Joint inversion of converted and surface waves for characterization of geothermal fields

2021 ◽  
Author(s):  
Ivan Granados Chavarria ◽  
Marco Calò ◽  
Thomas Bodin ◽  
Angel Figueroa Soto
Keyword(s):  
Group Velocity Dispersion ◽  
Joint Inversion ◽  
Seismic Station ◽  
Regional Scale ◽  
Geothermal Field ◽  
Horizon 2020 ◽  
Geothermal Fields ◽  
Converted Phases ◽  
Converted Waves

<p>Joint inversion of surfaces and teleseismic converted waves is commonly used to retrieve seismic structures beneath a seismic station. Currently, this approach is routinely applied at global and regional scale to probe the structures of the mantle and the lower-crust. However, the difficulty to retrieve reliable converted waves at high frequencies (> 1 Hz) makes challenging to apply this technique to resolve structures at shallow depths (<20 km). Here we explore the feasibility of using a trans-dimensional Bayesian scheme based on a reversible jump Markov Chains Monte Carlo method, to resolve shallow structure at local scale. We use phase and group velocity dispersion curves for Love and Rayleigh waves, from 0.5 to 10 s and tele-seismic converted waves in a distance range from 30<sup>o</sup> to 95<sup>o</sup>. We explore the ability of different approaches to retrieve high frequency converted phases that will be used in the framework of the Bayesian inversion. We present preliminary tests of the reliability of the method and applications to experimental data collected in the super-hot geothermal field of Los Humeros, México. This work is performed in the framework of the Mexican European consortium GeMex (Cooperation in Geothermal energy research Europe-Mexico, PT5.2 N: 267084 funded by CONACyT-SENER: S0019, 2015-04, and Horizon 2020, grant agreement No. 727550).</p>

scholarly journals Fluid activity detection in geothermal areas using a single seismic station by monitoring horizontal-to-vertical spectral ratios

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kyosuke Okamoto ◽  
Hiroshi Asanuma ◽  
Hiro Nimiya
Keyword(s):  
Carbon Capture ◽  
Seismic Station ◽  
Carbon Capture And Storage ◽  
Fluid Flows ◽  
Temporal Variations ◽  
Geothermal Field ◽  
Spectral Ratios ◽  
Subsurface Structures ◽  
Geothermal Fields ◽  
Single Station

AbstractSubsurface structure survey based on horizontal-to-vertical (H/V) spectral ratios is widely conducted. The major merit of this survey is its convenience to obtain a stable result using a single station. Spatial variations of H/V spectral ratios are well-known phenomena, and it has been used to estimate the spatial fluctuation in subsurface structures. It is reasonable to anticipate temporal variations in H/V spectral ratios, especially in areas like geothermal fields, carbon capture and storage fields, etc., where rich fluid flows are expected, although there are few reports about the temporal changes. In Okuaizu Geothermal Field (OGF), Japan, dense seismic monitoring was deployed in 2015, and continuous monitoring has been consistent. We observed the H/V spectral ratios in OGF and found their repeated temporary drops. These drops seemed to be derived from local fluid activities according to a numerical calculation. Based on this finding, we examined a coherency between the H/V spectral ratios and fluid activities in OGF and found a significance. In conclusion, monitoring H/V spectral ratios can enable us to grasp fluid activities that sometimes could lead to a relatively large seismic event.

scholarly journals Local earthquake tomography at the Los Humeros geothermal field, Mexico

2020 ◽  
Author(s):  
Tania Toledo ◽  
Philippe Jousset ◽  
Emmanuel Gaucher ◽  
Hansruedi Maurer ◽  
Charlotte Krawzcyzk ◽  
...  
Keyword(s):  
Joint Inversion ◽  
Detection Algorithm ◽  
Geothermal Field ◽  
Volcanic Complex ◽  
Geothermal Systems ◽  
The European Union ◽  
Injection Wells ◽  
Geothermal Resources ◽  
Seismic Stations ◽  
Horizon 2020

