Today VEGA LLC has a huge number of various geophysical equipment. The Сompany conducts geophysical surveys within the framework of commercial and scientific research, including field geological exploration in harsh conditions inaccessible regions of the country and abroad.
Geothermal research.
Discovery of new geothermal deposits.
The resources of geothermal energy of the Earth are 10 times higher than the potential of hydrocarbon industry.
Geothermal deposits are currently discovered in 80 countries around the world, 58 of them actively use the energy of the Earth’s interior. The share of geothermal energy resources used may be significantly higher, while the environmental situation will improve and the consumption of expensive hydrocarbon raw materials will decrease. These arguments allow us to highly assess the urgency of intensifying the search for new and research of already known geothermal deposits on any continent.
Since the middle of the last century, the main regions in Russian Federation where geothermal energy has developed have been Kamchatka, the Kuril Islands, and Primorsky Krai. Currently, two geothermal power plants in Kamchatka generate approximately 60 megawatts of electricity.
Exploration of the Verkhne-Mutnovsky and Mutnovsky fields, on which these stations are based, was carried out using electrical exploration methods: magnetotelluric and audio-magnetotelluric sounding (MT and AMT). In addition, our specialists performed electromagnetic sounding on Hengil volcano in Iceland, in the mountain systems of Italy, on Reunion Island in the Indian Ocean, in the south-east of Armenia and in states of Nevada and Montana of USA.
An example of a joint study of geothermal sources in the United States, Nevada. 2008-2009 years.
In 2008 – 2009, VEGA LLC jointly with Dewhurst Group LLC performed field work to clarify the position and estimate the resources of geothermal deposits in a number of states of USA.
Based on the results of the work, at a depth of 400-700 m an obliquely lying low-resistance horizon was identified. It is a single body with a mouth coming to the surface in the form of a hydrothermal source.
On the volume model based on AMT data, the low-resistivity object at depths of 400-700 m has a significant distribution, while the near-surface object is localized.
Taking into account the absence of overlap within the exit to the surface of a high-lying low-resistance object, it should appear on the surface as a source.
If there is no source or connection between objects, a deep-lying low-resistivity object is of particular interest for searching for thermal waters.
A brief algorithm for conducting electrical exploration in the search for geothermal objects
Based on the experience of exploration of geothermal deposits performed with high efficiency, we can suggest the following sequence of application of electrical exploration methods of magnetotelluric and audio magnetotelluric sounding.
The first stage is carrying out works using the MT and AMT methods based on the regional profile. The result should be the construction of a geoelectric sectiona, reflecting the presence of an abnormally low-resistance horizon in the interval of the studied depths.
At the second stage of conducting AMT and MT sensing in the area version, maps of the total longitudinal conductivity are drawn with the allocation of anomalous conduction sections in the plan.
At the third stage, the anomalous sections are detailed and a field model is built with recommendations for drilling operations.
Experience in applying non-seismic geophysical and geochemical methods to solve problems of zonal and local oil and gas bearing capacity.
For more than 15 years, VEGA LLC (Eastern European Geophysical Association) has been performing reprocessing and reinterpretation of geological and geophysical data (gravimetry, magnetometry, seismics, etc.) in order to identify promising oil and gas zones within large license areas.
Example of performing geophysical and geochemical works at the Vostochno-Messoyakhsky and Zapadno-Messoyakhsky license areas.
Data processing included evaluating the law of concentration distribution, standardizing the hydrocarbon content in the samples, and producing maps of the distribution of these contents over the work site.
For each type of hydrocarbon’s element detected in the samples, it has been checked whether the concentration distribution corresponded to a normal or lognormal law.
According to the Instructions for Geochemical Prospecting Methods, sets of concentration values or physical and chemical properties for which the Kolmogorov criterion does not exceed 135% are considered to satisfy the normal law.
At the preliminary stage, the quality and completeness of available materials are evaluated, and if necessary, digitization and mapping are performed using potential methods. In each specific case, the data of the most reliable and large-scale surveys are taken as a basis.
