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101.
XU Huiand DUAN Wansuo State Laboratory of Numerical Modeling for Atmospheric Sciences Geophysical Fluid Dynamics 《大气科学进展》2008,(4)
With the Zebiak-Cane(ZC)model,the initial error that has the largest effect on ENSO prediction is explored by conditional nonlinear optimal perturbation(CNOP).The results demonstrate that CNOP-type errors cause the largest prediction error of ENSO in the ZC model.By analyzing the behavior of CNOP- type errors,we find that for the normal states and the relatively weak El Nino events in the ZC model,the predictions tend to yield false alarms due to the uncertainties caused by CNOP.For the relatively strong El Nino events,the ZC model largely underestimates their intensities.Also,our results suggest that the error growth of El Nino in the ZC model depends on the phases of both the annual cycle and ENSO.The condition during northern spring and summer is most favorable for the error growth.The ENSO prediction bestriding these two seasons may be the most diffcult.A linear singular vector(LSV)approach is also used to estimate the error growth of ENSO,but it underestimates the prediction uncertainties of ENSO in the ZC model.This result indicates that the different initial errors cause different amplitudes of prediction errors though they have same magnitudes.CNOP yields the severest prediction uncertainty.That is to say,the prediction skill of ENSO is closely related to the types of initial error.This finding illustrates a theoretical basis of data assimilation.It is expected that a data assimilation method can filter the initial errors related to CNOP and improve the ENSO forecast skill. 相似文献
102.
百色盆地东部田东坳陷那坤地区古近系那读组三段下部发育一套数米至数十米厚的湖相灰岩,岩石以浅灰色-灰色、含大量的螺蚌化石和具核形石结构为特征,间夹有薄层的泥岩、钙质泥质粉砂岩。本文在实测地表剖面和详细观察岩心的基础上,仔细研究了此套灰岩的岩石学特征。依据丰富的原生沉积构造、古生物化石标志以及沉积地球化学、测井相特征将湖相灰岩的沉积相划分为滨湖、颗粒滩、浅湖三个亚相以及灰泥坪、沼泽、颗粒坪、滩缘、滩核、滩间水道、灰泥浅湖、泥质浅湖等八个微相,并详细地研究了各微相的沉积特征。结合该灰岩的区域分布和沉积相的平面展布格局指出沉积相主体属于浅湖的颗粒滩,并提出了相应的沉积相模式。 相似文献
103.
LEI Huaiyan LIU Zhihong XU Maoquan GUAN Baocong Institute of Oceanography Environment Xiamen University Xiamen Fujian State Key Laboratory of Gas Geochemistry Institute of Geology Chinese Academy of Sciences Lanzhou Gansu 《《地质学报》英文版》2004,78(3):701-714
There are few 3-D seismic profiles and drillings in the middle part of the Qibei depression in the Dagang oilfield, and more than 70% of the 2-D seismic profiles were completed before the 1980s. Meanwhile, changes in the terrestrial formations in this region have been large and complex. These factors have made it difficult to predict reservoirs in this area. The purpose of this paper is to establish a methodology for predicting potential gas and oil reservoirs. Our research combines sequence stratigraphy, well-logs, and seismic analysis to elucidate the prediction of flagstone reservoirs in the S1 (Sha-I) Member in the middle of the Qibei depression. Previous research indicates that these rocks were deposited in an environment that had a semiarid, northern subtropical, and warm, humid climate. The objective strata currently consist mainly of lake fades, deeper lake facies, and shore-shallow lake facies. The study reveals that the lower section of the S1 Member is an important objective region for explora 相似文献
104.
Mangshan Loess in Central China and the Paleomonsoon Variationssince the Last Interglaciation 总被引:1,自引:0,他引:1
JIANG Fuchu WANG Shubing ZHAO Zhizhong FU Jianli Institute of Geomechanics Chinese Academy of Geological Sciences Beijing State Key Laboratory of Loess Quaternary Geology Chinese Academy of Sciences Xi''an Shaanxi 《《地质学报》英文版》2004,78(3):813-819
The Mangshan Yuan is a loess platform on the southern bank of the Yellow River, which is located in northwestern Zhengzhou of Henan Province, China. The typical Zhaoxiayu section of the Mangshan Yuan preserves stratigraphical loess units above S10 with a total thickness of 172.1 m, which includes 15.7 m of the last interglacial paleosol S1, 77.3 m of the last glacial loess L1 that consist of 41.6 m of the late stade L1LL1, 13.2 m of the interstade L1SS1 and 22.5 m of the early stade L1LL2. Based on the age marking points by correlating magnetic susceptibility of the section with the SPECMAP curve, the timescale of the section was constructed, and the average accumulation rate and the resolution of each loess strata over the S2 were subsequently calculated using the 相似文献
105.
