Academic Journal

Time Domain Source Parameter Estimation of Natural and Man-Induced Microearthquakes at the Geysers Geothermal Field

التفاصيل البيبلوغرافية
العنوان: Time Domain Source Parameter Estimation of Natural and Man-Induced Microearthquakes at the Geysers Geothermal Field
المؤلفون: Longobardi V., Nazeri S., Colombelli S., Rea R., De Landro G., Zollo A.
المساهمون: Longobardi, V., Nazeri, S., Colombelli, S., Rea, R., De Landro, G., Zollo, A.
سنة النشر: 2023
المجموعة: IRIS Università degli Studi di Napoli Federico II
مصطلحات موضوعية: earthquake source parameter, induced seismicity, The Geysers geothermal field, time domain technique
الوصف: Water injection in geothermal areas is the preferential strategy to sustain the natural production of geothermal resources. In this context, monitoring microearthquakes is a fundamental tool to track changes in the reservoirs in terms of soil composition, response to injections, and resource exploitation with space and time. Therefore, refined source characterization is crucial to better estimate the size, source mechanism, and rupture process of microearthquakes, as they are possibly related to industrial activities, and to identify any potential variation in the background seismicity. Standard approaches for source parameter estimation are ordinarily based on the modelling of Fourier displacement spectra and its characteristic parameters: the low-frequency spectral level and corner frequency. Here, we apply an innovative time domain technique that uses the curves of P-wave amplitude vs. time along the seismogram. This methodology allows estimation of seismic moment, source radius, and stress release from the plateau level and the corner time of the average logarithm of P-wave displacement versus time with the assumption of a triangular moment rate function, uniform rupture speed, and a constant/frequency-independent Q-factor. In the current paper, this time domain methodology is implemented on a selected catalog of microearthquakes consisting of 83 events with a moment magnitude ranging between 1.0 and 1.5 that occurred during a 7-year period (2007–2014) of fluid extraction/injection around Prati-9 and Prati-29 wells at The Geysers geothermal field. The results show that the time domain technique provides accurate seismic moment (moment magnitude) and rupture duration/radius estimates of microearthquakes down to the explored limit (M 1) while accounting for the anelastic attenuation effect in the radiated high-frequency wavefield. The retrieved source radius vs. moment scaling is consistent with a self-similar, constant stress drop scaling model, which proves an appropriate attenuation correction and the ...
نوع الوثيقة: article in journal/newspaper
اللغة: English
Relation: info:eu-repo/semantics/altIdentifier/wos/WOS:000930406400001; volume:16; issue:3; firstpage:1121; journal:ENERGIES; https://hdl.handle.net/11588/921968; info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85147955366
DOI: 10.3390/en16031121
الاتاحة: https://hdl.handle.net/11588/921968
https://doi.org/10.3390/en16031121
Rights: info:eu-repo/semantics/openAccess
رقم الانضمام: edsbas.BAAB1F66
قاعدة البيانات: BASE