The Origin of Pb-Zn Deposits in the Northern Kuandian Area, Liaoning Province

1 Regional geologyThere are a series of lead -- zinc deposits in theLiao-ji paleo-rift, for exarnple, the Kumduk Pb -- Zndeposit of Korea, the Huanggoushan Pb -- Zn depositof Jilin Province, the Qingchengzi Pb -- Zn dePOsitand Beiwagou Pb -- Zn deposit of…     

碳酸盐岩团簇同位素约束下的川东地区二叠系热演化

有效古温标的缺乏制约了碳酸盐岩层系热史的研究,团簇同位素作为一种新兴古温标,对碳酸盐岩层系热史重建具有重要意义。四川盆地二叠系是天然气勘探开发的重点层系,本文通过对川东地区二叠系碳酸盐岩样品进行团簇同位素测试,联合镜质组反射率重建了二叠纪以来的热史,在此基础上明确了二叠系烃源岩的热演化,并讨论了峨眉山地幔柱对川东热体制的影响。川东地区碳酸盐岩的团簇同位素温度在101. 7~178. 7℃,利用交换/扩散模型进行热史模拟认为：川东地区晚白垩世古温度最高,最高古温度在213~225℃,古地温梯度在23~33 ℃/km;川东地区二叠纪古热流最高,最高古热流约为55~70 mW/m 2,二叠纪之后热流逐渐降低至现今大地热流。烃源岩热演化分析认为：川东地区二叠系烃源岩热演化具有阶段性,热演化受控于构造运动,受印支期运动和燕山 喜马拉雅期运动影响存在两期热演化停滞,晚白垩世达到最高古温度后停止生烃,现今处于生气阶段。川东地区二叠纪热流值和烃源岩热演化主要受到地壳拉张减薄作用的影响,受峨眉山地幔柱的影响较小且具有局限性。     

Geochemical characteristics and geological significance of the Neoproterozoic carbonates from northern Anhui Province,China

Petrographical and geochemical studies were carried out of the Neoproterozoic carbonates from northern Anhui Province, China. These carbonates can be subdivided into two types, including purified limestone (PL) and mixed limestone and siliclastic rocks (MLS). PLs are low in Si, Al, Zr and total REE but high in CaO compared with MLSs. Correlations between Zr, Fe2O3, P2O5 and total REE are also less remarkable, indicating that they were not obviously contaminated by continental materials but directly precipitated from seawater. So they can be used for the inversion of paleo-seawater REE patterns. The inversed results indicated that the REE pattern of Neoproterozoic seawater was similar to that of the modern seawater except for the lack of Ce depletion, which was probably affected by the reduced hydrothermal solution. In combination with previous studies, the geochemical trending of these carbonatic samples towards the continental arc in the La- Th-Sc and Th-Sc-Zr/10 diagrams is interpreted as the contamination of arc volcanism. The tectonic background of the southern margin of the North China Craton in the Neoproterozoic was probably related to the Grenville orogeny during the convergence of the Rodinia supercontinent, rather than an intra-plate environment.     

Geochemical Characterization and Origin of High-Sulfur, Heavy Oils in Jiyang Sub-Basin, East China

High-sulfur,heavy petroleum is widely occurring in the Tertiary lacustrine Jiyang sub-basin, Bohai Bay Basin.They are differentiated into two families based on the bulk properties and biomarker compositions.Family 1 is characterized by high resins(40%-71%)and sulfur(2%-4%),and low wax (l%-6%),with n-alkanes removed by biodegradation,whereas family 2 is characterized by extremely abundant sulfur(3%-10%),and high asphaltenes(7%-31%)and wax(2%-19%),with no evidence of microbial attack.The oils of family 1 a...     

塔中隆起带断裂系统及其对碳酸盐岩台地的控制

碳酸盐岩台地的建造与改造受多种因素的控制,本文主要探讨以断裂活动为代表的构造运动对碳酸盐岩台地发育和破坏的控制作用。塔中地区主要发育NW向基底卷入式断裂系统和NE向盖层滑脱式逆冲断裂系统两大类,前者主要形成于早奥陶世末的中加里东I幕构造运动,该断裂控制了塔中隆起开始形成时的构造格局,从而使塔中隆起带碳酸盐岩台地由早期的缓坡-镶边缓坡型的台地结构演化为礁滩型孤立台地,而后者主要形成于晚奥陶世末中加里东II幕构造运动,该断裂的强烈活动,使得塔中地区发生东西翘倾运动,东部隆起接受改造,早期的碳酸盐岩台地遭受严重破坏。     

川东地区华蓥山海相三叠系不同类型岩石对海水信息的保存性评估

通过对川东地区华蓥山海相三叠系不同岩石类型样品的微观组构、阴极发光和微量元素等分析表明:川东地区华蓥山海相三叠系不同的岩石类型样品具有不同的抵抗成岩蚀变能力,其对海水信息的保存程度也不一致;钙质泥岩所记录的有关信息已基本不能代表海水,多数微晶灰岩所记录的有关信息可以较好地代表海水,而粉晶白云岩只有部分样品可以代表海水的...     

贵州湄潭地区土壤中钙、镁含量与茶叶生长关系研究

本文对贵州湄潭碳酸岩分布区岩石、土壤中钙、镁元素含量分布及其对茶叶生长的影响进行了调查研究,结果表明岩石中钙、镁元素的含量决定着土壤中钙、镁元素的含量,土壤中钙、镁元素的含量决定着土壤溶液中Ca2＋、Mg2＋的含量,并直接影响土壤pH值的高低。调查测试结果还表明,调查区适宜茶叶种植的土壤pH高极限值为6.0,土壤交换性...     

陆表海碳酸盐岩台地沉积期微地貌恢复方法研究——以四川盆地磨溪气田嘉二2亚段A层为例

陆表海碳酸盐岩台地沉积期微地貌起伏差异小,难于确定。分析了沉积期微地貌控制着颗粒滩储层的发育及分布,因此,可通过对颗粒滩储层的研究,反演微地貌起伏。按此原理,建议具体研究步骤为:颗粒岩沉积为主体的等时地质体选取、储层成因确定、暴露时间确定、沉积期地貌恢复,以及成果检验应用。以四川盆地磨溪气田嘉陵江组嘉二2亚段A层为例,利用丰富的钻孔取心资料进行了实例研究,取得良好效果,表明该方法值得推广应用,尤其适用于钻探程度高、资料老、缺乏三孔隙度测井系列的盆地老区,这对于储层预测和新层挖潜具有重要参考意义。     

塔河油田12区块奥陶系裂缝分布规律研究

通过对露头、铸体薄片、岩性分析和成像测井资料观察和分析发现,塔河油田12区块奥陶系储层内缝洞发育,并且裂缝在一间房和鹰山组的储层中起了至关重要的作用,它既是地层流体的存储空间,又是连通孔洞缝的主要通道。裂缝的发育也增加了储层的非均质性。所以,精细研究裂缝的发育和分布规律,并定量地计算裂缝的相关参数对于识别奥陶系储层和对...     

碳酸盐岩系有机氮与无机氧热化学交换作用研究

深埋碳酸盐岩储层中的水与金属氧化物可能会影响到吡咯类含氮化合物的保存。对吡咯—水—氧化铝反应体系进行了热模拟实验研究,根据模拟实验结果,探讨了反应机理,并考察了反应的动力学特征。结果表明,吡咯—水—氧化铝体系可以发生反应,产物主要为呋喃与氨气,升高温度对反应有利。氧化铝对有机氮与无机氧热化学交换作用起到了明显的催化作用...