<p>The GEMex<sup>*</sup> project is a recently finalized European-Mexican collaboration that aimed to improve the understanding of two geothermal fields: Acoculco and Los Humeros Volcanic Complex . These sites are located in the Trans-Mexican Volcanic Belt, a region that hosts numerous active volcanoes and is favorable for geothermal exploitation. Currently, the  Los Humeros Volcanic Complex is one of Mexico’s main geothermal systems with an installed capacity of ~95MW. Many studies have been performed at this site since the 70s highlighting several features and characteristics of the shallow subsurface. However a thorough knowledge of structures and behavior of the system at greater depths is still quite sparse. Hence one main objective of the GEMex project was to conduct several geological, geochemical, and geophysical experiments to investigate deeper structures for future development of local and regional geothermal resources.</p><p>In this framework, for the period of one year (September 2017 to September 2018), a seismic array consisting of 45 seismic stations was set to record continuously at the Los Humeros Volcanic Complex. In this study we analyzed the continuous seismic records to detect the micro-seismicity mainly related to exploitation activities. After applying a recursive STA/LTA detection algorithm, we assembled and manually picked P- and S- phases of a catalog of about 500 local events. The detected events were mostly clustered around injection wells, with fewer events located close to known structures. We use the retrieved catalog to derive a new minimum 1D velocity model for the Los Humeros site. We then performed a joint inversion to obtain the 3D Vp and Vp/Vs structures of the geothermal field. A post-processing averaging of several inversions was also computed to increase resolution of the investigated region. In this study we will show the derived Vp and Vp/Vs models for the  Los Humeros Volcanic Complex to emphasize various underground structures and potentially identify possible variations due to changes in temperature, fluid content, and rock porosity.</p><p> </p><p>*This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 727550 and the Mexican Energy Sustainability Fund CONACYT-SENER, project 2015-04-68074. We thank the Comisión Federal de Electricidad (CFE) for kindly granting the access to the geothermal field for installation and maintenance of seismic stations.</p>

scholarly journals Spatial and temporal multiplet analysis for identification of dominant fluid migration path at The Geysers geothermal field, California

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. Staszek ◽  
Ł. Rudziński ◽  
G. Kwiatek
Keyword(s):  
Temporal Analysis ◽  
Geothermal Field ◽  
Fluid Injection ◽  
Fluid Migration ◽  
Multiple Events ◽  
Spatial And Temporal Analysis ◽  
Hydraulic Conditions ◽  
The Geysers ◽  
Multiplet Analysis

AbstractMultiplet analysis is based on the identification of seismic events with very similar waveforms which are used then to enhance seismological analysis e.g. by precise relocation of sources. In underground fluid injection conditions, it is a tool frequently used for imaging of subsurface fracture system. We identify over 150 repeatedly activated seismic sources within seismicity cluster induced by fluid injection in NW part of The Geysers geothermal field (California). Majority of multiple events (ME) occur along N–S oriented planar structure which we interpret as a fault plane. Remaining ME are distributed along structures interpreted as fractures, forming together a system of interconnected cracks enabling fluid migration. Temporal analysis reveals that during periods of relatively low fluid injection the proportion of ME to non-multiple events is higher than during periods of high injection. Moreover, ME which occur within the fault differ in activity rate and source properties from ME designating the fractures and non-multiple events. In this study we utilize observed differences between ME occurring within various structures and non-multiple events to describe hydraulic conditions within the reservoir. We show that spatial and temporal analysis of multiplets can be used for identification and characterization of dominant fluid migration paths.

scholarly journals Using the Paratunsky geothermal field to provide heating for Kamchatka

2019 ◽  
pp. 21-33
Author(s):  
A. V. Kiryukhin ◽  
N. B. Zhuravlev
Keyword(s):  
Waste Water ◽  
Thermal Energy ◽  
Thermal Water ◽  
Discharge Rate ◽  
Local Heating ◽  
Geothermal Field ◽  
Heat Energy ◽  
Heating Systems ◽  
Geothermal Fields ◽  
Potential Market

