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Browsing by Author "Kruiver, Pauline P."

Now showing 1 - 8 of 8
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    Capturing spatial variability in the regional Ground Motion Model of Groningen, the Netherlands
    Kruiver, Pauline P.; Pefkos, Manos; Rodriguez-Marek, Adrian; Campman, Xander; Ooms-Asshoff, Kira; Lavoue, Anais; Stafford, Peter J.; van Elk, Jan; Chmiel, Malgorzata (Cambridge University Press, 2022-08-17)
    Long-term exploration of the Groningen gas field in the Netherlands led to induced seismicity. Over the past nine years, an increasingly sophisticated Ground Motion Model (GMM) has been developed to assess the site response and the related seismic hazard. The GMM output strongly depends on the shear-wave velocity (V ( S )), among other input parameters. To date, V ( S ) model data from soil profiles (Kruiver et al., Bulletin of Earthquake Engineering, 15(9): 3555-3580, 2017; Netherlands Journal of Geosciences, 96(5): s215-s233, 2017) have been used in the GMM. Recently, new V ( S ) profiles above the Groningen gas field were constructed using ambient noise surface wave tomography. These so-called field V ( S ) data, even though spatially limited, provide an independent source of V ( S ) to check whether the level of spatial variability in the GMM is sufficient. Here, we compared amplification factors (AF) for two sites (Borgsweer and Loppersum) calculated with the model V ( S ) and the field V ( S ) (Chmiel et al., Geophysical Journal International, 218(3), 1781-1795, 2019 and new data). Our AF results over periods relevant for seismic risk (0.01-1.0 s) show that model and field V ( S ) profiles agree within the uncertainty range generally accepted in geo-engineering. In addition, we compared modelled spectral accelerations using either field V ( S ) or model V ( S ) in Loppersum to the recordings of an earthquake that occurred during the monitoring period (M-L 3.4 Zeerijp on 8 January 2018). The modelled spectral accelerations at the surface for both field V ( S ) and model V ( S ) are coherent with the earthquake data for the resonance periods representative of most buildings in Groningen (T = 0.2 and 0.3 s). These results confirm that the currently used V ( S ) model in the GMM captures spatial variability in the site response and represents reliable input for the site response calculations.
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    Characterisation of ground motion recording stations in the Groningen gas field
    Noorlandt, Rik; Kruiver, Pauline P.; de Kleine, Marco P. E.; Karaoulis, Marios; de Lange, Ger; Di Matteo, Antonio; von Ketelhodt, Julius; Ruigrok, Elmer; Edwards, Benjamin; Rodriguez-Marek, Adrian; Bommer, Julian J.; van Elk, Jan; Doornhof, Dirk (2018-05)
    The seismic hazard and risk analysis for the onshore Groningen gas field requires information about local soil properties, in particular shear-wave velocity (V (S)). A fieldwork campaign was conducted at 18 surface accelerograph stations of the monitoring network. The subsurface in the region consists of unconsolidated sediments and is heterogeneous in composition and properties. A range of different methods was applied to acquire in situ V (S) values to a target depth of at least 30 m. The techniques include seismic cone penetration tests (SCPT) with varying source offsets, multichannel analysis of surface waves (MASW) on Rayleigh waves with different processing approaches, microtremor array, cross-hole tomography and suspension P-S logging. The offset SCPT, cross-hole tomography and common midpoint cross-correlation (CMPcc) processing of MASW data all revealed lateral variations on length scales of several to tens of metres in this geological setting. SCPTs resulted in very detailed V (S) profiles with depth, but represent point measurements in a heterogeneous environment. The MASW results represent V (S) information on a larger spatial scale and smooth some of the heterogeneity encountered at the sites. The combination of MASW and SCPT proved to be a powerful and cost-effective approach in determining representative V (S) profiles at the accelerograph station sites. The measured V (S) profiles correspond well with the modelled profiles and they significantly enhance the ground motion model derivation. The similarity between the theoretical transfer function from the V (S) profile and the observed amplification from vertical array stations is also excellent.
