Ground motion in areas of abandoned mining: application of the intermittent SBAS (ISBAS) to the Northumberland and Durham coalfield, UK

In this paper, we investigate land motion and groundwater level change phenomena using differential interferometric synthetic aperture radar (DInSAR) over the Northumberland and Durham coalfield in the United Kingdom. The study re-visits earlier research that applied a persistent scatterers interferometry (PSI) technique to ERS (European Remote Sensing) and ENVISAT (Environmental Satellite) data. Here, the Intermittent Small Baseline Subset (ISBAS) DInSAR technique is applied to ERS, ENVISAT and Sentinel-1 SAR datasets covering the late 1990s, the 2000s and the mid-2010s, respectively to increase spatial coverage, aid the geological interpretation and consider the latest Sentinel-1 data. The ERS data identify surface depressions in proximity to former collieries, while all three data sets ascertain broad areas are experiencing regional scale uplift, often occurring in previously mined areas. Uplift is attributed to increases in pore pressure in the overburden following the cessation of groundwater pumping after mine closure. Rising groundwater levels are found to correlate to ground motion measurements at selected monitoring sites, most notably in the surrounding area of Ashington. The area is divided by an impermeable EW fault; to the south, surface heave was identified as groundwater levels rose in the 1990s, whereas to the north, this phenomenon occurred two decades later in the 2010s. The data emphasize the complexity of the post-mining surface and subsurface environment and highlight the benefit that InSAR, utlizing the ISBAS technique, can provide in its charaterization

Integration of VICbus, FDL, SCI and Ethernet in the CERN CASCADE data acquisition system

Cascade is a multi-processor real-time data-acquisition system for HEP experiments developed at CERN by the ECP-DS group. Configurations supported today include VMEbus processors running OS-9 and UNIX workstations. The CASCADE data acquisition processes, called stages communicate via links, at present VICbus between VME crates and Ethernet between VMEbus processors and workstations. Work is in progress to introduce new inter-stage links based on the Fast Data Link between VME crates and on SCI for data exchange between SUN stations. The paper gives a short description of the architecture of CASCADE with emphasis on the link aspects. The implementation and current status of the inter-stage links based on VICbus, Ethernet, FDI, and SCI will be described and results on the performances presented

Non-Western small states:activists or survivors?

In this introduction to the collection, we explain its focus on non-Western small states. While the terms ‘non-Western’ and ‘small states’ are problematic – we discuss these problems here – the smallness and non-Westerness of the states studied by the contributing authors set them apart in a way that has attracted little academic attention so far. They allow them to operate with fewer normative and practical constraints than their bigger, Western counterparts; offer them a wide range of (often historically forged) political ties; and force them to draw on a diversity of approaches and strategic thinking, and a creativity, that they are too rarely credited for. Non-Western small states, rather than being mere survivors constrained to the world’s periphery, are better understood as activist states intent on existing. The collection offers a range of analytical keys to make sense of these states and their role in the international scene

A noninvasive method for measuring the velocity of diffuse hydrothermal flow by tracking moving refractive index anomalies

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95358/1/ggge1802.pd

Pore Pressure Evolution and Fluid Flow During Visco-Elastic Single-Layer Buckle Folding

Pore pressure and fluid flow during the deformational history of geologic structures are directly influenced by tectonic deformation events. In this contribution, 2D plane strain finite element analysis is used to study the influence of different permeability distributions on the pore pressure field and associated flow regimes during the evolution of visco-elastic single-layer buckle folds. The buckling-induced fluid flow regimes indicate that flow directions and, to a lesser degree, their magnitudes vary significantly throughout the deformation and as a function of the stratigraphic permeability distribution. The modelling results suggest that the volumetric strain and the permeability distribution significantly affect the resulting flow regime at different stages of fold development. For homogeneous permeability models (k \u3e 10-21 m2), low strain results in a mostly pervasive fluid flow regime and is in agreement with previous studies. For larger strain conditions, fluid focusing occurs in the buckling layer towards the top of the fold hinge. For low permeabilities (\u3c10-21 m2), local focused flow regimes inside the buckling layer emerge throughout the deformation history. For models featuring a low-permeability layer embedded in a high-permeability matrix or sandwiched between high-permeability layers, focused flow regimes inside the folded layer result throughout the deformation history, but with significant differences in the flow vectors of the surrounding layers. Fluid flow vectors induced by the fold can result in different, even reversed, directions depending on the amount of strain. In summary, fluid flow regimes during single-layer buckling can change from pervasive to focused and fluid flow vectors can be opposite at different strain levels, that is the flow vectors change significantly through time. Thus, a complete understanding of fluid flow regimes associated with single-layer buckle folds requires consideration of the complete deformation history of the fold

