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Articles 331 - 360 of 442
Full-Text Articles in Earth Sciences
Generalized Geologic Map For Land-Use Planning: Bourbon County, Kentucky, Daniel I. Carey
Generalized Geologic Map For Land-Use Planning: Bourbon County, Kentucky, Daniel I. Carey
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Generalized Geologic Map For Land-Use Planning: Meade County, Kentucky, Daniel I. Carey, Richard E. Sergeant, Peter Eclov
Generalized Geologic Map For Land-Use Planning: Meade County, Kentucky, Daniel I. Carey, Richard E. Sergeant, Peter Eclov
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Generalized Geologic Map For Land-Use Planning: Clay County, Kentucky, Oscar B. Davidson, Daniel I. Carey, John Storm
Generalized Geologic Map For Land-Use Planning: Clay County, Kentucky, Oscar B. Davidson, Daniel I. Carey, John Storm
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Generalized Geologic Map For Land-Use Planning: Mccreary County, Kentucky, Daniel I. Carey, Randall L. Paylor, Bethany L. Overfield
Generalized Geologic Map For Land-Use Planning: Mccreary County, Kentucky, Daniel I. Carey, Randall L. Paylor, Bethany L. Overfield
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Generalized Geologic Map For Land-Use Planning: Owen County, Kentucky, Daniel I. Carey, Cam Flanders
Generalized Geologic Map For Land-Use Planning: Owen County, Kentucky, Daniel I. Carey, Cam Flanders
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Generalized Geologic Map For Land-Use Planning: Grayson County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey
Generalized Geologic Map For Land-Use Planning: Grayson County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Generalized Geologic Map For Land-Use Planning: Trimble County, Kentucky, Daniel I. Carey, Bart Davidson
Generalized Geologic Map For Land-Use Planning: Trimble County, Kentucky, Daniel I. Carey, Bart Davidson
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Generalized Geologic Map For Land-Use Planning: Harrison County, Kentucky, Daniel I. Carey, Richard A. Smath
Generalized Geologic Map For Land-Use Planning: Harrison County, Kentucky, Daniel I. Carey, Richard A. Smath
Map and Chart--KGS
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.
Strain Accumulation Across The Carrizo Segment Of The San Andreas Fault, California: Impact Of Laterally Varying Crustal Properties, Gina Schmalzle, Timothy H. Dixon, Rocco Malservisi, Rob Govers
Strain Accumulation Across The Carrizo Segment Of The San Andreas Fault, California: Impact Of Laterally Varying Crustal Properties, Gina Schmalzle, Timothy H. Dixon, Rocco Malservisi, Rob Govers
School of Geosciences Faculty and Staff Publications
Major strike slip faults juxtapose geologically dissimilar terrain which may vary in mechanical properties, leading to an asymmetric pattern of strain accumulation. We present new GPS data on the Carrizo segment of the San Andreas Fault, separating the Salinian block southwest of the fault from Franciscan terrane northeast of the fault, to better quantify asymmetric strain accumulation. We also present a series of finite element models to investigate the possible role of variable elastic layer thickness and material properties of the upper crust. The geodetic data are well fit with a simple model comprising a weak upper crustal zone 10–25 …
Pelagic Functional Group Modeling: Progress, Challenges And Prospects, Raleigh R. Hood, Edward A. Laws, Robert A. Armstrong, Nicholas R. Bates, Christopher W. Brown, Craig A. Carlson, Fei Chai, Scott C. Doney, Paul G. Falkowski, Richard A. Feely, Marjorie A. M. Friedrichs
Pelagic Functional Group Modeling: Progress, Challenges And Prospects, Raleigh R. Hood, Edward A. Laws, Robert A. Armstrong, Nicholas R. Bates, Christopher W. Brown, Craig A. Carlson, Fei Chai, Scott C. Doney, Paul G. Falkowski, Richard A. Feely, Marjorie A. M. Friedrichs
CCPO Publications
In this paper, we review the state of the art and major challenges in current efforts to incorporate biogeochemical functional groups into models that can be applied on basin-wide and global scales, with an emphasis on models that might ultimately be used to predict how biogeochemical cycles in the ocean will respond to global warming. We define the term "biogeochemical functional group" to refer to groups of organisms that mediate specific chemical reactions in the ocean. Thus, according to this definition, "functional groups" have no phylogenetic meaning-these are composed of many different species with common biogeochemical functions.
