【摘要】 漏失压力是合理确定钻井液密度上限的重要依据之一。传统的漏失压力计算模型较为单一，难以全面准确地预测复杂地层的漏失压力。为此，提出了一种基于测井资料连续准确地计算井壁地层漏失压力的新方法，以满足新井钻井设计和施工的需要。针对钻井地质剖面中常见的孔隙性漏失、溶洞性漏失、裂缝性漏失和压裂性漏失这4种漏失类型，分析其漏失机理；参考传统的漏失压力计算模型，基于井壁岩石破裂准则，建立利用声波时差、体积密度和自然伽马等测井曲线计算井壁地层漏失压力的方法，包括裂缝性和压裂性地层漏失压力计算新模型。通过对关键井测井资料的岩石力学处理分析，准确得到了全井段地层漏失压力剖面，为研究区复杂地层的安全高效钻井提供了重要的防漏、堵漏决策依据。更多还原

【Abstract】 Leakage pressure is one of the important bases for reasonably determining the upper limit of drilling fluid density. The traditional calculation model of leakage pressure is relatively single, which is difficult to predict the leakage pressure of complex formation comprehensively and accurately. Therefore, a new method is proposed to continuously and accurately calculate the lost circulation pressure of wellbore formation based on logging data, so as to meet the drilling design and construction of new wells. Firstly, in view of the four common types of leakage in drilling geological profile, such as pore leakage, cave leakage, fracture leakage and fracturing leakage, this paper first analyzes the leakage mechanism. Secondly, referring to the existing calculation model of leakage pressure, based on the wellbore rock fracture criterion, establishes four methods of calculating the formation leakage pressure by using acoustic, density and gamma logging curves, including a new model for calculating leakage pressure in fractured and fractured formations. Based on the rock mechanics analysis of logging data of some key wells, the formation leakage pressure profile of the whole well section is accurately obtained, which provides an important basis for decision of leakage prevention and plugging for safe and efficient drilling in complex formations.更多还原