鄂尔多斯盆地陇东地区长7段致密砂岩微孔隙特征

致密油是当今非常规油气领域的研究热点。鄂尔多斯盆地长7段已发现致密油储量丰富,是中国最主要的致密油区之一。前人研究表明,纳米级孔喉对于非常规油气储层具有重要意义。采用氮气吸附、镜下观察、孔渗分析、X-射线衍射分析及粒度分析等实验手段研究长7段致密砂岩微孔隙特征,计算微孔分布、孔隙结构参数、微孔在总孔隙中的比例,并讨论了微孔隙类型以及矿物成分、粒度、分选对微孔发育的影响。研究表明,长7致密砂岩微孔隙结构复杂,微孔主要由 “墨水瓶”型孔和平行壁狭缝型毛细孔组成,主要以黏土晶间孔及层间缝、云母层间片状孔、溶蚀微孔及杂基粒间微孔的形式存在。微孔体积分布在(2.40～13.04)×10^-3cm³/g之间,约占总孔隙体积的1/4左右,微孔分布可分为2类：双峰型和单峰型。此外,对微孔体积与矿物成分、粒度及分选进行相关性分析,发现微孔体积与黏土矿物含量呈正相关关系,与碳酸盐矿物含量呈负相关关系;而微孔体积与石英+长石含量、中值粒径、标准偏差没有明显的相关性。因此,可认为长7段致密砂岩的黏土和碳酸盐矿物对其微孔的发育有一定的影响。     

碱性环境成岩作用及其对储集层质量的影响——以准噶尔盆地西北缘中—下二叠统碎屑岩储集层为例

根据铸体薄片、扫描电镜、电子探针、X射线衍射、岩石物性等资料,详细研究了准噶尔盆地西北缘中—下二叠统碎屑岩岩石学特征、成岩作用,在此基础上探讨碱性环境成岩作用对储集层储集性能的影响。结果表明：中—下二叠统广泛发育碱性环境成岩作用,包括火山碎屑水解、火山碎屑钠长石化、沸石类矿物形成、绿泥石形成等。碱性环境下发育多种伴生孔隙：火山碎屑碱性溶孔、钠长石化伴生孔、黏土矿物晶间微孔。碱性环境成岩作用对中—下二叠统碎屑岩储集层影响主要有：碱性流体造成储集层流体压实效应强,即碱性流体下储集层压实率高,对原生孔隙保存不利;碱性环境成岩作用下储集层自生矿物含量高,局部胶结减孔量大;碱性流体溶蚀增孔效率高,火山岩屑的碱性溶蚀孔隙可以成为重要的储集空间。     

致密砂岩储层石英溶蚀成因及对孔隙发育的影响——以川中-川南过渡带须家河组为例

通过岩石(铸体)薄片鉴定、扫描电镜及X射线衍射分析等手段,对川中-川南过渡带须家河组致密砂岩储层石英溶蚀特征、成因机理及对储层孔隙发育的影响进行了详细研究,结果表明:储层中存在大量石英溶蚀现象,石英沿颗粒边缘、颗粒内部、次生加大边等部位进行溶蚀,石英溶蚀主要发生在中成岩A₂亚期;石英溶蚀的成因机制有两种,第一种是碱性成岩环境下的直接溶蚀,溶蚀程度相对较弱;第二种是黏土矿物和碳酸盐矿物的交代溶蚀,其中黏土矿物对石英颗粒交代溶蚀作用较强;石英颗粒溶蚀后形成大量的次生孔隙,有效增加储集空间,改善孔隙结构,提高储层孔渗性能,尤其是黏土矿物交代溶蚀石英后形成的次生孔隙对储层孔隙的贡献较为可观。     

鄂尔多斯盆地长7段致密储层主要黏土矿物特征及其地质意义

鄂尔多斯盆地延长组长7段致密储层表现为强压实、强胶结的致密化特征,其中伊利石、绿泥石等黏土矿物的大量存在是导致储层致密的重要原因。通过铸体薄片、扫描电镜、XRD等测试资料结合沉积、成岩环境分析,研究了长7段致密砂岩储层主要黏土矿物的微观赋存状态,并刻画了宏观分布特征,在此基础上探讨了其形成机理及对储层的影响。结果表明,长7段致密储层黏土矿物中伊利石含量最高,占黏土矿物总量的近60%,其次为绿泥石,占总量的30%以上,高岭石含量较低;受物源区母岩特征、砂岩成因类型、沉积环境、成岩流体性质等因素影响,各种黏土矿物平面分布具有差异性,陇东地区伊利石含量特别高,陕北地区绿泥石和高岭石含量相对较高;黏土矿物对陕北地区长7段致密砂岩最显著的影响表现为绿泥石膜对原生孔隙的保护及高岭石对孔隙的充填;而对陇东地区长7段致密砂岩最显著的影响则表现为伊利石对原生孔隙的普遍充填分割。沉积环境和原生孔隙条件的差异及自生黏土矿物形成过程中物质、流体复杂作用造成现今不同地区长7段致密储层孔隙发育特征的差异,并对开发特征产生影响。     

