Infill Offset Well relationship (Parent-Child Well), vertical and horizontal interference in Permian:
NITEC investigated the inference impact on well performance and parent-child relationship for a major oil company. Well spacing per section was optimized based on the injected frac volume. The optimum time to introduce the child well after parent production, minimum vertical and horizontal distance from the parent well to minimize the parent’s influence on the child well production were determined. All the optimization was based on a calibrated (history matched) seven (7) well physics-based simulation model in Permian.
Huff and Puff Feasibility in Eagle Ford:
Based on an eight (8) well calibrated simulation model in Eagle Ford, feasibility of huff and puff gas injection for a full field development was investigated. The actual gas injection pilot project was part of the calibration process. The performance under different operational scenarios including injection rates, injection/production sequence, and scheduling were investigated and reported to support the management’s decision.
Frac. size vs. Spacing optimization in Permian:
NITEC’s client needed proper optimization for well spacing and frac size. Through a 6 well simulation model, NITEC provided the optimum spacing and frac size for different benches of the producing formations. Optimum frac sizes and spacing were different for different benches. The client increased capital efficiency by differentiating the completion and spacing practices among the different benches.
Refacing Evaluation in Eagle Ford:
NITEC’s client needed decision support on deciding between refacing existing wells and drilling infill wells in the same area. NITEC provided analysis of both options by utilizing a five well simulation model that is calibrated for reservoir and geomechanical parameters in the area.
Unified EOS generation for Woodford:
A unified EOS model was generated for Woodford shale using 20 samples covering from dry gas to gas condensate.
Well Spacing optimization in Bakken and Three Forks:
NITEC’s client needed an evaluation of different spacing in Bakken and Three Forks development for exploration purposes. Using publicly available data around the exploratory acreage a representative simulation model was calibrated for reservoir and geomechanical parameters. This information was migrated to the exploratory area by changing the reservoir characterization accordingly. Further sensitivities to optimize spacing and landing for this new area were performed.
GOR vs. water production relationship in Permian:
NITEC’s client needed evaluation on the relationship between GOR behavior and water production and water saturation in Permian. NITEC explained the relationship between water saturation, wettability, and GOR through modeling. This knowledge impacted the understanding of the reserves and long term production behavior.
Completion optimization in Eagle Ford:
NITEC’s client needed to improve its completion practices to recover more oil in Eagle Ford. Simulation study led to a design that improved the Infill of an infill well performance such that the new well produced more than the original parent well’s total production within months. The optimization was based on a 4 well history matched simulation model.
Compressor design criteria based on gas injection performance in Eagle Ford:
NITEC’s client needed guidelines to build proper size compressors to be utilized in huff and puff operations at Eagle Ford. Using models created at different depths containing different oil types, operational ranges (pressure and injection rate) of possible huff and puff operations were determined for proper compressor design.
A quick study to evaluate the potential of a field in Permian for acquisition:
NITEC’s client needed a quick evaluation of a field that they were planning to bid on. They used NITEC’s model to understand and evaluate the upside potential by infill drilling and assess the uncertainties associated with the project. The analysis provided by NITEC helped the client’s decision to bid or not on the prospect.
Frac size vs. Spacing optimization in Permian:
NITEC’s client needed proper optimization for well spacing and frac size. Through modeling, NITEC provided the optimum spacing and frac size for different benches of the producing formations. Three reservoir simulation models were generated to create an optimum solution that would represent multiple regions in the area. Improved understanding of the reservoir and the spacing optimization that takes into account the interference supported the client’s decision making on capital spending.
Huff and Puff Pilot Design:
Based on a nine (9) well history matched the model in Eagle Ford, the feasibility of huff and puff gas injection for a full field development was investigated. The operational pressure range, the injection schedule, and the injection rate were optimized to achieve a successful huff and puff pilot in this area to confirm the feasibility and maximize the knowledge.
