钻井岩心古水流方向确定方法和原理

为了实现钻井岩心信息最大化的应用.首先利用古地磁技术对钻井岩心进行原始方位恢复,然后通过测定岩心上具有古水流指向性的沉积构造的参数,或者通过测定岩心磁性组构判定古流向,最后经过岩心校正得出研究区的古水流方向.文中以钻井岩心上的斜层理为例,推导出其在岩心坐标系中的倾向和倾角的表达式,经过公式校正得到真倾向和真倾角的表达式,确定古流向.最终将井位、岩心恢复及古水流计算结果综合反映,获得每个井位的古水流方向,进而通过连片处理分析,可获得某区块的局部及整体的古水流趋势方向,预测砂体的展布方位.本文为钻井岩心古水流方向的确定提供了研究方法,实现了岩心信息最大化利用,可以指导油田的进一步勘探开发.     

干涉SAR中地球形状与去平地效应的关系

从分析合成孔径雷达干涉处理过程中的水平地形效应入手，通过分析地形差异所导致的相位变化，得出了对于不同轨道参数的卫星去水平地形效应时地球形状的影响是不同的结论。并从理论上证明对于ERS-1和2卫星数据可以不必考虑地球形状，即可以默认大地是水平的。     

Long-term variations in the second sectorial Stokes harmonics on the basis of TOPEX/POSEIDON altimetry between 1993 and 2000

The long-term variations in the second degree sectorial Stokes parameters of the geopotential have been determined from TOPEX-POSEIDON (T/P) satellite altimeter data, covering the period of January 1, 1993 to January 3, 2001 (T/P cycles 11-305). It is the first attempt to determine the variations in the second sectorial harmonics in the Earth’s inertia tensor due to the ocean dynamics. The variations amount to about 1 × 10⁻¹⁰ (J ₂ ⁽²⁾ ≈ 1.6 × 10⁻⁶ and S ₂ ⁽²⁾ ≈ −0.9 × 10⁻⁶). The variations are about 5% of the tidal effect. This corresponds to variations in the directions of the equatorial axes of the Earth’s inertia ellipsoid of up to 10 arc-seconds. Consequently, the annual and semi-annual variations of the Earth’s equatorial flattening is about 10⁻⁹; i.e. it corresponds to a change of 8 units of its denominator of 91 030. (The equatorial flattening ≈ 1/91 030). Since the coverage of the Earth’s ocean surface is not worldwide, and the inclination of T/P is i = 66°, it is only 58.2% (min. depth of the ocean 2 000 m) of the Earth’s surface which is processed, the torque, resulting from the seasonal transfer of masses within a sea surface layer, is not zero. It amounts up to 10¹⁶ kg m²s⁻², which is comparable to the total indirect tidal torque due to the Moon and the Sun, ∼ 3.9 × 10¹⁶ kg m²s⁻². However, the above estimate strongly depends on the adopted thickness of the sea surface layer, ΔR = 50 m. For a larger thickness of ΔR = 100 m, the seasonal torque amounts to about ∼ 2.3 × 10¹⁶ kg m²s⁻².     

Paleomagnetism of the Siberian traps: New data and a new overall 250 Ma pole for Siberia

The flood basalt province in Siberia is one of the largest in the world but the number of reliable paleomagnetic data on these volcanics is still limited. We studied lava flows and trap-related intrusions from two areas in the north and west of the Siberian platform. A dual-polarity characteristic component was isolated from most samples with the aid of stepwise thermal and alternating field demagnetization. We then compiled all published paleomagnetic data on the Siberian traps that have been obtained according to modern standards; also included are presumably trap-related overprint directions in Paleozoic rocks. Although these overprints and trap results may locally differ, the corresponding mean poles based on remagnetized sediments and volcanics show excellent overall agreement and justify pooling of both data types. Several ways of data grouping were attempted; the trap mean pole proved to be rather insensitive to statistical treatment. Irrespective of the averaging procedure used, the overall mean poles for the Siberian traps (NSP2: 55.1°N, 147.0°E; N = 8, K = 123, A₉₅ = 5.0° or NSP4: 57.2°N, 151.1°E; N = 8, K = 192, A₉₅ = 4.0°) differ slightly, but significantly from the coeval mean poles of Baltica [Torsvik, 2001; Van der Voo, R., and Torsvik, T.H., The quality of the European Permo-Triassic paleopoles and its impact on Pangea reconstructions, in: Timescales of the Paleomagnetic Field, J. E. T. Channell, D.V. Kent, W. Lowrie, and J.G. Meert, eds., AGU Geophys. Monogr., 2004, 135, 29–42]. We consider possible causes for this difference and conclude that it could be explained either by persistent non-dipole terms in the Permo-Triassic geomagnetic field or widespread inclination shallowing in the European data.     

