In the last decade, improvements within the oil and gas production industry have been achieved using horizontal drilling and multi-stage fracturing.
With an increase in the volume of horizontal wells drilling, the length of horizontal wells, and the number of MFrac stages, an increase in oil production does not often achieve the forecasted levels. One of the most important tasks of field development is to obtain complete information on the productive intervals of well inflows.
Conducting geophysical studies and interpreting results that have proven themselves in vertical wells compared to horizontal wells. Horizontal wells are complicated by the flow multiphase character, changes in the well fluid velocity, and the presence of ascending and descending sections in the horizontal well trajectory.
Direct transfer of research technology and interpretation algorithms from vertical to horizontal wells leads to inaccurate, unreliable conclusions.
Production logging with markers detects highly productive intervals and characterizes the formation fluid.
The inflow profiles determination in production wells is the basis for the adoption of technical decisions on the development of the most efficient oil and gas fields and optimization of solutions for well pumping or performance of general repairing works.
Until recently, there has been no viable alternative to down-hole logging operations in the industry to determine the locations of water inflow into the well, OWC position and control of its movement, allocation of watered reservoirs, and evaluation of activities that improve oil recovery such as hydrochloric acid treatment or multi-stage hydraulic fracturing.
However, horizontal well production logging is an expensive procedure that requires the use of coiled tubing (CT) service or tractors. The feasibility and success of the operations depend on the seasonal availability of the well itself, the shape complexity, curvature intensity, and the locations of the changes in the internal diameter of the casing string.
This solution overcomes several technical constraints, such as well intervention, studies conducted in artificial mode, and the restrictions on production logging for a range of MFrac completions. Cassettes that are lowered into the well allow users to obtain detailed information on the well inflows.
Existing solutions do not allow users to conduct long-time monitoring or obtain a dynamic picture of production per interval. Moreover, well intervention could lead to lost equipment and costly recovery operations.
One of the alternative methods to well inflow profiles monitoring is the GEOSPLIT® technology, based on the use of marker-reporters® created from quantum dots.
Studies of the wells using marked proppant show the process is not limited by the restrictions mentioned above and increases the efficiency of well inflow diagnostics after MFrac in the oil and gas fields development.
The placement of marker-reporters® in the oil reservoir for long-term periods and their subsequent analysis gives users an unprecedented level of well management capabilities.
The fundamental difference between this technology and conventional production logging is the ability to monitor production per interval for long periods. This new approach results in a drastic reduction in required resources and improves safety.