在油井开采早期进行地层流体取样 ,可以保证现有重要资料能及时输入油田设计决策中。特别是对于水下的井 ,保证流量事关重大 ,来自裸眼录井的地层流体样品对经营者优化上下游设施投资是有帮助的。原油因其含有大量而复杂的芳香族化合物而显示出不同颜色。由于合成的和油基的钻井泥浆含有简单脂肪族化合物 ,所以它们几乎不吸收波长较短色道的色彩。油基污染监视(OCM)技术就是应用光学法来监视取样过程中色彩的增强。该技术提供样品污染的实时分析 ,同时预测它达到可接受的轻度污染要花多长时间。当油层流体取代流送管中的滤液时 ,甲烷信号的光学密度 (OD)也与原油中的甲烷含量成正比增加。甲烷检测对凝析油以及颜色浅的原油是最基本的检测。对于这类流体 ,色彩增强是难以检测到的 ,然而 ,这些流体具有高含量甲烷气油比(GOR)。当这些借助甲烷的方法用于深色原油时 ,原油的色彩吸收延伸到近红外区 ,涵盖甲烷分子振动峰 ,造成甲烷的光学量级较高。如果对此未予校正 ,就会使借助甲烷的污染预测和GOR测量产生误差。本文介绍用甲烷信号的光学密度 ,在取样过程中 ,在井下测量GOR的方法。还描述从甲烷光道消除色彩效应的脱色算法。该算法是基于在近红外区色彩的吸收向长波长方向呈指数衰减。脱色后 ,甲烷道只含有 The sampling of formation fluid in the early stage of oil well extraction can ensure that the existing important data can be input into oilfield design decision in time. Especially for underwater wells, ensuring flow is of major importance. Formation fluid samples from open-hole logging wells are good for operators to optimize upstream and downstream facility investments. Crude oil shows a different color because of its large and complex aromatics. Because synthetic and oil-based drilling muds contain simple aliphatic compounds, they hardly absorb the color of the shorter wavelength channels. Oil-based pollution monitoring (OCM) technology is the use of optical methods to monitor the color enhancement during sampling. The technology provides real-time analysis of sample contamination and predicts how long it will take to achieve acceptable mild contamination. The optical density (OD) of the methane signal also increases in proportion to the methane content in the crude oil as the fluid in the reservoir displaces the filtrate in the feed pipe. Methane testing is the most basic test for condensate and light colored crude. For such fluids, color enhancement is difficult to detect, however, these fluids have a high content of methane gas oil (GOR). When these methane-based methods are applied to dark crude oils, the color absorption of the crude oil extends to the near infrared region and covers the vibrational peaks of methane molecules, resulting in higher optical magnitudes of methane. If left unadjusted, this could lead to errors in methane-based pollution predictions and GOR measurements. This article describes a method for measuring GOR downhole during sampling using the optical density of methane signals. A decoloration algorithm that eliminates color effects from methane tracks is also described. The algorithm is based on exponentially decaying the absorption of color in the near-infrared region towards longer wavelengths. After bleaching, the methane tract contains only