关于章动序列计算中的地球动力学扁率的取值

刚体地球章动序列和非刚体地球章动的转换函数都和地球动力学扁率有关。ＩＡＵ１９８０章动理论中采用了一个不一致的地球动力学扁率值,从而影响了章动振幅的计算。本文介绍了章动序列计算中地球动力学扁率的取值。由地球模型１０６６Ａ或ＰＲＥＭ得到的地球动力学扁率值比由岁差观测得到的约小１％,并且不可靠。当考虑体静力学平衡被破坏时新的地球物理模型,可得到与岁差常数相一致的地球动力学扁率值。地球动力学扁率值Ｈ＝０．     

基于约束插值算法的井资料外推

Based on a detailed analysis of differences between seismic data and well logs, we discuss the problem of matching seismic traces and well logs and present a new matching method based on event search in instantaneous phase which greatly improves seismic resolution. The method is based on flattening events in instantaneous phase to compare the seismic traces to the well log traces with the same phase. We calculate the coefficients using the singular value decomposition method to extrapolate the well logs. As a result, the events in the seismic profile are continuous and match well with well logs. We apply this method to the Mao-2 well in Daqing Oilfield with good results.     

On the precession constant: Values and constraints on the dynamical ellipticity; link with Oppolzer terms and tilt-over-mode

The luni-solar precession, derived by theoretical considerations from the precession of the equator, is one of the most important parameters for computing not only precession but also nutations, due to its relation to the dynamical flattening. In this paper, we review the numerical values of this parameter, from the geodynamical point of view as well as the astronomical point of view, from the observational point of view as well as from the theoretical point of view. In particular, we point out a difference of about 1 percent between the global Earth dynamical flattening derived from the astronomical observations and the values derived from the different geophysical computations. The nutation amplitudes depend on the Earth dynamical flattening and this dependence is amplified by a resonance at an important normal mode, the Tilt-Over-Mode (TOM). Since the astronomical point of view as well as the geophysical one are confronted, we also take the opportunity to make the link between the TOM and the expressions of the nutations of the different axes which, in turn, are related with one another by the Oppolzer terms. Both, the Oppolzer terms and the TOM originate from a reference frame tilt effect. In writing the link between the nutational motions of the different axes, and so, in writing the Oppolzer terms, we also make the link with the precessional motion.     

焉耆盆地博湖坳陷侏罗纪盆地原型与成因机制

焉耆盆地博湖坳陷侏罗纪盆地原型存在诸多争论.在参考前人研究基础上,利用地震资料采用层拉平和平衡剖面技术对焉耆侏罗纪原型盆地进行恢复.研究结果表明,盆地在该时期为类前陆盆地.侏罗纪沉积期,博湖坳陷原型盆地主控因素是EW向、NE向和NW向构造.在NS向直压应力作用下,博湖坳陷中间地块向北推移,西部和东部地块分别向西南和东南运移,形成宝浪走滑断裂带、四十里城走滑断裂带和种马场隆起带,控制着坳陷沉积.     

福建省长乐—南澳断裂带,平潭—东山褶皱带基本特征的研究

闽东南沿海变质带实际上是由平潭—东山褶皱带和长乐—南澳断裂带所组成,前者是复杂的基底褶皱带,后者是大型的脆-韧性剪切带,它大体上是前者的西界。褶皱带的褶皱样式反映岩石在变质与变形时处于强塑性压扁及流变的机制。微观构造研究进一步获得变质构造岩在固态流变中的运动学和动力学特征。区域变质作用的温度为540—600℃,压力2400—3600Mpa。变质作用的高峰期约距今170Ma。