鄂尔多斯盆地苏里格气田西南部成岩矿物转化与储层物性

成岩矿物的转化是致密砂岩储层物性变化的主要因素之一。为了探索二者之间的关系以及储层致密化成因,采用薄片观测、扫描电镜分析、阴极发光分析等手段,结合成岩演化过程中的矿物热力学特征和体积变化,探讨了苏里格气田西南部山1段、盒8段砂岩的矿物组成、孔隙特征、矿物转化机制及其对储层孔隙的影响。结果表明:①胶结物以黏土矿物、方解石为主,硅质少量;②绿泥石薄膜可包裹高岭石和石英加大边,偶见放射状绿泥石且孔隙较好;③黏土矿物晶间孔占孔隙比重较高,高岭石伊利石化后的晶间孔隙较发育,其次为溶蚀孔隙;④嵌晶状方解石充填剩余粒间孔隙,并交代石英加大边和伊利石,破坏储层物性。认为中成岩A期的钾长石溶蚀、蒙脱石伊利石化、高岭石伊利石化、黑云母水化都会使得矿物体积变小,属于增孔反应,在一定程度上改善储层孔隙;且胶结作用增加储层的抗压实能力,在一定程度上保护了原生孔隙;故在分析胶结作用对物性的影响时,不能简单地归结为破坏性成岩作用。     

黄骅坳陷沧东凹陷孔二段细粒沉积岩中方沸石的发现及其地质意义

通过大量岩石薄片鉴定和X射线衍射全岩分析,首次在黄骅坳陷沧东凹陷孔二段细粒沉积岩和致密砂岩夹层中发现大量自生方沸石。方沸石在显微镜下表现为以纹层状富集为主,局部呈泥—微晶分散状分布,少量呈粉晶或连晶胶结物充填粒间孔隙、粒内孔隙、裂缝及液化脉;宏观上表现为与黏土矿物关系密切,矿物含量此消彼长。这种赋存特征间接指明了方沸石早成岩期非火山物质成因的特点,与该区细粒沉积岩中缺少火山物质相吻合。作为碱性成岩环境下析出的自生矿物,方沸石的富集产出可指示盐碱性的沉积水体环境。同时,其早期胶结可抑制压实作用,保存部分孔隙空间,并在后期易与有机酸发生反应,局部溶蚀形成次生孔隙,对致密储层储集性能的改善具有十分重要的意义。     

胜坨油田三区东营组三段储层特征及分类评价

通过岩心观测、岩心薄片、铸体薄片、扫面电镜及压汞资料分析,对胜蛇油田三区东营组三段储层微观特征进行了分析研究.论述了储层的岩石学特征、成岩作用及孔隙结构特征.认为储层以粉砂岩为主,储层埋藏较浅地,成岩作用较弱,常见压实、胶结和溶解作用,黏土矿物的转化作用也较普遍,属于早成岩期的B亚期;储层发育粒间、粒内及微裂缝3种孔隙...     

松辽盆地大安油田葡萄花油层特低渗储层成岩相特征与孔隙演化

松辽盆地大安油田葡萄花油层特低渗透储层成因及孔隙演化特征缺乏定量的研究。利用铸体薄片、扫描电镜、电子探针、X射线衍射和全岩、物性、压汞等定性、定量资料对葡萄花油层成岩作用类型、成岩相进行定量研究并恢复各成岩相孔隙演化过程。结果表明：大安油田葡萄花油层经历了早成岩A期压实成岩、早成岩B期胶结成岩、中成岩A期溶蚀成岩和胶结交代成岩4个阶段;机械压实、伊利石和混层黏土胶结、碳酸盐胶结破坏原生孔隙,绿泥石和高岭石环边胶结有利于原生孔保存,长石和火山岩屑溶蚀改善物性;大安油田葡萄花油层可划分为长石溶蚀粒内溶孔相、黏土环边胶结残余粒间孔相、硅质胶结粒间溶孔相、方解石胶结晶间微孔相和黏土杂基充填晶间微孔相5种成岩相,各成岩相主要成岩作用类型、成岩强度影响孔隙组合,造成储层的强烈非均质性;长石溶蚀粒内溶孔相和黏土环边胶结残余粒间孔相储层物性最好,是研究区最有利储层。研究成果为大安油田葡萄花油层效益开发和整体建产提供地质依据。     

