-force injuries, rather than by drowning. The transport of sediment and other debris by the water therefore was very significant in loss of life and in property damage. Erosion resulted mainly from debris avalanches down the mountain-sides and channel scour along streams and head-water tributaries. Total amounts of sediment yield from certain mountainous areas in Nelson County were about 3.2-4.6 million cubic feet per square mile, probably the equivalent of several thousand years of normal denudation. Characteristics of the debris avalanches were that (1) they usually followed pre-existing depressions on hillsides and occurred on slopes greater than 35 percent, (2) the upslope tip of the avalanche scar tended to be located at the steepest part of the hillside, where the convex slope merged with the concave or planar zone immediately below, (3) hillsides facing north, northeast and east were more susceptible to avalanching than slopes facing other directions, and (4) debris-avalanches caused rapid and devastating surges of water and sediment in the mountain-stream channels. Such surges in some instances temporarily blocked the channel flow upstream. Slightly more than half of the total sediment contributed to the stream system was from erosion of stream channels. Channel erosion was very irregularly distributed; some ravines 10-20 feet wide and 5-10 feet deep were scoured in places which formerly had only a very small channel, whereas other channels only a few hundred yards away experienced little or no channel erosion. By the use of figures for the total amount of sediment removed from a drainage basin and the duration of the storm, estimates were made of the storm-average sediment-transport rate at the mouth of various basins. For drainage basins ranging up to about 1.5 square miles, the estimated storm-average sediment-transport rates varied from practically nothing to as much as 172,000 pounds per second (7.4 million tons per day). The types of sediment deposits were (1) debris-avalanche deposits, rather rare, at the base of hillslopes, (2) mountain-stream channel deposits, usually in scattered sediment patches but locally occurring as large wedge-shaped deposits behind debris dams, (3) alluvial fans, (4) delta-like deposits at the junction of a stream and major highway, where water backed up during the flood due to plugging of a culvert, and (5) accretion deposits on flood plains. The highway deltas and some downstream flood-plain sediments consisted mostly of sand-sized grains, but the other types of deposits usually contained particles ranging from silt or clay to boulders 5-10 feet in diameter. Changes in grain size and in volume of deposition with distance downstream were measured, and sedimentary features of the various types of deposits are described.

Professional Paper↗

Injection-Site Reactions in Wild Horses (Equus caballus) Receiving an Immunocontraceptive Vaccine

The U.S. Geological Survey and the Bureau of Land Management are conducting research on the efficacy of the immunocontraceptive agent porcine zona pellucida (PZP) in reducing fertility of wild horses (Equus caballus). As an antigen, PZP stimulates antibody production when injected into many mammalian species. These antibodies bind to the external surface of the ovum, preventing fertilization. By itself, PZP is only weakly immunogenic and is therefore delivered with an adjuvant, most commonly one of the Freund adjuvants, designed to further stimulate antibody production. Freund's complete adjuvant (FCA) in particular is known to be very effective, but may also be associated with undesirable side effects such as formation of abscesses at injection sites. Such reactions may be exacerbated when accompanied by the additional trauma of a remotely delivered dart. Because horses in our three study herds were individually identifiable by color markings and harem association, we were able to monitor mares for injection-site reactions (abscesses, nodules, swelling, and stiffness) following inoculation with PZP. In 100 injections delivered by hand we observed a single nodule, two instances of swelling, and no other reactions. In two herds that received remotely delivered (dart) injections, the frequency of reactions was about 1 and 6 percent for abscesses, 25 percent for nodules (both herds), 11 and 33 percent for swelling, and 1 and 12 percent for stiffness. Abscesses were too infrequent to allow meaningful analysis of the relation to covariates, but for the other types of reactions we used logistic regression to examine the relation of occurrence to the delivery method (rifle or CO2-powered blowgun), adjuvant (FCA, Freund's modified adjuvant, and Freund's incomplete adjuvant), dart trauma (normal or abnormal), and age of mare. Abnormal dart trauma included cases where the dart hit bone or the needle broke off. We found strong evidence (odds ratio = 5.023, P = 0.001) for a higher probability of occurrence of swelling when darts were delivered by blowgun. We found some evidence (odds ratio = 8.729, P = 0.07) that abnormal dart trauma led to a higher frequency of nodule formation. Nodules were the most common reactions observed and often persisted for a year or more, but in our observations they did not appear to change any animal's range of movement or locomotor patterns and in most cases did not appear to differ in magnitude from naturally occurring injuries or scars. We were unable to perform histological examinations of these nodules, but they may be similar to granulomas reported by other investigators following administration of Freund's adjuvant.