The Paratunsky geothermal field has been in operation since 1964, mostly in a self-flowing mode, with a discharge rate of approximately 250 kg/s of thermal water at temperatures of 70–90°С (47 Mw, with the waste water having a temperature of 35°С). The water drawn from the field is used for local heating, spa heating, and for greeneries in the villages of Paratunsky and Termal’nyi (3000 residents). The potential market of thermal energy in Kamchatka includes Petropavlovsk-Kamchatskii (180000 residents), Elizovo (39 000), and Vilyuchinsk (22 000). The heat consumption in the centralized heating systems for Petropavlovsk-Kamchatskii is 1 623 000 GCal per annum (216 Mw). A thermohydrodynamic model developed previously is used to show that the Paratunsky geothermal reservoir can be operated in a sustainable mode using submersible pumps at an extraction rate of as much as 1375 kg/s, causing a moderate decrease in pressure (by no more than 8 bars) and temperature (by no more than 4°С) in the reservoir. Additional geothermal sources of heat energy may include the Verkhne-Paratunsky and Mutnovsky geothermal fields.

Landscape Biodiversity Characterization in Ecoregion 29 Using MODIS

2013 ◽  
pp. 815-831
Author(s):  
Nitin Kumar Tripathi ◽  
Aung Phey Khant
Keyword(s):  
Climate Change ◽  
Remote Sensing ◽  
Global Warming ◽  
Forest Type ◽  
Regional Scale ◽  
Remote Sensing Data ◽  
Modis Data ◽  
Moderate Resolution ◽  
Landscape Biodiversity

Biodiversity conservation is a challenging task due to ever growing impact of global warming and climate change. The chapter discusses various aspects of biodiversity parameters that can be estimated using remote sensing data. Moderate resolution satellite (MODIS) data was used to demonstrate the biodiversity characterization of Ecoregion 29. Forest type map linked to density of the study area was also developed by MODIS data. The outcome states that remote sensing and geographic information systems can be used in combination to derive various parameters related to biodiversity surveillance at a regional scale.

scholarly journals Characterization of Surface Evidence of Groundwater Flow Systems in Continental Mexico

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2459
Author(s):  
Alessia Kachadourian-Marras ◽  
Margarita M. Alconada-Magliano ◽  
José Joel Carrillo-Rivera ◽  
Edgar Mendoza ◽  
Felipe Herrerías-Azcue ◽  
...  
Keyword(s):  
Groundwater Flow ◽  
Water Cycle ◽  
Regional Scale ◽  
Ground Surface ◽  
The Public ◽  
Groundwater Flow Systems ◽  
Human Needs ◽  
Flow Systems ◽  
Vegetation And Climate

The dynamics of the underground part of the water cycle greatly influence the features and characteristics of the Earth’s surface. Using Tóth’s theory of groundwater flow systems, surface indicators in Mexico were analyzed to understand the systemic connection between groundwater and the geological framework, relief, soil, water bodies, vegetation, and climate. Recharge and discharge zones of regional groundwater flow systems were identified from evidence on the ground surface. A systematic hydrogeological analysis was made of regional surface indicators, published in official, freely accessible cartographic information at scales of 1:250,000 and 1:1,000,000. From this analysis, six maps of Mexico were generated, titled “Permanent water on the surface”, “Groundwater depth”, “Hydrogeological association of soils”, “Hydrogeological association of vegetation and land use”, “Hydrogeological association of topoforms”, and “Superficial evidence of the presence of groundwater flow systems”. Mexico’s hydrogeological features were produced. The results show that 30% of Mexico is considered to be discharge zones of groundwater flow systems (regional, intermediate, and recharge). Natural recharge processes occur naturally in 57% of the country. This work is the first holistic analysis of groundwater in Mexico carried out at a national–regional scale using only the official information available to the public. These results can be used as the basis for more detailed studies on groundwater and its interaction with the environment, as well as for the development of integrative planning tools to ensure the sustainability of ecosystems and satisfy human needs.

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