Substantial progress has …
Flow Resistance Dynamics In Step-Pool Stream Channels: 1. Large Woody Debris And Controls On Total Resistance, Andrew C. Wilcox, Ellen E. Wohl
Flow Resistance Dynamics In Step-Pool Stream Channels: 1. Large Woody Debris And Controls On Total Resistance, Andrew C. Wilcox, Ellen E. Wohl
Geosciences Faculty Publications
Flow resistance dynamics in step-pool channels were investigated through physical modeling using a laboratory flume. Variables contributing to flow resistance in step-pool channels were manipulated in order to measure the effects of various large woody debris (LWD) configurations, steps, grains, discharge, and slope on total flow resistance. This entailed nearly 400 flume runs, organized into a series of factorial experiments. Factorial analyses of variance indicated significant two-way and three-way interaction effects between steps, grains, and LWD, illustrating the complexity of flow resistance in these channels. Interactions between steps and LWD resulted in substantially greater flow resistance for steps with LWD …
Flow Resistance Dynamics In Step-Pool Channels: 2. Partitioning Between Grain, Spill, And Woody Debris Resistance, Andrew C. Wilcox, Jonathan M. Nelson, Ellen E. Wohl
Flow Resistance Dynamics In Step-Pool Channels: 2. Partitioning Between Grain, Spill, And Woody Debris Resistance, Andrew C. Wilcox, Jonathan M. Nelson, Ellen E. Wohl
Geosciences Faculty Publications
In step-pool stream channels, flow resistance is created primarily by bed sediments, spill over step-pool bed forms, and large woody debris (LWD). In order to measure resistance partitioning between grains, steps, and LWD in step-pool channels we completed laboratory flume runs in which total resistance was measured with and without grains and steps, with various LWD configurations, and at multiple slopes and discharges. Tests of additive approaches to resistance partitioning found that partitioning estimates are highly sensitive to the order in which components are calculated and that such approaches inflate the values of difficult-to-measure components that are calculated by subtraction …
Lithofacies, Architecture And Sequence Stratigraphic Interpretation Of The Upper Pennsylvanian Indian Cave Sandstone, Northern Midcontinent Shelf, U.S.A. (Southeastern Nebraska)., Steven A. Fischbein
Lithofacies, Architecture And Sequence Stratigraphic Interpretation Of The Upper Pennsylvanian Indian Cave Sandstone, Northern Midcontinent Shelf, U.S.A. (Southeastern Nebraska)., Steven A. Fischbein
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
The Virgilian “Indian Cave Sandstone” (ICS) is herein redefined as at least four incised valley fills (IVFs) of at least two different ages. These IVFs are composed of irregularly bounded, tabular-lenticular units of trough cross-bedded sandstone, grading vertically into tabular-lenticular units of mudstone-and-sandstone-dominated heterolith. Three IVFs, wider (< 2 km) than they are deep (> 30 m), are composed of multiple storeys grading upward from fluvial-to-estuarine facies to upper-estuarine facies. Storey boundaries are delineated by bounding surfaces underlying conglomerates with heterolithic clasts. One IVF (Honey Creek, NE) is smaller than the others, (> 0.5 km wide and > 25 m deep) and appears to be composed of a …
Plant Paleoecology Of The Late Devonian Red Hill Locality, North-Central Pennsylvania, An Archaeopteris-Dominated Wetland Plant Community And Early Tetrapod Site., Walter L. Cressler Iii
Plant Paleoecology Of The Late Devonian Red Hill Locality, North-Central Pennsylvania, An Archaeopteris-Dominated Wetland Plant Community And Early Tetrapod Site., Walter L. Cressler Iii
Earth & Space Sciences Faculty Publications
