Microseismic monitoring — Introduction

PreviousNext You have accessGEOPHYSICSVolume 80, Issue 6Microseismic monitoring — IntroductionAuthors: Vladimir GrechkaBrad ArtmanLeo EisnerWerner HeiglStephen WilsonVladimir GrechkaMarathon Oil, Houston, Texas, USA. E-mail: .Search for more papers by this authorEmail the author at [email protected], Brad ArtmanSpectraseis, Denver, Colorado, USA. E-mail: .Search for more papers by this authorEmail the author at [email protected], Leo EisnerIRSM Academy of Sciences of the Czech Republic, Prague, Czech Republic. E-mail: .Search for more papers by this authorEmail the author at [email protected], Werner HeiglApache Corporation, Houston, Texas, USA. E-mail: .Search for more papers by this authorEmail the author at [email protected], and Stephen WilsonSeismogenic, Houston, Texas, USA. E-mail: .Search for more papers by this authorEmail the author at [email protected]https://doi.org/10.1190/2015-0917-SPSEINTRO.1 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Most papers the readers find in this special section were presented at the First International Workshop on Microseismic Technology held in Asheville, North Carolina, USA, on 17–22 August 2014. The workshop’s organizing and technical program committee consisted of Werner Heigl (Apache Corporation), Vladimir Grechka (Marathon Oil), Leo Eisner (IRSM Academy of Sciences of the Czech Republic), Christophe Maisons (Magnitude), Serge Shapiro (Freie University, Berlin), Julie Shemeta (MEQ Geo), and Stephen Wilson (Seismogenic). The workshop, designed to facilitate sharing of microseismic expertise and the key observations and findings, was organized with special attention to balancing the needs of industry and academia. To encourage participation from the industry, only brief abstracts of papers were requested and no recording was permitted at the workshop; to attract academic contributions, the special section in Geophysics was offered to authors who would be willing to develop their workshop presentations into full-scale papers. The workshop, attended by 80 geophysicists and engineers from 11 countries, was enthusiastically supported by operating and service companies, with sponsorship from ITASCA, Magnitude, Marathon Oil, Pinnacle, Read, Sigma3, and Weatherford covering coffee breaks and lunches, and providing travel grants to several students who would not be able to attend the workshop otherwise.The twelve papers selected for this special section discuss microseismic data acquisition, data processing, computation of event hypocenters, velocity-model building, seismic source characterization, and the physics of hydraulic fracturing.Data acquisitionVaezi and van der Baan apply seismic interferometry to assess the quality of clamping of downhole geophone arrays. They show that poorly clamped geophones yield predominantly tube waves or incoherent waveforms on retrieved crosscorrelation gathers, whereas well-clamped geophones produce gathers containing clearly identifiable body waves propagating along observation wells.Data processingCastellanos and van der Baan use multiplet analysis to assess the quality of processing of microseismic events that belong to the same multiplet group. Analyzing histograms of differential times between events with highly correlated waveforms, the authors detect traveltime-picking errors and inconsistencies in derived source mechanisms.Reshetnikov et al. present a technique for reflection seismic imaging with passive data that relies on polarization analysis to mitigate insufficient data aperture and reduce imaging artifacts. The technique, applied to microseismic data recorded during and after stimulation of the geothermal system in Basel, Switzerland, is shown to reveal permeable fluid pathways characterized by a low number of induced seismic events.Velis et al. present a method to automatically detect and denoise microseismic events in 3C multichannel records. The events are detected with a pattern-recognition approach and, once detected, denoised with a reduced-rank approximation of the singular value decomposition of the data. Tests on synthetic and field data demonstrate the reliability and effectiveness of the proposed method in the presence of substantial noise.Hypocenter locationBelayouni et al. develop a global grid search method for computing hypocenters of microseismic events and apply it to synthetic data and field data from Cotton Valley. Their