Appendix 1
To Contract No. ________________
dd. _______________ 2015
GEOLOGICAL ASSIGNMENT
for processing and interpretation of legacy 2D CDP seismic data
Block ЕР-4, the Republic of the Union of Myanmar
1. Work objective, special boundaries and general overview of the study area
1.1. Processing and interpretation of 2D seismic data with the objective to study the geology of
the sedimentary sequence within the south-eastern part of onshore Block ЕР-4, the
Republic of the Union of Myanmar
1.2. The scope of work includes:
- mining, analysis and review of geological, geophysical and other field or production data;
- processing and integrated interpretation of the seismic data;
- preparation of the geological report in compliance with the Customer’s requirements.
1.3. Corner point coordinates of Block ЕР-4:
Corner point
Northing
Easting
##
deg.˚
min.ʹ
sec.ʹʹ
deg.˚
min.ʹ
sec.ʹʹ
A
18
48
30
95
0
0
B
18
48
30
95
12
30
C
18
30
0
95
15
0
D
18
30
0
95
0
0
1.3.2. Point coordinates:
Point
##
deg.˚
Northing
min.ʹ
sec.ʹʹ
deg.˚
Easting
min.ʹ
sec.ʹʹ
1.4 The scope of work is ~200 line km along approximately 14 seismic lines. Subject to the
quality of the data after digitization and assigning of the geometry and configuration to the
vintage field seismic records (seismograms) the scope may be adjusted.
1.5 The main parameters of the field data acquisition – to be provided together with the dataset
for processing and interpretation.
1.6 The vintage surveys are dated from 1980 to 1997.
1
2.1.
2.2.
2.3.
2.4.
2.5.
2.6.
2.7.
2.8.
2.9.
2. Geological objectives, workflow and approaches
Gathering, digitizing and analysis of geological and geophysical information.
Processing of seismic data with modern computer-aided software and technologies.
Seismostratigraphic correlation of the reflectors.
Mapping of the main geological features – time-structure maps (TWT), interval velocities,
depth-structure maps.
Mapping of faults, pinch-out zones and zones of facies changes, erosion surfaces or
unconformities related to the target formations.
Identification of the trends in the evolution of the study area with the help of the
paleostructural analysis based on the main reflectors or seismic events.
Locating zones of reservoir strike based on the comprehensive interpretation of the well
logs and 2D seismic data.
Locating new prospects and leads with HC potential.
Recommendations on prospects ready for deep exploration drilling.
3.
Methodology and scope of work
3.1. Stage of processing:
3.1.1 Calculation of datum statics due to topography (heights) and first break picking.
3.1.2 Geometry and configuration, editing.
3.1.3 Signal filtering
3.1.4 Spherical divergence amplitude correction.
3.1.5 Surface-consistent amplitude correction (equalization).
3.1.6 Velocity analysis.
3.1.7 First iteration of statics correction.
3.1.8 Surface-consistent deconvolution.
3.1.9 Velocity analysis.
3.1.10 Second iteration of statics correction.
3.1.11 Spectral (wavelength) division noise reduction
3.1.12 Velocity analysis.
3.1.13 Normal moveout (NMO) correction
3.1.14 Multiple wave attenuation (subtraction).
3.1.15 Zero-phase spectral signal bleaching.
3.1.16 Third iteration of statics correction.
3.1.17 Seismogram time migration and velocity analysis – two stages.
3.1.18 Final seismogram time migration.
3.1.19 Zero-phase spectral signal bleaching for stacked sections.
3.1.20 Coherence filtering of stacked sections.
3.1.21 Processing sequence is to be considered the main reference and may be subject to
additions and/or changes if agreed by both parties.
3.2 For QC/QA of the initial seismic records and processing the final report shall include the
following items:
3.2.1 Quality assessment of the initial raw (field) seismic records.
3.2.1.1 Color-coded display along 2D lines of S/N ratio in the interval of the target formations
outside of the ground roll cone for every seismogram.
3.2.1.2 Color-coded display along 2D lines of amplitudes in the interval of the target formations
outside of the ground roll cone for every seismogram.
3.2.1.3 Color-coded display along 2D lines of the dominant frequencies in the interval of the
target formations outside of the ground roll cone for every seismogram.
3.2.1.4 Color-coded display along 2D lines of the actual fold for different offsets
2
3.2.2 Quality assessment of seismic data processing
3.2.2.1 Color-coded display along 2D lines of S/N ratio in the interval of the target formations
after each key step in the processing sequence.
