柴达木盆地西南部砂6井第三系沉积相研究

结合前人的研究成果,运用野外地质剖面、测井相标志的研究方法,对柴达木盆地西南第三系沉积相进行了较全面、系统的研究,描述了柴达木盆地砂6井第三系主要发育的三种沉积相及发育的主要类型,指出了研究区内有利于油气生成和储集的沉积相类型。     

甘肃庆城庄19井区上三叠统延长组长82亚油层组 低渗透储层的地质特征

长82亚油层组是甘肃庆城地区庄19井区上三叠统延长组中储集砂岩相对富集的层位,但砂岩低渗透性的特点显著,成为影响该区石油储产量增长的主要地质因素.结合前人的相关工作,通过钻井岩心观察、测井曲线分析、储层岩石实验测试等工作,详细地分析了庄19井区长82亚油层组低渗透储层的地质特征,认为沉积微相和压实作用、胶结作用是控制低渗透性储集砂岩发育和分布的主要地质因素,寻找以水下分流河道微相为代表的有利储集相带砂岩体是油气勘探的重要方向.     

基于免疫粒子群优化算法的影像纹理分类

粒子群优化算法是基于群智能的随机全局优化方法,它源于对鸟群简化社会系统的模拟。为了提高标准粒子群优化算法的收敛性能,将生物免疫系统的记忆能力和多样性引入标准粒子群优化算法,提出一种免疫粒子群优化算法。在提取纹理样本Laws纹理能量模板特征、小波特征等纹理特征的基础上,提出针对分类问题的粒子表达方法和群体寻优策略,实现了基于免疫粒子群算法的纹理分类。实验结果表明,与标准粒子群优化算法相比,免疫粒子群优化算法在获取训练样本类别中心时具有较好的收敛性能,并且基于该算法的影像纹理分类具有较高的分类精度。     

Textural segmentation of digital rock images into bedding units using texture energy and cluster labels

The texture of digital rock images, as recorded, for instance, with borehole imaging devices, is shown to reflect different bedding types. Textural segmentation of borehole images, therefore, subdivides the recorded sequence into bedding units. We show that a textural segmentation algorithm based on the concept of texture energy achieves good results when compared with synthetic as well as real data in which petroleum geologists have performed zonations on cores. Texture energy involves filtering of the original image with a set of texture sensitive masks. The filtering is done as a finite convolution over the size of the masks. On the resulting images the variance is computed over a relatively large sliding window, which, in its practical implementation, covers the full width of the image. The resulting nine one-dimensional curves are then clustered hierarchically into a user-determined number of image texture or lithological bedding classes. Principal component analysis previous to clustering can be used to reduce redundancy in the data. A recurring and relatively ill-defined problem in this field are macro-textures, i.e., the cyclic interbedding of two or more bedding types. We show that sliding Fourier transforms and variable mask scale can successfully address the zonation of macro-textures. In general, the method gives best results with mask sizes equivalent to 2–4 centimeters, reflecting the length scale at which the investigated geological bedding seems to have its highest variation.     

福建石炭纪岩相古地理分析

笔者总结了福建省石炭纪生物地层与岩石地层的研究成果,提出了生物地层与岩石地层的划分对比。在详尽的相分析基础上对该纪地层进行了相系、相、亚相及微相的划分,并按“优势相”的原则分期编制了林地期、黄龙期及船山期的岩相古地理图。笔者采用“相、层、位”控矿观点对石炭纪的矿产成因及成矿规律作了探讨。     

张广才岭南部杨木岗组的厘定及物源分析

本文通过岩石组合特征和区域对比，将张广才岭南部西蛤拉河子—大锅盔一带分布的浅变质地层重新厘定为杨木岗组。为了确定杨木岗组的形成时代和沉积物源，进行了碎屑锆石U- Pb年代学和微体古生物地层学研究。锆石大多数呈自形—半自形晶，显示典型振荡岩浆生长环带，暗示其岩浆成因。该地层中测得的两组碎屑锆石U- Pb产生多组谐和年龄，其中PM010- TW样品56个测点最小峰值(谐和)年龄为307 Ma，DB02- TW样品51个测点最小峰值(谐和)年龄为275 Ma；覆盖在杨木岗组之上的中生代二浪河组安山岩的定年结果为181. 1±0. 9 Ma，表明杨木岗组形成于早二叠世晚期。杨木岗组中获取疑源类化石组合出现了新元古代晚期—早寒武世和奥陶纪地层常见分子，结合碎屑锆石年龄结果，反映杨木岗组沉积时周围存在早古生代和中—新元古代地质体。碎屑沉积岩Al2O3/TiO2平均值为24. 44，稀土元素球粒陨石标准化曲线具有轻稀土富集、重稀土稳定和负Eu异常特征，结合碎屑锆石的年龄频数可以看出，确定杨木岗组的沉积物主要来源于沉积盆地周围的晚古生代早期中酸性火成岩，次要物源由沉积盆地周边的早古生代地质体和近地表的中—新元古代地质体提供。佳木斯地块为松嫩- 张广才岭地块上晚古生代地层的形成提供了部分物源，暗示佳木斯地块与松嫩- 张广才岭地块于早二叠世之前已完成拼合。     

