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71.
Zhanhong LIU Sitian LI Renchen XIN Changgui XU Jianchun CHENG 《Frontiers of Earth Science》2008,2(1):73-82
Bohaiwan basin, covering an area of 200 000 km2, is one of the most important oil-bearing basins in Eastern China. Rifting processes formed the basin, and two evolution
phases can be recognized. The rifting phase developed in Paleogene, and post-rifting phase occurred in Neogene. More than
200 oil fields have been found in the onshore and offshore area in Bohaiwan basin in recent years. The distribution of the
oil fields is closely related to the rich hydrocarbon depressions, and the Huanghekou depression is one of these rich hydrocarbon
depressions. A number of large and medium-sized oil and gas fields have been found in this area, such as BZ25-1, BZ34 etc.,
and the hydrocarbon was mainly from the Huanghekou depression. The formation of rich hydrocarbon source rocks depended on
the tectonic setting of rapid subsidence, favorable paleoclimatic conditions and paleolimnology environments. The effects
of paleoclimatic condition on hydrocarbon source rocks are the focus of this paper.
__________
Translated from Geological Bulletin of China, 2007, 26(7): 830–840 [译自: 地质通报] 相似文献
72.
首先介绍了地理信息系统(GIS)网络分析的发展概况;其次在已有GIS最佳遍历分析存在问题的基础上,提出了一种最佳多路遍历分析算法。并在ArcEngine环境下,以某县交通网为例,利用C#.net及ArcEngine二次开发类库实现了其最佳多路灾情巡视路线分析。算法适用范围广,可以推广到很多同类的地理网络问题。 相似文献
73.
临港新城地质特征及其对新城规划与建设的影响分析 总被引:2,自引:1,他引:1
结合临港新城三维地质调查所取得的成果,分析了该城区地质特征及对新城建设的影响,为新城规划建设提供科学依据和服务。 相似文献
74.
Yongshun John Chen 《Pure and Applied Geophysics》1996,146(3-4):621-648
The global mid-ocean ridge system is one of the most active plate boundaries on the earth and understanding the dynamic processes at this plate boundary is one of the most important problems in geodynamics. In this paper I present recent results of several aspects of mid-ocean ridge studies concerning the dynamics of oceanic lithosphere at these diverging plate boundaries. I show that the observed rift valley to no-rift valley transition (globally due to the increase of spreading rate or locally due to the crustal thickness variations and/or thermal anomalies) can be explained by the strong temperature dependence of the power law rheology of the oceanic lithosphere, and most importantly, by the difference in the rheological behavior of the oceanic crust from the underlying mantle. The effect of this weaker lower crust on ridge dynamics is mainly influenced by spreading rate and crustal thickness variations. The accumulated strain pattern from a recently developed lens model, based on recent seismic observations, was proposed as an appealing mechanism for the observed gabbro layering sequence in the Oman Ophiolite. It is now known that the mid-ocean ridges at all spreading rates are offset into individual spreading segments by both transform and nontransform discontinuities. The tectonics of ridge segmentation are also spreading-rate dependent: the slow-spreading Mid-Atlantic Ridge is characterized by distinct bulls-eye shaped gravity lows, suggesting large along-axis variations in melt production and crustal thickness, whereas the fast-spreading East-Pacific Rise is associated with much smaller along-axis variations. These spreading-rate dependent changes have been attributed to a fundamental differences in ridge segmentation mechanisms and mantle upwelling at mid-ocean ridges: the mantle upwelling may be intrinsically plume-like (3-D) beneath a slow-spreading ridge but more sheet-like (2-D) beneath a fast-spreading ridge. 相似文献
75.
浙闽山区茶叶生产基地评价的探讨 总被引:6,自引:0,他引:6
茶叶基地的评价包括对基地的自然和经济条件的评估,应用系统分析方法,将自然和经济条件进行定量的综合评估,用综合评价值区分基地间的差异,最后定性与定量相结合,提出茶叶生产基地的合理布局. 相似文献
76.
