Ambient noise multimode Rayleigh and Love wave tomography to determine the shear velocity structure above the Groningen gas field

Abstract

SUMMARY The Groningen gas field is one of the largest gas fields in Europe. The continuous gas extraction led to an induced seismic activity in the area. In order to monitor the seismic activity and study the gas field many permanent and temporary seismic arrays were deployed. In particular, the extraction of the shear wave velocity model is crucial in seismic hazard assessment. Local S-wave velocity-depth profiles allow us the estimation of a potential amplification due to soft sediments. Ambient seismic noise tomography is an interesting alternative to traditional methods that were used in modelling the S-wave velocity. The ambient noise field consists mostly of surface waves, which are sensitive to the Swave and if inverted, they reveal the corresponding S-wave structures. In this study, we present results of a depth inversion of surface waves obtained from the cross-correlation of 1 month of ambient noise data from four flexible networks located in the Groningen area. Each block consisted of about 400 3-C stations. We compute group velocity maps of Rayleigh and Love waves using a straight-ray surface wave tomography. We also extract clear higher modes of Love and Rayleigh waves. The S-wave velocity model is obtained with a joint inversion of Love and Rayleigh waves using the Neighbourhood Algorithm. In order to improve the depth inversion, we use the mean phase velocity curves and the higher modes of Rayleigh and Love waves. Moreover, we use the depth of the base of the North Sea formation as a hard constraint. This information provides an additional constraint for depth inversion, which reduces the S-wave velocity uncertainties. The final S-wave velocity models reflect the geological structures up to 1 km depth and in perspective can be used in seismic risk modelling.

A Multi‐Hydrogeophysical Study of a Watershed at Kaiwi Coast (Oʻahu, Hawaiʻi), using Seismic Ambient Noise Surface Wave Tomography and Self‐Potential Data

“…Here we only used the vertical component of the seismic data to obtain the highest lateral resolution possible, using every stations. But it is possible to use the horizontal components as well to measure, for example, Love-wave dispersion (Chmiel et al, 2019), Horizontal-to-vertical spectral ratios (Spica et al, 2018), or Rayleigh wave ellipticity (Berg et al, 2018). The Love wave information would help to constrain the velocity structure while Horizontal-to-vertical spectral ratio or the ellipticity information would better constrain the depth of the layer interfaces in the subsurface.…”

“…Ambient noise tomography has been applied to many types of studies, primarily in seismology, to image large crustal-scale structures (Gudmundsson et al, 2007;Lin et al, 2008;Shapiro et al, 2005;Yao et al, 2006), but also at smaller scale, especially to image the subsurface of volcanic islands (Brenguier et al, 2007;Jeddi et al, 2017;Lee et al, 2021;Luzón et al, 2011;Matos et al, 2015;Mordret et al, 2015;Obermann et al, 2016;Ryberg et al, 2017;Villagómez et al, 2011). In recent years, the value of ambient noise tomography for studying high-resolution near-surface structures has been recognized (Chmiel et al, 2019;de Ridder & Dellinger, 2011;Lin et al, 2013;Mordret et al, 2013;Picozzi et al, 2009), but applications for hydrological purposes are still very scarce. Most hydrological studies thus far have targeted temporal monitoring of groundwater resources (Clements & Denolle, 2018;Garambois et al, 2019;Lecocq et al, 2017;Mainsant et al, 2012;Sens-Schönfelder & Wegler, 2006;Voisin et al, 2016).…”

Comparison of MASW and seismic interferometry with use of ambient noise for estimation of S-wave velocity field in landslide subsurface

“…Body waves, in comparison with surface waves, have broader applications in geoengineering (Szreder et al 2008;Pilecki 2008;Pilecki et al 2017); however, methods based on surface waves such as MASW and SI quickly develop improving range and resolution of investigation (Kanli et al 2006(Kanli et al , 2008Chmiel et al 2019). The use of low-frequency noise below 0.4 Hz allows to image geological subsurface up to approximately 400-500 m (Czarny et al 2019).…”

Ambient Noise Tomography of Upper Crustal Structures and Quaternary Faults in the Seoul Metropolitan Area and Its Geological Implications

“…Igneous intrusions in the fault zones are imaged to be high velocity anomalies in the urban areas (Gu et al, 2019;Huang et al, 2010). The low velocity zone is correlated with high heat flow, magma chamber, and sediment distribution (Brenguier et al, 2007;Chmiel et al, 2019;Li et al, 2016;Obermann et al, 2013;Shirzad & Shomali, 2014;Young et al, 2011).…”

“…The spatial resolution in the ambient noise tomography is dependent on the interstation spacing. High resolution studies are applied for local regions including petroleum reservoir, fault, urban and complex geological areas based on seismic arrays, with imaging depths of ∼1 to several kilometers (Brenguier et al, 2007;Chmiel et al, 2019;Green et al, 2017;Li et al, 2016;Mordret et al, 2014;Nakata et al, 2015;Obermann et al, 2016;Picozzi et al, 2009;Pilz et al, 2013;Shirzad & Shomali, 2014).…”