基于SLR时间序列构建STRF及其与ITRF2008转换关系的研究

利用SLR时间序列与ITRF2008的公共参考站的坐标及速度信息,实现两者间的欧几里得标准相似变换,以核心参考站在1983—2008年的SLR时间序列解算了各历元与ITRF2008的转换参数,并对转换参数进行统计分析,结果可靠。     

IERS地球参考系统、大地测量常数及其实现

介绍了国际地球自转服务局（IERS，International Earth Rotation Service）所定义的地球参考系统、大地测量常数及其实现，IERS规范（2003）中一些新的内容．特别是IERS采用国际地球参考系统2000（ITRS2000）后的一些新进展。对ITRS2000的实现,即国际地球参考框架2000（ITRF2000）的定义、主要参数、及其应满足的条件进行了研究，重点指出了它和历史上各个ITRFyy的不同、特色及其联系。     

高精度引潮力计算中地球扁率的影响

计算了地球扁率对月亮和太阳引潮力影响的量级,并对其空间分布特征、频率分布特征进行了分析,以及利用ELP2000-85星历计算了月亮引潮位中地球扁率影响项的调和展开.结果表明,引潮力中地球扁率的影响最大值接近2×10-11ms-2.引潮位调和展开结果中,振幅大于4×10-13ms-2的潮波项共有16项.     

CGCS 2000与PZ-90.02坐标系的对比

根据CGCS 2000和PZ-90.02坐标系的椭球基本常数,推导和比较了CGCS 2000椭球和PZ-90.02椭球的主要几何参数和物理参数,分析了同一点在两个椭球下的大地坐标、正常重力以及正常重力垂直梯度的差异。研究表明,同一点在CGCS 2000椭球与PZ-90.02椭球下的大地坐标差值随着经纬度变化而变化,经度、纬度和高度的最大差值的绝对值分别约为0.147 743 00″、0.011 603 10″和0.772 345m;CGCS 2000椭球与PZ-90.02椭球上的正常重力值和正常重力垂直梯度的差值的绝对值分别约为3.067 18×10~(-6)m/s~2和1.461 73×10~(-3)E。     

CORS坐标参考框架更新探讨

CORS系统运行过程中,由于站点的相对沉降、搬迁、天线更换等原因,导致基准站/网坐标发生了明显变化,必须进行局部站点或站网更新。本文阐述了CORS坐标参考框架的更新原则、方法,针对广东省CORS改造升级过程基准站坐标变化情况,发现了引起基准站坐标变化的天线罩问题,并研究了“偏心观测量”的处理方案;研究解决了个别基准站坐标更新及基准站网坐标参考框架更新问题,保证了广东省CORS系统的持续、高精度运行及站网坐标参考框架的延续。     

Calculation of circulation in the South China Sea during summer of 2000 by the modified inverse method

On the basis of hydrographic data obtained in August 2000 cruise, the circulation in the South China Sea (SCS) is computed by the modified inverse method in combination with SSH data from TOPEX/ERS-2 analysis. For study of the dynamical mechanism, which causes the pattern of summer circulation in the SCS, the diagnostic model (Yuan et al. 1982. Acta Oceanologica Sinica,4(1):1-11; Yuan and Su. 1992. Numerical Computation of Physical Oceanography.474-542) is used to simulate numerically the summer circulation in the SCS. The following results     

华南花岗岩数据库--一个在Microsoft Access中编写的实用小数据库

在Microsoft Access 2000中编辑制作的华南花岗岩数据库,由24张表格和相应的表单、部分查询组成,可以方便地实现花岗岩数据的管理和GeoKit、Mapgis等软件对数据的引用处理;界面友好,操作简单,是花岗岩类数据收录、管理与综合分析的有用工具.     

Comparison of Methods Used to Estimate Conventional Undiscovered Petroleum Resources: World Examples

Various methods for assessing undiscovered oil, natural gas, and natural gas liquid resources were compared in support of the USGS World Petroleum Assessment 2000. Discovery process, linear fractal, parabolic fractal, engineering estimates, PETRIMES, Delphi, and the USGS 2000 methods were compared. Three comparisons of these methods were made in: (1) the Neuquen Basin province, Argentina (different assessors, same input data); (2) provinces in North Africa, Oman, and Yemen (same assessors, different methods); and (3) the Arabian Peninsula, Arabian (Persian) Gulf, and North Sea (different assessors, different methods). A fourth comparison (same assessors, same assessment methods but different geologic models), between results from structural and stratigraphic assessment units in the North Sea used only the USGS 2000 method, and hence compared the type of assessment unit rather than the method. In comparing methods, differences arise from inherent differences in assumptions regarding: (1) the underlying distribution of the parent field population (all fields, discovered and undiscovered), (2) the population of fields being estimated; that is, the entire parent distribution or the undiscovered resource distribution, (3) inclusion or exclusion of large outlier fields; (4) inclusion or exclusion of field (reserve) growth, (5) deterministic or probabilistic models, (6) data requirements, and (7) scale and time frame of the assessment. Discovery process, Delphi subjective consensus, and the USGS 2000 method yield comparable results because similar procedures are employed. In mature areas such as the Neuquen Basin province in Argentina, the linear and parabolic fractal and engineering methods were conservative compared to the other five methods and relative to new reserve additions there since 1995. The PETRIMES method gave the most optimistic estimates in the Neuquen Basin. In less mature areas, the linear fractal method yielded larger estimates relative to other methods. A geologically based model, such as one using the total petroleum system approach, is preferred in that it combines the elements of petroleum source, reservoir, trap and seal with the tectono-stratigraphic history of basin evolution with petroleum resource potential. Care must be taken to demonstrate that homogeneous populations in terms of geology, geologic risk, exploration, and discovery processes are used in the assessment process. The USGS 2000 method (7th Approximation Model, EMC computational program) is robust; that is, it can be used in both mature and immature areas, and provides comparable results when using different geologic models (e.g. stratigraphic or structural) with differing amounts of subdivisions, assessment units, within the total petroleum system.     

United States Geological Survey's Reserve-Growth Models and Their Implementation

The USGS has developed several mathematical models to forecast reserve growth of fields both in the United States (U.S.) and the world. The models are based on historical reserve growth patterns of fields in the U.S. The patterns of past reserve growth are extrapolated to forecast future reserve growth. Changes of individual field sizes through time are extremely variable, therefore, the reserve growth models take on a statistical approach whereby volumetric changes for populations of fields are used in the models. Field age serves as a measure of the field-development effort that is applied to promote reserve growth. At the time of the USGS World Petroleum Assessment 2000, a reserve growth model for discovered fields of the world was not available. Reserve growth forecasts, therefore, were made based on a model of historical reserve growth of fields of the U.S. To test the feasibility of such an application, reserve growth forecasts were made of 186 giant oil fields of the world (excluding the U.S. and Canada). In addition, forecasts were made for these giant oil fields subdivided into those located in and outside of Organization of Petroleum Exporting Countries (OPEC). The model provided a reserve-growth forecast that closely matched the actual reserve growth that occurred from 1981 through 1996 for the 186 fields as a whole, as well as for both OPEC and non-OPEC subdivisions, despite the differences in reserves definition among the fields of the U.S. and the rest of the world.