Fault Seal Analysis for CO2 Storage: Fault Zone Architecture, Fault Permeability, and Fluid Migration Pathways in Exposed Analogs in Southeastern Utah

Geologic storage of anthropogenic carbon dioxide (CO2) by injection into underground porous sandstone reservoirs has been proposed as a method for the reduction of anthropogenic greenhouse gas emissions. Upwards migration and leakage of injected fluids along natural fault and fracture networks is a key risk factor for potential injection locations. We examine exposed natural analogs to evaluate the impacts of faulting and fracturing on reservoir and top-seal pairs and to evaluate evidence for paleomigration of fluids along the fault zone. We examine the Iron Wash fault, a 25-km long normal fault which cuts Jurassic sedimentary rocks and has throws that range from 20-120 m, to examine how a fault may affect seal integrity. Field mapping, kinematic analysis, petrographic analysis, characterization of the fault zone facies and fault architecture, analysis of altered and mineralized rocks in and around the fault zone, and modeling of fault seal capacity was conducted to provide an understanding of the Iron Wash fault zone. Field data and observations were combined with well log and borehole data to produce three types of models for the Iron Wash fault: 1) geometric model of the fault in the subsurface, 2) predictive models of fault zone behavior and fault seal analysis, and 3) predictive geomechanical models of the response of the fault zone to an imposed stress field and increasing the effective stress on the fault. We conclude that the Iron Wash fault zone has low sealing capacity and will likely not behave as a seal for fluids against the fault zone due primarily to modest throw on the fault and high frequency of fractures associated with the fault zone. Analysis of fluid alteration and mineralization around the fault zone indicates that the fault zone was conduit for paleo-fluids. We conclude that the fault is not likely to develop a sealing membrane and therefore will most likely fail as a seal to fluids moving through the reservoirs modeled here. Modeling results indicate that a reduction in the effective normal stress on fault surfaces may induce failure of faults resulting in earthquakes or increased hydraulic conductivity of fractures

Chondroitin Sulfate Proteoglycans Are a Common Component of Neuronal Inclusions and Astrocytic Reaction in Neurodegenerative Diseases

Previously, we showed three differentially sulfated forms of chondroitin sulfate proteoglycans (CSPG) associated with senile plaques, astrocytes and neurofibrillary tangles in Alzheimer\u27s disease. Here, monoclonal antibodies were used to demonstrate CSPGs in other neurodegenerative diseases. CSPGs were found associated with inclusions of Parkinson\u27s, diffuse Lewy body, Pick\u27s diseases, and progressive supranuclear palsy. Reacting astrocytes in each of these neurodegenrative diseases and Huntington\u27s disease showed immunoreactivity for CSPG. CSPG distribution in a variety of neurodegenerative diseases suggests that similar mechanisms may be involved in the accumulation of proteoglycans in a number of filamentous inclusions

Merging late Holocene molecular organic and foraminiferal-based geochemical records of sea surface temperature in the Gulf of Mexico

Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 26 (2011): PA1209, doi:10.1029/2010PA002000.A molecular organic geochemical proxy (TEX86) for sea surface temperature (SST) is compared with a foraminifera-based SST proxy (Mg/Ca) in a decadal-resolution marine sedimentary record spanning the last 1000 years from the Gulf of Mexico. We assess the relative strengths of the organic and inorganic paleoceanographic techniques for reconstructing high-resolution SST variability during recent climate events, including the Little Ice Age (LIA) and the Medieval Warm Period (MWP). SST estimates based on the molecular organic proxy TEX86 show a similar magnitude and pattern of SST variability to foraminiferal Mg/Ca-SST estimates but with some important differences. For instance, both proxies show a cooling (1°C–2°C) of Gulf of Mexico SSTs during the LIA. During the MWP, however, Mg/Ca-SSTs are similar to near-modern SSTs, while TEX86 indicates SSTs that were cooler than modern. Using the respective SST calibrations for each proxy results in TEX86-SST estimates that are 2°C–4°C warmer than Mg/Ca-SST throughout the 1000 year record. We interpret the TEX86-SST as a summer-weighted SST signal from the upper mixed layer, whereas the Mg/Ca-SST better reflects the mean annual SST. Downcore differences in the SST estimates between the two proxies (ΔT = TEX86 − Mg/Ca) are interpreted in the context of varying seasonality and/or changing water column temperature gradients.This work was supported, in part, by the National Science Foundation under grants OCE‐0318361 and OCE‐0903017

Commodifying development experience: deconstructing development as gift in the development blockbuster

