Microseismic monitoring
Microseismic monitoring of oil & gas fields comprises of network of microseismic stations, main purpose of which is the detection and registration of very small level seismic events on the territory of oil & gas fields and mines, with further deep processing of seismic results and analysis of natural and induced seismicity. Microseismic monitoring service is provided by Zhanazhol Munai Service LLP on the basis of:
- high-tech solutions in the hardware and software segment;
- equipment for recording microseismic events;
- special software for processing recorded information.
Competent interpretation of the results is the key to an effective response to possible risks associated with the consequences of induced seismicity
Microseismic monitoring helps to reduce the risk of industrial hazards, therefore, networks of continuous long-term observations stations on certain territories and information processing centers are being created to process the results in real-time and conduct analysis.
Currently, monitoring includes registration, further processing and interpretation of seismological data, based on the results of which are interpretations and forecasts are made. Monitoring is also divided according to the size of the monitoring area covered into: world — to assess the full picture of the planet, regional — to monitor a specific region and local — for a specific site (e.g. oil & gas, mines, etc.).
The applied tasks of this direction are considered to be the study of regional/local seismic activity of a certain territory or local area. They can be areas of nuclear power plants, hydroelectric power plants, oil and gas fields, mines, open pits, etc.
Seismic monitoring is an integral part of the production work of oil and gas companies, which is reflected in the requirements of the Code of the Republic of Kazakhstan No. 125-VI "On Subsurface and Subsurface use" dated December 27, 2017.
Microseismic monitoring allows:
- to automatically detect and locate even very weak seismic events;
- to determine the mechanism of the focus of events.
Together, this makes it possible to study the dynamics of tectonic faults of the Earth.
Thanks to the available means of communication, it is possible to promptly notify officials of ongoing earthquakes and other seismic events, as well as timely response to such situations.
- Station's digital data is linked to a single time using a GPS receiver with an accuracy of at least 1 microsecond and transmitted to the information processing center using a satellite channel;
- Following activities are carried out at the center: the formation of a primary archive of continuous seismograms, automatic detection of signals potentially associated with seismic events, and subsequent processing of these data by a seismologist interpreter.
General data transmission scheme is shown in the figure.
Obtained results allow customers of Zhanazhol Munai Service LLP to assess the full picture of the seismic regime and establish a high level of information support.
Safety systems for essential structures such as nuclear and hydro power plants, oil and gas wells, mines, bridges and other facilities are not capable of operating at full capacity without microseismic monitoring. Countries of the European Union and many other countries of the world practice exactly such policy. At the same time, it is not taken into account whether the region or the territory where an important industrial object is located is earthquake-prone.
Development of the energy sector industry require microseismic monitoring of those areas of the earth's crust where energy facilities are located.
Real-time seismic monitoring is carried out through a network of seismic stations that are evenly distributed over the area under study or use existing stations covering the desired area.
Having identified seismic sources, their parameters are determined: the time in the hearth, the coordinates of the epicenter, the depth of the hypocenter and the magnitude. Next, instrumental data on modern earthquakes are used, which, when combined with information about historical earthquakes, allow for seismic zoning.
It is possible to outline seismogenic zones and assess the seismic risks of the territory on the basis of:
- estimates of seismic activity parameters and maximum magnitude.
- estimates of the parameters of the source mechanism and the type of displacement along faults (discharges, surges and shifts).
Automatic detection of seismic events
Automatic seismological centers perform an important and most difficult task:
- promptly adjust the maps of tectonic activity of the region, make adjustments to the maps of score and concussion;
- having received an automatic notification from the monitoring system, they take emergency measures and carry out operational measures depending on the emerging seismic situation and risks;
- form a database of seismological data, fill them with continuous forms of tectonic activity processes, fill out bulletins of seismic events, and also work with other accompanying information;
- exchange information with other seismic stations and networks, collecting data;
- use the general information coming from all automatic seismic stations to improve the location of seismic events and the ability to assess their parameters.
It is possible to work effectively in real time only with the introduction of highly developed hardware and mathematical software, and it is precisely such equipment and software that the staff of Zhanazhol Munai Service LLP use.
Why is microseismic monitoring important?
- identification of active faults in oil and gas fields, in the territories of nuclear power plants, hydroelectric power plants, mines, etc.;
- obtaining a huge amount of important information for assessing the danger of earthquakes;
- the ability to establish the initial level of natural seismicity before the start of work on injecting gases, wastes, water, etc. into underground formations;
- obtaining early warning of major events related to injection operations to maintain reservoir pressures;
- use to characterize stresses in the formations during underground work.
To achieve these goals, advanced processing of recorded seismicity is critical.
- protection of the population of local territories in emergency situations — strong earthquakes;
- oil & gas field operating;
- operation of water reservoirs, as well as thermal springs;
- operation of nuclear power plants, thermal power plants, hydroelectric power plants, state regional power plant.
Tectonic earthquakes are commonplace in places where elastic deformation energy accumulates. In these places, cracks begin to spread along the entire plane of the fault.
- only 10% of the total energy is released in the form of seismic energy;
- the remaining 90% are used to deepen and grow earthquake cracks or are converted into heat, which is released during friction.
design of the monitoring system;
analysis of seismological conditions at observation points;
selection of recording equipment.
installation of equipment at the test site or the observed territory;
organization of telemetry.
deployment of an automated information system for collecting, processing, storing and analyzing seismological data;
adaptation of the information system to the conditions of the observed territory;
integration of information system interfaces into the customer's infrastructure.
launch of a monitoring system, processes for collecting, registering and analyzing registered information;
formation of information messages (urgent notifications, operational summaries, bulletins, catalogs, reports);
technological support of the project.
Experience of "Zhanazhol Munai Service" LLP in the provision of microseismic monitoring services:
since 2016
continuous monitoring of the seismic state of Zhanazhol, Kenkiyak, Sev. Truva fields
since 2019
continuous monitoring of the north-eastern part of the Caspian Sea on local and regional seismic events
Republic of Kazakhstan, Aktobe, Tauelsizdik ave., 5 k. 1, office 45