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Helium survey—identification of “sweet spots”
locations for exploratory, appraisal and production drilling
November, 2009
Executive summary
• During exploration, appraisal and development of oil and gas fields with complex geology, such as fracturing
permeability, low continuity of thickness and porosity formations, energy companies face an ever present
problem of low drilling success.
• Traditional exploration technologies such as seismic do not always accurately predict hydrocarbons
saturation.
• In a review of more than 2600 US and international wildcat wells – all drilled after completion of
geochemical or non-seismic hydrocarbon detection surveys- more than 80% of wells drilled on prospects
associated with positive hydrocarbon anomalies resulted in commercial discoveries; and only 11% of wells
drilled on prospects not associated with such anomalies resulted in discoveries*.
• Actual Geology can identify an active petroleum system in the exploration area, generate unique nonseismic leads for further geological and seismic evaluation and identify “sweet spots”.
• Our methods are non-invasive and have a minimal environmental impact.
* presentation at 2008 AAPG International Conference and Exhibition, Cape Town, South Africa, October 26-29, 2008
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Outstanding track record
• 50 completed projects covering over 30,000 sq km in the last 8 years
• Strong in-house analytical team interpreting helium survey results for clients
• Clients: Gazprom, Rosneft, Lukoil, Yukos, Norilsk Nickel and many others.
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Our services
• Actual Geology services fit well into an integrated exploration strategy by detecting occurrences of
hydrocarbons’ by-products, such as helium, which serve as indicators to the location of undiscovered oil and
gas accumulations.
• Actual Geology provides:
− Mapping of helium concentration and subsequent forecasting of reservoir properties.
− Prediction of section saturation before drilling.
− Determination of areas with improved fractured permeability in prospective reservoirs or producing
deposits.
− Prediction of reservoir distribution, delineation of oil and gas accumulations.
− Determination of residual reserves at mature fields with declining production.
− Identification of prospective drilling targets, cut off of the low prospects and high risk zones.
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Helium survey
Service
Helium survey
Data acquisition method
Field measurements of
helium concentration at
1-1.5 m below earth surface
and in near-surface air.
Scale
1:50000; 1:25000; 1:10000
(100x100m up to 25X25m
grid)
Helium survey at
well heads of
producing wells
Measurements of helium
concentrations at well heads
Benefits
1. Prediction of section saturation before drilling
2. Delineation of areas with better reservoir properties
3. Prediction of fracturing in reservoirs and producing
interval
4. Identification of “sweet spots” for drilling
1. Identification and delineation of active reserves
2. Forecast of reservoir performance
3. Monitoring of well performance, recommendations
for well work over
4. Determination of residual reserves at mature fields
5. Identification of prospective zones for further
completion
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The process
Preliminary stage(field):
Helium survey
300x300m grid,
or 100x100m grid
Data processing
Preliminary data
interpretation
Stage one(field):
Helium survey
100x100m grid,
or 25x25m grid
Identification of
helium anomalies
Stage two: (analytical)
Data processing
Data interpretation
Final mapping
of helium anomalies
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Timeframe
• Once equipment and the team (20 detectors and 50 field specialists) are on site an average survey
duration over an area of 100 km² is 60 days including:
− Deployment and deconstruction of field camp, testing of field equipment – 5 days
− Helium measurements on 100х100 m grid – 14 days
− Preliminary field data processing and planning of detailed grid – 4 days
− Helium measurements on detailed grid (15% of total area) – 7 days
− Final data processing and interpretation of the results –25 days
− Contingency work (10%) - 5 days
• Production rate of one team – 30-40 sampling points per day
Equipment example: PHD-4 Portable Helium Detector
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Field work logistics
1. Equipment and tools:
• Helium leak detectors and gas analyzers
• Computers and specially designed/developed
software for operational in-field quality control
and processing
• Satellite communications between detectors
and server holding central database minimizes
human intervention and possible errors
• GPS- enabled equipment for accurate
positioning and recording
2. Locally purchased (rented) equipment:
• Cross-country vehicles
• Field equipment (sleepers, office, kitchen,
generator, etc.)
• Water, food and fuel supply tracks
3. Personnel
• Initially – qualified Actual Geology specialists
• Support personnel– locally hired
• Future development – recruitment and training
of local staff
Mobile laboratory (a) and field equipment (b) versions
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Final results: Cheriomykhovskoye oilfield
Well #
(heavy, high-viscosity oil)
161
5479
824
5528, 5481, 5473
Helium anomaly
Daily production rate
Bbl/day
positive
positive
positive
negative
64
64
64
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Final results: Galianovskoye oilfield
Well #
Helium anomaly
Daily production rate
Bbl/day
2034
2035
39
2024
positive
positive
positive
negative
70
235
262
dry hole
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Final results: Aprelskoye oilfield
Well #
Helium anomaly
Daily production rate
Bbl/day
6
5
positive
negative
164
dry hole
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Final results: Sredne-Shapshinskoe oilfield
Well #
Helium anomaly
Daily production rate
Bbl/day
7000
7002
positive
negative
300
<35
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Theoretical foundations
• All petroleum basin exhibit surface or near-surface hydrocarbon gases leakage.
• Helium on Earth is mostly created by the natural radioactive decay of heavy radioactive elements (thorium and uranium).
• Helium is a noble gas, chemically inert and is nonabsorbent into surrounding rocks and doesn’t form compounds. Helium’s
ability for migration is greater than of other gases, with the exception of hydrogen.
• Helium migrates along the tectonic faults and through high-fractured zone. Seals, such as clay rocks, are not an obstacle for
helium migration. Increased concentrations of helium in the near surface zone are the projections of zones with higher helium
gas-saturation and improved permeability of geological section.
• The average helium concentrations are: 0.65 ml/l - in bottom water of hydrocarbon accumulations; 7 ml/l - in oil pools; 100 ml/l
- in gas pools (ml/l – milliliters per liter).
Helium concentration - residual oil saturation relationship
Oil saturation
Helium concentration
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Theoretical foundations
Different vertical sections of helium concentration in the case of presence(b) or absence(a) of hydrocarbon
accumulations within sedimentary cover.
As helium solubility is so much greater in hydrocarbon pools than in water, reservoir is saturated by helium
and it’s concentration increases (Fig.1, b). Near-earth surface helium concentrations is greater in case of
hydrocarbon pool presence in geological section (b) in comparison with case where pool is absent (a).
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Conclusions
• The results of helium surveying leads to significantly better prediction, therefore risk and cost reduction
• Helium surveying is a powerful complement to conventional exploration methods.
• Further integration with available seismic, logging and production data can help companies to identify
residual reserves, enhance potential of declining production or flooded fields, better plan drilling operations
(especially horizontal wells) during exploration, appraisal and development stages
• In order to assess and prove effectiveness of its methods Actual Geology can conduct a pilot survey on an
already explored field where a number of wells have been drilled in order to compare helium survey results
with company’s existing information
• Helium surveying is a reliable and proven (by a number of successful projects in various geological settings)
technique for accurate identification of the best drilling locations. Our experienced specialists are able to
work in practically any complex terrain, traditionally off-limits due to restricted accessibility
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Contacts
London
St Petersburg
Maxim Golodnitsky
Viktor Chistiakov
Project Manager
General Director
Suite 3, Barkat House
36 Rubinstein street, office 35,
116-118 Finchley Road
St. Petersburg
London, England NW3 5HT
191002 Russia
Tel. +44 (0)20 7433 2512
Tel. +7 (812) 347 78 19
Fax. +44 (0)20 7692 7957
Fax. +7(812) 571 83 98
E-mail: [email protected]
E-mail: [email protected]
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