Scientific Investigations Report↗

The quantitative determination of calcite associated with the carbonate-bearing apatites

The CO 2 combined as calcite in carbonate-bearing apatites as been distinguished from that combined as carbonate-apatite, or present in some form other than calcite, by use of X-ray powder patterns, differential thermal analyses, and differential solubility tests. These methods were applied to several pure apatite minerals, to one fossil bone, and to a group of phosphorites from the Phosphoria formation of Permian age from Trail Canyon and the Conda mine, Idaho, and the Laketown district, Utah. With the exceptions of pure fluorapatite, pure carbonate-flueorapatite, and one phosphorite from Trail Canyon, these substances contain varying amounts of calcite, but in all the samples an appreciable part of the carbonite content is not present as calcite. The results of solubility tests, in which the particle size of sample and the length of solution time were varied, imply that the carbonate content is not due to shielded calcite entrapped along an internal network of surfaces.

Idaho;Utah↗

The geology of the Florida land-pebble phosphate deposits

The land-pebble phosphate district is on the Gulf Coastal Plain of Florida. The phosphate deposits are in the Bone Valley formation, dated Pliocene by most writers. These strata overlie the Miocene Hawthorn formation and are overlain by consolidated sands 3 to 20 feet thick. The minable phosphate deposits, called “matrix” in the district, range from a featheredge to about 50 feet in thickness and consist of phosphatic pellets and nodules, quartz sand, and montmorillonitic clay in about equal proportions. Locally the matrix displays cross-bedding and horizontal laminations, but elsewhere it is structureless. The phosphorite particles, composed largely of carbonate-fluorapatite, range in diameter from less than 0.1 mm to about 60 cm and in P 2 O 5 content from 30 to 36 percent. Coarse-pebble deposits, containing 30 to 34 percent P 2 O 5 are found mainly on basement highs; and fine-pebble deposits, containing 32 to 36 percent P 2 O 5 are, are found in basement lows. Deposits in the northern part of the field contain more phosphate particles and their P 2 O 5 content is higher than those in the southern part. The upper part of the phosphatic strata is leached to an advanced degree and consists of quartz sand and clay-sized particules of pseudowavellite and wavellite. The leached zone ranges in thickness from a featheredge to 60 feet. The origin of the land-pebble deposits is incompletely known. Possible modes of origin are a residuum of Miocene age, or a reworked residuum of Pliocene or Quaternary age.

Florida↗

Geologic features of areas of abnormal radioactivity south of Ocala, Marion County, Florida

Areas of abnormal radioactivity south of Ocala, Marion County, Fla., discovered in 1953 by aerial survey, were investigated by surface examination and by 10 power auger drill holes. Inter-bedded clay, clayey sand, and uraniferous phosphorite occur in the areas of anomalous radioactivityo Miocene fossils occur at three localities in these beds which are evidently outliers- of Miocene sediments on the Ocala limestone of Eocene age. The preserved outliers are southwest of the main belt of Miocene sediments. The principal uraniferous rocks are clayey, sandy, pellet phosphori1te that occurs in beds a few feet thick, and very porous, phosphatic sand rock which makes abundant float at many places. Apatite forms the phosphate pellets in the unweathered phosphorite. The very porous, phosphatic sand rock is the highly leached residuum of the pellet phosphorite and is composed mainly of quartz, kaolinite, wavellite, and crandallite (pseudowavellite). It closely resembles the aluminum phosphate rock of the 'leached zone' of the Bone Valley formation in the land-pebble phosphate district.

Trace Elements Memorandum↗