The Late Devonian Red Hill locality in north-central Pennsylvania contains an Archaeopteris-dominated plant fossil assemblage, a diverse fossil fauna, and an extensive sedimentary sequence ideal for investigating the landscapes and biotic associations of the earliest forest ecosystems. Sedimentological analysis of the main plantfossil bearing layer at Red Hill indicates that it was a fl ood-plain pond. A seasonal wet-and-dry climate is indicated by well-developed paleovertisols. The presence of charcoal interspersed with plant fossils indicates that fi res occurred in this landscape.Fires appear to have primarily affected the fern Rhacophyton. The specifi city of the fires, the distribution profi …
Stratigraphic And Palaeoenvironmental Significance Of Bartonian–Priabonian (Middle–Late Eocene) Microfossils From The Başçeşme Formation, Denizli Province, Western Anatolia, M. Serkan Akki̇raz, Funda Akgün, Sefer Örçen, Angela Bruch, Volker Mosbrugger
Stratigraphic And Palaeoenvironmental Significance Of Bartonian–Priabonian (Middle–Late Eocene) Microfossils From The Başçeşme Formation, Denizli Province, Western Anatolia, M. Serkan Akki̇raz, Funda Akgün, Sefer Örçen, Angela Bruch, Volker Mosbrugger
Turkish Journal of Earth Sciences
This study explains the stratigraphical and palaeoenvironmental significance of Bartonian-Priabonian (Middle-Late Eocene) fossils, the fauna and flora obtained from the Başçeşme formation of the Çardak-Tokça basin (western Anatolia). The studied sequence is an outcrop from the Başçeşme formation, deposited in a shallow-marine to coastal environment without stratigraphic breaks. Forty genera and 58 species have been recognized in the palynological assemblage of the Başçeşme formation. A well-preserved diverse palynomorph and foraminiferal assemblages yield the Middle-Late Eocene age for the Başçeşme formation. In western Anatolia, mangrove elements Nypa and Pelliciera have been first recorded in this study. The pollen of Mauritia and …
Mineralogical Characterization Of Protolith And Fault Rocks From The Safod Main Hole, John G. Solum, Stephen H. Hickman, David A. Lockner, Diane E. Moore, Ben A. Van Der Pluijm, Anja M. Schleicher, James P. Evans
Mineralogical Characterization Of Protolith And Fault Rocks From The Safod Main Hole, John G. Solum, Stephen H. Hickman, David A. Lockner, Diane E. Moore, Ben A. Van Der Pluijm, Anja M. Schleicher, James P. Evans
Geosciences Faculty Publications
Washed cuttings provide a continuous record of the rocks encountered during drilling of the main hole of the San Andreas Fault Observatory at Depth (SAFOD). Both protolith and fault rocks exhibit a wide variety of mineral assemblages that reflect variations in some combination of lithology, P-T conditions, deformation mechanisms, and fluid composition and abundance. Regions of distinct neomineralization bounded by faults may record alteration associated with fluid reservoirs confined by faults. In addition, both smectites occurring as mixed-layer phases and serpentine minerals are found in association with active strands of the San Andreas Fault that were intersected during drilling, although …
Structural Evolution And Vorticity Of Flow During Extrusion And Exhumation Of The Greater Himalayan Slab, Mount Everest Massif, Tibet/Nepal: Implications For Orogen-Scale Flow Partitioning, M. J. Jessup, R. D. Law, M. P. Searle, Mary S. Hubbard
Structural Evolution And Vorticity Of Flow During Extrusion And Exhumation Of The Greater Himalayan Slab, Mount Everest Massif, Tibet/Nepal: Implications For Orogen-Scale Flow Partitioning, M. J. Jessup, R. D. Law, M. P. Searle, Mary S. Hubbard
Geosciences Faculty Publications
The Greater Himalayan Slab (GHS) is composed of a north-dipping anatectic core, bounded above by the South Tibetan detachment system (STDS_ and below by the Main Central thrust zone (MCTZ). Assuming simultaneous movement on the MCTZ and STDS, the GHS can be modelled as a southward-extruding wedge or channel. New insights into extrusion-related flow with the GHS emerge from detailed kinematic and vorticity analyses in the Everest region. At the highest structural levels, mean kinematic vorticity number (Wm) estimates of 0.74-0.91 (c. 45-28% pure shear) were obtained from sheared Tethyan limestone and marble from the Yellow Band on Mount Everest. …
Pyritized Tube Feet In A Protasterid Ophiuroid From The Upper Ordovician Of Kentucky, U.S.A., Alexander Glass