The scope of the present paper is to provide analytic solutions to the problem of the attitude evolution of a symmetric gyrostat about a fixed point in a central Newtonian force field when the potential function isV
(2).We assume that the center of mass and the gyrostatic moment are on the axis of symmetry and that the initial conditions are the following: (t
0)=0, (t
0)=0, (t
0)=(t
0)=0, 1(t
0)=0, 2(t
0)=0 and 3(t
0)=
3
0
.The problem is integrated when the third component of the total angular momentum is different from zero (B
1 0). There now appear equilibrium solutions that did not exist in the caseB
1=0, which can be determined in function of the value ofl
3
r
(the third component of the gyrostatic momentum).The possible types of solutions (elliptic, trigonometric, stationary) depend upon the nature of the roots of the functiong(u). The solutions for Euler angles are given in terms of functions of the timet. If we cancel the third component of the gyrostatic momentum (l
3
r
=0), the obtained solutions are valid for rigid bodies. 相似文献
77.
近年来,作者发展了七种以上重要找矿指示元素的野外快速分析法,此乃其一。文中提出一种新的金样冷浸技术,引进了新的光导光度检测方法,样品经溴化钠—硫酸—过氧化氢冷浸,用经丙酮—MIBK处理的泡沫塑料富集金,经混合解脱剂解脱并直接取解脱液用改进的微珠析出法或用光导光度法测定。取10g样品,可测定0.0005-50g/t范围内的金。方法简便、快速,可在普查分队驻地进行,每一工作日可测定80多个样品,由于废弃了王水分解样品和泡沫塑料的灰化,具有广阔的应用前景。 相似文献
78.
Jin-Yong Lee Jeong-Yong Cheon Hyung-Pyo Kwon Hee-Sung Yoon Seong-Sun Lee Jong-Ho Kim Joung-Ku Park Chang-Gyun Kim 《Environmental Geology》2006,51(4):581-593
Attenuation characteristics of landfill leachate were examined for two uncontrolled landfills in Korea. The two landfills containing municipal wastes without appropriate bottom liner and leachate treatment system have different landfill age, waste volume, and most importantly different hydrogeologic settings. One landfill (Cheonan landfill) is situated in an open flat area while the other (Wonju landfill) is located in a valley. Variations of various parameters including dissolved organic carbon (DOC), dissolved oxygen (DO), alkalinity, pH, electrical conductivity (EC), redox potential (ORP), ammonia (NH3), nitrate (NO3−), sulfate (SO42−), and chloride (Cl−) were examined along groundwater flow path. All these parameters were analyzed every month for a year. In the interior of the landfills, typical anaerobic conditions revealed by low DO and NO3 concentrations, negative ORP values, high NH3, alkalinity, and Cl− concentrations were observed. Generally, higher levels of contaminants (DOC, NH3, and Cl−) were detected in the dry season while they were greatly lowered in the wet season. Significantly, large decrease of Cl- concentration in the wet season indicates that the dilution or mixing is one of dominant attenuation mechanisms of leachate. But detailed variation behaviors in the two landfills are different and they were largely dependent on permeability of surface and subsurface layers. The intermediately permeable surface of the landfills receives part of direct rainfall infiltration but most rainwater is lost to fast runoff. The practically impermeable surface of clayey silt (paddy field) at immediately adjacent to the Cheonan landfill boundary prevented direct rainwater infiltration and hence redox condition of the ground waters were largely affected by that of the upper landfill and the less permeable materials beneath the paddy fields prohibited dispersion of the landfill leachate into down gradient area. In the Wonju landfill, there are three different permeability divisions, the landfill region, the sandy open field and the paddy field. Roles of the landfill and paddy regions are very similar to those at the Cheonan. The very permeable sandy field receiving a large amount of rainwater infiltration plays a key role in controlling redox condition of the down gradient area and contaminant migration. This paper reports details of the attenuation and redox conditions of the landfill leachates at the two uncontrolled landfills. 相似文献
79.
LI Zheng-xi 《吉林大学学报(地球科学版)》2006,(Z2)
对低阻油气储层的测井响应特征和储层物性特征进行了研究,并针对研究区域低阻储层的特点,以岩心与测井数据的相关性为依据,提出了适合地区特点的储层参数解释方法。通过应用三水导电模型,提高了低阻储层的测井解释精度。 相似文献
80.
在野外调查和收集现有资料基础上,对下河泉水源地水文地质条件、泉水流量动态、水源地保证程度与可能的环境问题进行了分析,论证了建立下河泉水源地的可行性. 相似文献