Overcoming Production Logging Challenges in Evaluating Extended Reach Horizontal Wells with Advanced Completions

Objective/ Scope Production logging analysis is essential to understand and evaluate reservoir performance throughout the lifetime of an oil well. Data acquisition and analysis is known to be challenging in modern extended reach horizontal wells due to multiple factors such as conveyance difficulties, fluid segregation, debris, or open hole washouts. Advanced compact multiple array production logging tool (APLT) is proposed to minimize the uncertainties related to these challenges. Method, Procedure, and Process The proposed sensor deployment method provides a comprehensive borehole coverage, thus maximizing the amount of subsurface information collected to evaluate the production performance of a horizontal well. Essential measurements are combined on six individual arms. Each arm is independently deployed which guarantees the best borehole coverage in a variety of borehole condition. Robust mechanical arm design minimizes damage, allows tolerance to decentralization, and provides greater confidence in determining the sensor locations. Each arm utilizes two fluid holdup sensors (Resistance, Optical) and one velocity sensor (Micro-Spinner). Co-location of the sensors minimizes the uncertainty related to sensor spacing when compared with previous generation of APLT. Results, Observations, Conclusions The new sensor deployment method and analysis results are discussed showing the added value in barefoot completion as well as advanced ICD completion. The holdup sensors response from previous generation APLT is compared to the advanced tool and how it relates to better borehole coverage. The results also illustrate use of high frequency optical probes for phase holdup determination. In addition, the optical probes are used to confirm bubble point pressure at in situ conditions by confidently detecting the first gas indication in the tubular. The results clearly show how a compact APLT maximizes the borehole coverage in highly deviated and horizontal wells. This is critical in collecting representative data of all segregated fluids which enables more accurate interpretation of the flow profile in the well and better understanding of reservoir performance. Novel / Additive Information The novelty of the new instrument is the ability to maximize the amount of subsurface production logging information collected with low uncertainty and minimum operational risk.

Quantification of Fluid Production Distribution in Deviated Wells with High Gas-Liquid Ratio Using a Flow Array Sensing Tool

The objective of this paper is to depict the quantification of the production rates of the different phases in deviated wells with high gas-liquid relation using the Flow Array Sensing Tool (FAST). The readings of standard Production Logging Tools (fullbore flowmeter, density, and capacitance) are centralized, therefore they are affected if there is re-circulation of the heavy phase (liquid). The phase segregation and possible apparent down flow of the heavy phase makes it very difficult to determine the distribution of the produced fluids, and in some cases the spinner flowmeter tends to stop or gives inaccurate readings. The cause of these inaccurate readings is that the centralized spinner is affected by positive flow in the high side and negative flow in the low side of the wellbore, and the spinner shows no flow or even apparent downhole flow, when there is a real positive flow. The FAST tool used during the acquisition of the production logs is an ultracompact production logging tool (3 ft long) that is capable to measure multiphase flows with an array of 8 sensors, two in each arm and located 90° apart. These sensors are based on MEMS (Microelectromechanichal Systems), and among the interchangeable sensors we have optical probes that takes ultra-rapid measurements of the refractive index and can determine hold-up of water, oil and gas; the electrical probes that measures conductivity to differentiate hydrocarbons from water, and magnetic probes with micro-spinners to determine the flow rate. Both the three phase optical probes and the electrical probes have excellent response including water hold-ups over 90% that cannot be measured with a standard capacitance tool. The data logged with FAST in deviated wells was processed and interpreted to obtain the apparent flow velocity profiles of each of the 4 micro-spinners and with the three phase optical probes, and the relative bearing curves the velocity maps, and hold-up maps where obtained. The velocity map showed that there was negative flow in the low side of the well and positive flow in the high side while the hold-up map showed the light phase (gas) in the high side of the well. Both maps showed clearly the flow pattern and were used to quantify the production of each perforation and the total rate matched closely the surface rate (within 2% deviation). With the hold-up and velocity maps, the real flow rates were obtained with high confidence, and the flow pattern were shown clearly in deviated wells. The three phase optical probes, and electrical probes are excellent indicators of water and hydrocarbons inflow in a wide range of hold-ups.

Iron oxide nanoparticles conjugated with organic optical probes for in vivo diagnostic and therapeutic applications

The role and scope of functional inorganic nanoparticles in biomedical research is well established. Among these, iron oxide nanoparticles (IONPs) have gained maximum attention as they can provide targeting, imaging and therapeutic capabilities. Furthermore, incorporation of organic optical probes with IONPs can significantly enhance the scope and viability of their biomedical applications. Combination of two or more such applications renders multimodality in nanoparticles, which can be exploited to obtain synergistic benefits in disease detection and therapy viz theranostics, which is a key trait of nanoparticles for advanced biomedical applications. This review focuses on the use of IONPs conjugated with organic optical probe/s for multimodal diagnostic and therapeutic applications in vivo.