Pyritized Tube Feet In A Protasterid Ophiuroid From The Upper Ordovician Of Kentucky, U.S.A., Alexander Glass
All Faculty Scholarship for the College of the Sciences
A single specimen of the protasterid ophiuroid Protasterina flexuosa from the Kope Formation (Cincinnatian, Upper Ordovician) of Kentucky exhibits three−dimensionally pyritized tube feet. This represents the first report of soft−tissue preservation in an echinoderm from the type−Cincinnatian series. The tube feet are solid and lack all internal structure. They consist of aggregated masses of small euhedral to subhedral pyrite crystals suggesting that pyritization, although decay−induced and mediated, did not necessarily replicate soft−tissues but might instead have formed inside the void−spaces left behind during the decay process. The discovery of pyritized soft−tissue as delicate as ophiuroid tube feet suggests that similar …
Geochronology And Tectonic Significance Of Middle Proterozoic Granitic Orthogneiss, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Juhn G. Liou, D. K. Bird, C. L. Wu
Geochronology And Tectonic Significance Of Middle Proterozoic Granitic Orthogneiss, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Juhn G. Liou, D. K. Bird, C. L. Wu
All Faculty Scholarship for the College of the Sciences
Amphibolite-facies para- and orthogneisses near Dulan, in the southeast part of the North Qaidam terrane, enclose minor ultra-high pressure (UHP) eclogite and peridotite. Field relations and coesite inclusions in zircons from paragneiss suggest that felsic, mafic, and ultramafic rocks all experienced UHP metamorphism and a common amphibolite-facies retrogression. Ion microprobe U–Pb and REE analyses of zircons from two granitic orthogneisses indicate magmatic crystallization at 927 ± Ma and 921 ± 7 Ma. Zircon rims in one of these samples yield younger ages (397–618 Ma) compatible with partial zircon recrystallization during in-situ Ordovician-Silurian eclogite-facies metamorphism previously determined from eclogite and paragneiss …
Genetic Stratigraphy And Geochronology Of Last Interglacial Shorelines On The Central Coast Of South Carolina, Russell Willis
Genetic Stratigraphy And Geochronology Of Last Interglacial Shorelines On The Central Coast Of South Carolina, Russell Willis
LSU Master's Theses
This study investigated the shallow subsurface of the Lower Coastal Plain of South Carolina in order to determine the sea-level history and stratigraphic architecture preserved within several emergent shoreline complexes. The absolute age of each shoreline complex was estimated using single-aliquot regenerative-dose (SAR) optically stimulated luminescence (OSL) techniques. The resulting geochronology was incorporated into a high-resolution stratigraphic framework defined by ground penetrating radar calibrated with deep sediment cores, many of which contain a complete sequence of highstand deposition. Three emergent barrier complexes were identified within the Lower Talbot, Pamlico, and Princess Anne terraces, and assigned to sea-level highstands during interglacial …
Multiple Phases Of Tertiary Extension And Synextensional Deposition Of The Miocene–Pliocene Salt Lake Formation In An Evolving Supradetachment Basin, Malad Range, Southeast Idaho, U.S.A., S. P. Long, P. K. Link, Susanne U. Janecke, D. W. Rodgers, M. E. Perkins, C. M. Fanning
Multiple Phases Of Tertiary Extension And Synextensional Deposition Of The Miocene–Pliocene Salt Lake Formation In An Evolving Supradetachment Basin, Malad Range, Southeast Idaho, U.S.A., S. P. Long, P. K. Link, Susanne U. Janecke, D. W. Rodgers, M. E. Perkins, C. M. Fanning
Geosciences Faculty Publications
The extensional history of the Malad and Bannock ranges in southeast Idaho and northern Utah involves multiple phases of Tertiary normal faulting and synextensional deposition. Detailed geologic mapping, structural and stratigraphic analyses, and geochronologic data from this study elucidate previously defined deformational events in the region, and define two new extensional episodes.
