Flow and chemical characteristics of the St. Johns River at Jacksonville, Florida

This report will be of substantial value to water managers in developing the St. Johns River as a multiple resource. Evaluation of the capacity of the river to accept pollutants without adversely affecting other uses requires detailed data of flow and chemical characteristics and an understanding of how they interact. (66 page document

Dendrophoma leaf blight of strawberry

Cover title.Includes bibliographical references

A novel design concept for space-based polar remote sensing

Space-based remote sensing of the Earth is conducted from a fleet of spacecraft in two basic orbital positions, near-polar low-Earth orbits and geosynchronous orbits, with each offering its own advantages and disadvantages. Low-Earth orbits provide high-resolution observations at the expense of large-scale contextual information, while geosynchronous orbits provide near-global, continuous coverage at reduced resolutions. However, due to the rapidly decreasing horizontal resolution data-products derived from geosynchronous orbits are of degraded value beyond approximately 55 degrees of latitude. A novel mission design is introduced to enable continuous observation of all longitudes at latitudes between 55 and 90 degrees with an observation zenith angle of less than 60 degrees, without the use of composite images. A single Soyuz launch is used to deliver three spacecraft to 12-hr, highly eccentric true-polar orbits with apogee at 40170 km and electric propulsion is used to maintain the orbit apse-line coincident with the Earth’s poles. It is shown that the science payload mass can be traded against the mission duration, with a payload mass varying between 120 – 90 kg for mission durations between 3 – 5 years, respectively. It is further shown that the payload would have approximately of 2kW of power available during operations as the electric propulsion system is not operated at these times. Whilst the payload mass is less than a typical remote sensing platform in geosynchronous orbit it is considered that the concept would offer an excellent technology demonstrator mission for operational missions, whilst also enabling unique and valuable science

Evaluating research - Peer review team assessment and journal-based bibliographic measures: New Zealand PBRF research output scores in 2006

This paper concerns the relationship between the assessment of the research of individual academics by peer or expert review teams with a variety of bibliometric schemes based on journal quality weights. Specifically, for a common group of economists from New Zealand departments of economics the relationship between Performance-Based Research Fund (PBRF) Research Output measures for those submitting new research portfolios in 2006 are compared with evaluations of journal based research over the 2000-2005 assessment period. This comparison identifies the journal weighting schemes that appear most similar to PBRF peer evaluations. The paper provides an indication of the ‘power or aggressiveness’ of PBRF evaluations in terms of the weighting given to quality. The implied views of PBRF peer review teams are also useful in assessing common assumptions made in evaluating journal based research

Mineralization and Hydrocarbon Emplacement in the Cambrian-Ordovician Mascot Dolomite of the Knox Group in South-Central Kentucky

The Mascot Dolomite, the upper unit of the Cambrian-Ordovician Knox Group, is a major host for Mississippi Valley-type ore deposits and petroleum in south-central Kentucky. The Mascot was deposited on a broad, shallow platform that exhibited unusually uniform conditions of deposition, ranging from supratidal to shallow subtidal environments. The formation has a complex diagenetic history, including several stages of dolomitization, silicification, solution, and brecciation. Diagenesis and, to some extent, deposition were influenced by Early Ordovician tectonic activity. Tectonic activity influenced development of a regional unconformity during Middle Ordovician time. Evidence of this tectonic activity includes up to 300 feet of erosional relief on the Mascot surface and thinning in the interval between the internal marker beds across the Cincinnati and Waverly Arches. The development of an erosional unconformity at the top of the Knox Group and its resulting paleoaquifer and karst system created diagenetic changes, migration avenues, and solution-collapse breccias that controlled subsequent fluid migration and accumulations of base metals and hydrocarbons. The location of breccia-hosted ores was influenced by major and minor structural features and paleotopography. Breccia development is related to the presence and subsequent dissolution of limestone (now represented by dolomite) and a dolomite-limestone transition zone. Base-metal mineralization (dominantly sphalerite) is associated with late-stage brecciation and stromatolitic units, which commonly are silicified. Several oil pools produce from Knox paleotopographic highs, and production seems to be related to the presence of fractures and diagenetically enhanced porosity. A distinct positive relationship exists between ore and petroleum accumulation. Locations of ore deposits are related to circular features that can be recognized on remotely sensed Landsat imagery, and areas of petroleum accumulation appear to be related to paleolinear trends