番禺低隆起珠海组砂岩碳酸盐胶结特征及其对储层物性的影响

为了深化珠江口盆地番禺低隆起的油气地质特征认识,针对碎屑砂岩储层中碳酸盐胶结物发育特征、胶结机制及其对储层物性的影响等问题,采用孔渗分析、薄片鉴定、扫描电镜及X射线衍射等测试手段,对该区珠海组储层砂岩开展了系统的成岩作用研究。结果表明：该区发育同生成岩期、早成岩阶段A期及晚成岩阶段A₁期共3期碳酸盐胶结;同生成岩期发育基底式胶结的方解石及铁白云石,与该时期孔隙流体在弱碱性成岩环境中过饱和析出有关;早成岩阶段A期发育孔隙式胶结的方解石、铁白云石及菱铁矿,该期胶结物质来源包括生物化石骨架颗粒溶解、铝硅酸盐矿物水化作用及早期残余孔隙流体等;晚成岩阶段A₁期发育少量孔隙式胶结的方解石及铁白云石,该阶段末期成岩环境逐步转变为弱碱性-碱性,在较大埋深、较高温压条件下,强烈的水-岩反应释放出Ca²⁺,Fe²⁺及Mg²⁺等离子并进入孔隙流体,导致末期方解石及铁白云石过饱和析出;碳酸盐胶结是导致研究区储层物性变差的主要原因之一,早期方解石及铁白云石包裹碎屑颗粒,充填粒间孔隙,极大地破坏了储层物性,中期孔隙式胶结的方解石、铁白云石及菱铁矿进一步缩减了孔隙空间,晚期碳酸盐胶结见方解石及铁白云石充填粒间孔隙并交代碎屑颗粒,使砂岩进一步致密化。研究结果可为该区有利区带预测及勘探目标评价提供依据。     

鄂尔多斯盆地定边油田长7 致密砂岩储层成岩作用及孔隙演化规律

鄂尔多斯盆地定边油田延长组长7储层石油地质储量丰富,但砂体致密、非均质性强等因素严重制约了油气的有效勘探开发。综合运用铸体薄片、扫描电镜等资料,深入分析研究区储层的岩石组分、孔隙类型、物性特征及成岩作用,将成岩演化事件与地质响应有机匹配建立研究区孔隙演化模型,厘清储层成岩演化及孔隙演化规律,同时对比不同深度成岩作用对孔隙演化规律的影响程度。结果表明,研究区长7储层以长石砂岩为主,主要发育黏土、碳酸盐等胶结物,有效孔隙类型以残余粒间孔、次生溶孔及晶间微孔为主,为典型的特低孔、超低渗透致密砂岩储层。成岩演化过程先后经历快速压实—早期胶结、胶结—早期溶蚀、溶蚀增孔、压实—晚期胶结等阶段,目前处于中成岩A期。压实作用是导致孔隙减小、储层致密的主控因素,平均减孔量为20.40%;胶结作用平均减孔量为14.02%,其中晚期胶结是储层致密的关键因素;溶蚀作用平均增孔量为5.87%,可延缓储层致密过程。长7^1油层段底部与长7^2油层段中部储层压实、胶结作用减孔量相对较弱,溶蚀增孔量相对较大,可作为研究区勘探开发的首要目标。     

阿姆河右岸酸性气田井口冲蚀及对策

中亚土库曼斯坦阿姆河右岸气田群为高含H_2S和CO_2的碳酸盐岩气藏,单井产量高,井口设备均出现了不同程度的腐蚀。初步分析认为其原因是生产过程中仅考虑酸性介质对气井井口的化学腐蚀,而没有考虑气体流速对井口的冲蚀作用,极大地影响了气田的安全生产。为此,通过对节流阀上下游阀道、法兰面均出现明显坑状腐蚀的进一步分析,明确了化学腐蚀和气体冲蚀的交互作用是井口磨损的主要影响因素,气流冲刷腐蚀坑的化学腐蚀产物会加速冲蚀损害;进而借鉴冲蚀与腐蚀运行环境下的多相管流管道的磨损计算理论,计算了该运行环境下的冲蚀极限速度,得到了不同生产工况下节流阀的抗冲蚀流量;最后,根据气田生产情况,针对性地提出了按气井配产要求来选择采气树类型、节流阀通径及类型冲蚀的技术控制策略。此举为气田安全生产提供了工程技术保障。     

