摘要
香溪群四段是川中油气区主要产层之一,经几十年的勘探,探明了八角场整装气田。但随着川中矿区勘探工作的深入和经济建设对优质能源天然气需求量的增加,川中油气区香溪群四段已成为天然气勘探的重点层位。据川中油气田香溪群四段地层水实测样品数据所做的研究可以得到以下结论:①香溪群四段地层水水岩作用时间长、深循环、深度浓缩、正变质特征;②该段地层水中阴、阳离子含量差异大,钠、氯离子在水中占绝对优势,具有向组分端元集中的分异特点;③此地层水属油气伴生水;④常量、微量元素及特征系数因构造带不同,差异较大;⑤地层沉积水属混源水,既有陆相河湖淡水又有海相盐水;⑥地层水化学特征表明,香溪群四段具有天然气聚集成藏与保存所需的封闭、还原的水文地球化学环境;⑦各地层水化学指标都指明,受香溪群四段储层低孔、低渗透物性特征和古地理、古构造等的影响,川中地区香溪群四段形成了南(遂南、磨溪构造等)北(金华、八角场构造)各异的两个地层水水化学场,这预示着川中地区香溪群四段地层水动场也是南北相异的。香溪群四段水化学场和水动力场的相异表明川中地区的油气的运移和聚集成藏也是南北相异,自成体系的。
The fourth segment of Xiangxi group is one of key production formations in center oil-gas field of Sichuan basin.After several decades' exploration,the Bajiao gas field has been discovered.As the exploration going on and the need of nature gas being on the increase,the fourth segment of Xiangxi group becomes the key formation.Studies on the data of the formation-water experiments prove that: the formation-water of the fourth segment of Xiangxi group have been a long term water-rock interaction,deep-cycle,deep-concentration and positive-transformation course;the anion and cation concentrations the formation-water of the fourth segment of Xiangxi group vary largely and contents of the formationwater of the fourth segment of Xiangxi concentrate to two-end as Cl^-and Na^+ play an important role;the formation-water of the fourth segment of Xiangxi group belongs to oil-gas associated water;contents of normal element and microelement and characteristics coefficients vary largely by situation of structure;sedimentary water of the fourth formation of Xiangxi group was compounded by lake and marine water;the formation-water chemical characters dissertate that the fourth formation of Xiangxi group has the obturated,deoxidized geochemical surroundings that oil-gas accumulation needs,and its low-porosity,low-permeability and the difference source of water and gas bring the isolated formation-water field and different accumulation of gas and water by different situations.
出处
《物探化探计算技术》
CAS
CSCD
2006年第1期41-45,3-4,共5页
Computing Techniques For Geophysical and Geochemical Exploration
关键词
四川盆地
地层水
化学场
香溪群
油气
sichuan basin
formation-water
chemical field
xiangxi group
petroleum