A highly fractured and faulted reservoir in Mexico with an active aquifer was successfully characterized by NITEC’s in-house technology. Reservoir simulation resulted in the identification of highly productive zones which were confirmed by drilling.
Verification of the process was carried out for a thermal recovery process – insitu upgrading of hydrocarbons. Thermal simulation correctly correlated with laboratory results and a U.S. field evaluation considered Huff-n-Puff and continuous injection.
This light-oil field in Venezuela with a thin oil rim and overlying gas condensate zone was characterized and simulated. Understanding reservoir performance required identification and characterization of asphaltene deposition in the oil rim and detailed simulation of over 100 wells with multiple production strings. Simulation predictions provided new completion alternatives and workovers to improve future oil recovery.
An integrated reservoir study was carried out on a near depleted oil field in Wyoming discovered in 1916 with over 700 completions. The simulation model history match indicated substantial remaining oil in place. Extended black-oil simulation of CO2 WAG and continuous CO2 injection processes indicated significant tertiary oil recovery potential. Full-field development is in the planning stages.
Fracture characterization using seismic, wellbore and well performance data:
Limited performance and wellbore data in a recent oil discovery in India suggested the existence of a natural fracture system. Seismic, wellbore, and performance data, along with NITEC’s unified capillary pressure technology were used to confirm and describe the vertical and areal fracture distribution. Field development is being planned accordingly.
Secondary or tertiary recovery:
A prolific oil field in Wyoming with significant primary and secondary recovery was evaluated for bypassed secondary and tertiary oil potential. The natural fractures in the formation and the historical water injection resulted in little additional secondary oil recovery potential. Accordingly, the remaining oil in place was found to be insufficient to warrant an economically viable CO2 injection program. Other tertiary recovery processes are under consideration.
Storage expansion in faulted, fractured carbonate (OK, USA):
NITEC history matched a dual-porosity simulation model for this 40 BCF naturally fractured and faulted carbonate gas storage reservoir. The study required developing a new reservoir characterization for the nature fractures using NITEC fracture characterization technology. The model was used to evaluate the deliverability benefits from in-fill wells vs well workovers vs additional compression. (58 wells, 28.2 BCF working gas, 660 MMcf/d)
Improve deliverability with in-fill wells (TX, USA):
NITEC developed the reservoir characterization from old vintage well logs for this 65 well 75 BCF gas storage field which was input to the simulation model. The model was successfully history match and provided deliverability predictions for 15 in-fill wells increasing storage capacity to 96 BCF working gas with a peak rate of 1,230 MMCF/d
Vertical well replacement with horizontal wells (KY, USA):
NITEC completed a storage optimization study for a large storage field in Kentucky, initially with over 150 old vertical wells, 135 BCF Total gas and 730 MMcf/d peak deliverability. The history matched model was used to evaluate replacing old vertical wells with horizontal wells, surface gathering system improvements (12 branched/looped lines), and additional compression power. Currently, the field has 13 horizontal wells, increased deliverability to 1,030 MMcf/d, and improved working gas to total gas efficiency.
Gas Migration Control (Midwest USA):
NITEC developed a complex reservoir simulation involved two aquifer storage formations and an oil production – gas recovery formation above the main storage zone. This field was old with vintage well logs and data records. The objective for the study was to determine the volume of gas migration into the recovery formation over the past 50 years and provide operations strategy to minimize future gas migration.
Impact of 3rd party operations (KY, USA):
NITEC evaluated the impact of 3rd party E&P operations outside the storage boundary on this storage fields gas recovery-zone in the cap rock above the aquifer storage field. The storage and gas-recovery operations had been stable for many years until recent E&P activity in the surrounding areas was targeting the shale caprock. NITEC was able to confirm that the E & P activity was negatively impacting the storage operations and developed a counter-strategy to protect the stored gas in the recovery zone.
