川东北区农业产业化经营策略初探

农业在川东北区域经济发展中具有举足轻重的地位,加快该区域的农业产业化经营对于促进农业进步,增加农民收入,推进新农村建设,具有极其重要的意义。分析了川东北区农业产业化经营存在的主要问题,提出了相应的策略与经营模式。

川东北及川东区天然气成因类型探讨

通过对川东北、川东区11口钻井天然气组分及其烷烃碳同位素的研究表明,两区天然气成因类型明显有别,川东北天然气为过成熟裂解混源气,其中,Ⅱ—Ⅲ1类型母质烃源岩的贡献可能大于Ⅰ1—Ⅰ2类型母质烃源岩的贡献;川东区建南气田长兴、飞三、嘉一产层天然气多属Ⅰ1—Ⅰ2类型母质烃源岩过成熟裂解混源气;个别天然气表现为煤型气与油型气的混源气,腐泥型有机质的贡献可能大于腐殖型有机质的贡献;石炭系产层天然气可能为志留系所生原油的二次裂解气。

峨眉地裂运动观对川东北大气区发现的指引作用

目前川东北已成为上万亿立方米储量的礁滩相大气区,它是如何获得的?其原因很多,其中,在这一大气区的发现过程中,由笔者30多年前创建的"峨眉地裂运动观"起到了一定的指引作用。依据公开发表的历史文献,分阶段论述了大气区研究过程和勘探成果,并探讨了峨眉地裂运动作为川东北礁滩相沉积的大地构造背景和对大气区成藏条件的控制作用。最后,从认识论的角度总结出科研工作的几点经验。建议重视以地裂运动观研究四川和塔里木二个克拉通盆地有沉积岩和火山岩兼备的复合地层,预期今后还会发现更多有机或无机的天然气资源。

川东北地区深井固井技术综述

深井、超深井固井,尤其是气井,难度非常大,有的问题可以说是世界级的难题。川东北是我国陆上油气田开发最复杂的地区之一,不仅井深,而且井下高温、高压、高含硫化氢气体,在同一裸眼井段往往有不同的压力系统,井漏、井涌现象严重,钻井难度大,固井难度更大。中原油田固井工程技术人员通过科技攻关,优选了固井工艺技术,开发了特种水泥浆体系,成功地解决了这一复杂地区的固井技术难题,使固井质量得到了保证。

收入不确定性、风险应对机制与农户生产经营决策——川东北传统粮区的实证

本文采用logistic回归方法,对川东北传统粮区878户农户的问卷调查数据进行了计量分析,检验了在收入风险冲击下,农户可选的风险应对机制及这种机制对农户生产经营的影响。结果表明:在正规收入风险机制缺失的背景下,农户会选择一些非正规的机制应对风险。由于事后的风险处理机制受到限制,农户不得不在很大程度上依靠事前机制来规避收入风险。目前,生产经营中的保守行为是农民规避风险的主要方式,但这种事前机制将同时在效率和公平方面带来负面影响。

川东北丘区农业产业化现状及发展建议

川东北丘区农业产业化建设已有良好开端,但也面临着一些问题和制约因素。建议在改造传统农业、发展现代农业新的进程中,通过夯实基础、创新机制、科学规划、优化布局、提升品牌,丘区农业产业化建设大有可为。

川东北高含硫气井完井修井工艺技术探讨

就川东北地区高合硫气井完井修井的现状、基本思路及完井方法,完井修井工艺管柱、套管、油管、井下工具、采气井口装置、完井液、射孔、地面测试流程、酸液与产层的配伍性、酸化增产措施适应性、试修设计等工艺技术的现状和存在的问题进行分析,并提出具体建议。

钻井液密度窗口随钻预测理论及其工程应用

将岩石力学方法与地震勘探理论相结合,通过考察地震记录、岩石物理参数与孔隙压力之间的定量关系,建立了利用地震数据直接反演孔隙压力的模型。根据岩石力学参数地质统计特性,实钻过程中充分利用录井、钻井等实时信息,通过随机反演方法随钻预测钻头前方待钻地层的孔隙压力。依据孔隙压力反演结果进一步求取地应力、岩石强度、坍塌压力与破裂压力,通过对预测参数的综合分析,最终实现对待钻井段的安全钻井液密度窗口进行随钻预测。该方法在川东北HB探区的2口深探井进行了工程应用,现场应用情况表明该方法预测精度较高、实时操作简捷、计算过程稳定,具备良好的随钻适用性。

Formation mechanism of reservoir oolitic dolomite in Lower Triassic Feixianguan formation, northeastern Sichuan Basin, southwest China

