多参数物探测量在探测岩溶裂隙上的应用

本文所述工程实例开始设计应用视电阻率测深来探测工程区的岩溶裂隙发育情况。实际工作中,根据电阻率测深时各种参数的变化来进行综合资料解释,发现在测深时随着测量极距的变化而电位差未变这一反常现象,从而判断在该极距范围内为一等势体,改用充电法圈定等势体范围,很好地探明了工程区的岩熔裂隙发育情况。     

Spacecraft potential control aboard Equator-S as a test for Cluster-II

The payload of Equator-S was complemented by the potential control device (PCD) to stabilise the electric potential of the spacecraft with respect to the ambient plasma. Low potentials are essential for accurate measurements of the thermal plasma. The design of PCD is inherited from instruments for Geotail and Cluster and utilises liquid metal ion sources generating a beam of indium ions at several keV. The set-up of the instrument and its interaction with the plasma instruments on board is presented. When the instrument was switched on during commissioning, unexpectedly high ignition and operating voltages of some ion emitters were observed. An extensive investigation was initiated and the results, which lead to an improved design for Cluster-II, are summarised. The cause of the abnormal behaviour could be linked to surface contamination of some emitters, which will be monitored and cured by on-board procedures in future. The mission operations on Equator-S were not at all affected, because of the high redundancy built into the instrument so that a sufficient number of perfectly operating emitters were available and were turned on routinely throughout the mission. Observations of the effect of spacecraft potential control on the plasma remained limited to just one event on January 8, 1998, which is analysed in detail. It is concluded that the ion beam lead to the predicted improvement of the particle measurements even outside the low density regions of the magnetosphere where the effect of spacecraft potential control would have been much more pronounced, and that the similar instruments for the four Cluster-II spacecraft to be launched in 2000 will be very important to ensure accurate plasma data from this mission.     

准噶尔盆地北三台地区侏罗系储层流体包裹体研究

北三台地区侏罗系储层经历了多次构造运动的改造.对研究区11口井101块流体包裹体样品的系统分析结果表明,该区侏罗系储层具有多期次的油气充注特征.流体包裹体的均一温度和油包裹体的荧光颜色(强度)等测试结果表明,研究区侏罗系储层经历过4期热流体活动,捕获了3期油包裹体和1期天然气包裹体,分别对应地质历史时期3次油充注和1次天然气充注过程.3期油包裹体的均一温度分别为40～65,65～80,80～120℃.油包裹体和盐水包裹体均一温度以及盐水包裹体盐度的统计结果表明,第2期和第3期热流体活动占主导地位.结合埋藏史分析可知,油充注发生于燕山期,天然气成藏发生在喜山早期.研究区现今油气与古油气无论在油气组分还是在成熟度方面都存在明显的差异,这种差异性与油气早期成藏后期遭受改造破坏有关.综合研究区烃源岩的生、排烃史,侏罗系储层埋藏史以及构造活动演化史的分析可知,燕山晚期是北三台地区侏罗系储层的主成藏期,燕山晚期充注的油气是现今油气的主要来源.     

莺歌海盆地LD10气田砂岩储层可动流体特征与天然气充注下限

针对近海盆地低渗砂岩气藏含气量较低,物性下限不明显的难题,本文进行了莺歌海盆地LD10气田低渗砂岩储层流体可动性、天然气充注下限及充注过程的研究。结果表明：研究区发育3种类型储层,分别为：(1)强溶蚀-大孔粗喉可动型Ⅰ类储层,质量最好,大孔喉为优势运移通道;(2)弱溶蚀-中孔细喉部分可动型Ⅱ类储层,较高动力下储层可动流体占比高;(3)致密-微孔管束喉道束缚型Ⅲ类储层,发育极少大孔喉,含气饱和度差异较大。大孔喉分布、储层物性是控制低渗储层流体可动性的主要因素。综合考虑储层流体可动性的微观与宏观因素,认为LD10气田低渗砂岩储层气体可动性的孔喉半径下限为0.1μm,渗透率下限为0.125×10^-3μm²,Ⅲ类储层致密,可作为遮挡层。天然气充注动力较低或充注初期,Ⅰ类储层为气藏聚集的有利区;当天然气充注动力充足时,Ⅰ类储层既是优势运移通道,也是气藏的优势聚集区,Ⅱ类储层为有效储层。研究成果对低渗砂岩储层有效性的判别和气藏有利区的预测具有借鉴意义。     

井中激电在西霞矿区的应用

以西霞矿区ZK001孔的井中激电为实例,介绍了井中激电在该矿区的应用效果及推断解释方法。说明井中激电在对地面激电异常验证中可以判断、验证钻孔是否已揭露异常体及异常体的空间展布状况。     

