大庆长垣外围特低渗透扶杨油层CO_2非混相驱油试验研究

大庆长垣外围有3×108t特低渗透的扶杨油层储量在注水开发条件下难以有效动用,为提高这部分储量的有效动用率,开展了CO2非混相驱油试验研究。PVT测试结果表明,扶杨油层原油较稠,体积系数小,膨胀性和收缩性小,溶解系数较低;CO2驱油细管实验最小混相压力为29 MPa,比原始地层压力高8.6 MPa,现场试验为非混相驱;长岩心实验CO2驱油采收率比注水高4~6个百分点。综合室内可行性评价实验结果看,大庆长垣外围扶杨油层开展CO2驱油试验是可行的,并于2003年初在宋芳屯油田南部开辟了注气试验区,有注气井1口,采出井5口。矿场试验结果表明,CO2驱油能够使特低渗透、裂缝不发育的扶杨油层建立起有效驱动体系,从根本上改善其开发效果,该技术有望成为特低渗透扶杨油层有效动用的可行技术。     

全新世岱海流域化学风化及其对气候事件的响应

通过对岱海 12.08 m沉积岩芯 210Pb和 AMS- 14C精确定年及地球化学、物理指标的综合分析,重建了包括 8.2 ka冷期、中世纪暖期 (MWP)和小冰期 (LIA)等典型气候事件在内的全新世以来所经历的化学风化及其环境演化过程.全新世早-中期 (9.0～ 3.5 ka),岱海流域处于温暖湿润气候环境,主要环境特征表现为流域化学风化显著增强、生物生产力逐步提高、湖泊水位大幅度抬升.在 7.90～ 8.25 ka期间存在一次冷气候事件,其发生时间与来自湖沼、海洋、生物组合和极地冰芯等在内的全球环境记录基本一致,具体表现为流域化学风化减弱、湖泊生产力降低以及湖泊水位下降. 2.5 ka以来,岱海沉积物中环境指标的显著变化,表明进入气候波动更频繁的新冰期.岱海沉积物中的指标变化也展示了本世纪以来的气候增暖过程,但其化学风化强度还没有达到 MWP的程度.     

东昆仑山香日德南部白沙河岩组的岩石组合特征和形成年代的锆石Pb-Pb定年启示

柴达木盆地南缘香日德南部金水口岩群白沙河岩组的岩石组合自下而上为长英质片麻岩-钙质片麻岩 斜长角闪岩-大理岩组合.白沙河岩组和侵入该岩组的变质花岗岩的锆石逐层蒸发Pb-Pb定年结果表明:白沙河岩组的陆源碎屑来自一个具有2.1～1.9 Ga岩浆变质热事件的陆源区,当考虑现有的年龄资料时,该岩组的形成年龄可进一步约束在1.6～1.0 Ga间;柴南缘的晋宁期深成侵入活动可能推前到中元古代末.     

贵州早二叠世海相碳酸盐岩稳定同位素组成与玄武岩浆喷发热事件的关系

本文详细讨论了贵州织金地区早二叠世第一旋回海底喷发玄武岩浆对海相碳酸盐岩的碳、氧、锶同位素组成的影响,这主要表现为玄武岩浆喷发热事件导致了碳酸盐岩的δ~(1(?))C、δ~(18)O及~(87)Sr/~(86)Sr值的明显下降。     

国内震积岩研究现状

地震是一种灾害性的地质事件。震积岩是在地层中具有古地震事件纪录的一类岩石的总称。对其研究可为地壳构造演化提供动力学解释。在地震过程中,震积作用可以形成特殊的标志性特征:如震动液化泥晶脉;微褶皱;层内阶梯状断层;自碎角砾岩(震塌岩);液化均一层等。本文综述了国内学者建立的几种陆相和海相震积岩序列:如碳酸盐岩振动液化地震序列(海相序列);大陆边缘震积岩序列;萨布哈震积岩序列(海陆过渡带序列);陆相碎屑岩地震液化序列(陆相序列)。同时,结合国内学者的研究成果,建立了由震积岩、海啸岩和震浊积岩组成的四种地震沉积组合;并指出了震积岩在构造演化解释、石油储层地质及全球古地震节律方面的研究意义。     

离子色谱法测定水样中S~(2-)、SO_3~(2-)、SO_4~(2-)、S_2O_3~(2-)

该种方法利用离子色谱仪的电导检测器与电化学检测器串联 ,十几分钟即可连续完成水中S2 - 、SO2 - 3 、SO2 - 4、S2 O2 - 3 的测定 ,方法具有快速、高效、方便、灵敏、选择性好等特点。方法的检出限分别为 :S2 - 12 5 μg/L ;SO2 - 3 2 2 4 μg/L ;SO2 - 45 0 μg/L ;S2 O2 - 35 0 μg/L。相对标准偏差在 1 5 %～ 6 9%之间 ,能够满足水中S2 - 、SO2 - 3 、SO2 - 4、S2 O2 - 3四种阴离子分析测试的需要。     

