1. Detailed Reservoir Description
Reservoir description is an essential technology throughout every stage of field development. It builds on detailed division of stratigraphic framework and focuses on accurate depiction of spatial distribution of reservoir, effective reservoir property, as well as reservoir fluids. The end product of reservoir description is represented in a geological model that effectively depicts the complexity and static and dynamic behavior of subsurface for reservoir management. A good reservoir description project must integrate all available geophysical, geological and dynamic data and information, including seismic, well log, core description and analysis, well test, and production. The key components of reservoir description project provided by LandOcean include the following:
- Fine stratigraphic division of a variety of reservoir types (carbonate and clastic reservoirs) based on high resolution sequence stratigraphic analysis as well as lithologic division of volcanic and other types of non-sedimentary reservoirs;
- Fine structure interpretation based on integration of well and 3 D seismic data;
- Sedimentary facies and/or lithofacies analysis based on log and seismic facies;
- Characterization of reservoir property based on seismic attributes, pre-stack elastic inversion and post-stack acoustic inversion;
- Description of spatial distribution and density of fracture based on anisotropic characteristics of seismic data;
- Analysis of reservoir performance based on integration of static and dynamic production data;
- Construction of a detailed facies-controlled 3D geological model of reservoir based all the above studies; and
- Calculation of OOIP and uncertainty analysis.
Our competitive and technical advantages are the application of series of proprietary seismic-based reservoir characterization technology (with intellectual rights and patents) and many years of experience in complex geological settings in China and abroad. These advantages enable LandOcean to shine in the areas of integrated interpretation using well and seismic data; construction of sedimentary facies and prediction of reservoir distribution in oil and gas fields with complex geology; and sculpting and depicting fracture and cave systems in carbonate strata with the application of specialized proprietary technology.
2. Reservoir performance analysis
Using numerical simulation and conventional reservoir engineering analysis methods, the evolution and controlling factors for pressure and oil and liquid rates are analyzed based on static and performance data of wells. Furthermore, studies are conducted on division of reservoir unit, decline curve analysis of production well, rate and timing of water and/or gas breakthrough, bottom water coning, suitability injection-production system, degree of proved developed reserves vs. proved undeveloped reserves, distribution of bypassed oil and its controlling factors, calibration of reserves and etc., which provide the basis for field development plan (FDP) and adjustment as well as increase of recovery factor for mature oil and gas fields.
Special technology is reservoir performance analysis for heavy oil, fractured and condensate reservoirs.
3. Field Development Plan
- FDP for conventional reservoir
According to the reservoir characteristics, the most effective development method and most suitable well spacing and well pattern are proposed to ensure effective control on water-oil ratio and gas-oil ratio during the development, while achieving the highest recovery factor and maximum economic benefits.
- FDP design for heavy oil reservoir
For ordinary heavy oil reservoir and ultra heavy oil reservoir, reasonable steam inject time, steam injection rate, steam injection pressure, steam injection dryness, steam injection intensity, etc are optimized.
- FDP design for fractured reservoir
Based on the dual permeability character of fractured reservoir (low matrix permeability and high fractured permeability), well types are optimized, reasonable allocation of well spacing and well pattern with association of fractures occurrence are studied.
- FDP design for gas reservoir
According to types and drive mechanism of gas reservoir, reasonable well pattern, production test, choke and productivity estimation, gas transient well testing and gas reservoir numerical simulation are confirmed, and reasonable gas production rate and gas reservoir edge and/or bottom water control plan are proposed.
4. FDP Adjustment
According to structure, reservoir distribution, reservoir physical property, fluid property, fluid distribution and production characteristics, adjustment wells are deployed, and new development plan for mature oil field is reconstructed for the purpose of improving oil and gas field recovery.
5. Reservoir Development Technical and Economic Policy Limit
Through sensitivity analysis of economic parameters for reservoir development, reasonable development method, well spacing, well pattern, reasonable liquid and oil recovery rate, reasonable formation pressure maintenance, reasonable flowing pressure and reasonable production system are determined for the targeted reservoir. Reasonable oil-gas ratio, limit oil-gas ratio, reasonable cycle oil yield, limit cycle oil yield, limit abandoned oil yield, etc for heavy oil steam soaking are examined and proposed.