In the practice of VEGA LLC, work on the reprocessing and reinterpretation of geological and geophysical data followed by a complex of ground-based geophysical and geochemical works was carried out in the Timan-Pechersk NGO (Nenets Autonomous District), on the northern slope of the Caspian Depression (Volgograd Region), on the territory of the Kuri Depression (MOGHAN block, northern Iran), on the Messoyakhsky Shaft (Yamalo-Nenets Autonomous District).
Reinterpretation of geological and geophysical materials of the Timan-Pechora province (Denisovsky district).
According to the subsurface user, the huge territory of the Denisovsky mining district was not very promising and there was a question of passing a search license. Due to the implementation of a comprehensive reinterpretation of the materials of previous studies and conducting a complex of field work, the high prospects of district were justified and the question of passing a license was removed.
Block diagram of the Denisovsky district based on seismic data
Scheme for comparing the results of interpretation of airborne survey (AMS) data and gravimetric studies
Effective map of promising sites in Denisovsky district and adjacent territories
Reinterpretation of geological and geophysical data from the Moghan block (MOGHAN, Northwest Iran).
Transformation of potential fields
Potential field transformations, factor and cluster analyses were performed to study the geological and geophysical structure of the basement and sedimentary cover.
Mapping of oil-bearing elements of the sedimentary cover
According to the gravity survey data, positive structures of the second order (megaanticlines) controlled by long-lived tectonic disturbances are identified.
Hydrocarbon deposits and known local structures are confined to the designated megaanticlines.
The identified megaanticlinesare promising areas for detecting hydrocarbon traps.
Mapping megaanticlines based on gravity survey data
Mapping megaanticlines based on gravity survey data
Mapping of long-lived tectonic disturbances based on magnetic survey data
Geophysical signs of oil and gas bearing capacity
Distribution of pseudodensity of productive deposits
Map of spectral-amplitude characteristics of the magnetic field
Distribution of pseudomagnetization of productive deposits
Identifying areas of most potential for oil and gas
Scheme of zonal and local forecast of oil and gas bearing capacity of the MOGHAN block. Based on the results of these works, the Iranian National Oil Company allocated license areas and transferred them to the Cients
Determination of the well location at the Bayandysskaya structure (Denisovsky district)
Regions of anomalous values of geochemical elements (according to geoelectrochemistry data)
Areas promising for HC detection based on electrical exploration data
Zones of epigenetically altered rocks
Seismic geological model (based on seismic data)
Magnetic anomaly map
Corresponding anomaly in Gravity field
Based on a comprehensive analysis of geological and geophysical data, 2 deep wells were drilled in the northern and southern domes of the Bayandys structure and commercial oil inflows were obtained from organogenic-clastic limestones of the Upper Devonian.
Forecast of oil and gas bearing capacity based on geochemical data (passive adsorption method) in the Vostochno-Messoyakhsky and Zapadno-Messoyakhsky license areas
Allocation of sites for conducting field geophysical and geochemical (passive adsorption method) works in 2012-2015
- Areas of reduced pseudo-density values
- Axes of zones of increased fracturing (gravity exploration)
- Zones of epigenetically altered rocks (magnetic exploration)
Areas for conducting field geochemical work
Technique of data collection (method of passive adsorption)
Sorber (gas accumulation device) is installed in the soil for 17-21 days
The principle of data interpretation by the passive adsorption method
Typically, 15 observation points at least are required to obtain a reliable characteristic of the reference well.
At the Messoyakha field, the use of 10-12 reference wells in the interpretation of geochemical data is empirically justified.
- Empty well
- Uncovered gas well
- Uncovered oil well
Location of soil gas sampling
Oil
Gas
Absence of hydrocarbons
Typically, 15 observation points at least are required to obtain a reliable characteristic of the reference well.
At the Messoyakha field, the use of 10-12 reference wells in the interpretation of geochemical data is empirically justified.
Geochemical survey in 2012
Allocation of sites promising for HC detection in 2012
Confirmation of the forecast based on geophysical and geochemical data (from the presentation of the Gazprom Neft LLC, 2012).