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    Characterisation of the Groningen subsurface for seismic hazard and risk modelling
    Kruiver, Pauline P.; Wiersma, Ane; Kloosterman, Fred H.; de Lange, Ger; Korff, Mandy; Stafleu, Jan; Busschers, Freek S.; Harting, Ronald; Gunnink, Jan L.; Green, Russell A.; van Elk, Jan; Doornhof, Dirk (2017-12)
    The shallow subsurface of Groningen, the Netherlands, is heterogeneous due to its formation in a Holocene tidal coastal setting on a periglacially and glacially inherited landscape with strong lateral variation in subsurface architecture. Soft sediments with low, small-strain shear wave velocities (VS30 around 200ms(-1)) are known to amplify earthquake motions. Knowledge of the architecture and properties of the subsurface and the combined effect on the propagation of earthquake waves is imperative for the prediction of geohazards of ground shaking and liquefaction at the surface. In order to provide information for the seismic hazard and risk analysis, two geological models were constructed. The first is the ` Geological model for Site response in Groningen' (GSG model) and is based on the detailed 3D GeoTOP voxel model containing lithostratigraphy and lithoclass attributes. The GeoTOP model was combined with information from boreholes, cone penetration tests, regional digital geological and geohydrological models to cover the full range from the surface down to the base of the North Sea Supergroup (base Paleogene) at similar to 800m depth. The GSG model consists of a microzonation based on geology and a stack of soil stratigraphy for each of the 140,000 grid cells (100m x 100 m) to which properties (VS and parameters relevant for nonlinear soil behaviour) were assigned. The GSG model serves as input to the site response calculations that feed into the Ground Motion Model. The second model is the ` Geological model for Liquefaction sensitivity in Groningen' (GLG). Generally, loosely packed sands might be susceptible to liquefaction upon earthquake shaking. In order to delineate zones of loosely packed sand in the first 40m below the surface, GeoTOP was combined with relative densities inferred from a large cone penetration test database. The marine Naaldwijk and Eem Formations have the highest proportion of loosely packed sand (31% and 38%, respectively) and thus are considered to be the most vulnerable to liquefaction; other units contain 5-17% loosely packed sand. The GLG model serves as one of the inputs for further research on the liquefaction potential in Groningen, such as the development of region-specific magnitude scaling factors (MSF) and depth-stress reduction relationships (r(d)).
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    A database of ground motion recordings, site profiles, and amplification factors from the Groningen gas field in the Netherlands
    Ntinalexis, Michail; Kruiver, Pauline P.; Bommer, Julian J.; Ruigrok, Elmer; Rodriguez-Marek, Adrian; Edwards, Ben; Pinho, Rui; Spetzler, Jesper; Hernandez, Edwin Obando; Pefkos, Manos; Bahrampouri, Mahdi; van Onselen, Erik P.; Dost, Bernard; van Elk, Jan (Sage Publications, 2023-02)
    A comprehensive database that has been used to develop ground motion models for induced earthquakes in the Groningen gas field is provided in a freely accessible online repository. The database includes more than 8500 processed ground motion recordings from 87 earthquakes of local magnitude M-L between 1.8 and 3.6, obtained from a large network of surface accelerographs and borehole geophones placed at 50 m depth intervals to a depth of 200 m. The 5%-damped pseudo-acceleration spectra and Fourier amplitude spectra of the records are also provided. Measured shear-wave velocity (V-S) profiles, obtained primarily from seismic Cone Penetration Tests (CPTs), are provided for 80 of the similar to 100 recording stations. A model representing the regional dynamic soil properties is presented for the entire gas field plus a 5 km onshore buffer zone, specifying lithology, V-S, and damping for all layers above the reference baserock horizon located at about 800 m depth. Transfer functions and frequency-dependent amplification factors from the reference rock horizon to the surface for the locations of the recording stations are also included. The database provides a valuable resource for further refinement of induced seismic hazard and risk modeling in Groningen as well as for generic research in site response of thick, soft soil deposits and the characteristics of ground motions from small-magnitude, shallow-focus induced earthquakes.
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    Developing a model for the prediction of ground motions due to earthquakes in the Groningen gas field
    Bommer, Julian J.; Dost, Bernard; Edwards, Benjamin; Kruiver, Pauline P.; Ntinalexis, Michail; Rodriguez-Marek, Adrian; Stafford, Peter J.; van Elk, Jan (2017-12)
    Major efforts are being undertaken to quantify seismic hazard and risk due to production-induced earthquakes in the Groningen gas field as the basis for rational decision-making about mitigation measures. An essential element is a model to estimate surface ground motions expected at any location for each earthquake originating within the gas reservoir. Taking advantage of the excellent geological and geophysical characterisation of the field and a growing database of ground-motion recordings, models have been developed for predicting response spectral accelerations, peak ground velocity and ground-motion durations for a wide range of magnitudes. The models reflect the unique source and travel path characteristics of the Groningen earthquakes, and account for the inevitable uncertainty in extrapolating from the small observed magnitudes to potential larger events. The predictions of ground-motion amplitudes include the effects of nonlinear site response of the relatively soft near-surface deposits throughout the field.
