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1.
杨占峰 《化工矿产地质》2006,28(1):57-60,64
皂土是用于葡萄酒行业的一种膨润土,其主要成分蒙脱石具有的晶格置换性能、负电性、离子交换性、水体系特性(膨胀性、悬浮性)等,使其成为葡萄酒澄清剂优质原料。通过在涿州皂土应用实践中对其性能的进一步认识,认为它仍有进一步扩展的应用及市场空间。  相似文献   
2.
鄂东南地区印支期以来构造变形特征及油气意义   总被引:8,自引:5,他引:8  
利用区域地震大剖面及MT资料,结合地面地质调查成果,对鄂东南地区的深部地质结构及典型构造样式进行了分析,认为该区发育以基底岩系顶面和志留系顶面为主滑脱面的大型逆冲推覆构造,并识别出双重逆冲构造、叠瓦状构造、台阶式结构、对冲构造及反冲断层等典型构造样式;同时对上下地质结构的变异进行了探讨,提出志留系滑脱层之下的“原地体”具有变形相对较弱、褶皱宽缓开阔的特点,在后期拉张改造中受到上盘“异地体”的保护,应是有利的油气勘探领域,双重逆冲构造内部发育的断层相关褶皱(如随阳构造)是重点勘探目标。  相似文献   
3.
遥感技术预测油气勘探靶区   总被引:1,自引:0,他引:1  
应用遥感技术预测油气勘探靶区具有低成本、高效率的特点。目前有直接和间接两种油气遥感方法用于预测油气勘探靶区。简单介绍了这两种方法的原理,重点对遥感影像中的线-环影像构造异常和烃渗漏异常所表现的特征进行了全面总结,最后对遥感技术在预测油气勘探靶区的应用前景进行了展望。  相似文献   
4.
米探1井取得天然气勘探突破表明鄂尔多斯盆地奥陶系马家沟组四段具有巨大勘探潜力,然而,对盆地奥陶纪马四期古构造格局和岩相古地理研究还存在争议,制约了下步天然气勘探进程。为此,基于地震、野外露头、钻井、岩芯、微观薄片和测井等基础资料,对马家沟组四段构造- 岩相古地理开展了系统研究,确定了盆地奥陶纪马四期古构造格局,并恢复出马家沟组四段岩相古地理,预测了有利勘探区。研究结果表明:① 鄂尔多斯盆地奥陶纪马四期发育“两陆三隆四坳”的古构造格局,其中两陆为伊盟古陆和阿拉善古陆,三隆分别为中央古隆起、中条古隆起和神木- 志丹低隆起,四坳为西南边缘坳陷、桃利庙坳陷、府谷坳陷和柳林坳陷;② 马四期为碳酸盐岩内缓坡和中缓坡沉积,其中内缓坡又发育白云岩坪、含云膏坪、微生物丘、灰泥丘、砂屑滩、丘滩间海和灰质潟湖等7类微相;③ 古构造格局控制马家沟组四段沉积分异,微生物丘、灰泥丘和砂屑滩等3类有利储集相主要沿中央古隆起和神木- 志丹低隆起等古地貌高部位分布。因此认为,神木—靖边地区是有利储层发育区,且处于岩性相变带,生储盖配置关系好,具有良好的成藏条件,是天然气勘探的有利靶向区。  相似文献   
5.
A method for sea surface wind field retrieval from SAR image mode data   总被引:2,自引:0,他引:2  
To retrieve wind field from SAR images, the development for surface wind field retrieval from SAR images based on the improvement of new inversion model is present. Geophysical Model Functions(GMFs) have been widely applied for wind field retrieval from SAR images. Among them CMOD4 has a good performance under low and moderate wind conditions. Although CMOD5 is developed recently with a more fundamental basis, it has ambiguity of wind speed and a shape gradient of normalized radar cross section under low wind speed condition. This study proposes a method of wind field retrieval from SAR image by combining CMOD5 and CMOD4 Five VV-polarisation RADARSAT2 SAR images are implemented for validation and the retrieval results by a combination method(CMOD5 and CMOD4) together with CMOD4 GMF are compared with QuikSCAT wind data. The root-mean-square error(RMSE) of wind speed is 0.75 m s-1 with correlation coefficient 0.84 using the combination method and the RMSE of wind speed is 1.01 m s-1 with correlation coefficient 0.72 using CMOD4 GMF alone for those cases. The proposed method can be applied to SAR image for avoiding the internal defect in CMOD5 under low wind speed condition.  相似文献   
6.
深水碳酸盐岩是有利的油气储集岩,中东地区上白垩统Khasib组缓坡型深水碳酸盐岩是重要的产油层系.伊拉克H油田Khasib组储层非均质性较强,储层发育特征及控制因素、油气分布规律不清,制约了选区评价及勘探部署.在区域地质调研的基础上,基于岩心、薄片和测井资料,对H油田Khasib组岩相、沉积微相和沉积模式、储层发育控制...  相似文献   
7.
This paper proposes an automatic framework for land cover classification. In majority of published work by various researchers so far, most of the methods need manually mark the label of land cover types. In the proposed framework, all the information, like land cover types and their features, is defined as prior knowledge achieved from land use maps, topographic data, texture data, vegetation’s growth cycle and field data. The land cover classification is treated as an automatically supervised learning procedure, which can be divided into automatic sample selection and fuzzy supervised classification. Once a series of features were extracted from multi-source datasets, spectral matching method is used to determine the degrees of membership of auto-selected pixels, which indicates the probability of the pixel to be distinguished as a specific land cover type. In order to make full use of this probability, a fuzzy support vector machine (SVM) classification method is used to handle samples with membership degrees. This method is applied to Landsat Thematic Mapper (TM) data of two areas located in Northern China. The automatic classification results are compared with visual interpretation. Experimental results show that the proposed method classifies the remote sensing data with a competitive and stable accuracy, and demonstrate that an objective land cover classification result is achievable by combining several advanced machine learning methods.  相似文献   
8.
在大数据时代,高分辨率对地观测技术实现了对地球表层地理现象和地理过程最为真实、量化、全面覆盖又快速更新的数据化记录,可为地理空间认知研究的新发展奠定时空信息聚合与挖掘计算的基准。地理图斑是影像空间映射到地理空间中对于地理实体的抽象化表达,是构建地理场景和承载地理空间各类信息进而开展模式挖掘的最小单元。本文以地理图斑为基本对象,通过分析其中视觉模拟、符号推测等几类机器学习的协同计算机制,从空间、时间与属性等维度构建了集“分区分层感知”、“时空协同反演”、“多粒度决策”三者于一体的地理图斑智能计算模型,并以在贵州息烽县、广西江州区开展的农业种植结构制图与规划决策为应用案例,探索了地理图斑分布、生长以及功能3种模式的挖掘方法,并进一步设计了动态视角下开展图斑动力模式挖掘的研究思路。  相似文献   
9.
格尔木辐射站是青海省唯一的太阳辐射观测一级站,地处柴达木盆地,太阳总辐射及地表反射辐射均较强.1993—2011年19 a的观测结果表明:反射辐射时总量的变化规律与总辐射时总量同步,只是量值比较小,总辐射瞬时最大值为1 596 W/m2,反射辐射瞬时最大值为383 W/m2;总辐射日总量、反射辐射日总量的年变化曲线呈不规则的正弦波曲线变化过程,两者变化趋势完全一致;总辐射日总量、反射辐射日总量的年变化、年际变化与日照时数相同,说明日照时数是太阳总辐射、反射辐射的重要影响因素之一;总辐射日总量、反射辐射日总量均是夏季>秋季>春季>冬季,反射比是冬季>春季>秋季>夏季;反射比分布主要与太阳高度角的变化有关,反射比的大小取决于地面的性质和状态,地面被积雪覆盖时,各时及日反射比值明显大于晴天和土壤潮湿的时期.  相似文献   
10.
ABSTRACT