A series of marine natural gas fields were recently discovered in oolitic dolomites of the Lower Triassic Feixianguan formation, northeastern Sichuan Basin, southwest China. The mechanism forming these reservoir dolomites is debatable, limiting the ability to characterize these reservoir successfully. Based on the investigation of the representative Dukouhe, Luojiazhai, and Puguang areas, this issue was addressed by examining the distribution, petrology, and geochemistry of the dolomites, the most comprehensive study to date was provided. Dolomitization occurred at a very early stage of diagenesis, as shown by the petrological features of the rock fabric. Vadose silt, which is composed primarily of dolomitic clasts, is found in the primary and secondary pores of the oolitic dolomite. This indicates that the overlying strata were subjected to dolomitization when the Feixianguan formation was located in the vadose zone. Therefore, it may be inferred that the dolomitization which occurred before the formation was exposed to meteoric conditions. The spatial distribution and geochemical characteristics of the dolomite indicate that dolomitization occurred as a result of seepage reflux. The degree of dolomitization decreases with increasing distance from the evaporative lagoon. Furthermore, the type and porosity of the dolomite vary in different zones of the upward-shoaling sequence, with the porosity gradually decreasing from the highest layer to the lowest layer. This reflects a close relationship between dolomitization and seawater evaporation during the formation of the dolomite. Geochemical analysis provided further evidence for the relationship between the dolomitization fluid and the coeval seawater. The 87Sr/86Sr and 813C isotopes, as well as the abundances of trace elements, Fe and Mn, indicate that seawater concentrated by evaporation acted as the dolomitization fluid. These results also show that dolomitization most likely occurred in a semi-closed diagenetic environment. Therefore, the main mechanism of oolitic dolomite formation is seepage reflux, which occurred at an early stage of diagenesis.

The construction of technical standard system for ultra deep and high sour gas fields in Northeast Sichuan

To deal with the exploitation difficulties of gas fields in Northeast Sichuan with deep marine strata, after researching the relative standards domestic and abroad extensively, summarizing and promoting the successful experiences and failure lessons of project construction technology application scientifically, Sinopec has established an integrated technical standard system for the exploration and development of ultra deep and high sour gas fields. The system consists of 51 enterprise standards and covers 7 professions including geophysical prospecting, drilling, drilling log, well logging, gas formation test and production, sour gas gathering and transferring system, and HSE (health,safety,environment). It guides and guarantees the safe, high-quality and high-efficiency project construction effectively by means of enhancing the engineering design criterion, recommending the data processing and interpretation methods, identifying the requirements of operation and field inspection and standardizing the application of technical equipments.

Temperatures of dolomitizing fluids in the Feixianguan Formation from the Northeastern Sichuan Basin

The discovery of natural gas reservoirs from the Triassic Feixianguan Formation in the Northeastern Sichuan Basin is an important breakthrough in the field of marine carbonate rocks for Chinese oil and gas exploration in recent years.Because of the dolomite-hosted reservoirs in the Feixianguan Formation,these dolomites and their formation mechanisms have been a research focus for sedimentary geologists and petroleum geologists.Based on the homogenization temperatures of fluid inclusions,oxygen isotopic composition and their calculated temperatures,and the burial and thermal history of the typical well,it is considered that the majority of dolomites are formed by low-temperature dolomitizing fluids in the Triassic Feixianguan Formation,Northeastern Sichuan Basin.Only a minority of dolomites are formed by high-temperature dolomitizing fluids.The ending depth interval of low-temperature dolomitizing fluids was about 1000-2500 m,of which the correspondingly ending timing interval was approximately from early-middle Middle Triassic to early-middle Late Triassic.The main depth interval of high-temperature dolomitizing fluids was about 3200-4500 m,of which the correspondingly main timing interval was approximately early-middle Middle Jurassic.The low-temperature and high-temperature dolomitizing fluids have different meanings to the formation and evolution of the pore volumes of dolomite reservoirs in the Feixianguan Formation,Northeastern Sichuan Basin.

Community replacement sequences and paleoenvironmental changes in reef areas of South China from Late Permian to Early Triassic exemplified by Panlongdong section in northeastern Sichuan Basin

The well-known Permian Changhsingian calcisponge reef located at Panlongdong section,Xuanhan county,northeastern Sichuan Basin has attracted wide attention.Due to severe dolomitization and poor quality of the fossils,the P-T boundary in this section is difficult to determine.This study,for the first time,recognized six communities in the Upper Permian Changhsingian Changxing Formation through the Lower Triassic Induan Feixianguan Formation of the Panlongdong section.They are Bryozoan-Archaeolithoporella-calcisponge Community,Calcareous green algae-foraminifer-crinoid Community,Microgastropod-foraminifer Community,Ostracod-microgastropod-cystic microbe Community,Ostracod-small brachiopod Community,and Non-calcified cyanobacteria Community.By using community replacement and palaeoenvironmental analysis,for the first time,we set the P-T boundary of the Panlongdong section at the middle of the calcimicrobialite containing cystic microbes.The community replacement sequence in the Panlongdong section is similar to that in other contemporaneous sections in reef areas of South China,indicating universal palaeoenvironmental changes during the Permian-Triassic transition.The results show that:(1)Changhsingian calcisponge reefs in South China generally vanished before the mass extinction and may be related to the large regression in the Late Permian.(2)The Calcareous green algae-foraminifer-crinoid Community replaced reef community and continued till the mass extinction.The mass extinction was probably related to the global sea-level drop.(3)The first aftermath community was dominated by specialized microgastropods,followed by the microbes,and then by the specialized microgastropods and small brachiopods.The succession of the three communities reflected the change in environmental conditions from dysoxic to anoxic and again to dysoxic.(4)In the Early Triassic,the relict community in shallow sea had very low diversity and low abundance,and was dominated by crinoids,gastropods,and bivalves.