天然气氦同位素分布与大地构造环境

根据中国大陆主要含油气盆地天然气的＾３Ｈｅ／＾４Ｈｅ数据，首次系统研究了天然气中氦同位素空间分布与中国大地构造环境的关系。中国东部滨太平区＾３Ｈｅ／＾４Ｈｅ平均值Ｒ＝２．０８×１０＾－５＞Ｒａ，为含幔源氦的二元混合型氦；中西部区的Ｒ＝４．９６×１０＾－８，基本为地壳一元放射型氦；华北－中原区的Ｒ＝８．００×１０＾－７，为介于东与中西部之间的过渡型氦。整体而言，＾３Ｈｅ／＾４Ｈｅ值呈自东而西随远离西     

龙门山前陆盆地南段乐地1井须家河组震积岩特征及地质意义

通过对龙门山前陆盆地南段乐地1井上三叠统须家河组岩心的系统观察和描述,以前人对震积岩的研究为基础,探讨震积岩的分布特征以及与盆地构造活动的关系。震积岩主要分布在须家河组第二、第三和第四段,发育典型的由地震导致的软沉积物液化变形和脆性变形构造,包括液化砂岩脉、液化卷曲变形与混滑层、负载构造及球枕状构造、环形层理、震裂岩和微断层。认为这些软沉积物液化变形和脆性变形构造是由龙门山隆升构造引起的地震作用形成的。乐地1井中地震岩的分布特征表明龙门山前陆盆地南段在须家河组第二、第三和第四段时期构造活动强烈,并快速向南东方向推进。     

On-off intermittency in continuum systems driven by Lorenz system

Previous studies of on-off intermittency in continuum systems are generally in the synchronization of identical chaotic oscillators or in the nonlinear systems driven by the Duffing oscillator. In this paper, one-state on-off intermittency and two-state on-off intermittency are observed in two five-dimensional continuum systems, respectively. The systems have skew product structure in which a two-dimensional subsystem is driven by the well-known Lorenz chaotic system. Moreover, the phenomenon of intermingled basins is observed below the blowout bifurcation. The statistical properties of the intermittency in the systems are investigated. It is shown that the distribution of the laminar phase duration time follows a power law, and that of the burst phase amplitude shows a −1 power law, which coincide with the basic statistical characteristics of on-off intermittency.     

东北地区典型水库控制流域径流变化及驱动因子分析

结合3种趋势检验及模糊直接识别法对水文要素变化进行分析.以东北地区9个水库控制流域的气象、水文数据及土地利用情况为基础,重点分析了径流变化及其驱动因子降雨、降雨年内分布、蒸发及土地利用等变化情况.根据径流及其他因子的变化特征将研究水库流域归类成气候变化显著型(汤河、碧流河、观音阁及葠窝水库流域)、土地利用变化显著型(闹德海及丰满水库流域)及自然状况较好型(白山、桓仁及大伙房水库流域),继而对各类流域分别有针对性地提出变化深入分析方法及水库运行管理建议,最终为东北水库流域典型水文变化的深入研究奠定基础.     

东秦岭-大别造山带南缘印支期以来构造层序耦合特征分析

通过对东秦岭-大别山造山带南缘鄂东地区、荆当盆地、秭归盆地和川东北地区三叠纪-古近纪的构造层序对比研究,划分出三个大的构造层序,并分析了中上扬子地区印支期以来沉积盆地性质转换和迁移过程与构造层序的耦合关系,揭示了东秦岭-大别造山与成盆作用过程.认为早三叠世至中三叠世构造层序Ⅰ记录了扬子地台由克拉通盆地逐渐萎缩的过程,反映了印支期华北板块与扬子板块之间软碰撞未造山的过程;晚三叠世至早白垩世构造层序Ⅱ记录了前陆盆地的三次幕式演化过程,反映了早燕山期华北板块与扬子板块之间呈斜向、剪刀式由东向西陆-陆碰撞关闭以及前展逆冲叠置造山作用过程,与江南逆冲带联合作用形成前陆盆地沉降和沉积中心向西的迁移.晚白垩世至古近纪区域构造背景发生重大变化,构造层序Ⅲ记录了晚燕山期地壳快速均衡隆升,伸展断陷盆地形成演化过程.     

