83 research outputs found
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Comparative Anatomy and Petrophysical Property Structure of Seaward- and Landward- Stepping Deltaic Reservoir Analogs, Ferron Sandstone, Utah
The recovery of natural gas from fluvial-deltaic reservoirs is governed by complex internal architectures. To aid in the translation of outcrop geology to reservoir equivalents, all existing Ferron outcrop, petrophysical, and subsurface data have been integrated into a geologic model of reservoir heterogeneity that compares and contrasts seaward- and landward-stepping stratigraphic cycles. Reservoir architecture varies in a predictable fashion between seaward- and landward-stepping stratigraphic cycles. Within seaward-stepping units, delta-front strata are highly compartmentalized by marine and marginal marine shales coincident with stratigraphic cycle, parasequence, and mouth-bar bounding surfaces. Coeval distributaries are volumetrically a minor component and are preserved as ribbon-like sand bodies encased in finer-grained strata. By contrast, within landward-stepping units, parasequences and component mouth-bar deposits are amalgamated into a lithologically homogeneous strike-elongate sand body. Coeval distributaries are volumetrically a major component and are preserved as a complex network of interconnected, lithologically diverse sand bodies. Internal heterogeneities, related to floodplain, abandoned channel fill, and mud-clast lag deposits, severely disrupt lateral and vertical continuity. Analysis of the Ferron gas field reveals that favorable sites for stratigraphic entrapment occur where proximal and distal portions of parasequences pinch out into lagoonal and marine mudstones, respectively.Bureau of Economic Geolog
MyD88-dependent signaling influences fibrosis and alternative macrophage activation during Staphylococcus aureus biofilm infection.
Bacterial biofilms represent a significant therapeutic challenge based on their ability to evade host immune and antibiotic-mediated clearance. Recent studies have implicated IL-1β in biofilm containment, whereas Toll-like receptors (TLRs) had no effect. This is intriguing, since both the IL-1 receptor (IL-1R) and most TLRs impinge on MyD88-dependent signaling pathways, yet the role of this key adaptor in modulating the host response to biofilm growth is unknown. Therefore, we examined the course of S. aureus catheter-associated biofilm infection in MyD88 knockout (KO) mice. MyD88 KO animals displayed significantly increased bacterial burdens on catheters and surrounding tissues during early infection, which coincided with enhanced dissemination to the heart and kidney compared to wild type (WT) mice. The expression of several proinflammatory mediators, including IL-6, IFN-γ, and CXCL1 was significantly reduced in MyD88 KO mice, primarily at the later stages of infection. Interestingly, immunofluorescence staining of biofilm-infected tissues revealed increased fibrosis in MyD88 KO mice concomitant with enhanced recruitment of alternatively activated M2 macrophages. Taken in the context of previous studies with IL-1β, TLR2, and TLR9 KO mice, the current report reveals that MyD88 signaling is a major effector pathway regulating fibrosis and macrophage polarization during biofilm formation. Together these findings represent a novel example of the divergence between TLR and MyD88 action in the context of S. aureus biofilm infection
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Chararcterization of Heterogeneity Style and Permeability Structure in Fluvial Reservoirs
The Cretaceous Acu Formation was investigated as an analog to a heterogeneous group of reservoirs having significant potential for reserve growth in the Potiguar Basin of Brazil. Architectural, lithologic, and petrophysical information was collected from an outcrop exposing a fluvially deposited sandstone body located in the state of Rio Grande do Norte, Brazil. Sedimentologic descriptions of the sandstone body were collected from a series of vertical transects spaced evenly across the outcrop. Stratal surfaces traced between transects were recorded on photomosaics. Measurements of permeability were obtained from each transect by use of a portable probe-style mechanical field permeameter. A cross-section depicting bedding architecture, sedimentologic attributes, and permeability values was constructed, and the information incorporated into a two-dimensional representation of reservoir architecture using Stratamodel's Stratigraphic Geocellular Modeling software (SGM). The SGM technique deterministically interpolates permeability data between transect locations using a lithologic or stratigraphic framework.Bureau of Economic Geolog
The Kuznets Curve and the Inequality Process
Four economists, Mauro Gallegati, Steven Keen, Thomas Lux, and Paul Ormerod, published a paper after the 2005 Econophysics Colloquium criticizing conservative particle systems as models of income and wealth distribution. Their critique made science news: coverage in a feature article in Nature. A particle system model of income distribution is a hypothesized universal statistical law of income distribution. Gallegati et al. (2006) claim that the Kuznets Curve shows that a universal statistical law of income distribution is unlikely and that a conservative particle system is inadequate to account for income distribution dynamics. The Kuznets Curve is the graph of income inequality (ordinate variable) against the movement of workers from rural subsistence agriculture into more modern sectors of the economy (abscissa). The Gini concentration ratio is the preferred measure of income inequality in economics. The Kuznets Curve has an initial uptick from the Gini concentration ratio of the earned income of a poorly educated agrarian labor force. Then the curve falls in near linear fashion toward the Gini concentration ratio of the earned incomes of a modern, educated labor force as the modern labor force grows. The Kuznets Curve is concave down and skewed to the right. This paper shows that the iconic Kuznets Curve can be derived from the Inequality Process (IP), a conservative particle system, presenting a counter-example to Gallegati et al.’s claim. The IP reproduces the Kuznets Curve as the Gini ratio of a mixture of two IP stationary distributions, one characteristic of the wage income distribution of poorly educated workers in rural areas, the other of workers with an education adequate for industrial work, as the mixing weight of the latter increases and that of the former decreases. The greater purchasing power of money in rural areas is taken into account
