燕辽地区晚中生代动物君及其古生态和古地理意义

燕辽地区的中侏罗-早白垩世地层中共有3个动物群贯穿始终，即燕辽动物群、热河动物群、阜新动物群，分别分布于中侏罗世、晚侏罗世及早白垩世，构成多门类化石群的组合序列.根据以昆虫为主的动物群组合序列研究，可以推测中侏罗世燕辽地区处于温带气候条件下，森林沼泽发育，分布广，但水面规模不大，水体不深，地形起伏差异较小，而晚侏罗世相似，陆地植被茂盛，森林极为广布.到早白垩世尼欧克姆期，动物群的种类相对较贫乏，以陆生昆虫为主，出现的昆虫大多为典型亚热带昆虫，说明该地气候仍偏热，但湖泊显著减少，已逐渐向干燥的气候过渡。从昆虫类及其他一些化石的古地理分布特征分析，可以作出如下推断，即：劳亚大陆或欧亚大陆与北美、非洲等大陆分离的最后时限不会早于中侏罗世，以后随着泛大陆解体，昆虫中一些类群（如蚊歇蛉科等）的早期代表扩散到其他大陆，最终现成现今的分布格局。在这一过程中，第三纪白令陆桥虽有一定作用，但并不是主要和唯一的途径。     

贫信息条件下的多点变形预测模型及其应用

常用的单点变形分析方法没有利用监测点间相互关系的信息，不足以反映变形体整体的变形规律。本文将单点的变形预测模型扩展为多点的变形预测模型，建立了贫信息条件下的多点预测模型。进行了实例建模与分析，结果表明，多点预测模型为解决少数据，多因子的动态系统预测与分析提供了新的途径。     

泥炭样品不同有机组分的~(14)C测年的初步研究

分别用ＮａＣｌＯ、ＮａＯＨ溶液、Ｎａ４Ｐ２Ｏ７和ＮａＯＨ混合溶液和有机溶剂对采自延庆盆地大王庄两个泥炭样品进行前处理，每个样品获得１０个不同有机组分，对这些有机组分的１４Ｃ年龄测定值进行对比。以探讨泥炭等样品不同有机组分１４Ｃ测年的可靠性     

Preliminary Study on Paleoearthquake Chronology on the Northern Liulengshan Piedmont Fault in Yangyuan, Hebei Province, China

The northern Liulengshan piedmont fault is located along the southern margin of the Yangyuan basin and represents a dip-slip normal fault,generally NEE-trending and NNW-dipping.Landforms offset by the fault are fairly developed and well preserved in the Dushanpu area of Yangyuan County,Hebei Province.Two trenches were excavated in front of a scarp of the northern Liulengshan piedmont fault at Dushanpu and two paleoseismic events were revealed in the trenches,from which several samples were collected for dating.The samples were dated using the IRSL dating technique.The preliminary result shows the possible ages of the two paleoseismic events.     

青藏—蒙古高原东缘构造过渡带的布格重力场特征及地壳上地幔结构

本文从青藏—蒙古高原东缘构造过渡带的布格重力场特征、地壳厚度和上地幔密度分布状态入手,就该带具有较统一的地球动力学背景的地球物理标志,壳-幔系统动力学模式及重力均衡调整等问题进行了讨论     

偶氮氯膦Ⅲ双波长分光光度法同时测定铀矿石中钍和铀

本文对偶氮氯膦Ⅲ与钍、铀的显色反应作了研究,提出了三烷基氧膦-G.D.X-301萃取色层分离、偶氮氯膦Ⅲ双波长分光光度法同时测定铀矿石中钍和铀的方法。方法简便,精密度、准确度良好。     

我国盐湖沉积物中的硫酸盐还原细菌及其地球化学作用(英文)

本文对我国某些盐湖和苦水湖沉积物中的硫酸盐还原细菌进行了分离和鉴定。讨论了它们所处的耐盐度、温度、pH等生态条件。从而探讨了它们对沉积物中有机质的富集和保存所起的作用。同时,由于它们在还原硫酸盐时产生大量的硫化氢,导致沉积物中的金属离子以硫化物形式大量地沉淀和富集,这对次生硫化矿沉积物的形成也起着较大的作用。     

Incremental Nonlinear Models

In this paper the incremental nonlinear models are generally discussed, the correlation of this sort of models with others and the difference between them are interpreted, and some basic concepts are clarified. We presented a nonlinear dilatant stress-strain model for soil, which is referred to as KKG model for the sake of simplicity. The experimental results of a sand sample are used to determine the moduli for the following models KKG, KG (the deformation model), and Eν (elastoplastic model) respectively. The comparison of the calculation values of these models with the associated experimental results shows good fittings and prediction of KKG model, and its good simulation of soil dilatant behaviour in particular. The predicted pore pressure and effective stress path have a reasonably good agreement with observed results as well.     

The effect of the electrical anisotropy on the response of helicopter-borne frequency-domain electromagnetic systems

Helicopter electromagnetic (HEM) systems are commonly used for conductivity mapping and the data are often interpreted using an isotropic horizontally layered earth model. However, in regions with distinct dipping stratification, it is useful to extend the model to a layered earth with general anisotropy by assigning each layer a symmetrical 3 × 3 resistivity tensor. The electromagnetic (EM) field is represented by two scalar potentials, which describe the poloidal and toroidal parts of the magnetic field. Via a 2D Fourier transform, we obtain two coupled ordinary differential equations in the vertical coordinate. To stabilize the numerical calculation, the wavenumber domain is divided into two parts associated with small and large wavenumbers. The EM field for small wavenumbers is continued from layer to layer with the continuity conditions. For large wavenumbers, the EM field behaves like a DC field and therefore cannot be sensed by airborne EM systems. Thus, the contribution from the large wavenumbers is simply ignored. The magnetic fields are calculated for the vertical coaxial (VCX), horizontal coplanar (HCP) and vertical coplanar (VCP) coil configurations for a helicopter EM system. The apparent resistivities defined from the VCX, VCP and HCP coil responses, when plotted in polar coordinates, clearly identify the principal anisotropic axes of an anisotropic earth. The field example from the Edwards Aquifer recharge area in Texas confirms that the polar plots of the apparent resistivities identify the principal anisotropic axes that coincide well with the direction of the underground structures.