特低渗砂岩储层微观结构及孔隙演化定量分析

为了表征鄂尔多斯盆地姬塬地区长4+5油层组低孔特低渗长石砂岩的孔隙结构,进一步探讨孔隙演化及其控制因素,通过铸体薄片、扫描电镜、高压压汞、X线衍射、粒度分析及物性等资料,分析总结出5种孔隙类型和4种喉道类型;结合成岩作用研究,采用定性分析与定量计算的方法分析孔隙演化过程.研究区储层孔隙以粒间孔、长石溶孔和粒间溶孔为主,发育点状、缩颈状和片状喉道,喉道具有细喉和微细喉的特点.成岩缝的发育改善储层的渗透性,相互连通的微裂缝网络是流体运移的最佳通道.运用未固结砂岩原始孔隙度与砂岩的分选系数的统计关系,恢复计算出研究区砂岩原始孔隙度平均为34.60％.在成岩过程中,机械压实作用和胶结作用对储层孔隙具有中等程度破坏作用,受二者影响,未固结砂岩49.4％的原生粒间孔被压实损失,28.7％的孔隙被胶结破坏.区内溶蚀作用较发育,溶蚀强度中等,并形成大量次生孔隙,使得孔隙度增加到11.33％,溶蚀作用的孔隙增加率为11.0％,极大地改善低孔特低渗砂岩储层的储集空间.定量计算结果与定性认识的一致性以及与室内物性测试结果的吻合性表明:研究方法与结论可靠,这对于同类储层孔隙演化的研究具有借鉴意义.     

Classifying cellular automata automatically: Finding gliders,filtering, and relating space‐time patterns,attractor basins,and the Z parameter

Cellular automata (CA) rules can be classified automatically for a spectrum of ordered, complex, and chaotic dynamics by a measure of the variance of input‐entropy over time. Rules that support interacting gliders and related complex dynamics can be identified, giving an unlimited source for further study. The distribution of rule classes in rule‐space can be shown. A byproduct of the method allows the automatic “filtering” of CA space‐time patterns to show up gliders and related emergent configurations more clearly. The classification seems to correspond to our subjective judgment of space‐time dynamics. There are also approximate correlations with global measures on convergence in attractor basins, characterized by the distribution of in‐degree sizes in their branching structure, and to the rule parameter, Z. Based on computer experiments using the software Discrete Dynamics Lab (DDLab), this article explains the methods and presents results for 1D CA. © 1999 John Wiley & Sons, Inc.     

松辽盆地古龙地区葡萄花油层油气成因与凝析气藏形成分布

重点以轻烃和生物标志物综合研究了松辽盆地北部古龙地区葡萄花油层凝析油气、轻质油气的来源与成因。结果表明该区油气(葡萄花油层)主要与齐家—古龙凹陷青山口组高熟腐泥型烃源岩有关,而一些轻质油气还存在姚家组泥岩局部成烃的贡献。最后论述了该区葡萄花油层凝析气藏的形成与分布规律。     

ADVECTION–DIFFUSION PROCESSES AND RESIDENCE TIMES IN SEMIENCLOSED MARINE BASINS

This paper addresses the problem of estimating the residence times in a marine basin of a passive constituent released in the sea. The dispersion process is described by an advection–diffusion model and the hydrodynamics is assumed to be known. We have performed the analysis of two different scenarios: (i) basins with unidirectional flows, in three space dimensions and under the rigid lid approximation, and (ii) basins with flows forced by the tide, under the shallow water approximation. Let the random variable τ be defined as the time spent in the basin by a particle released at a given point. The probability distribution of τ is obtained from the solution of the advection–diffusion problem and the residence time of a particle is defined as the mean value of τ. Two different numerical approximations have been used to solve the continuous problem: the finite volume and Monte Carlo methods. For both continuous and discrete formulations it is proved that if all the particles eventually leave the basin, then the residence time has a finite value. We present here the results obtained for two study cases: a two- dimensional basin with a steady flow and a one-dimensional channel with flow induced by the tide. The results obtained by the finite volume and Monte Carlo methods are in very good agreement for both scenarios.     

塔里木盆地克深前陆冲断带储层岩石力学参数研究

综合采用岩石单轴压缩试验、三轴压缩试验及测井资料计算,对塔里木盆地克深前陆冲断带单井的岩石力学参数进行分析,通过单轴-三轴校正及动态-静态校正,确定静态岩石力学参数的单井剖面,利用高斯插值对岩石力学参数空间分布特征进行研究,并分析岩石力学参数与地层深度的关系。结果表明:岩石力学参数的空间分布主要与岩相有关,并在一定程度上反映了储层物性特征,弹性模量、内聚力和抗压强度大而泊松比小的区域储层物性相对更好;随着地层深度的增加,弹性模量、内聚力和抗压强度逐渐增加而泊松比逐渐下降;利用岩石力学参数与地层深度的关系以及断层带岩石力学参数的经验比例,可以对不同地质单元的岩石力学参数进行取值,为后续的地应力场及储层裂缝数值模拟奠定基础。