3.2.2.2 Color-coded display along 2D lines of the dominant frequencies in the interval of the
target formations after each key step in the processing sequence.
3.2.2.3 Color-coded display along 2D lines of the (spectral) bandwidth in several fixed points in
the survey (spread) after each key step in the processing sequence.
3.3 Stage of interpretation
3.3.1 Basemaps of the study area with available exploration data including seismic
lines/surveys and wells.
3.3.2 Digitization of well logs for three deep wells located within the study area.
3.3.3 Well log correlation based on the stratigraphic sequences and main target formations.
Correlation panels and schemes.
3.3.4 Seismostratigraphic correlation of the main reflectors.
3.3.5 Detecting faults. Identification of possible pinch-out zones, facies changes or erosion
features.
3.3.6 Time structural maps for the main reflectors: (the list of the reflectors to be provided by
the Customer).
3.3.7 Selection of the depth-velocity model. Mapping interval and average velocities.
3.3.8 Depth-structure maps for the main and target reflectors and near top of the potential
reservoir units (the list to be provided by the Customer).
3.3.9 Estimated accuracy of the depth maps. Analysis of depth mapping including comparative
study of the resulting maps with the maps from the previous years.
3.3.10 Paleostructural analysis for the main reflectors – identification of regional trends in the
geological evolution of the study area. Isopach triangles and maps.
3.3.11 Locating new prospects and leads. Recommendations on prospects ready for deep
exploration drilling.
3.3.12 C3 Russian category resources evaluation for all the potential targets located within the
Block boundaries regardless of their exploration maturity, relevant documentation with
description (passports) for the drill-ready prospects.
3.3.13 The task for interpretation is to be considered the main reference and may be subject to
changes if agreed by both parties.
4. Reporting and deliverables
4.1. The Contractor submits to the Customer End-of-Stage report and a Weekly Progress Report
on the status of processing and interpretation work in the stated and agreed format.
4.2. The main result of the work is the «Report on the Results», which includes inter alia the
Chapter «Methods and techniques of the field data acquisition» (alongside with the
recommendations on refining and adaptation)
The graphics in the report shall include the attachments listed in items 3.2.1, 3.2.2,
vertical time sections along 2D lines, time structure maps, depth structure maps, estimated
parameter maps. All the maps shall display the boundaries of Block EP-4. The scale for all the
produced maps shall be set by the Customer. All the maps shall include the scale details.
4.3. The Contractor shall submit the relevant documentation (passports) for the drill-ready
prospects.
4.4. The Customer shall receive the following data as soft copies (electronic format): to be
provided according to the following requirements and procedures:
- stacked time sections migrated on the seismograms, prior to migration as SEGY;
- datum topographic (heights) corrections, weathered (low-velocity) section, shallowest reflector
and residual statics calculated during adjustment and correction procedures (as ASCII);
3
- stacking velocities (ASCII, SEGY), final migration velocity files as ASCII and SEGY along 2D
lines;
- common depth point coordinates for all the lines, SPS-files in the main reference coordinate
system;
- stratigraphic reference for wells (tops) (as Microsoft Excel);
- acoustic impedance sections (SEGY);
- seismic attributes sections as calculated during the processing sequence (SEGY);
- correlation results for the main reflectors (ASCII, as ХYZ);
- time structure maps for the target reflectors (ASCII, as XYZ);
- interval (average) velocity maps (ASCII, as ХYZ);
- depth structure maps for the target reflectors (ASCII, as ХYZ);
- depth structure maps near tops of the potential hydrocarbon bearing reservoir units (ASCII, as
ХYZ);
- results of the paleostructural analysis (isopach triangle);
- seismogeological cross-sections in the line of the key wells;
- geological cross-sections in the line of the same key wells as above;
- distribution maps for the informative or applicable seismic attributes including amplitudes,
interval travel time, interval thickness, impedance (ASCII, as ХYZ);
- gross, net and pay thickness maps for the main reservoir units (ASCII, as ХYZ);
- development patterns for different types of reservoirs mapped on the results of the
comprehensive integrated interpretation of the dynamic component and velocity analysis of the
seismic data and wireline well log data (as Corel Draw);
- text of the report (as .doc) and all the related graphics to be provided as vector format and
images (Сorel Draw, and JPEG).
All the indicated materials shall be submitted as hard copies and electronic copies on
suitable magnetic media (DVD disks) for archiving.
4.5. The passports for the drill-ready prospects shall be submitted as hard and soft copies.
On behalf of the Customer:
On behalf of the Contractor:
4