山前地区深井超深井套管防磨与减磨技术研究

针对山前地区深井超深井钻井过程中套管磨损严重的问题,在分析套管磨损机理的基础上,开展了山前地区套管防磨与减磨技术研究,基于技术研究成果及应用实践,得到如下结论:1应用Power V等垂直钻井系统控制井眼轨迹,特别是上部井段的狗腿度和井斜,可明显减小侧向力和磨损量,缩短套管磨损时间;2应综合考虑套管磨损率、磨损系数以及钻杆耐磨带本身的磨损量,优选出效果最优的耐磨带;在狗腿度严重的位置,可考虑采用一定数量的橡胶钻杆卡箍来减轻对套管的磨损;3山前地区钻井液采用CX-300减磨剂能够显著降低磨损速率,减轻套管磨损程度,但在不同钻井液体系使用之前应进行优化分析以确定最佳使用量;4在迪那204井使用高密度钻井液体系,全部采用优选的高密度重晶石粉代替铁矿粉作为加重剂,整个钻进过程中未出现钻具及套管磨损,迪那204井易损件消耗量仅为邻井迪那203井的左右,防磨减磨效果非常显著。     

Biodiesel Projects Helpful to Ease Energy Shortage

Nearly 7,000 hectares of biodiesel forest will take shape in the northern province of Hebei in 2008, part of a national campaign to fuel the fast growing economy in a green way. In no more than five years, the Pistacia chinensis Bunge, whose seeds have an oil content of up to 40 percent, will yield five tons of fruit and contribute about two tons of high-quality biological diesel oil, according to the provincial forestry administration.     

State Energy Base Proposed in Inner Mongolia

Experts recently suggested China set up a state energy base in lnner Mongolia Autonomous Region to ease its energy thirst. The survey was co-conducted by senior researchers from the National Development and Reform Commission, Development Research Center of the State Council, Chinese Academy of Sciences and the Ministry of Finance. To plan and establish strategic energy bases at state level is in line with the principle of ＂giving priority to energy saving and diversifying energy consumption with the utility of coal at the core.＂     

Influence of Shale Oil Boom in North America upon nternational Crude Price Flucturation

正Current stituation of shale oil development in the world The US The country is blessed with abundant shale oil resources and had matersed whole sets of theories and technologies needed for their exploration and development after years of practices.According to an assessment of shale oil resources in major countries and regions of the world issued by the U.S.Energy Information Agency(EIA),the US ranks the second in the world with its 6.8 billion tons of technically recoverable shale oil(shale oil in place is about 136.3 tons).About 8plays had been confirmed to have     

A Sintering-resistant Pd/C Composite Catalyst for Ethylbenzene DehydrogenationDeveloped by CAS Institute of Metals

Carbon deposition is a commonplace phenomenon occurringin the catalytic reaction process, in particular inthe system of direct dehydrogenation of ethylbenzene,because the reactant - ethylbenzene molecules on thesurface of metal oxide catalysts are prone to quickly formcarbon deposits, leading to deactivation of catalysts. Recently,the associate research fellow Mr. Liu Hongyangand the research fellow Mr. Su Dangsheng of the StateShenyang Material Science （United ） Laboratory of theInstitute of Metal Research, CAS by taking advantageof the carbon deposition process during direct dehydrogenationof ethylbenzene have ingeniously designeda Pd/C composite catalyst. This catalyst in comparisonwith the traditional commercial carbon nanotubesupported Pd catalyst shows a significantly improved performancein terms of its catalytic activity and sinteringresistantability.     

ZPEB Overseas Markets Keep Steady and Efficient Development

In recent years, Zhongyuan Petroleum Exploration Bureau （ZPEB） has made rapid development in overseas petroleum markets through its integrated reorganization. A new international business plattbrm established, aimed at becoming a highly ranked contractor with international petroleum engineering technology. ZPEB has expanded its business scope and scale, regulated the market structure,     

New Era for China-Brazil Relations

China and Brazil celebrated the 40th anniversary of establishing diplomatic relations between the two countries in July this year. Bilateral relations between China and Brazil have entered a new stage, and experts expect the already extensive cooperation between the two countries to deepen and broaden as Chinese President Xi Jinping made a state visit to Brazil in mid-July, which is his first state visit to Brazil since he assumed the office last year. The visit to China＇s largest trade partner in Latin America is at the invitation of Brazilian President Dilma Rousseff.     

Large Scale Ethylene Production Package Technology SuccessfullyDeveloped by CNPC

The CNPC Group has successfully developed a largescaleethylene production package technology with independentintellectual property rights, which has beensuccessfully applied in the 1.2 Mt/a ethylene revamp andexpansion project at the Daqing Petrochemical Complex（DPC）.     

Recent Advancements in Petroleum E & P Equipments in China

The role of equipments in oil and gas exploration and development had never been attached with so much importance as that in shale oil and gas boom in the U.S. With the help of massive hydraulic fracturing and horizontal drilling techniques, the U.S., the world＇s No. 1 oil importer even started to dream about energy self-sufficiency with its proudly high production of shale oil and gas from several major shale plays in the country. However, what behind this remarkable achievement are powerful multi-stage hydraulic fracturing machinery and smart tools for directional drilling.