邻井LF-DAS光纤应变率信号响应正演模型

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中图分类号：TE934文献标识码：ADOI：10.12473/CPM.202404020

Abstract：Hydraulic fracturing is a key technology for eficient oil and gas development，and the monitoring of hydraulic fracture morphology is of great significance to the development ofoil and gas fields. Considering that the response modesofLF-DAS fiber strainrate signal arediverse and dificult to interpret，this paper extended the traditionalPKNmodel，andcombined thetheoryofsolidelasticdeformationtobuildaforwardmodeloffiberstrain rate signal based on semi-analytical - finite element method.Using this model，the fiber strain rate signal responses of horizontal and vertical adjacent wels in the process of single-cluster fracture propagation were simulated，indicating theresultsbasicallconsistentwiththeactualfiberdata.Then，the influences of monitoring distance and monitoring well deviation angleon fiber strain rate signal were identified.The analysis results show that as the deviationangle increases，the“blue-red-blue”strip in the strain rate waterfalldiagram tiltsand deforms.

The "blue-red-blue" strip has a significant application efect，and the strip width becomes wider with the increase of the monitoring distance.The monitoring distance has a great influence on the fiber strain rate signal strength which decreases with the monitoring distance in a power function.The research results provide atheoretical basis for using the LF-DAS fiber strain rate signal of adjacent wels to interpret the hydraulic fracture morphologyand guide the geometric arrangement of monitoring wells.

Keywords： hydraulic fracturing；fracture monitoring;LF-DAS；optical fiber interpretation；monitoring distance；strain rate；forward model

0 引言

随着油气勘探开发从常规油气转向非常规油气，储层物性逐渐劣化，通常具有低孔、低渗的特征[1，为了实现商业化开采，必须通过储层改造手段来达到经济开采的目的。（剩余12465字）