我国藻菌生物成因的金矿研究

生物成矿作用分为生物直接成矿作用和生物间接成矿作用,生物直接成矿作用的标志结构为生物有机胶体结构。生物间接成矿作用的标志结构为“矿交代生物”结构,我国陕西二台子－半仓沟金矿,四川东北寨金矿、川甘拉尔玛金矿和云南金厂金矿等均为典型为实例,矿石中普遍含有多种金属矿物生物结构,还含多种生物有机组分。成矿物质具有多源性特征,硫同位素具混合型特征,矿床成型机制可与“人工碳吸附系统”聚金机制相类比,含金层位可     

High-resolution sedimentary record of lead in the coastal mud of the East China Sea in the past one hundred and fifty years

In the East China Sea （ECS）, there are some mud areas, including the south coastal mud area, the north coastal mud area, and the mud area to the southwest of Cheju Island. X-ray fluorescence （XRF） techniques and Thermal Ionization Mass Spectrometry （TIMS） were used to study the high-resolution sedimentary record of Pb concentrations and Pb stable isotopic compositions in the past one hundred and fifty years in the coastal mud of the ECS. Pb concentrations of a ^210Pb dating S5 core in the study area have increased rapidly since 1980, and reached the maximal value with 65.08 μg/g in 2000, corresponding to the fast economic development of China since the implementation of the ＂Reform and Open Policy＂ in 1978; ^206Pb/^207Pb ratios generally had stabilized at 1.195 from 1860 to 1966, and decreased gradually from 1966 to 2000, indicating that the anthropogenic source Pb contribution to the ECS has increased gradually since 1966, especially since 1980. Pb concentrations decreased distinctly from 2000 to 2003 and ^206Pb/^207Pb ratios increased from 2001 to 2003, corresponding closely to the ban of lead gasoline from 2000 in China. From 1950 to 2003, there occurred four distinct decrease events of ^206Pb/^207Pb, possibly responding to the Changjiang River （Yangtze River） catastrophic floods in 1998, 1991, 1981 and 1954; from 1860 to 1966, there were two decrease periods of ^206Pb/^207Pb, which may respond to the catastrophic floods of Changjiang River in 1931 and 1935, and 1870. As a result of the erosion and drowning by the catastrophic floods, the anthropogenic lead accumulated in soil and water environments over a long period of time was brought into the Changjiang River, then part of them was finally transported into the ECS, which leads to changes in Pb stable isotopic composition.     

吉尔嘎朗图凹陷宝饶洼槽下白垩统层序地层与沉积体系

运用高分辨率层序地层学原理和方法,通过对钻井和地震资料的综合分析,在二连盆地吉尔嘎朗图凹陷下白垩统中识别出1个超长期基准面旋回(二级层序)SSC1和5个长期基准面旋回(三级层序):LSC1,LSC2,LSC3,LSC4,LSC5,分析了各旋回的发育特征。识别出五种类型的沉积体系:滨浅湖近岸水下扇、较深水湖浊积扇、滨浅湖扇三角洲、滨浅湖辫状河三角洲和河流沉积体系,并在等时地层格架内分析了各基准面旋回的沉积体系构成和储层砂体的发育情况。综合分析生、诸、盖条件后认为,在垂向上,LSC3旋回为本区最有利的储集层段,在平面上,本区的油气勘探应主要寻找宝饶构造带辫状河三角洲前缘砂体,主要储层砂体类型为前缘分流水道砂和前缘席状砂。     

纹理映射失真处理中的LOD技术

纹理映射是计算机图形学中广泛应用的一项重要技术,纹理图像可以描述景物表面各点处的反射属性,模拟景物表面丰富的纹理细节,减少建模的工作量,提高计算机生成图形的真实性.但是由于纹理都为栅格图像,放大和缩小会产生一定程度的失真,所以要对纹理进行细节分层处理.文中主要介绍纹理的重采样和建立金字塔技术,提出减少纹理映射失真的方法.