南沙群岛景观及区域古地理

本文论述了南沙群岛的海底地形、海底表层沉积、珊瑚礁景观、区域新生代古地理、以永暑礁为代表的古气候与古海面，以及本区古海洋等自然地理特征。     

An interpolation method taking into account inequality constraints: II. Practical approach

Common features of models for interpolation, consistent with a finite number of inequality constraints on the range of values of a variablez, are discussed. A method based on constrained quadratic minimization yielding kriging estimates when no constraints exist, is presented. A computationally efficient formulation of quadratic minimization is obtained by using results on duality in quadratic programming. Relevant properties of the optimal interpolator are derived in a simple, self-contained way. The method is applied to mapping of horizon depth and estimation of thickness of an oil-bearing formation.     

A Simplified Basin Model For Simulating Runoff: The Struma River GIS

A GIS‐based distributed‐parameter runoff simulation model for the Struma River Basin in southwestern Bulgaria calculates the monthly snow/rain proportion, direct or surface runoff, snow cover and snowmelt, soil moisture, evapotranspiration, and total runoff. Simulation during the Bulgarian hydrologic year from November to October was compared with observed runoff data. The model closely replicates mean monthly runoff from climate conditions during the years 1961 –1990 as well as specific years. The simplified GIS model simulates hydrologic processes under limited data availability.     

南沙群岛区域地质地貌与古海洋

本文论述了南沙群岛海底地形、海底沉积物、区域地质、珊瑚礁地质地貌和区域古海洋。     

An interpolation method taking into account inequality constraints: I. Methodology

Several kinds of data can provide information about a variable measured on a one- or two-dimensional space; at some points, the value is known to be equal to a certain number. At other points, the only information may be that the variable is greater or smaller than a given value. The theory of splines provides interpolating functions that can take into account both equality and inequality data. These interpolating functions are presented. The parallel between splines and kriging is reviewed, using the formalism of dual kriging. Coefficients of dual kriging can be obtained directly by minimizing a quadratic form. By adding some inequality constraints to this minimization, an interpolating function may be calculated which takes into account inequality data and is more general than a spline. The method is illustrated by some simple one-dimensional examples.Work performed at Sohio Petroleum Company     

Water resource impacts of climate change in southwestern Bulgaria

This study assesses the regional impact of climate change on runoff in a mountainous region of southwestern Bulgaria. A GIS-based distributed hydrologic model and two climate change scenarios – HadCM2 and CCC – were employed for years around 2025 and 2085. Results from both scenarios demonstrate the basin's sensitivity of runoff to climate change, which produce significant spatial and temporal changes in the basin's water yield with maximum runoff shift into early spring and further decreases in summer runoff. There could be no reduction in mean annual runoff, except under the Hadley scenario by 2085. Changes in the magnitude of mean monthly and peak flow are associated with early snowmelt and a reduction in snow cover in spring. Increases in spatial variability of runoff reflect the basin's complex physiographic characteristics. The increase of spatial and temporal variability in runoff points to different strategies for future water resource management. This revised version was published online in July 2006 with corrections to the Cover Date.     

Division of Matrix- and Fracture-Type Shale Oils in the Jiyang Depression and Their Differences

This study discussed the division of matrix- and fracture-type shale oils in the Jiyang Depression, and proposed the concept of fracture development coefficient. The fracture development coefficient is defined as the ratio of fault throw to the distance between a shale oil well and the nearest fault. Based on CO2 content, state of water, oil production and logging response of shale oil formations, the classification of shale oils was established, i.e., a fracture-type shale oil well has a fracture development coefficient greater than 0.2, while a matrix-type one has a fracture development coefficient less than 0.2. Furthermore, the key control factors of matrix- and fracture-type shale oil enrichment were analyzed using typical anatomical and statistical methods. For matrix-type shale oil enrichment, these factors are lithofacies, total organic carbon (TOC), shale porosity and abnormal pressure; for fracture-type shale oil enrichment, they are lithofacies, extent of fracture development, and abnormal pressure. This study also first described the differences between matrix- and fracture-type shale oils. The results provide reference for the exploration of terrestrial faulted basins in eastern China.     

Sudy on Shale Cracks in Jiyang Depression

<正>1 Introduction In early oil and gas exploration in jiyang depression stage,abnormal gas logging and oil and gas shows are frequently seen in the period of the shale.Most wells obtain commercial oil flow,such as Well Luo42,xinyishen9 in zhanhua sag and Well he88 in dongying sag,shows great potential for exploration of fractured shale oil.Once upon a time people in view of the current situation in the research     

Empirical likelihood estimation of the spatial quantile regression

The spatial quantile regression model is a useful and flexible model for analysis of empirical problems with spatial dimension. This paper introduces an alternative estimator for this model. The properties of the proposed estimator are discussed in a comparative perspective with regard to the other available estimators. Simulation evidence on the small sample properties of the proposed estimator is provided. The proposed estimator is feasible and preferable when the model contains multiple spatial weighting matrices. Furthermore, a version of the proposed estimator based on the exponentially tilted empirical likelihood could be beneficial if model misspecification is suspect.     

Further research on chlorite rims in sandstones: evidence from the Triassic Yanchang Formation in the Ordos basin,China

Chlorite rims are the most common type of authigenic chlorite in sandstones, and attract particular attention because they are always found in high-quality sandstone reservoirs. This study researches chlorite rims in sandstones of the Chang 9 oil-bearing member of the Triassic Yanchang Formation in the Ordos basin, China. Using casting thin sections, a scanning electron microscope and porosity–permeability data, the following issues were addressed: (1) the formation stage of chlorite rims, (2) the relationship of chlorite rim formation to other diagenetic features, and (3) the relationship of chlorite rims with sandstone reservoir quality. From the results, the following conclusions can be drawn: (1) chlorite rims form during the A–B phase of eodiagenesis, (2) chlorite rims cannot enhance the mechanical strength of rocks and their ability to resist compaction, (3) the reason that chlorite rims inhibit quartz secondary enlargement is a change in pH and silica concentration leading to the cessation of quartz growth. However, chlorite rims have no relationship with the formation of later idiomorphic authigenic quartz; (4) chlorite rims cannot enhance the reservoir quality of sandstone, but can be an indicator of high primary intergranular porosity.