Supercritical gas sorption on moist coals

The effect of moisture on the CO₂ and CH₄ sorption capacity of three bituminous coals from Australia and China was investigated at 55 °C and at pressures up to 20 MPa. A gravimetric apparatus was used to measure the gas adsorption isotherms of coal with moisture contents ranging from 0 to about 8%. A modified Dubinin–Radushkevich (DR) adsorption model was found to fit the experimental data under all conditions. Moisture adsorption isotherms of these coals were measured at 21 °C. The Guggenheim–Anderson–de Boer (GAB) model was capable of accurately representing the moisture isotherms over the full range of relative pressures.Moist coal had a significantly lower maximum sorption capacity for both CO₂ and CH₄ than dry coal. However, the extent to which the capacity was reduced was dependent upon the rank of the coal. Higher rank coals were less affected by the presence of moisture than low rank coals. All coals exhibited a certain moisture content beyond which further moisture did not affect the sorption capacity. This limiting moisture content was dependent on the rank of the coal and the sorbate gas and, for these coals, corresponded approximately to the equilibrium moisture content that would be attained by exposing the coal to about 40–80% relative humidity. The experimental results indicate that the loss of sorption capacity by the coal in the presence of water can be simply explained by volumetric displacement of the CO₂ and CH₄ by the water. Below the limiting moisture content, the CO₂ sorption capacity reduced by about 7.3 kg t^− 1 for each 1% increase in moisture. For CH₄, sorption capacity was reduced by about 1.8 kg t^− 1 for each 1% increase in moisture.The heat of sorption calculated from the DR model decreased slightly on addition of moisture. One explanation is that water is preferentially attracted to high energy adsorption sites (that have high energy by virtue of their electrostatic nature), expelling CO₂ and CH₄ molecules.     

Geochemical Characteristics of Granitoids of the Erdenet Porphyry Copper Deposit, Mongolia

Abstract. The Erdenet porphyry copper deposit is one of the major mineral deposits in Mongolia. The geochemical data of granitoids acquired for the Erdenet and its surrounding areas are re-examined. The granitoids of the Erdenet deposit with hypogene type mineralization show the lowest TiO₂ content. Although Ti was possibly lost through the pyritization, it is also possible that the hypogene type mineralization occurred accompanied with the most differentiated granitoids. The variation of the element contents related to the mineralization of the Erdenet deposit shows the decrease of MgO and CaO contents, rather constant K₂O content, rather constant to decrease of Na₂O content, with respect to the Cu contents. The rather constant Na₂O in the mineralized zone is owing to the residual albite against the sericitic alteration. The granitoids of the Erdenet area show an increase of Na₂O content and a decrease of K₂O content with an increase of SiO₂ content. This trend makes clear contrast to granitoids in the surrounding areas. The granitoids of the Erdenet area might have the adakitic nature based on the Sr and Y contents.     

湖南黄沙坪铅锌矿床内带铁闪锌矿铁占位机制的探讨

对黄沙坪铅锌矿床内带铁闪锌矿的研究表明,其形成温度为３００℃±压力大致为１０＾７Ｐａ,成矿溶液为中偏酸性,硫逸度较高,还原性较强,成矿溶液中Ｆｅ和Ｚｎ的主要配合物有：ＦｅＣｌ＾＋,ＦｅＯＨ＾＋,ＦｅＣｌ＾０,Ｚｎ（ＨＳ）＾０２,ＺｎＣｌ＾＋,ＺｎＣｌ＾０２,Ｆｅ＾２＋等,Ｆｅ＾２＋主要是铁闪锌矿结晶过程中进入八面体位置的,这是ＺｎＳ与ＦｅＳ之间构成有限固溶体的根本原因。     

泥盆系弗拉阶/法门阶之交事件沉积和海平面变化

在华南板块南部被动大陆边缘和西伯利亚板块南部活动大陆边缘弗拉阶/法门阶之交识别出7种物理事件相: 细粒钙屑浊积岩相、钙质角砾岩相、软变形灰岩相、含微球粒的粒泥灰岩相、凝灰质砾岩相、黑色页岩相和火山喷溢相.它们在法门阶下Palmatolepis triangularis带底部和/或上Palmatolepis rhenana带底部具有广泛的分布, 可能是两次陨击事件记录, 是良好的高分辨率年代地层对比标志.弗拉期/法门期之交的海平面变化不具有同步性和一致性, 可分辨出2种型式(阶跃型和渐进型) 和5种状态(弗拉期最末期下降→法门期最初期上升、弗拉期最末期上升→法门期最初期下降、弗拉期最末期上升→法门期最初期上升、弗拉期最末期下降→法门期最初期下降、弗拉期最末期与法门期最初期海平面变化不明显).弗拉阶/法门阶之交生物的阶梯状绝灭可能与从上Palmatolepis rhenana带底部至Palmatolepis crepida带不均匀分布的6次陨击事件密切相关.