渤海垦利10-2区块录井综合解释评价方法研究

Research on comprehensive interpretation and evaluation method of mud logging in KL 10-2 block, Bohai Sea area

垦利10-2区块主要含油层系为新近系明化镇组及馆陶组,由于油藏埋深浅,成岩性差,钻井工艺的改变使得岩屑破碎严重,导致常规录井资料代表性变差,油气层准确识别难。为此通过红外光谱录井、地化录井、轻烃录井配套应用,从储层的含油气性、含水性等方面综合分析储层流体性质,弥补常规录井技术的不足,其中红外光谱录井侧重油气层的快速发现与识别,地化录井通过定量检测岩石含油气信息判识储层含油性,轻烃录井技术主要实现对储层含水性识别。基于对3项录井技术敏感参数的优选,建立了适用于渤海垦利10-2区块的解释图板,利用地化录井技术派生参数地化亮点值和红外光谱录井能量系数建立了含油性解释图板,利用轻烃录井技术派生参数戊烷异构化系数和C_(1)峰面积建立了含水性解释图板,同时归纳形成了该区块解释评价标准。该解释评价方法的综合应用在后期生产中取得了良好的效果,解释符合率由原来的77%提高到89%,提高了垦利10-2区块油气发现率和解释准确率。

The main oil-bearing formations in KL 10-2 block are Minghuazhen Formation and Guantao Formation of Neogene system. Due to oil reservoirs′shallow burial depth and poor diagenesis, the change of drilling technology makes the cuttings fragmented seriously, resulting in poor representativeness of conventional mud logging data and difficulty in accurate identification of hydrocarbon reservoirs. Therefore, through the assorted application of infrared spectrum logging, geochemical logging and light hydrocarbon logging, the reservoir fluid properties of the reservoirs are comprehensively analyzed from the aspects of oil-gas potential, aquosity and so on to make up for the shortage of conventional mud logging technologies. Among them, the infrared spectrum logging focuses on the rapid discovery and identification of hydrocarbon reservoirs, geochemical logging discriminates oil bearing property of reservoirs by quantitatively detecting the oil-gas bearing information of the rock, and light hydrocarbon logging technology mainly realizes the aquosity identification of reservoirs. Based on the optimization of the sensitive parameters of the three mud logging technologies, the interpretation charts suitable for KL 10-2 block in Bohai Sea area were established. One is an oil-bearing property interpretation chart between geochemical bright spot value derived from geochemical logging technology and energy coefficient of infrared spectrum logging, the other is aquosity interpretation chart for light hydrocarbon logging technology derived parameters of pentane isomerization coefficient and C_(1) peak area. At the same time, the interpretation and evaluation criteria of this block were summarized. The integrated application of the interpretation and evaluation methods has achieved good results in the later production, with the interpretation coincidence rate increasing from 77% to 89%, and improving the oil and gas discovery ratio and interpretation accuracy in KL 10-2 block.