基于电磁支撑剂的水力压裂裂缝监测理论与方法

Hydraulic fracturing is the pivotal technology of tight unconventional oil and gas reservoir, and accurate monitoring of fracture morphology is related to fracturing effect evaluation,well productivity prediction, the follow-up measures which is the key to success of failure. How to get the exact monitoring information is the core of the fracture description.Compared to traditional methods, such as microseismic, near wellbore monitoring,electromagnetic monitoring can obtain the Effective Propped Volume that actually reflects the oil well productivity, solve the abuse such as low fracture identification accuracy, monitoring by the specific time limit.The electromagnetic monitoring theory and method is not perfect.The main contents are as follows：1) select the magnetic proppant applicable to fracture monitoring,2)research and develop the electromagnetic signal monitoring device based on magnetic proppant,3)analysis the filling manner and distribution mechanism which influences the magnetic signal strength,4)propose the inversion theory of hydraulic fracture morphology based on electromagnetic theory.This project will form a complete set of theory and method of hydraulic fracture monitoring based on electromagnetic,exactly obtain the Effective Propped Volume, accurately predict oil well productivity, provides theoretical support for the development of new hydraulic fracture monitoring technology, in order to achieve the optimal effect of well stimulation.

水力压裂是致密非常规油气开采的关键技术。裂缝形态的准确监测是决定压裂效果评价、油井产能预测、后续压裂措施成败的关键，如何得到准确的监测信息是裂缝描述的核心问题。与微地震、近井筒监测等传统方法相比，电磁监测能够得到真实反映油井产能的有效支撑体积，解决压裂裂缝识别精度不高、监测受特定时段限制等难题。目前，电磁监测相关理论和方法还不完善，拟开展主要内容如下：1）优选适用于压裂裂缝监测的磁性支撑剂，2）研发磁性支撑剂电磁信号监测装置，3）研究影响磁性支撑剂电磁信号强弱的填充方式与分布机理，4）提出基于电磁理论的水力压裂裂缝形态反演理论。本项目将形成一套完整的基于电磁支撑剂的水力压裂裂缝监测理论与方法，精确获得有效支撑体积，准确预测油井产能，为水力压裂裂缝监测新技术的开拓提供理论支持，以达到最佳压裂增产效果。

The stimulated reservoir volume（SRV）technology extends conventional fracturing technology. How to effectively and accurately determine modified fracture shape and volume is the key point to evaluating the stimulation effect. Using electromagnetic detection technology can provide a new option for measuring these parameters. By this method, we run the forward simulations based on infinite method, and electromagnetic signals of electrically conductive proppant which is pumped into fracture can be collected by different electromagnetic logging tools. .By comparing the different collected signals, we find that the obtained signals have a specific correspondence with fracture geometric parameters. According to the electromagnetic signal curve of the forward model, the description of propped fractures including positions and sizes can be realized, which verifies the feasibility and effectiveness of using this electromagnetic detection method to realize the electromagnetic monitoring of propp