贝塞尔曲线在虚拟森林景观单树几何模型构建中的应用 总被引:10,自引:0,他引:10
虚拟景观模型的生成,需要对实际景观进行抽象和简化。树几何模型和数字高程模型(DEM)是构成虚拟森林景观的两大要素。而树几何模型的构建又是林业GIS三维可视化的基础。在树几何建模中,树干及树枝形状的可视化表达具有突出意义。由于实际树种的复杂性,在计算机中建树模型,通常采用基于过程建模的方式,而这将面临用户如何对模型进行交互式控制的问题:参数太少,不足以描述树形态特征,而参数太多,则模型难以生成和理解。为了解决这个问题,我们引进贝塞尔(Bezier)曲线这种基于控制点的自由曲线来描述树木中的树干以及树枝形状,利用对曲线控制点的变动来控制曲线的形状,进而生成形态各异的树形状,对此,我们基于ActiveX技术生成Bezier曲线控件。结果表明,该方法能够表示多种形状的树干与树枝,具有操作简捷、计算速度快,可视化效果良好的优点。 相似文献
106.
世界内生磷矿地质及成矿规律 总被引:1,自引:1,他引:0
内生磷灰石型矿床在世界磷矿工业中的地位不断上升。世界内生磷矿可划分为超基性-碱性-碳酸岩类(占内生磷矿储量的90%以上,又分超基性-碱性-碳酸岩型、碱性-碳酸岩型、超基性-碱性岩型、超基性-碳酸岩型、碳酸岩型、碱性岩型六亚类),基性岩与超基性岩类,其它类等三大类。各类矿床主要岩石类型,矿物组合,岩体形态、产状、结构,矿体与矿石及其主要产地、大地构造位置等都各具特色。以成矿理论与成矿规律为指导,通过地、物、化、遥综合手段找矿将取得事半功倍的效果。 相似文献
107.
Massive Sulphide Deposits Related to the Volcano-Passive Continental Margin in the Altay Region 总被引:3,自引:0,他引:3
WANG Jingbin DENG Jiniu ZHANG Jinhong QIN KezhangBeijing Institute of Geology for Mineral Resources State Bureauof Nonferrous Metal Industry Andingmenwai Beijing Zhu Xiling 《《地质学报》英文版》1999,73(3):253-263
The Devonian volcano-passive continental margin in southern Altay is a significant volcanogenic massive sulphide metallogenic belt. Acidic volcanism has been dominant on the inner side of the volcano-passive continental margin, i.e., near the old land, resulting in a Pb-Zn metallogenic sub-belt, in which the ore deposits are hosted by sedimentary rocks in volcanic series, as represented by the large Koktal Pb-Zn deposits. In the central part of the margin far away from the old land, bimodal volcanic formations are well developed, forming volcanics-hosted Cu-Zn metallogenic sub-belts, e.g., the large-scale Ashele Cu-Zn deposit. The Qiaoxiahala sub-belt on the outer side of the margin near the ocean ridge is located at the spreading central trough, where ophiolite suites are developed. This type of deposits is rich in gold and copper, similar to the Cyprus-type Fe-Cu-Au metallogenic sub-belt in metallogenic environment (represented by the Qiaoxiahala medium-scale Fe-Cu-Au deposit). From the old land to th 相似文献
108.
本文针对遥感信息的数据特征探讨了卫星遥感信息处理与多元统计算法之间的关系,并从实际出发对最小二乘残差技术,目标模式识别,增强主成份分析等方法的应用作了介绍。 相似文献
109.
Arps递减开发模型 总被引:22,自引:8,他引:14
本文在Arps递减产能预测模型的基础上提出了Arps递减开发模型,提出了开发速度,采出程度等开发指标的数学关系式,分析了参数Arps递减开发模型的影响,提出了开发初期Arps递减开发模型的确定方法,便于开发初期决策,制作了Arps递减开发模型的logVd-logRp图版,logVd-log(Dt)图版,logRp-log(Dt)图版,提出了开发中晚期Arps递减开发模型的判断方法,三点抛物线法和三 相似文献
110.