试论碳酸盐岩中一种新的颗粒类型——成岩颗粒

本文讨论了沉积作用后多种成岩作用形成的一些碳酸盐颗粒的新类型。球粒、内碎屑、团块、角砾、异形粒等都可以由同生-成岩作用或纯成岩作用形成。正确认识成岩颗粒可以帮助恢复成岩条件和成岩发展史。     

长江下游火山岩的二个变异趋势及其形成机制

长江下游地区若干盆地不同旋回火山岩的化学成分存在２个不同的变异趋势，即富硅趋势和富钾趋势。富硅趋势主要由分离结晶作用形成的。富钾趋势的成因较为复杂。庐枞富钾趋势的形成与分离结晶作用有关，溧水富钾趋势涉及分离结晶与混染作用。而宁芜富钾岩石是由独立的母岩浆形成的。     

嵌岩（软岩）桩轴向荷载传递机理的弹粘塑性分析

本文采用弹－粘塑性力学模型，用有限元法对设置于软岩中的嵌岩桩轴向荷载传递机理进行了数值分析，以Ａｋａｉ等人对软岩三轴排水蠕变试验得出的关于软岩具有明显速敏性和剪胀性的结构论为基础，结合Ｐｅｒｚｙｎａ理论以及Ｃｌｏｕｇｈ－Ｄｕｎｃａｎ非线性界面单元模拟桩－岩接触面的相互作用，从而作了能反映嵌岩桩桩蠕变沉降性状的岩土力学模型。数据分析结果表明，桩侧阻力是嵌岩桩承载力的主要组成部分；软岩蠕变性的强弱对嵌     

高压半渗透隔板仪的研究

本文介绍了一种用国产材料研制的GBY-1型双岩芯室高压半渗透隔板仪。从国内工厂所研制的13种隔板中挑选出气驱水突破压力为7bar的冲压烧结陶瓷隔板,它适用于10md以上的油气储集岩岩样,所测得的毛细管压力—水饱和度关系曲线更为逼近油层条件,且具有不污染样品,测试精度高,重复性好等优点。目前已由江苏海安石油科研仪器厂批量生产。     

东营凹陷纯西辉长岩-变质岩组合油藏成藏机制

目的探讨纯西辉长岩-变质岩油藏的形成演化过程。方法在查明纯西辉长岩活动时间及其高温、高压持续时间的基础上,结合纯西地区的构造发育史、周围洼陷的生烃史及油气分布规律,对其周围烃源岩的岩性、岩相及有机地球化学等进行了分析。结果建立了纯西辉长岩-变质岩组合油藏的成藏模式。结论辉长岩不仅大大促进了周围烃源岩的生烃、排烃过程,而且将其改造成为变质岩储层,并最终形成了特殊的辉长岩-变质岩组合油藏。     

Coesite eclogite facies metamorphic tectonite: Evidence for ultrahigh pressure deformation

An ultrahigh pressure ductile shear mélange crops out on the beach of Yangkou Bay near Qingdao City. The mélange is composed of weakly deformed blocks in a highly ductilly flow mylonites. Ultrahigh pressure metamorphic (UHPM) tectonite includes strongly deformed eclogite and mylonitized eclogite. Coesite occurs in the tectonite as both interstitial mineral and inclusions in garnet and omphacite, indicating that the deformation took place in the stability field of coesite (800—850℃, >30 GPa) in the upper mantle. Coesite is rounded or short prismatic grains with undulatory extinction, and often fractured, suggesting brittle deformation. Garnet is also characterized by brittle fractures and sometimes necked and slightly elongated. Omphacite is elongated, with long axis preferred orientation. Undulatory extinction, subgrains and dynamically recrystallized grains suggest plastic flow of omphacite. Ultrahigh pressure metamorphic tectonite was probably formed in the ductile shear zone during the early stage of exhumation of the ultrahigh pressure metamorphic rocks. Its kinematic indicators point to the transport direction of the UHPM slab during the early stage of exhumation.     

Potash-rich volcanic rocks and lamprophyres in western Shandong Province: 40Ar39Ar dating and source tracing

Highly precise 40Ar39Ar dating results demonstrate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7-124.3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (87Sr/86Sr)i ratios ( 0.708715-0.711418)and distinctly negative εNd values ( -11.47 - -17.54), and are enriched in radiogenic lead (206Pb/204pb=17.341-17.622,207pb/204Pb=15.525-15.538, 208Pb/204pb = 37.563-37.684).Similarly, the lamprophyres also have quite low εNd values ( -11.57 - -19.64). Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings,and extensive comparisons of the Sr, Nd isotopic compositions with that of the related simultaneous rocks, it is concluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting of enriched mantle which was caused by source contamination and metasomatism of subducted continental crustal materials.``     

Reservoir characteristics and genesis of high-porosity and high-permeability reservoirs in Tarim Basin

Based on detailed studies, this paper proposesthat in the Tarim Basin, hydrocarbon reservoirs widespreadeither in vertical sequences or in plane and high-porosity andhigh-permeability reservoirs are developed all over the basin.However, obvious difference and heterogeneity exist amongdifferent kinds of reservoirs. The lithologic characteristics,reservoir space types and reservoir properties in variousstrata have been probed. The result indicates that althoughthe Paleozoic carbonates have been deeply buried for a longperiod, high-quality reservoirs with the porosity of up to 5%—8% (12% as the maximum) and the permeability of10×10^-3—100×10^-3 μm² (1000×10^-3 μm² as the maximum)can be found in certain areas. These include the area withthe development of reefs and carbonate beaches, the weath-ered-crust buried-hill belts that have undergone thelong-term exposure, weathering and leaching, the area withthe development of dolomitization, and those areas that haveexperienced the resolution of carbonic acid and organic acidgenerated by the maturity of the organic matter. Finally, thegenesis of the high-porosity and high-permeability reservoirsin deep-buried conditions (with the depth more than 3500 m)have been investigated thoroughly.     

河北省丰宁地区两类碱长花岗质岩石

冀北丰宁地区的小坝子潜流纹岩、黑山咀流纹斑岩、老虎沟门花岗岩和窟窿山花岗岩是空间上紧密共生、生成时间相近和矿物组成相似的碱长花岗质岩石，也是华北地区中生代晚期岩浆作用的代表性产物。本文报导了这些岩石的地质学、岩相学的岩石地球化学资料，比较了它们的异同，探讨了物质来源问题，提出它们可以划分为两种成因类型，即一类来源于较浅部的、以火成表壳岩为主的变质物质、另一类为较深部的火成物质的观点。     

Geochronology of source materials from high-pressure and ultrahigh-pressure metamorphic rocks in Jurassic sedimentary rocks of Hefei Basin

Eclogite cobbles were discovered by Wang et al. (2001) in the Fenghuangtai Formation of the northern margin of Dabie Mountains in the Dushan area of Anhui Province, China[1]. They proposed that after the formation during the Triassic, the high-pressure (HP) and ultra-high-pressure (UHP) metamorphic rocks reached the sur-face through exhumation and uplifting before the late Ju-rassic. However, they have not provided any evidence about isotopic ages. One kind of cobbles of HP-UHP rocks w…