We will be holding the traditional December meeting and Christmas social on Thursday 12th December 2024 at our usual venue Kivi in Den Haag.

Geo-Hazard Monitoring and Modelling

Doors will open for registration at 15:30 with the meeting commencing at 16:00.

After the meeting we will have our traditional Christmas social with a delicious and extensive buffet at KIVI.

Attendance is free of charge for DPS members

We host two speakers sharing their expertise on the topic:
Han Claringbould (Geothermal Consultancy Sproule) and Peter A. Fokker (TNO)

Talk 1:
A Pragmatic Approach to Monitoring Induced Seismicity and Subsidence at Geothermal Operations
Speaker: Han Claringbould, Team lead, Geothermal Consultancy Sproule, Voorburg, The Netherlands

Abstract:
Geohazards such as induced seismicity and subsidence are commonly, and often wrongly, associated with geothermal operations. Due to the vastly different types of geothermal plays and variable local geologic conditions, the public perception of risk related to a geothermal system is regularly misinterpreted. The public’s perception of subsurface or mining activities can put a geothermal project’s social license to operate at risk but may not fully account for the conditions that have the greatest impact on geohazards such as geothermal reservoir characteristics (e.g., matrix permeable sands, fractured carbonates, or enhanced/engineered fracture networks) or local geological setting (e.g., tectonically active region, presence of faults).

In the Netherlands, geothermal heat from sand matrix permeable reservoirs has been produced for over a decade. During this time, no geohazards have been associated with geothermal operations producing from sandstone aquifers. One exception was induced micro-seismicity associated with a geothermal project – now closed – operating from a fractured carbonate reservoir. Public perception of geothermal operation has been negatively influenced by activity involving onshore wells and limited seismicity resulting from depleted gas reservoirs in the northern part of the Netherlands. This has led to very conservative regulations for all subsurface mining activities, including geothermal operations. Currently all potential geothermal projects must evaluate the geohazard risk according to a rigid guideline to obtain necessary permits. Furthermore, many projects have to abide by a strict seismic risk protocol that includes a traffic light hazard quantification system to mitigate risk.

Geothermal operators can bring in specialists to set up systems such as local seismic networks to monitor geohazard risk. However, the expense and sensitivity of these services are commonly disproportionate to the actual risk presented by the project. To reduce both the cost of installing a high- resolution monitoring system, and the subsequent operating costs, we have developed a pragmatic solution to monitoring geohazards using publicly available data. Seismic activity is monitored from the national seismic monitoring network (KNMI); subsidence is measured using Interferometric Synthetic Aperture Radar (InSar) data from the ESA Sentinel-A satellite.

Potential geohazards are characterized using Python-based data processing and visualization scripts. These geohazard monitoring tools provide geothermal operators with a cost-efficient solution that aligns with responsible geohazard management. This internationally scalable monitoring approach is currently being deployed at twelve geothermal systems across the Netherlands, providing project operators with effective and transparent geohazard management for government regulators and the public.

Speaker Bio:
Han Claringbould is Team Lead, Geothermal Consultancy and Senior Geoscientist at Sproule. He has expert understanding of low-medium enthalpy geothermal systems, geo-hazard risk assessment and management, and upper-crustal geology. Through his current role, Han: leads Sproule’s geothermal consultancy services, providing tailored strategic and technical advice along the full lifecycle of geothermal assets; conducts technical and economic due diligence of (prospective) geothermal developments; and performs monitoring and analyses of seismic activity and subsidence around geothermal sites.
As a seasoned project manager at Sproule, Han leads and oversees multi-disciplinary projects involving the exploration, realization, and exploitation of geothermal operations in the Netherlands as well as abroad (North and South America, and Europe). He has a deep understanding of the Dutch subsurface geology and geothermal reservoir characteristics of the typical, deep, matrix-permeable sedimentary systems. Moreover, Han is one of the leading experts in geohazards management for geothermal operations in the Netherlands. He developed a seismic monitoring tool that is currently active at the majority of the operating geothermal assets in the Netherlands, has written Seismic Risk Management Plans for many geothermal operations, and, as part of the Geothermie Nederland subsurface working group, develops the guidelines for safe and responsible geohazard management for geothermal.
Prior to Sproule, Han has gained over a decade of experience in exploration and upper-crustal stress and strain development analyses from E&P companies and leading research institutions globally. This includes research into fault characterization and stress evolution at the Earthquake Research Institute of The University of Tokyo, and sedimentation and tectonics at Lamont-Doherty Earth Observatory of Columbia University in New York. He has a B.Sc. Earth Sciences from Utrecht University, a M.Sc.
Geology from Colorado School of Mines, and obtained a Ph.D. Geology from Imperial College London studying upper-crustal stress and strain evolution.

Talk 2:
SRIMA: a fast tool for the assessment of potential induced seismicity and fracturing
Speaker: Peter A. Fokker, Reservoir Geomechanicist ,TNO, Utrecht, The Netherlands

Abstract:
The safe and effective deployment of geothermal energy and storage of carbon dioxide requires an assessment of potential induced seismicity and fracturing through the seal above the reservoir. To aid such assessment we have built the SRIMA tool (Seal and Reservoir Integrity through Mechanical Analysis) and we have made it available online. The tool can be used in the Standard extended Seismic Hazard Analysis, which is part of the seismic hazard and risk assessment for geothermal projects in the Netherlands. SRIMA is a fast semi-analytical tool that provides a scenario-based analysis of pressure and temperature changes around an injection well, the resulting stress changes on nearby faults, reactivated fault area, the maximum credible earthquake magnitude, the resulting PGV distribution and an estimate of damage. SRIMA also computes the potential for development of tensile fracture in the seal and base. SRIMA has been designed to give first-order estimates of these results. All calculations can be performed in a stochastic framework, which allows the assessment of failure probabilities. In this presentation, the physics incorporated in the tool will be briefly presented, and the application will be demonstrated with examples.

Speaker Bio:
Peter Fokker is senior scientist in the Reservoir Geomechanics group in TNO, and a guest researcher at Utrecht University and Politecnico di Torino (Italy). His research interests are related to the sustainable use of the subsurface in the field of geomechanics and reservoir engineering, with a key link to geology and remote sensing. He has worked extensively on coupled models and inverse modelling. Applications include subsidence and seismicity induced by hydrocarbon production, underground storage, and geothermal energy. He holds MSc and PhD degrees in physics from Utrecht University.

Looking forward to seeing you there
DPS Board

You can sign up below, or send a mail to info@dps-nl.org with your name and affiliation.