and technical provision of the operations."
Prior to the contractual work, geological, geophysical and technological
information on the well is gathered. Based on this information, we work
out recommendations for the coring technology to be applied, equipment,
indication technique, core express-analysis and logging complex for
the particular geological and technical conditions.
addition, the following documents are prepared:
and technical assignment;
regulating the relationship with the Drilling Contractor.
AND MATERIALS DELIVERY TO THE SITE"
days before the work, a field team of our specialists goes to the site
to deliver all necessary equipment and materials including the following:
the coring process:
diamond hard-alloy core drilling bit;
expendable core receivers or containers for core transportation.
core treatment and express-analysis:
machine with a diamond saw;
machine with a diamond crown bit;
geological and chemical laboratory;
for core preservation and express-analysis.
the well site prior to coring and core express-analysis, our specialists
inform the drilling crew of the technical and technological characteristics
of the coring and other special equipment and its safe operation.
scope of our specialists includes the following:
of preparation, assembling and disassembling of core barrels and special
equipment used for low-invasion coring;
and technological monitoring of the coring process, mechanical logging
using a special station of geological-technical control (if it is
available on site);
mud sampling and analysis;
introduction into the water-base mud, regulating their concentration,
extraction from the receiver and placement in the vessels filled with
description of the core;
of complete core sections and preparation of samples and fragments
(cubes and cylinders);
of mud filtrate invasion in the core pore space;
express-analysis providing some data on the reservoir properties and
estimates of pore water salinity;
of selected samples and fragments for storage and transportation;
and video filming of the core samples;
the selected collection of the core samples in plastic barrels;
of the core collection to Tyumen.
STUDIES OF CORE PHYSICAL PROPERTIES"
collection of preserved core samples is studied in detail at the main
Basic set of core studies includes the following:
of samples and fragments;
out cylinders, cubes and fragments;
(cylinders and fragments);
Resistivity determination at initial saturation;
determination for samples saturated completely or partially with a
specific brine solution;
water chemical composition analysis;
filtrate chemical composition analysis;
of the residual water saturation of oil saturated core in retorts;
extract recovery from de-preserved samples (fragments);
of indicator concentration in aqueous extracts, initial water saturation
water total salinity analysis;
and estimate of the reliability of the results obtained;
and physical characteristics of the layers.
At the Client’s request some additional core studies may be performed:
rock description using thin sections, their photographing;
diffraction analysis of clay minerals of the cement;
radioactive components content;
factor and residual oil saturation;
of rock permeability to liquid in situ;
determination of relative permeability;
measurements (semi-permeable membrane method, ultra-centrifuging);
wettability and hydrophoby;
and strength characteristics.
AND INTEGRATED INTERPRETATION OF LOG DATA AND RESULTS OF CORE PETROPHYSICAL
Basic set of studies:
of log materials obtained as per the work program in the interval
of interest of the well:
the field record (LAS-files) from the magnetic tape;
calibration and evaluation of the log quality;
and processing of the core analysis results:
the results in the “Core-database”;
core samples to the depth using log data;
a lithological column using core data, and core graphs of the
major properties (porosity, density, water saturation, permeability,
of the core major properties and drawing appropriate curves:
= f (O, Srw), Rt = f (O, Sw), etc.;
standard curves Fr = f (O), Q = f (Sw) and others;
bar charts for the major reservoir properties;
of the average weighted values of reservoir porosity and water
saturation using core data, evaluation of reservoir Sw reliability;
and interpretation of log data:
a chart of log data in the interval of interest;
a lithological column ;
analysis of the log and core data with the aim of estimating its
quality and justification of the integrated geological interpretation
of the logging materials;
a linear component rock model for the interval of studies, and
a rock pore space model;
of porosity and water saturation of the objects studied.
addition the following analysis may be performed:
of the algorithm for estimating the reserves calculation parameters
of the objects under study using newly obtained information on the
of the methodological and petrophysical provision for estimating reservoir
calculation parameters (oil and gas saturation, porosity, marginal
poroperm values, oil recovery factor, identification of the productive
intervals and net thicknesses);
data processing using coordinated techniques with the aim of reserves
estimating (estimating reservoir parameters and drawing electronic
graphs in accordance with the requirements of the State Commission
on Reserves) for oil pools and fields.
and Geophysical Characteristics and Formation Model in the well section
of the Severnoye Field
"FINAL REPORT PREPARATION AND PRESENTATION"
results of the work on a well are summarized in a report in a hard copy
drawn up in accordance with GOST 7.63-90 “Report on the geological study
of the subsurface. General requirements to the content and form”, and
on a floppy disk. Every report is reviewed and is presented to the Client’s
specialists and experts invited by the Client.
of volumetric water saturation (1),
oil saturation (2)
and bitumen content (3)
in the rocks of the Bazhenov suite interval.
section of the Parfenov and Boklan horizons sediments (East Siberia)
in accordance with the data from SL-GRL-NL
3-less siliceous quartz-type rocks.
of the major rocks and oil-bearing reservoirs of the Bazhenov suite
based on logging set of surveys including gamma-ray density log, gamma-ray
log, neutron log (GRDL-GRL-NL)