Creative Education
Effective online collaboration is a valuable instructional approach appropriate for 21st century teaching and learning. This paper describes a case that involves two higher education student cohorts from the United States and Australia engaged in a global collaboration to promote an authentic teaching and learning experience. The collaboration aims to involve students in sharing, reflecting and synthesizing new knowledge to make a comparative analysis between education systems from the two countries. The global collaboration is matched against an Assessment and Teaching of 21st Century Skills framework to comprehend and justify this approach as part of a teacher education course. This case advocates the value of having future teachers using online resources in a global context as a way to effectively integrate new content with various technology resources to develop new learning and new relationships beyond their own culture
Potential Sand and Gravel Resources of the Canton 30 x 60-Minute Quadrangle, Ohio
The Ohio Department of Natural Resources (ODNR), Division of Geological Survey has completed a reconnaissance map showing areas of mineable sand and gravel resources in the Canton, Ohio, 30 x 60-minute 1:100,000-scale quadrangle. The main purpose of this map was to create a reconnaissance-level map that would show the potential for mining sand-and-gravel in this quadrangle. The map shows areas of surficial materials in increments of 10 feet and then differentiates sand, sand and gravel, and ice-contact deposits from finer grained materials, such as glacial till, lacustrine clay and silt, and alluvial materials. The sand and sand-and-gravel units include both surficial and buried outwash and valley train deposits and ice-contact deposits, such as kames, kame terraces, and eskers. This map was created to show the total thickness or accumulation of sand and gravel in the Canton 30 x 60-minute quadrangle. The thickness of sand-and-gravel deposits helps determine if it is economically viable.United States Geological Survey: National Cooperative Geologic Mapping Program, Great Lakes Geologic Mapping Coalitio
Suitablility for Solid-Waste Disposal in the Lorain 30 x 60-Minute Quadrangle
The Ohio Department of Natural Resources (ODNR), Division of Geological Survey has completed a reconnaissance map showing areas suitable for solid waste disposal in the Lorain, Ohio, 30 x 50-minute (1:1,100,000-scale) quadrangle. The main purpose of this map is to provide a reconnaissance level map that shows the relative suitability of various surficial materials for the disposal or containment of solid waste in this quadrangle. Our goal was to create this map from existing ODNR Division of Geological Survey maps and GIS datasets as much as possible. Consequently, the Lorain map is a derivative map based directly from the ODNR Division of Geological Survey SG-2 Series map, Surficial Geology of the Lorain and Put-in-Bay 30 x 60 Minute Quadrangles (Pavey and others, 2005). The SG-2 series features maps based upon polygons that represent a “stack” of mapped unit lithologies and thicknesses. These maps show surficial materials in increments of 10 feet within each polygon across the study area. A set of queries were run in ESRI ArcGIS to determine the range of thickness and nature of the sediments.
The main premise of this map is to specify areas of thick, fine-grained glacial till and glaciolacustrine silt and clay deposits for solid-waste disposal and containment. A minimum of 30 feet of fine-grained material was deemed necessary for waste disposal for areas where the drift overlies shale; siltstone; or interbedded, shaley limestone. If the fine-grained material was directly overlying an aquifer, the minimum required thickness was increased to 50 feet. Aquifers included sand and gravel, sandstone, limestone, and dolomite. Areas with over 20 feet of sand and gravel or sand at the surface (e.g., kames, beach ridges) were excluded as were areas with alluvium (active streams) and organic deposits at the land surface. The main factor in the decision-making process was to have adequate fine-grained materials overlying the aquifers.United States Geological Survey, National Cooperative Geologic Mapping Program, Great Lakes Geologic Mapping Coalitio
Potential for Mineable Bedrock in the Findlay 30 x 60 minute quadrangle
The Ohio Department of Natural Resources (ODNR), Division of Geological Survey has completed a reconnaissance map showing areas of mineable bedrock, including shale, limestone, and dolomite, likely covered by thin surficial materials (glacial drift) in the Findlay, Ohio, 30 x 50-minute (1:1,100,000-scale) quadrangle. The main purpose of this map was to create a reconnaissance-level map that shows the potential for mining carbonate and shale bedrock in this quadrangle. We sought to create this map from as many existing ODNR Division of Geological Survey maps and GIS datasets as possible. The map shows areas of surficial materials in increments of 10 ft and totaling less than 40 ft overlying Silurian- and Devonian-age dolomite and limestone, and it also shows a limited area in the southeastern most portion of the quadrangle where surficial materials (totaling less than 20 ft) overlay potential Devonian-age shale resources.United States Geological Survey: National Cooperative Geologic Mapping Program, Great Lakes Geologic Mapping Coalitio
Potential for Mineable Bedrock in the Marion 30 X 60 minute quadrangle
The Ohio Department of Natural Resources (ODNR), Division of Geological Survey has completed a reconnaissance map showing areas of mineable bedrock, including shale, limestone, and dolomite, likely covered by thin surficial materials (glacial drift) in the Marion, Ohio, 30 x 50-minute (1:1,100,000-scale) quadrangle. The main purpose of this map was to create a reconnaissance-level map that shows the potential for mining carbonate and shale bedrock in this quadrangle. We sought to create this map from as many existing ODNR Division of Geological Survey maps and GIS datasets as possible. The map shows areas of surficial materials in increments of 10 ft and totaling less than 40 ft overlying Silurian- and Devonian-age dolomite and limestone, and it also shows a limited area in the easternmost portion of the quadrangle where surficial materials (totaling less than 20 ft) overlay potential Devonian-age shale resources.United States Geological Survey: National Cooperative Geologic Mapping Program, Great Lakes Geologic Mapping Coalitio
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