New Method Diagnoses Fracturing Interference in Horizontal Well Groups

Engineers have developed a new method for diagnosing and evaluating fracturing interference between horizontal wells in unconventional reservoirs, addressing a long-standing gap in how operators understand when hydraulic fractures from one well affect neighboring wells.

These interactions, known as fracturing interference, can either help or hinder the stimulation of the well group, and until now there has been no systematic evaluation system for their effectiveness.

The research team built a fracture propagation model based on the principles of unconventional complex fracture modeling. Using this model, they forward-simulated the spatial distribution of inter-well fractures under four typical interference patterns: a non-propagating fracture pattern, a main fracture propagation pattern, a branch fracture propagation pattern, and a natural fracture connectivity pattern. From these simulations, they developed diagnostic criteria for identifying each interference type in horizontal well groups.

The diagnosis relies on information that operators already collect during treatment. According to the study, the criteria draw on fracturing treatment curves, pump-stopping pressure drop curves, and pressure responses observed in neighboring wells.

To go beyond diagnosis and quantify the consequences of interference, the team constructed an interference well-test evaluation model based on pressure falloff well-test interpretation, adapted to the characteristics of inter-well fracturing interference. This inverse calculation recovers fracture parameters from pressure behavior, allowing the researchers to analyze how well fractures remain propped under different interference patterns.

The combined approach forms a coupled forward-inverse framework: the fracture propagation simulation predicts what fracture geometries should look like, while the pressure drop inversion works backward from field measurements to estimate actual fracture parameters. Comparing the two reveals how much propped fracture volume is gained or lost when interference occurs.

Applying the method to a typical fracturing interference horizontal well group in the Daniudi Gas Field in the Ordos Basin of China, the researchers found that the impact of interference on stimulation effectiveness follows a clear order: the main fracture propagation pattern has the largest effect, followed by the branch fracture propagation pattern, with the natural fracture connectivity pattern having the smallest effect.

The direction of that effect differs sharply between patterns. The main and branch fracture propagation patterns are harmful, reducing propped fracture volume by 7.2 percent and 4.6 percent respectively. In contrast, the natural fracture connectivity pattern is beneficial, increasing propped fracture volume by 3.5 percent. These figures come from the model-based evaluation of the studied well group.

The field application demonstrated that the method can effectively diagnose interference types and quantify their effects, and the results were validated by comparison with microseismic monitoring data. This agreement between the pressure-based inversion and independent microseismic observations supports the reliability of the workflow in a real field setting.

The authors suggest the workflow provides a practical tool for optimizing fracturing design in unconventional reservoir development, helping operators distinguish harmful interference that erodes stimulation effectiveness from beneficial fracture connectivity that enhances it. The published version is an open-access article shared early as accepted peer-reviewed research, subject to final editorial edits.

Subject of Research: Diagnosis and evaluation of hydraulic fracturing interference in horizontal well groups

Article Title: Diagnosis of fracturing interference and effect evaluation in horizontal well groups

Article References: Yuan, B., Zhang, S., Wang, F., Wang, X., Gao, K., Yu, C., & He, J. (2026). Diagnosis of fracturing interference and effect evaluation in horizontal well groups. Geomechanics and Geophysics for Geo-Energy and Geo-Resources. https://doi.org/10.1007/s40948-026-01202-x

Image Credits: AI Generated

DOI: 10.1007/s40948-026-01202-x

Keywords: hydraulic fracturing, horizontal wells, fracturing interference, unconventional reservoirs, propped fracture volume, well-test interpretation, pressure falloff, fracture propagation modeling, Daniudi Gas Field, Ordos Basin, microseismic monitoring, stimulation effectiveness