This paper discusses the recent rise of popular ‘blockbuster’ books written by international development industry insiders and produced by commercial publishers. The paper explores a set of common stylistic devices found within this emerging genre. Though each book is different, a key trope is the story of an author's earlier professional life—the hard lessons and gritty insights that have supposedly emerged from it—that normally underpins each narrative. By living the challenges involved in development work at first hand, and by making mistakes and experiencing epiphanies along the way, these author-professionals want readers to know that they have found out the hard way that long-cherished beliefs about development now need to be questioned. Readers are invited to relive these lessons and epiphanies, and to think and act differently about development by upholding a highly pragmatic form of development professionalism. Combining elements of research monograph, self-help book and personal memoir, these development blockbuster books can be understood not only as commodities, but also as part of the development gift. The authors promise a gift of experience but, in reality, these books are mundane commodities enmeshed in capitalist exchange relations

Population policies and education: exploring the contradictions of neo-liberal globalisation

The world is increasingly characterised by profound income, health and social inequalities (Appadurai, 2000). In recent decades development initiatives aimed at reducing these inequalities have been situated in a context of increasing globalisation with a dominant neo-liberal economic orthodoxy. This paper argues that neo-liberal globalisation contains inherent contradictions regarding choice and uniformity. This is illustrated in this paper through an exploration of the impact of neo-liberal globalisation on population policies and programmes. The dominant neo-liberal economic ideology that has influenced development over the last few decades has often led to alternative global visions being overlooked. Many current population and development debates are characterised by polarised arguments with strongly opposing aims and views. This raises the challenge of finding alternatives situated in more middle ground that both identify and promote the socially positive elements of neo-liberalism and state intervention, but also to limit their worst excesses within the population field and more broadly. This paper concludes with a discussion outling the positive nature of middle ground and other possible alternatives

T Cell Activation and Senescence Predict Subclinical Carotid Artery Disease in HIV-Infected Women

Background. Individuals infected with human immunodeficiency virus (HIV) have increased risk of cardiovascular events. It is unknown whether T cell activation and senescence, 2 immunologic sequelae of HIV infection, are associated with vascular disease among HIV-infected adults

Skunk River Review September 1989, vol 1 no 1

https://openspace.dmacc.edu/skunkriver/1004/thumbnail.jp

Impact of Differential Attrition on the Association of Education With Cognitive Change Over 20 Years of Follow-up: The ARIC Neurocognitive Study

Studies of long-term cognitive change should account for the potential effects of education on the outcome, since some studies have demonstrated an association of education with dementia risk. Evaluating cognitive change is more ideal than evaluating cognitive performance at a single time point, because it should be less susceptible to confounding. In this analysis of 14,020 persons from a US cohort study, the Atherosclerosis Risk in Communities (ARIC) Study, we measured change in performance on 3 cognitive tests over a 20-year period, from ages 48–67 years (1990–1992) through ages 70–89 years (2011–2013). Generalized estimating equations were used to evaluate the association between education and cognitive change in unweighted adjusted models, in models incorporating inverse probability of attrition weighting, and in models using cognitive scores imputed from the Telephone Interview for Cognitive Status for participants not examined in person. Education did not have a strong relationship with change in cognitive test performance, although the rate of decline was somewhat slower among persons with lower levels of education. Methods used to account for selective dropout only marginally changed these observed associations. Future studies of risk factors for cognitive impairment should focus on cognitive change, when possible, to allow for reduction of confounding by social or cultural factors

Admixture Mapping Scans Identify a Locus Affecting Retinal Vascular Caliber in Hypertensive African Americans: the Atherosclerosis Risk in Communities (ARIC) Study

Retinal vascular caliber provides information about the structure and health of the microvascular system and is associated with cardiovascular and cerebrovascular diseases. Compared to European Americans, African Americans tend to have wider retinal arteriolar and venular caliber, even after controlling for cardiovascular risk factors. This has suggested the hypothesis that differences in genetic background may contribute to racial/ethnic differences in retinal vascular caliber. Using 1,365 ancestry-informative SNPs, we estimated the percentage of African ancestry (PAA) and conducted genome-wide admixture mapping scans in 1,737 African Americans from the Atherosclerosis Risk in Communities (ARIC) study. Central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) representing summary measures of retinal arteriolar and venular caliber, respectively, were measured from retinal photographs. PAA was significantly correlated with CRVE (ρ = 0.071, P = 0.003), but not CRAE (ρ = 0.032, P = 0.182). Using admixture mapping, we did not detect significant admixture association with either CRAE (genome-wide score = −0.73) or CRVE (genome-wide score = −0.69). An a priori subgroup analysis among hypertensive individuals detected a genome-wide significant association of CRVE with greater African ancestry at chromosome 6p21.1 (genome-wide score = 2.31, locus-specific LOD = 5.47). Each additional copy of an African ancestral allele at the 6p21.1 peak was associated with an average increase in CRVE of 6.14 µm in the hypertensives, but had no significant effects in the non-hypertensives (P for heterogeneity <0.001). Further mapping in the 6p21.1 region may uncover novel genetic variants affecting retinal vascular caliber and further insights into the interaction between genetic effects of the microvascular system and hypertension