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    Ground-motion prediction models for induced earthquakes in the Groningen gas field, the Netherlands
    Bommer, Julian J.; Stafford, Peter J.; Ruigrok, Elmer; Rodriguez-Marek, Adrian; Ntinalexis, Michail; Kruiver, Pauline P.; Edwards, Benjamin; Dost, Bernard; van Elk, Jan (Springer, 2022-12)
    Small-magnitude earthquakes induced by gas production in the Groningen field in the Netherlands have prompted the development of seismic risk models that serve both to estimate the impact of these events and to explore the efficacy of different risk mitigation strategies. A core element of the risk modelling is ground-motion prediction models (GMPM) derived from an extensive database of recordings obtained from a dense network of accelerographs installed in the field. For the verification of damage claims, an empirical GMPM for peak ground velocity (PGV) has been developed, which predicts horizontal PGV as a function of local magnitude, M-L; hypocentral distance, R-hyp; and the time-averaged shear-wave velocity over the upper 30 m, V-S30. For modelling the risk due to potential induced and triggered earthquakes of larger magnitude, a GMPM for response spectral accelerations has been developed from regressions on the outputs from finite-rupture simulations of motions at a deeply buried rock horizon. The GMPM for rock motions is coupled with a zonation map defining frequency-dependent non-linear amplification factors to obtain estimates of surface motions in the region of thick deposits of soft soils. The GMPM for spectral accelerations is formulated within a logic-tree framework to capture the epistemic uncertainty associated with extrapolation from recordings of events of M-L <= 3.6 to much larger magnitudes.
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    Incorporating dwelling mounds into induced seismic risk analysis for the Groningen gas field in the Netherlands
    Kruiver, Pauline P.; Pefkos, Manos; Meijles, Erik; Aalbersberg, Gerard; Campman, Xander; van der Veen, Wim; Martin, Antony; Ooms-Asshoff, Kira; Bommer, Julian J.; Rodriguez-Marek, Adrian; Pinho, Rui; Crowley, Helen; Cavalieri, Francesco; Correia, Antonio A.; van Elk, Jan (2021-09-24)
    In order to inform decision-making regarding measures to mitigate the impact of induced seismicity in the Groningen gas field in the Netherlands, a comprehensive seismic risk model has been developed. Starting with gas production scenarios and the consequent reservoir compaction, the model generates synthetic earthquake catalogues which are deployed in Monte Carlo analyses, predicting ground motions at a buried reference rock horizon that are combined with nonlinear amplification factors to estimate response spectral accelerations at the surface. These motions are combined with fragility functions defined for the exposed buildings throughout the region to estimate damage levels, which in turn are transformed to risk in terms of injury through consequence functions. Several older and potentially vulnerable buildings are located on dwelling mounds that were constructed from soils and organic material as a flood defence. These anthropogenic structures are not included in the soil profile models used to develop the amplification factors and hence their influence has not been included in the risk analyses to date. To address this gap in the model, concerted studies have been identified to characterize the dwelling mounds. These include new shear-wave velocity measurements that have enabled dynamic site response analyses to determine the modification of ground shaking due to the presence of the mound. A scheme has then been developed to incorporate the dwelling mounds into the risk calculations, which included an assessment of whether the soil-structure interaction effects for buildings founded on the mounds required modification of the seismic fragility functions.
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    An integrated shear-wave velocity model for the Groningen gas field, The Netherlands
    Kruiver, Pauline P.; van Dedem, Ewoud; Romijn, Remco; de Lange, Ger; Korff, Mandy; Stafleu, Jan; Gunnink, Jan L.; Rodriguez-Marek, Adrian; Bommer, Julian J.; van Elk, Jan; Doornhof, Dirk (2017-09)
    A regional shear-wave velocity (V-S) model has been developed for the Groningen gas field in the Netherlands as the basis for seismic microzonation of an area of more than 1000 km(2). The V-S model, extending to a depth of almost 1 km, is an essential input to the modelling of hazard and risk due to induced earthquakes in the region. The detailed V-S profiles are constructed from a novel combination of three data sets covering different, partially overlapping depth ranges. The uppermost 50 m of the V-S profiles are obtained from a high-resolution geological model with representative V-S values assigned to the sediments. Field measurements of V-S were used to derive representative V-S values for the different types of sediments. The profiles from 50 to 120 m are obtained from inversion of surface waves recorded (as noise) during deep seismic reflection profiling of the gas reservoir. The deepest part of the profiles is obtained from sonic logging and V-P-V-S relationships based on measurements in deep boreholes. Criteria were established for the splicing of the three portions to generate continuous models over the entire depth range for use in site response calculations, for which an elastic half-space is assumed to exist below a clear stratigraphic boundary and impedance contrast encountered at about 800 m depth. In order to facilitate fully probabilistic site response analyses, a scheme for the randomisation of the V-S profiles is implemented.