Increase working gas, control migration, in-fill wells (NE, USA):
NITEC conducted an integrated reservoir study in a complex fluvial sand gas storage field to provide operations strategies for controlling gas migration between the main storage structure and a small low productivity structure and improving deliverability and working gas capacity. The project resulted in 10 new wells which increased deliverability by 75 MMCF/d and increased working gas by 10 BCF and provided a strategy to eliminate the gas migration.
Buyer Due Diligence – Depleted oil converted to gas storage and oil production (TX, USA):
NITEC conducted a detailed evaluation of this complex gas storage field with oil production. The field was a faulted anticline resulting in partial compartmentalization impacting the communication from two portions of the gas bubble and the downslope oil leg. The valuation was dependent on confirming well productivity/deliverability rates and increased oil production with the storage expansion. NITEC was able to identify key areas of uncertainty regarding the production claims as well as regulatory issues that were used in the client’s valuation model.
Buyer Due Diligence – Depleted gas developed into gas storage (CO, USA):
NITEC represented the buyer in technical assessment meetings as part of our evaluation process. This field was comprised of two dome shape lobes connect through a syncline. The key issue for this field was to assess the connective between the two domes and additional base gas requirements as well as evaluate reservoir containment risks due to unmapped adjacent areas. NITEC provided the client with valuable insight in the stratigraphic complexities in this region.
Inventory Assessment Audit – 5 Fields (Midwest USA):
NITEC conducted an inventory verification/assessment audit for a client’s 5 gas storage fields which were a mixture of aquifer storage and depleted gas. The audit consisted of reviewing the client’s current inventory verification methodology and data and performing an independent evaluation of each storage field’s inventory behavior of the 6 year audit period.
Inventory Assessment/Verification Study– 8 Fields (Midwest USA):
Nitec performed a detailed inventory assessment study for this client’s eight (8) gas storage fields. The purpose of the study was to evaluate the impact on inventory and storage operations that may have occurred due to changes in the client’s methodology for tracking and accounting for lost and unaccounted for (LUF) gas. All eight fields were aquifer storage fields. NITEC evaluated each fields inventory with an aquifer material balance model and modified Pressure-Content (Hysteresis) methodology to determine the impact on the inventory, storage field deliverability and to make appropriate recommendations.
Old Carbonate Oil Field (SE USA):
NITEC conducted a detail field study to evaluate the gas storage potential of a deep depleted oil carbonate reservoir. The study included geology and petrophysics analyses to create a reservoir characterization model for a detailed reservoir simulation study. The simulation model history matched the original depletion period, matching oil, water and gas rates, and pressure observation data. Due to the depth and anticipated operating pressure for the storage operations, a compositional model was required to accurately predict the miscible interactions between the gas and remaining oil and the resulting oil production. The results were used to design the liquid handling requirements for the surface facility.
Old heavy oil field (Argentina):
NITEC performed a detail field study to determine the gas storage potential of a depleted oil fluvial sand reservoir. The study included geology and petrophysics analyses to create a reservoir characterization model for a detailed reservoir simulation study. The simulation model history matched the original depletion period, matching the oil and gas rates and pressure data. The optimal development required groups of 3 horizontal wells with gas injection used to sweep the remaining oil into the center production well, ultimately increasing the reservoir pore volume available for gas storage as well as recovering additional oil volume. The initial test development wells were drilled, proving the validity of the reservoir characterization, but economic conditions tabled the project.
Optimize Helium Recovery (TX, USA)
NITEC developed a complex reservoir simulation for the world’s only helium gas storage field. The storage operation is located in a natural fracture and faulted carbonate formation. NITEC performed an integrated reservoir characterization (stratigraphy, structure, petrophysics, and seismic) as well as using its fracture characterization technology to develop the dual-porosity 4 component composition simulation model. The model successfully history match 78 years of operations with over 3,500 pressure points and 7000 gas composition points. The model is still in use today for prediction the helium recovery as the storage field is being depleted and abandoned.