The largest-magnitude extension took place along low-angle normal faults of the ∼10–4-Ma Bannock detachment system, with concurrent sedimentation of the Miocene–Pliocene Salt Lake Formation in a regionally continuous supradetachment basin. This basin developed by ∼10.2 Ma, and was preceded by two phases of smaller-magnitude, aerially restricted normal faulting …
Evaluating Surface Area-Basin Volume Relationships For Prairie Potholes, Mike A. Davis
Evaluating Surface Area-Basin Volume Relationships For Prairie Potholes, Mike A. Davis
Theses and Dissertations
Establishing a relationship between surface area and volume of prairie potholes provides a simple method to estimate changes in water storage across the landscape. Applications include better prediction of floods and improved design for wetland restoration. Length, width, depth, surface area, and volumes were surveyed for eighty two potholes within the upper Turtle River watershed which lies sixty kilometers west of Grand Forks, ND. These data were used to determine the relationship and uncertainty between pothole surface and volume. Chi squared tests defined distributions of each variable. F and T statistical tests resolved similarities in variance and mean. The eighty …
Taphonomic And Sedimentologic Study Of The Cretaceous Tepee Buttes Limestone, Hilary G. Close
Taphonomic And Sedimentologic Study Of The Cretaceous Tepee Buttes Limestone, Hilary G. Close
Honors Papers
The Tepee Buttes methane seep deposits exist today as topographically defined limestone features in the surrounding Pierre Shale of the Campanian Western Interior Seaway. The present sloping surface has previously been assumed to be indicative of original seep structure, and biofacies were interpreted as roughly ringing a central vent core. Contradictory field observations in this study have prompted a more detailed taphonomic approach to the Tepee Buttes limestone, and certain depositional features such as reworked horizontal shell beds were noted and examined in detail for the first time. The results of a taphonomic and sedimentologic analysis reveal a complex history …
Does The Great Valley Group Contain Jurassic Strata? Reevaluation Of The Age And Early Evolution Of A Classic Forearc Basin, Kathleen D. Surpless, S. A. Graham, J. A. Covault, J. L. Wooden
Does The Great Valley Group Contain Jurassic Strata? Reevaluation Of The Age And Early Evolution Of A Classic Forearc Basin, Kathleen D. Surpless, S. A. Graham, J. A. Covault, J. L. Wooden
Earth and Environmental Geosciences Faculty Research
The presence of Cretaceous detrital zircon in Upper Jurassic strata of the Great Valley Group may require revision of the lower Great Valley Group chronostratigraphy, with significant implications for the Late Jurassic–Cretaceous evolution of the continental margin. Samples (n = 7) collected from 100 km along strike in the purported Tithonian strata of the Great Valley Group contain 20 Cretaceous detrital zircon grains, based on sensitive high-resolution ion microprobe age determinations. These results suggest that Great Valley Group deposition was largely Cretaceous, creating a discrepancy between biostratigraphy based on Buchia zones and chronostratigraphy based on radiometric age dates. These …
Fluvial Response To Intra-Canyon Lava Flows, Owyhee River, Southeastern Oregon, Cooper Cooke Brossy
Fluvial Response To Intra-Canyon Lava Flows, Owyhee River, Southeastern Oregon, Cooper Cooke Brossy
All Master's Theses
At least six lava flows have entered the Owyhee River Canyon north of Rome, Oregon, since the Pliocene and directly impacted the Owyhee River. The effects on the river of the two youngest lava flows, the West Crater (60–80 ka) and Saddle Butte (> 60–90 ka), are readily apparent. These two lava flows entered a paleo-Owyhee Canyon several kilometers wide via three different tributary drainages. The flows dammed the Owyhee River, created lakes, and effectively confined the river to the opposite side of the valley from the flows’ entrance. Lava from these flows filled a paleo-Owyhee Canyon to depths of …