- Scheme of interpretation of geophysical and geochemical data
- Map of abnormal concentrations of trans -1.2 dimethylcyclopentane
- Map of abnormal concentrations of ethylbenzene
- Map of abnormal concentrations of dvamethylheptan
- Structural map for OG G (2D – 2010)
- Structural map for OG G (7 cube, 2013)
Results of geochemical studies in 2012:
- Wells No. 37 and No. 205 were drilled after geochemical studies. The prospects of the selected sections in the PK1-3 formations (well 37 had gas inflow of Q = 33,000 m3/day) and in the Mx1 formations (well 205 had oil inflow of Q = 31 m3/day) was confirmed.
- According to geochemical and electrical exploration data, promising areas were identified in the junction zone of the Vostochnaja-Messoyakha and Zapadnaja-Messoyakha fields. A positive forecast is given for project wells No. 206, 208,213,216, and 217.
- The elevated 2D seismic block in the area of project well No. 203 is not promising according to geochemical data. After the 3D seismic survey, the corrected structural plan confirmed the validity of the geochemical data.
- It was recommended to perform a complex of geochemical, gravimetric and electrical exploration survey for the prospective site No. 6 in the area of the drilled well No.77. Geochemical survey was performed in 2014 only.
Geochemical survey in 2013
Chart of survey in 2013
– project wells
– drilled wells
– studied wells
– geochemical sorber’s deployment points
The purpose of the survey is to forecast hydrocarbon deposits in the area of wells No. 158 and 108.
Results of survey prospective area in 2013
- Areas of the most stable anomalous of geochemical data values
- Contours of sites promising for the detection of hydrocarbon accumulations
- Geochemical indicator of the presence of hydrocarbons:
- positive
- negative
Hexadecane – group of normal alkanes
Limonene – group of biogenic compounds
IV HC
Methylnaphthaline – group of aromatic hydrocarbons
p_Cumo l – group of aromatic hydrocarbons
The sum of the indicator elements of the aromatic hydrocarbons group
Forecast results:
- Geochemical criteria for the prospects of the studied area on HC are determined;
- Determined areas that are promising for detecting hydrocarbon accumulations.
- Based on a comparative analysis of geochemical data, the prospects of project wells No. 158VM and 108VM are estimated:
- Well No. 158 is located on the periphery of the prospective site and is not characterized by industrial saturation (confirmed by drilling immediately after completion in 2013).
- Well No. 108 is highly promising for commercial gas condensate inflow, similar to well No. 51 (as a result of drilling in 2014, oil-saturated sandstones were discovered in the BU16 formation)
The full cycle of work from the beginning of the field stage to the protection of the report took 3 months.
Geochemical survey in 2014.
Passive adsorption method. The scheme of geochemical testing in 2014.
- testing with 500 meters spacing between observation points
- testing with1000 meters spacing between observation points
- absent geochemical data
- tested wells
The purpose of survey:
- forecasting of hydrocarbon deposits on the studied area
- update position of the project wells 116 and 118
Scope of work:
- 165 sorbers were deployed as reference around 10 wells and 1 project well
- 594 sorbers were deployed along survey profiles
Repeatability of the results of geochemical testing on reference wells.
Unproductive well (used all defined UV elements)
Repeatability of the results of geochemical testing on reference wells.
Productive well (used all defined UV elements)
Comparison of data on productive and unproductive wells. The ratio of the content of the elements.
The level of HC components in the design sle.118 is significantly lower than in the highly productive well #73 (used all defined HC elements).
- Well #73/104
- Well #118/104
The level of HC components in the project well #118 is lower than in the nearest productive well #77 (used all certain elements).
- Well #77/104
- Well #118/104
The content of HC components in the design well #118 is significantly lower than the average content in 7 reference productive wells (used all certain elements).
- 7p/3unpr
- 118p/3unpr
Forecasting of deposits in 2014. Gamma logging method.
Results of geochemical survey at the Vostochnaja-Messoyakha and Zapadnaja-Messoyakha in 2012-2014
- Comparability of results on reference wells tested in different field seasons is noted, which increases the reliability of the forecast.
- The identified indicative elements (2014) largely coincide with the indicative elements identified in previous studies (2012-2013);
- Project well # 118, according to geochemical testing, is located in an unfavorable zone, and the lay out point needs to be shifted;
- The observation density at project well # 116 is insufficient for reliable conclusions about its productivity.
- Geochemical anomalies that are promising for the detection of hydrocarbons are identified in the studied area