Gas charging history of the Yingcheng Formation igneous reservoir in the Xujiaweizi Rift, Songliao Basin, China

Systematic analysis of fluid inclusions was carried out on 34 samples from the Yingcheng Formation igneous reservoir of the Xujiaweizi rift, Songliao Basin, China. On the basis of petrographic characterization, the results of the microthermometric analyses indicated that the Yingcheng Formation igneous reservoir trapped six clusters of pure aqueous inclusions, and only four of them have the coeval gas-bearing aqueous inclusions been detected in the analyses. So the Yingcheng Formation igneous reservoir experienced four gas charging events during its evolutionary history. Combined with the research results of burial history and cap rocks, the four gas charging events happened during the time interval from 120 to 85 Ma, and every charging time is no more than 10 Ma. The main gas charging is the third, which happened during the time interval from 105 to 95 Ma.     

最优尺度回归在储层孔隙度主控因素分析中的应用

本文以实测物性、粒度分析及铸体薄片鉴定为基础,结合对东濮凹陷濮卫地区沙二-沙四段储层孔隙度影响因素的分析,利用最优尺度回归方法,定量分析了储层孔隙度的主控因素。研究表明,最优尺度回归可以简便快捷地定量分析多因素对孔隙度的重要程度。分析结果显示各类影响因素重要性排序为:含油级别、层位、胶结物含量、储层与膏盐岩位置关系、压实减孔率及分选系数。成岩作用早期,分选性决定了储层的初始孔隙,压实作用是孔隙度减小的最主要的原因;成岩作用中后期,烃类充注是储层孔隙度得以保存的最主要的原因。     

The role of submicrometer aerosols and macromolecules in H2 formation in the titan haze

Previous studies of the photochemistry of small molecules in Titan’s atmosphere found it difficult to have hydrogen atoms removed at a rate sufficient to explain the observed abundance of unsaturated hydrocarbons. One qualitative explanation of the discrepancy nominated catalytic aerosol surface chemistry as an efficient sink of hydrogen atoms, although no quantitative study of this mechanism was attempted. In this paper, we quantify how haze aerosols and macromolecules may efficiently catalyze the formation of hydrogen atoms into H₂. We describe the prompt reaction model for the formation of H₂ on aerosol surfaces and compare this with the catalytic formation of H₂ using negatively charged hydrogenated aromatic macromolecules. We conclude that the PRM is an efficient mechanism for the removal of hydrogen atoms from the atmosphere to form H₂ with a peak formation rate of ∼ 70 cm⁻³ s⁻¹ at 420 km. We also conclude that catalytic H₂ formation via hydrogenated anionic macromolecules is viable but much less productive (a maximum of ∼ 0.1 cm⁻³ s⁻¹ at 210 km) than microphysical aerosols.     

鄂尔多斯盆地上三叠统延长组超低渗储层油气成藏启动压力研究

近10年来,非常规油气资源在全球能源格局中的地位愈发重要,低渗透—致密油已成为目前勘探的热点,在我国具有可观的前景。而对于低渗透油气成藏启动压力的研究一直是一个难点,目前仍处于起步阶段,它的完善直接关系到低渗透乃至致密油气成藏的理论研究及勘探。本文首先以鄂尔多斯盆地延长组岩心为基础进行覆压孔隙度、渗透率实验研究,分析储层物性随覆压的变化关系;其次,结合喉道半径与孔、渗的关系,研究喉道半径随有效应力的变化关系,并探讨不同成藏机制的致密油藏的启动压力;最后详细分析鄂尔多斯盆地华池—合水地区上三叠统延长组长7致密油藏的成藏启动压力及成藏下限。结果表明:超低渗储层的孔、渗与有效应力间存在较好的乘幂关系,拟合函数的系数与地表的物性值相关性较好;喉道半径与孔、渗的相关性较好,与孔隙度呈指数关系,与渗透率呈乘幂关系;对于先致密后成藏类型油气藏来说,以渗透率建立的启动压力计算方法可靠,而先成藏后致密或边成藏边致密类型油气藏,启动压力计算方法还有待深入研究。华池—合水地区延长组长7致密油藏成藏时储层渗透率为0.00473×10-3μm2~0.52832×10-3μm2,平均0.01380×10-3μm2;孔隙度为1.458%~10.851%,平均7.224%;储层的平均喉道半径为0.0033~0.3769μm。该区属先致密后成藏,成藏的实际启动压力为0.0788~13.0022 MPa,平均2.1025 MPa。长7源岩的最大埋深为3000 m,原油的充注压力为6.06 MPa,油藏条件下充注的喉道半径下限为8.576×10-3μm,渗透率下限为0.00486×10-3μm2。