Mineralogy and Chemistry of Rare Earth Elements in Alkaline Ultramafic Rocks and Fluorite in the Western Kentucky Fluorspar District

Rare earth elements, or REE, are used in modern society in televisions, computers, cellphones, military equipment, and smart weapons systems. These metals are also used by the medical industry in magnetic resonance imaging and in medical products. The igneous rocks in the Western Kentucky Fluorspar District of the New Madrid Rift System are considered alkaline ultramafic rocks that are slightly enriched in REE. These rocks are rare and only occur in several hundred locations in the world. They have a complex history of emplacement, fractionation, metasomatism, and alteration, and are overprinted with Mississippi Valley-type mineralization. They are classified as lamprophyres and peridotites, and the rare mineralogy of the district suggests that there may be other facies of these rocks, such as carbonatite, kimberlite, and lamproite. The rare minerals wüstite and moissanite also suggest a deep lithospheric and asthenospheric mantle contribution to these igneous rocks and raise the level of interest in the igneous complex, which occurs in a Midcontinent rift system. The petrogenesis of these rocks allows them to fractionate and concentrate REE by natural means, and although this study’s limited dataset did not reveal any economic deposits, there could still be economic quantities in western Kentucky. If higher concentrations of REE are found in the igneous dikes in the area, the economics and mining of the dikes might be feasible. Millions of tons of fluorite and thousands of tons of sphalerite, galena, and barite have been mined in the district, and small amounts of REE have been detected in the fluorite. Other elements of interest are titanium, niobium, iridium, cobalt, molybdenum, zirconium, and lithium, which suggest other elemental phases of mineralization. Many of these rare minerals and elements have never been described in the Western Kentucky Fluorspar District, and future research is warranted to further classify them

Master of Science

thesisThis report presents data and conclusions concerning the role of low-angle faulting in the formation of the Thermo Hot Springs Known Geothermal Resource Area (KGRA) and the effects that such faulting may have on fluid flow and production. The conclusions are that the KGRA is formed by a low-angle normal fault that juxtaposes Mesozoic and upper Paleozoic sedimentary rock in the upper plate over metamorphic rock and granite. The Mesozoic section is in turn overlain by a sequence of Tertiary to Quaternary volcanic and sedimentary deposits. High-angle normal faults offset the sedimentary and volcanic sections, and in some, if not all, cases penetrate and offset the low-angle detachment fault. These high-angle normal faults may hydraulically compartmentalize the reservoir but also provide pathways for fluids to ascend upwards from beneath the detachment fault. The implications of the low-angle normal or detachment fault structure are significant: (1) The Thermo Hot Springs KGRA has striking similarities to the structures and stratigraphy that are exposed in the southern Mineral Mountains, which provide an excellent outcrop analog for studying the nature of the structures and fluid conduits that presumably occur at depth in the KGRA. There is good reason to suspect that the Cave Canyon detachment fault exposed in the southern Mineral Mountains is the same or similar structure as the detachment fault within the Thermo Hot Springs KGRA. The similarities include lower fault plate granitic and metamorphic rocks, hydrothermally altered cataclasite within the detachment fault zone, essentially an identical stratigraphy within the upper plate of the detachment fault, and a mosaic of north and east trending high-angle normal faults, some of which penetrate and offset the detachment fault. (2) The low-angle detachment fault model for KGRA structure has regional implications for geothermal prospecting in the Basin and Range terrain of southwestern Utah. This region is underlain by several known or suspected detachment normal faults of middle to late Tertiary age, which may act to laterally channel hot fluids at depth over large areas with little surface expression, such as springs or tufa mounds, except where the low-angle faults are breached by younger faulting

Foundation Problems and Pyrite Oxidation in the Chattanooga Shale, Estill County, Kentucky

Pyrite oxidation in the Chattanooga Shale has caused serious foundation problems in numerous buildings and structures in Estill County, Ky. Pyrite oxidizes and various secondary sulfates form when excavated shale or shale fill are used in foundations. These secondary sulfates are water- and humidity-sensitive and can form when only minor amounts of water are present in foundation materials. These sulfates form by crystal growth and expand by volume change, which causes subsequent soil expansion and heaving of any foundation materials when the materials are confined. Several structures have undergone expensive remediation to repair damaged sidewalks, floors, walls, and foundations. Zones of high concentrations of pyrite occur in the Chattanooga Shale across the state, and these mineral zones may be responsible for the high pyrite content in Estill County