动态大地测量的平差基准

从平差基准的基本概念出发 ,说明动态大地测量的平差基准的意义和基准的数量 ,讨论动态高程系统的转换关系 ,建立等价于原观测值的坐标差与速率差的观测方程及基准方程 ,并通过分析说明 ,四维大地测量平差必须恰当地选取平差基准 ,才能得到具有参考价值的结果。     

四川盐边、攀枝花基性-超基性岩体中斜长石红外光谱变化特征

本文着重讨论了四川盐边及攀枝花基性-超基性岩体中斜长石红外光谱的变化规律和特征。和前人资料做比较,探讨了谱带位置与光学法、X光法、化学分析所测得的An百分含量的关系;谱带位置与化学分析所得的Si、Al、Ca、Na原子系数之间的关系。     

开平煤田构造发育规律对煤层赋存的影响

依据开平煤田地质勘查和矿井开采资料,并结合前人的研究成果,在系统分析地质构造展布规律和组合特征的基础上,选取NW向剖面作为平衡剖面,采用平衡剖面方法,对煤田构造变形及其对煤层赋存影响进行了研究。研究表明：开平煤田标志层缩短率为e=～23．5％,地层变形程度总体自NW—SE减弱;唐山推覆构造巾间后屯断层与FV断层所夹岩体变形更为强烈,缩短率达到42．9％;开平向斜NW翼地层陡倾甚至倒转,煤层韧性流变和脆性流变广泛发育,唐山矿FⅢ断层上部煤层形成不协调褶皱,局部煤层形成煤仓。     

A Strain Rate Dependent Constitutive Model for the Lower Silurian Longmaxi Formation Shale in the Fuling Gas Field of the Sichuan Basin,China

Shale, as a kind of brittle rock, often exhibits different nonlinear stress-strain behavior, failure and time-dependent behavior under different strain rates. To capture these features, this work conducted triaxial compression tests under axial strain rates ranging from 5×10?6 s?1 to 1×10?3 s?1. The results show that both elastic modulus and peak strength have a positive correlation relationship with strain rates. These strain rate-dependent mechanical behaviors of shale are originated from damage growth, which is described by a damage parameter. When axial strain is the same, the damage parameter is positively correlated with strain rate. When strain rate is the same, with an increase of axial strain, the damage parameter decreases firstly from an initial value (about 0.1 to 0.2), soon reaches its minimum (about 0.1), and then increases to an asymptotic value of 0.8. Based on the experimental results, taking yield stress as the cut-off point and considering damage variable evolution, a new measure of micro-mechanical strength is proposed. Based on the Lemaitre’s equivalent strain assumption and the new measure of micro-mechanical strength, a statistical strain-rate dependent damage constitutive model for shale that couples physically meaningful model parameters was established. Numerical back-calculations of these triaxial compression tests results demonstrate the ability of the model to reproduce the primary features of the strain rate dependent mechanical behavior of shale.     

辽宁红阳煤田控煤构造与深部煤炭资源潜力

针对辽宁红阳煤田局部采区浅部煤炭资源逐渐枯竭的问题,通过煤田构造发育规律和演化史研究、油气地震勘探资料解译、平衡剖面恢复等技术和方法,预测了该煤田深部及外围煤炭资源的赋存状况、远景勘探开发区及煤炭资源量。结果显示:煤田二区为正常背斜的控煤构造,-1500m以浅的煤炭资源储量为83148万t;煤田南部岳家堡背斜往南发育,徐往子勘探区东部存在一个低次序含煤向、背斜构造,可作为远景勘探区,估算-1500m以浅的煤炭资源量为1.85亿t。      

松辽盆地湖泊浅水三角洲沉积动力学研究

本文在充分利用开发检查并全井段取芯,研究沉积微相类型的基础上,结合密集开发井网的动态资料,分析了各种砂体在进间的连通性与平面上的分布规律,系统总结了地形、河流与湖泊大小、气候演化与湖面升降对湖泊浅水三角洲沉积动力学过程及其前缘砂体内部结构、沉积模式的影响作用。     

唐山矿西南区构造复杂程度的熵函数评价

唐山矿隶属于开平煤田,位于开平向斜的北西翼,构造极为复杂。本文应用熵函数定量的对唐山矿西南区9号煤层的构造复杂程度进行了评价,所得的熵值越大,构造越简单;熵值越小,构造越复杂。评价结果与分形分维对比表明:由于对不同类型的断层分别统计和计算,以及添加了褶曲这一重要构造类型,熵函数评价结果更加科学,即西南区9号煤层的西部、北部和东部边界为构造复杂区,而在岭子背斜两侧构造则比较简单。      

开滦矿区唐山矿构造特征及成因演化

开滦矿区唐山矿位于开平向斜北西翼,隶属燕山南麓赋煤构造带,由北向南依次发育F_I、F_II、F_III、F_IV、F_V主断层,地质构造复杂,控制了井田构造格局。基于钻孔和矿井地质资料,以构造规律解析为基础,结合平衡剖面技术,探讨了唐山矿现今构造特征及构造演化期次。研究结果显示:唐山矿主体构造形成于燕山期NW-SE向的挤压应力作用,动力来源为库拉-太平洋板块与欧亚大陆的相互挤压作用;喜马拉雅期,由于库拉-太平洋板块淹没于欧亚大陆之下,唐山矿受到NW-SE向的拉张应力作用,形成了一系列小型正断层,并导致F_I逆断层发生构造反转而变为正断层;利用平衡剖面技术恢复了唐山矿构造演化过程,得到唐山矿地层缩短率为27.3%。      

Variations of monsoonal precipitation over the last 16,000 years in the eastern Nanling Mountains,South China

A 350-cm-long sediment core was recovered from Dahu Swamp in the eastern Nanling Mountains in south China for paleoclimatic investigation. Twelve ¹⁴C dates determined on organic-rich bulk samples establish a chronological sequence for this core and yield a bottom age of ~16,000 cal years BP. Multiproxies including dry bulk density, magnetic susceptibility, organic carbon isotope, median grain size, silt-size fraction and total organic matter content were used to study variations of precipitation in relation to the East Asian monsoon. The core sediments are characterized by shifts between the lacustrine sediments and marshy sediments, implying hydrological variations between expansion and shrinkage of the water body in the swamp, and suggesting relatively wetter and drier conditions, respectively. Two relatively wetter episodes lasting from ~15,000 to 14,000 cal years BP and from ~13,500 to 12,800 cal years BP were revealed, possibly corresponding to the Bølling and the Allerød warming events, and three relatively drier phases occurred between ~16,000 and 15,000 cal years BP, between ~14,000 and 13,500 cal years BP and between ~12,800 and 11,500 cal years BP. The three events synchronize with the Oldest Dryas, the Older Dryas and the Younger Dryas cooling events, respectively. A distinctly humid period lasted from ~10,000 to 6,000 cal years BP in the early- and mid- Holocene was interpreted as the Holocene Optimum period. Several short dry events were revealed, including the most pronounced one at ~8,100 cal years BP that coincides with the “8,200 year” cooling event. Multiproxies indicate an evidently dry climate prevailing in the mid-Holocene (from ~6,000 to 3,000 cal years BP), reflecting a weakening of the East Asian summer monsoon. The general trend of Holocene climate shows agreement with the 25°N summer solar insolation, suggesting that the orbitally induced insolation have played a key role in the Holocene climate in south China.     

辽宁省国土资源沙盘模型制作及特点

本文以辽宁省国土资源沙盘模型为例,详细介绍了现代沙盘模型的制作方法及特点。