Based on the lithologies, sedimentary structures, graptolite zones, inorganic geochemical characteristics, electrical data of 110 shale gas wells in southern Sichuan Basin and the mineral quantitative analysis technology of scanning electron microscope, the stratigraphic sequences of the Upper Ordovician Katian Stage–Himantian Stage–Silurian Rhuddanian Stage–Aeronian Stage are divided, the sedimentary characteristics and fourth-order sequence evolution are analyzed. The target layer can be divided into two sequences, namely SQ1 and SQ2. According to Ordovician–Silurian sedimentary background, the gamma value of the target layer and U/Th, 5 maximum flooding surfaces and 12 system tracts are identified. According to system tracts and their combinations, eight fourth-order sequences are identified, namely, Pss1–Pss8 from old to new. The development period and scale of dominant shale facies from Katian stage to Aeronian stage in southern Sichuan are restored. The best-quality dolomite/calcite-bearing siliceous shale facies, siliceous shale facies, clay-bearing siliceous shale facies and feldspar-bearing siliceous shale facies mainly occur in Pss3–Pss5 of Weiyuan, Western Chongqing and Luzhou, Pss6 of Western Changning– Northern Luzhou–Central Western Chongqing and Pss3–Pss4 of Changning. The siliceous clay shale facies second in quality mainly occurs in Pss6 of Southern Luzhou–Changning area (excluding Western Changning area), Pss7 of Eastern Weiyuan– Northern Western Chongqing–Southern Luzhou and Pss8 of Northern Luzhou–Weiyuan–Western Chongqing. The fourth-order sequence evolution model of Katian stage–Aeronian stage in southern Sichuan is established. During the depositional period of Pss1–Pss8, the sea level had six regressions and five transgressions, and the first transgression SQ2-MFS1 after glaciation was the largest flooding surface.

吸附气是页岩气的重要赋存形式和组成部分.为了明确四川盆地长宁地区五峰组—龙马溪组一段页岩在埋藏过程中吸附气含量的演化规律,利用页岩等温吸附实验、钻井现场解吸和测井综合解释资料,建立了页岩吸附气含量与地层温度、地层压力、页岩TOC等主要影响参数的多元回归数学公式,结合典型评价井(N201井)的埋藏史、热史,对不同地质时期页岩吸附气含量进行定量计算.计算结果表明:自侏罗纪有机质开始大量生气以来,页岩吸附气含量随着埋藏深度的增加逐渐升高,到白垩纪末期吸附气含量达到4.42 m3/t;古近纪以来,随着上覆地层被大幅度剥蚀,页岩吸附气含量逐渐降低至现今的1.67 m3/t.

针对传统的翁氏和Weibull产量预测模型受指数预测误差的影响而易出现指数倍级别的偏差,不能有效拟合四川盆地油气产量发展趋势的问题.提出了一种基于倍数和指数修正系数的模型修正方法——基于原始数据和一次计算结果计算指数与倍数修正系数,指数修正系数通过调整对模型影响较大的e指数消除数量级上的计算误差,倍数修正系数修正整体计算误差,再利用原产量函数中的t子函数指数多值求解,选取最优解减少预测曲线与原始数据变化规律的差异性,构建符合四川盆地产量发展特点的峰值预测模型.研究结果表明:①基于上述方法改进的翁氏模型和Weibull模型能够有效模拟四川盆地油气产量变化趋势并预测其全生命周期的产量变化趋势;②该盆地天然气产量峰值时间将出现在2050年左右,峰值产量为1453.28×108～1750.38×108 m3;③改进模型具有较高的预测精准度,在油气发展预测工作中具有一定的决策参考价值.

井壁稳定是当前水基钻井液钻深层页岩气的技术难点.以二乙烯三胺和N,N-亚甲基双丙烯酰胺为原料,通过迈克尔加成反应合成了超支化聚合物HP-NH2.采用红外光谱法、液相色谱-质谱联用法、凝胶色谱法、粒度分析法和热失重分析法表征了HP-NH2的结构和特征.研究发现,HP-NH2的数均分子量为3371 g/mol,多分散指数为2.7,分子量分布较宽,粒径280～1900 nm,抗温能力达到280℃.通过线性膨胀实验、回收率实验、泥饼分散实验和"人造泥饼"法分析了HP-NH2作为防塌剂的防塌性能.研究表明,随着HP-NH2浓度的增加,膨润土的线性膨胀率逐渐降低(最低为19.11％),岩屑的滚动回收率逐渐升高(最高为75.18％),人造泥饼的渗透率逐渐下降.小分子HP-NH2能够插入蒙脱石的晶层间,交换出层间易水化的阳离子,拉紧基底间距,抑制蒙脱石的水化分散;大分子HP-NH2能有效封堵泥饼的微纳米孔缝,起到一剂多用的功效.因此,HP-NH2可作为一种潜在的一剂多用防塌剂应用于水基钻井液体系.

文章通过对川东石炭系气藏开采过程中产出地层水特征、机理分析,将出水气井归纳为沿高渗裂缝水窜、沿网状缝局部水侵和均匀水侵三种类型.三种水侵类型在地层中的水侵速度,以及对气藏开采的影响和危害各不相同,从而不同程度影响气藏和气井的开发效益.文中提出了预测和治理石炭系气藏地层水水侵和产水的主要措施.

在四川盆地目前已投入开发的飞仙关气藏中,铁山气田飞仙关气藏是储渗条件最好、储量和产能规模最大、稳产能力最强、开发效益最好的气藏.该气藏已稳产6年,产量、压力稳定,开发效果好,且气藏具有较大的开发生产潜力.从目前东输项目地面建设工程进度的实际出发,为确保东输初期对气量的需求.本次研究通过对川东气区重点气田的分析认为:铁山等气田具有开发生产潜力,可以适当提高气藏采气速度,扩大生产规模,以此作为一项确保实现东输初期产量目标的保障措施.

渡口河气田飞仙关组鲕滩储层发育,储渗性能良好,储量规模大,气井产能高,是川渝天然气东输工程的主供气田之一.东输项目根据渡口河气田飞仙关气藏开发评价方案的气藏工程和地面建设工程推荐方案,确定采取就地脱硫的方式.在气田附近新建天然气净化厂,新建净化气外输管线,净化气外输两湖地区.目前,各项地面建设工程项目正按方案进行.