Induced Seismicity Consortium (ISC) Quarterly Review Meeting, Q2-2013 Quantifying Seismic Hazard from Subsurface Fluid Injection and Production (SFIP) for Shale Gas and Oil Reservoirs RPSEA-RFP2012UN001 Fred Aminzadeh / Debotyam Maity, Los Angeles, CA, July 2, 2013
Sites in North America with documented IS caused by or likely related to energy developments (NRC Report, 2012). • Main Research Areas • Novel data acquisition program to utilize perf shots as controlled sources. • Utilize MEQ/ EM data through optimized “dual-array” survey design. • Characterize subsurface geomechanics for improved understanding of stress regimes, etc. • Model relationships between seismicity, derived attributes and UOG operational parameters • Hazard prediction (in relation to IS) tools and mitigation framework. Objectives MEQ characterization and observation of possible fault activation with low b-values (Maxwell et al., 2011)
Schematic representation of SWP system for potential deployment under actual field conditions. Task 1: Seismic while perforation (SWP) Applicability limited to completions involving perforations Research necessary to understand the limits of perfs as sources Characterize formations of interest for necessary elements within modeling framework DELIVERABLES • Design of basic framework including in-depth analysis of design, deployment and processing/ analysis issues. • Preliminary processing & analysis based on defined framework to validate this novel technique.
Task 2: Joint EM/ MEQ survey Synchronized time lapse EM/ MEQ data collection Real time injection & fluid front control to reduce IS hazards (a) MEQ tomography (Lees et al., 2000) and (b) MT tomography (Newman et al., 2008) for Coso Geothermal field. Optimization results for 4 wellbore arrays based on moment tensor inversion workflow. (Maity et al., 2013a) Joint optimization approach to minimize costs and maximize operational benefits DELIVERABLES • Optimum survey design methodology for joint EM/ MEQ surveys (multi-array deployments). • Spatially & temporally cataloged geophysical data from test site for future reference.
Microseismic Waves Created By Small-Scale Fracturing Observation Well Surface Sources + Receivers Geologic Model Velocity Model Treatment Well Vertical + Lateral Target Formation
(a) Bulk Modulus, (b) Hydrostatic stress, (c) Tangential weakness, (d) fracture attribute, (e) Extensional stress, (f) Normal weakness, (g) Fracture expandability and (h) fracture permeability mapped using MEQ data from a geothermal field (Maity et al., 2013b) Task 3: Characterizing reservoir properties Better understand in-situ geomechanics to improve injection Avoid areas of potential concern based on mapped attributes (a) (b) (c) (d) Maximize utilization of collected and interpreted data (Task 2). (e) (f) (g) (h) DELIVERABLES • Geomechanical and other reservoir property models including uncertainty estimates.
Task 4: ANN for Modeling Induced Seismicity DELIVERABLES • Use ANN to model induced seismicity, operational regime and geophysical attributes. Predictive tool to better understand seismicity as it relates to observed attributes SFIP Operational Parameters
Hierarchicalprobabilistic model to predict failure Task 5: Probabilistic models for Seismicity Extensive uncertainty and risk analysis Model parameters to reflect subscale effects, based on MaxEnt. Understanding impact of uncertainty on final hazard estimates DELIVERABLES • A hierarchical probabilistic model for the operational parameters which is calibrated based upon the collected seismic data • Hazards maps that reflect the interaction between uncertainties, models, and risks and that provide a visual aid for decision-making.
Task 6: Hazard mitigation Designed complexity to incorporate complex intra-property relationships Traffic Light system (Bommer et al. 2006) Real time data acquisition/ analysis Typical evaluations needed for hazard and risk analysis (NRC Report, 2012) DELIVERABLES • A “Safe SFIP Operation” system for different operational parameters and related conditions. Necessary documentation support for software modeling tool and expandability will be critical in the design approach selected.