On the use of double differences in inversion of surface movement measurements

Surface movement data can be used in data assimilation or inversion exercises to improve the level of knowledge of a compacting reservoir. We have designed, implemented and tested a new algorithm that uses measured optical height differences directly, without having to translate them to heights with regard to a geodetic reference level. This way...

Recent developments on the seismicity of the Groningen field in 2015

Bow-tie risk assessment combining causes and effects applied to gasoil storage in an abandoned salt cavern,

A semi-quantitative risk assessment is presented for the storage of gas oil in depleted salt caverns in the Twente region, the Netherlands. It is based on a bow-tie model, in which an incident, leakage of gas oil from the storage system (cavern and wells), is evaluated by assessing its possible causes and effects. The causes are all the events...

Geomechanics response and induced seismicity during gas field depletion in the Netherlands

In this paper we present a review ofcontrolling geological, tectonic and engineering factors lor induced seismic¡ty associated to gas depletion in the Netherlands and we place experiences from extensive Dutch geomechanical studies in the past decade in the contex[ ofgeneric models for induced seismicity. Netherlands is in a mature gas production...

Toetsing van de bodemdalingsprognoses en seismische hazard ten gevolge van gaswinning van het Groningen veld

Deterministische hazard analyse voor geïnduceerde seismiciteit in Nederland

In het kader van de Mijnbouwwet 2003 moeten seismische risicoanalyses in het winningsplan opgenomen worden. Bij olie- en gaswinning gaat het om geïnduceerde seismiciteit. In 2003 is door TNO en KNMI in opdracht van de mijnbouwmaatschappijen onderzoek uitgevoerd naar de seismische hazard door geïnduceerde aardbevingen. De resultaten van dit...

Joint history matching of well data and surface subsidence observations using the Ensemble Kalman Filter: A field study

The number of reported applications of the Ensemble Kalman Filter (EnKF) for history matching reservoir models is increasing steadily for various reasons. Here, we report on exploiting the capability of EnKF to handle observations from different sources simultaneously. While traditionally only well data are matched, we use surface subsidence...

Inversion of surface subsidence data to quantify reservoir compartmentalization: A field study

The Roswinkel gas field in the northeastern part of the Netherlands has been in production between 1980 and 2005. Located at about 2100 m depth, it is a severely faulted anticlinal structure, constituting up to 30 reservoir compartments. Due to the complicated nature of this field, there are large uncertainties in both the fault...

Inverting subsidence data to detect possible compartmentalization in a gas reservoir in The Netherlands

Subsidence can be induced by hydrocarbon production, due to the decrease in pore pressure in the reservoir which causes the reservoir to compact. The subsidence at any point on the surface is a result of the compaction over a large area of the reservoir. The properties of the reservoir and thus the compaction are uncertain. Therefore, an...

On the robustness of global radially anisotropic surface wave tomography

A number of recent global tomographic studies have modeled three dimensional variations in the parameters of radial anisotropy. As yet there is limited agreement among such studies, suggesting significant uncertainties in the models, which could lead to divergent geodynamical interpretations. In this study we assess the robustness of lateral...

On the effect of horizontal deformation on insar subsidence estimates

Reply to comment by S. Crampin on 'global anisotropic phase velocity maps for higher mode Love and Rayleigh waves'

We thank Stuart Crampin for his interest in our recent paper but respectfully disagree when he argues that our measurements are not appropriate for inferring mantle anisotropy. The approximations we made are common and perfectly acceptable for the considered frequency band. The comment ignores a large part of the literature which investigated...

Reply to comment by A. Tommasi and D. Mainprice on Visser et al. (2008), "Probability of radial anisotropy in the deep mantle" [Earth Planet Sci. Lett. 270 (2008) 241-250]

GTP binding activity of membrane proteins in isolated barley embryo is enhanced by abscisic acid

Effects of dormancy-breaking chemicals on ABA levels in barley grain embryos

The endogenous ABA contents of dormant and nondormant barley grains were determined following application of different compounds to break dormancy. The chemicals used for breaking of dormancy in intact dormant grains were weak and strong acids, alcohols,. hydrogen peroxide, cyanide, nitrate, salicylic acid, gibberellic acid and fusicoccin. The...

Molecular cloning and characterization of an inorganic pyrophosphatase from barley

Effects of modulation of calcium levels and calcium fluxes on ABA- induced gene expression in barley aleurone

We present data to elucidate the involvement of calcium ions in abscisic acid (ABA)-induced gene expression. Modulation of external calcium concentrations was able to affect ABA-induced specific RAB gene expression. At a constant ABA level with increasing extracellular calcium level, an increasing RAB mRNA expression was measured. In barley...

Rapid germination of a barley mutant is correlated with a rapid turnover of abscisic acid outside the embryo