The per capita CO2 emissions (PCCE) of many developing countries like China have been rising faster than total CO2 emissions, and display spatial divergence. Such temporal growth and spatial divergence will have a significant influence on efforts to mitigate CO2 emissions. Given the research gap on the impact of the structural transition in population on PCCE, we constructed an econometric model using the dynamic panel method. The results reveal that the population structural transition has a significant nonlinear impact on PCCE, as the rate of population growth in China decelerates. Both demographic ageing and urban-rural migration have a stronger impact on PCCE than other factors. This effect, however, decreases beyond a certain threshold. An increase in the number of households due to urbanization and family downsizing has resulted in a positive effect on PCCE, without a threshold turning point. The research also finds that an increased share of the service sector in employment can reduce PCCE only if the sector employs more than 31.56% of the total employed population. Overall, these findings indicate that policymakers should pay attention to the prominence of the demographic structural transition for effective climate policy.

Key policy insights
  • Policymakers should address rising per capita carbon emissions (PCCE) and their spatial divergence in future climate policies, not just total CO2 emissions.

  • The transitioning demographics of ageing and urbanization in China show a nonlinear, inverted U-shaped effect on PCCE instead of a continuously positive effect.

  • Based on the nonlinear effect of employment structure on PCCE, policymakers should focus on the relationship between the structural transition of the economy and PCCE in future climate mitigation policies.

  相似文献   
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