Formation of a sealing well barrier by the creep of rock salt: Numerical investigations

Rock salt formations are a common reservoir seal worldwide with excellent sealing capacity. Restoring the sealing capacity of rock salt caprocks penetrated by wells using the same rock salt as plugging material is therefore an attractive, safe and environmentally friendly option. The concept is based on the removal of a section of casing over a...

Well integrity of high temperature wells: Effect of mineralogical changes on mechanical properties of well cement

Wells used for steam-assisted gravity drainage (SAGD), for cyclic steam stimulation (CSS), for hydrocarbon production in areas with anomalous high geothermal gradient, or for geothermal energy extraction all are operated in high temperature environments where maintaining long term wellbore integrity is one of the key challenges. Changes in...

Numerical investigations of cement interface debonding for assessing well integrity risks

Loading history during drilling, completion and operations of the well can affect wellbore integrity. Debonding along well cement interfaces leads to the creation of micro-annuli and potential leakage pathways. We investigate the risk of debonding by modeling the integrity of an example well throughout its life-time using a finite element...

On the use of influence functions for subsidence evaluation

Fast models to estimate subsidence resulting from subsurface extraction processes usually employ a nucleus-of-strain solution based on a center of compression. The solution for such a strain nucleus is then employed as an influence function. This approach is based on the superposition principle that applies for linear elasticity of the...

The geomechanical response of naturally fractured carbonate reservoirs to operation of a geothermal doublet

The properties of faults and fractures under dynamic reservoir conditions are critical in determining flow and performance of geothermal doublets in fractured reservoirs. The complexity of faults obtained from geological and seismic characterization is usually not honored in flow models for fractured reservoirs. Fault zone architectures may...

The impact of viscoelastic caprock on fault reactivation and fault rupture in producing gas fields

Discrete element modelling of wellbore integrity in high temperature geothermal reservoirs

Geothermal drilling environments are often hostile to well materials, especially in magmatic settings where properties of well casing and cements may rapidly change as a result of high temperatures and chemically active formation fluids. Prolonging the lifetime of such geothermal wells is one of the key challenges to achieve a commercially...

Geomechanical responses induced by large-scale CO2 injection in a multilayer saline aquifer in Kuwait

Large-scale CO2 injection in saline aquifers will cause pressure build-up in brine far beyond the extent of CO2 plume. In this paper, we evaluate the geomechanical responses of large-scale CO2 storage in the multilayer aquifer of the Kra Al-Maru Trend in Kuwait. The site was selected after screening the whole territory of Kuwait, identifying and...

Geomechanical response to N2 injection as a means of pressure maintenance in a sandstone reservoir

Pressure maintenance by injection of nitrogen into a reservoir is one of the potential options to mitigate induced seismicity during gas production. It is expected that seismicity and the seismic hazard can be reduced by decreasing the stress changes and compaction associated with the declining pore pressure in the reservoir rocks. However,...

Performance of acoustic communications for AUVs operating in the North Sea

Translating laboratory compaction test results to field scale

In recent studies on the surface subsidence caused by hydrocarbon recovery of the Groningen gas field, the predicted subsidence is overestimated if results of compaction experiments are not corrected by an empirical `upscaling factor'. In order to find an explanation for this `upscaling factor', an analysis is presented of different laboratory...

Subsidence due to gas production in the Wadden Sea: How to ensure no harm will be done to nature

The Wadden Sea is a shallow tidal sea in the north of the Netherlands where gas production is ongoing since 1986. Due to the sensitive nature of this area, gas extraction induced subsidence must remain within the "effective subsidence capacity" for the two tidal basins (Pinkegat and Zoutkamperlaag) affected. We present a probabilistic method to...

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...

Estimating the distribution of salt cavern squeeze using subsidence measurements

We report a field study on solution mining of magnesium chloride from bischofite layers in the Netherlands at depths between 1500 and 1850 m. Subsidence that was observed in the area is due to part of the brine production being realized by cavern squeeze; some of which were connccted. Wc used an earlier developed inversion scheme to quantify the...

Upfront predictions of hydraulic fracturing and gas production in underexplored shale gas basins: Example of the posidonia shale formation in the Netherlands

Upfront predictions of hydraulic fracturing and gas production of potential shale gas targets in Europe are important as often large potential resources are deduced without detailed knowledge on the potential for successful stimulation. Such predictions are challenging as they need to be based on limited available data, i.e. without well tests...

Evaluation of three Italian tuffs (Neapolitan Yellow Tuf, Tufo Romano and Tufo Etrusco) as compatible replacement stone for Römer tuff in Dutch built cultural heritage

Rhenish tuffs from the volcanic Eifel region in Germany, in particular the so-called Römer tuff, are among the most prominent and voluminous natural stones in Dutch monuments. The Römer tuff has been used since Roman times, and was widely used again in Romanesque (and to a lesser extent Romano-Gothic and early Gothic) architecture. The limited ...