川东北地区天然气化探方法试验研究

RESEARCH ON GEOCHEMICAL EXPLORATION TECHNIQUE FOR NATURAL GAS IN THE NORTHEASTERN SICHUAN AREA

孙长青 陈银节 荣发准 任春

Sun Changqing Chen Yinjie Rong Fazhun Ren Chun

中国地质大学, 武汉, 430074 2. 中国石油化工股份有限公司, 石油勘探开发研究院, 无锡石油地质研究所, 江苏, 无锡, 214151

China University of Geosciences, Wuhan, Hubei 430074, China 2. Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214151, China

油气化探以检测烃类气体为主的方法具有快速、有效和低成本的优势,在天然气勘探中能发挥积极作用。为了筛选适合川东北地区地表及地质条件的有效天然气化探方法,以川东北普光气田和元坝区块为试验区,通过样品采集方法试验、化探指标有效性和异常重现性研究,认为采集地表较常见的由侏罗系红色泥岩风化形成的残积物,进行顶空气、酸解烃、热释烃等烃类测试,采用烃类浓度高值及烃类累乘确定异常边界、烃类干度(C1/C2+)确定异常主体,能快速识别天然气有利区,并在元坝地区取得较好预测效果。

The hydrocarbon gases-oriented geochemical exploration technique has the advantage of quickness,effectiveness and low cost,and may play active roles in natural gas exploration.Some experiments and researches,including experiments for sample-collecting methods,researches on the effectiveness and the repeatability of the geochemical indicators,have been made in the Puguang Gasfield and Yuanba Block in the Northeastern Sichuan Experimental Area in order to select the effective geochemical indicators suitable for the surface and geological conditions of the study area.As the result,the geochemical indicators of headspace hydrocarbon,acid-extraction hydrocarbon and heat-released hydrocarbon of the common surface residual soils caused by the weathering of the red Jurassic mudstones have been selected.The results show that when the high concentration values,the accumulation factor,and the dryness degree(C1/C2+) of these hydrocarbons are used to determine the main anomaly,they can quickly identify the favorable accumulation area for natural gases,and have already achieved good prediction effects in Yuanba Block.

国家科技重大专项课题“大型油气田勘探开发遥感与化探配套技术”(2008ZX05020-006)资助

https://doi.org/10.11781/sysydz201002186