Deciphering The Signature Of Magma Mixing: Examples From The Castle Creek Eruptive Period, Mount St. Helens, Washington, Seth Taylor Mattos
Deciphering The Signature Of Magma Mixing: Examples From The Castle Creek Eruptive Period, Mount St. Helens, Washington, Seth Taylor Mattos
All Master's Theses
Mount St. Helens (MSH) volcano in southwestern Washington has intermittently erupted dacitic products for the last 40,000 years. On limited occasions, the volcano has produced andesite lava flows, and during one short-lived period, basaltic lava flows. This time interval has been termed the Castle Creek eruptive period and occurred between approximately 2500 and 1700 years B.P. The Castle Creek period erupted dacite, andesite and basalt within this short span of time. Andesite and dacite eruptions dominate the first approximately 700 years of the period, and all basaltic units were erupted in approximately the last 100 years of the period. This …
Soil Phosphorus Levels In Residential Lawns And Comparisons Among Four Land Uses In Springfield, Missouri, Timothy R. Davis
Soil Phosphorus Levels In Residential Lawns And Comparisons Among Four Land Uses In Springfield, Missouri, Timothy R. Davis
Graduate Theses/Dissertations
Eutrophication of surface waters due to high phosphorus (P) concentrations is an important water quality concern in Greene County, Missouri. Phosphorus enrichment has been linked to a variety of non-point sources including runoff from both agricultural and urban land uses. Soil P has been shown to be a source of P in runoff. The differences in soil P among different land uses may provide insight into which land use contributes more P in runoff. This study examines the soil composition, geochemistry and total P concentration of surface soil (0-5cm) in four land uses in Greene County, Missouri. The land uses …
Phytophthora Diseases Of Cutflower Crops, Department Of Agriculture And Food, Western Australia
Phytophthora Diseases Of Cutflower Crops, Department Of Agriculture And Food, Western Australia
Bulletins 4000 -
Phytophthora root rot is the most common soil borne disease causing plant death in native cut flower production. It is also a pathogen of exotic cutflower crops such as rose, lily, carnation, proteas and gerbera. The fungus, Phytophthora cinnamomi, the cause of jarrah dieback is the pathogen that first comes to mind when Phytophthora is mentioned. This has one of the widest host ranges of all Phytophthora species, particularly amongst native Australia species. P.nicotianae also has a wide host range, infecting a wide range of exotic, as well as Australian native flower crops. There are also a number of …
Glacial Deposits, Vol. 34, 2005-2006, Department Of Geography-Geology
Glacial Deposits, Vol. 34, 2005-2006, Department Of Geography-Geology
Glacial Deposits
Newsletter of the Department of Geography-Geology
Assessing The Potential Impact Of Microbes In The Edwards And Trinity Aquifers Of Central Texas, Kelli Willson Randall
Assessing The Potential Impact Of Microbes In The Edwards And Trinity Aquifers Of Central Texas, Kelli Willson Randall
LSU Master's Theses
The Edwards Aquifer in central Texas is one of the largest carbonate aquifers in the United States, supplying nearly two million people with water. The role of microorganisms in the development of deep carbonate aquifers has not been thoroughly investigated. The Edwards Aquifer is composed of a freshwater zone and a sulfidic, saline water zone. Down-well video surveys show an abundance of white filamentous and planktonic biomass floating in the water column, indicating that the saline water may serve as a habitat for microbes and provide a unique opportunity to investigate microbially enhanced deep subsurface karstification. A combination of geochemical …