Bottom pressure signals at the TAG deep-sea hydrothermal field : evidence for short-period, flow-induced ground deformation

Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 36 (2009): L19301, doi:10.1029/2009GL040006.Bottom pressure measurements acquired from the TAG hydrothermal field on the Mid-Atlantic Ridge (26°N) contain clusters of narrowband spectral peaks centered at periods from 22 to 53.2 minutes. The strongest signal at 53.2 min corresponds to 13 mm of water depth variation. Smaller, but statistically significant, signals were also observed at periods of 22, 26.5, 33.4, and 37.7 min (1–4 mm amplitude). These kinds of signals have not previously been observed in the ocean, and they appear to represent vertical motion of the seafloor in response to hydrothermal flow - similar in many ways to periodic terrestrial geysers. We demonstrate that displacements of 13 mm can be produced by relatively small flow-induced pressures (several kPa) if the source region is less than ∼100 m below the seafloor. We suggest that the periodic nature of the signals results from a non-linear relationship between fluid pore pressure and crustal permeability

Inhibition of adenosine monophosphate-activated protein kinase-3-hydroxy-3-methylglutaryl coenzyme a reductase signaling leads to hypercholesterolemia and promotes hepatic steatosis and insulin resistance

Adenosine monophosphate–activated protein kinase (AMPK) regulates multiple signaling pathways involved in glucose and lipid metabolism in response to changes in hormonal and nutrient status. Cell culture studies have shown that AMPK phosphorylation and inhibition of the rate‐limiting enzyme in the mevalonate pathway 3‐hydroxy‐3‐methylglutaryl (HMG) coenzyme A (CoA) reductase (HMGCR) at serine‐871 (Ser871; human HMGCR Ser872) suppresses cholesterol synthesis. In order to evaluate the role of AMPK‐HMGCR signaling in vivo, we generated mice with a Ser871‐alanine (Ala) knock‐in mutation (HMGCR KI). Cholesterol synthesis was significantly suppressed in wild‐type (WT) but not in HMGCR KI hepatocytes in response to AMPK activators. Liver cholesterol synthesis and cholesterol levels were significantly up‐regulated in HMGCR KI mice. When fed a high‐carbohydrate diet, HMGCR KI mice had enhanced triglyceride synthesis and liver steatosis, resulting in impaired glucose homeostasis. Conclusion: AMPK‐HMGCR signaling alone is sufficient to regulate both cholesterol and triglyceride synthesis under conditions of a high‐carbohydrate diet. Our findings highlight the tight coupling between the mevalonate and fatty acid synthesis pathways as well as revealing a role of AMPK in suppressing the deleterious effects of a high‐carbohydrate diet

Prediction of permeability and formation factor of sandstone with hybrid lattice Boltzmann/finite element simulation on microtomographic images

In Fontainebleau sandstone, the evolution of transport properties with porosity is related to changes in both the size and connectivity of the pore space. Microcomputed tomography can be used to characterize the relevant geometric attributes, with the resolution that is sufficiently refined for realistic simulation of transport properties based on the 3D image. In this study, we adopted a hybrid computation scheme that is based on a hierarchical multi-scale approach. The specimen was partitioned into cubic sub-volumes for pore-scale simulation of hydraulic permeability and formation factor using the lattice Boltzmann method. The pore-scale results were then linked with finite element simulation in a homogenized scheme to compute and upscale the transport properties to specimen scale. The simulated permeability and formation factor have magnitude and anisotropy that are in good agreement with experimental rock physics data. Together with simulated and measured values of connected porosity and specific surface area, they provide useful insights into how pore geometry controls the evolution of the transport properties