method, an implementation of the Bayesian probabilistic approach, enables the computation of hypocenter uncertainties, essential for quantifying the quality of the results.Grechka et al. propose a technique for relative location of microseismic events. They apply the paraxial ray method for a master event to compute the relative locations of adjacent microseismic events at appreciable distances from the master. Tests of the relative location technique on synthetic and field microseismic data illustrate its accuracy, computational efficiency, and insensitivity to velocity errors.Price et al. examine the influence of high velocity layers in the subsurface on the quality of hypocenters obtained in surface microseismic monitoring. The authors identify reduction in the effective array aperture and generation of strong seismic coda as the two most important factors responsible for poor resolution of imaged events and enhanced errors in their hypocenters.Van Renterghem et al. analyze the accuracy of perforation-shot location estimates in a data set acquired with downhole and surface receiver arrays in the Fayetteville Field. They emphasize the importance of incorporating the regional dip of about 1.6° and velocity anisotropy, typically between 40% and 50% in the Fayetteville shales, for obtaining accurate shot locations.Velocity-model buildingWitten and Shragge introduce extended imaging conditions for passive wave-equation imaging algorithms. The proposed imaging conditions, shown to be applicable to 3C records, are sensitive to the P- and S-wave velocity perturbations, allowing one to update the velocities and improve the image.Grechka develops a method for building effective transversely isotropic models with tilted symmetry axes (TTI) for processing of surface microseismic and applies the method to a data set collected in the Eagle Ford Field. He shows that the constructed TTI model focuses perforation-shot and event data better than a conventional layered isotropic velocity model constructed to process the data set.Seismic source characterizationFolesky et al. complement the standard seismic moment tensor inversion by determining the direction of rupture propagation, allowing them to discriminate the fault plane and the auxiliary plane of focal mechanisms. Their method, applied to data from the Basel geothermal reservoir, indicates the process of rock failure to be preferentially directed from the periphery toward the injection source, corroborating the recently proposed hypothesis that triggering of induced events is more probable on preexisting faults than on newly created fractures.Physics of hydraulic fracturingLangenbruch and Shapiro compare heterogeneity measured on sonic logs to features of microseismic events caused by hydraulic fracturing. Their analysis of two data sets suggests the injection-triggered seismicity to be controlled by in situ heterogeneity through the fluctuations of localized stresses in heterogeneous rocks.FiguresReferencesRelatedDetailsCited bySignal-to-noise ratio enhancement for downhole microseismic data based on 3D shearlet transformJuan Li, Yuan Li, Shou Ji, Yue Li, and Zhihong Qian10 April 2019 | GEOPHYSICS, Vol. 84, No. 3Microseismic data SNR enhancement using local projection denoising method13 September 2018 | Journal of Geophysics and Engineering, Vol. 15, No. 6SNR enhancement for downhole microseismic data based on scale classification shearlet transform21 February 2018 | Journal of Geophysics and Engineering, Vol. 15, No. 3Downhole microseismic signal-to-noise ratio enhancement via strip matching shearlet transform5 February 2018 | Journal of Geophysics and Engineering, Vol. 15, No. 2References31 August 2017Research on the development of heterogeneous network transmission system for seismic exploration wireless data acquisition7. Seismic, rock physics, spatial models, and their integration in reservoir geophysicsMiguel Bosch, Tapan Mukerji, and Ezequiel F. Gonzalez15 May 2017 Volume 80Issue 6Nov 2015Pages: 1ND-Z124ISSN (print):0016-8033 ISSN (online):1942-2156 publication data© 2015 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 20 Oct 2015Published in print: 01 Nov 2015 CITATION INFORMATION Vladimir Grechka, Brad Artman, Leo Eisner, Werner Heigl, and Stephen Wilson, (2015), "Microseismic monitoring — Introduction," GEOPHYSICS 80: WCi-WCii. https://doi.org/10.1190/2015-0917-SPSEINTRO.1 Plain-Language Summary PDF Download Metrics Loading ...