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81.
基于陆上油田密井网的河流相储层构型研究,经过数十年积累,理论基础及表征方法已比较成熟,然而,将其应用于海上油田稀疏井网条件时,依然面临较大的挑战。笔者团队经过多年探索,基于海上油田开发地质研究方法,形成了井震结合、以"复合砂体"为核心的海上河流相复合砂体构型理论与表征方法,其特点在于运用三维原型建模、地震构型相预测及地震驱动确定性建模等技术,重点表征影响海上油田开发的五、六、七级构型单元(复合河道带、单一河道带、复合点坝),针对开发阶段的小层细分对比及不连续渗流屏障刻画等方面具有明显的优势。目前,应用这套理论及方法开展精细地质建模和数值模拟依然存在挑战,需要进一步发挥地震资料作用并探索人工智能的地震解释新途径。 相似文献
82.
城市雨水地下回灌过程中悬浮物表面堵塞规律 总被引:1,自引:0,他引:1
雨洪资源地下回灌是缓解城市供水压力、解决地下水过量开采引起环境负效应的有效途径之一,但堵塞问题却是制约回灌技术推广的关键问题。基于前人理论,研究了入渗介质与悬浮物粒径中值之比(D50/d50)对堵塞层空间分布的影响。以建立表面堵塞预测模型为目的,利用城市雨水回灌细粒石英砂介质开展室内实验,观测雨水回灌的表面堵塞过程并获取渗透性变化的观测数据。根据物理、化学与生物堵塞的产生条件及堵塞特点,判断雨水回灌产生的堵塞性质为物理堵塞。引入过滤模型描述堵塞的发展过程,确定了模型用于模拟细砂表面堵塞的参数值:孔隙堵塞系数(α)为0.15 m2/kg,阻力增长系数(f′R′)为20 000 m/kg。在不改变以上2个参数值的条件下,用该模型模拟不同悬浮物粒径悬浊水回灌细粒石英砂的堵塞过程,取得了较好的拟合效果。此过滤模型可以用于模拟入渗介质与悬浮物粒径D50/d50值小于5的表面堵塞的发展过程,可定量预测堵塞对回灌速率的影响。 相似文献
83.
河北南部地区石炭一二叠系煤层煤种丰富,峰峰、邯郸矿区煤层的宏观煤岩类型以半亮煤和半暗煤为主;显微煤岩类型为微镜煤、微镜惰煤及微暗煤;煤的结构以细、中宽条带状结构为主,在半亮煤和半暗煤中最多;有机显微组分以镜质组最高,一般可占50%~91%,惰质组占10%~35%,壳质组含量一般不超过5%,对煤层气来说,这是比较有利的烃源条件:区内大淑村矿2煤的矿物质含量最低,其煤的吸附能力较其它矿区高;主煤层镜质组最大反射率具有北高南低的分布规律,揭示了煤的生烃强度具有由南向北逐渐增高的趋势。该区煤层气源岩不仅影响煤的生烃能力,还影响着煤层对甲烷的吸附能力和煤层气的开采能力。 相似文献
84.
Song Xuexin 《Mineralium Deposita》1984,19(2):95-104
The Fankou Pb-Zn deposit occurs in the Middle-Upper Devonian and Lower Carboniferous carbonate and argillaceous carbonate formations. In principle, the deposit can be classified as a carbonate-hosted strate-bound deposit. Representative sphalerite, galena, and pyrite separates from Fankou have been analysed. For the purpose of comparison a literature survey on minor elements of other districts have been carried out. The comparison of determined data with the quoted data shows that the Fankou sphalerites are rich in Ga, Ge and Ag, but poor in Se and Te; the Fankou galenas are rich in Ag, Hg, Sb and As, but poor in Se, Te, Tl and Bi; the Fankou pyrites are rich in As, Cd and In, but poor in Se, Te, Co and Ni. Zn/Cd and Se/S×10–4 ratios for sphalerites, Sb/Ag, Sb/Bi and Se/S×10–4 ratios for galenas and Co/Ni ratios for pyrites from Fankou and other districts have been calculated. Ga-Ge-Ag atomic ratios in sphalerites, Sb-Bi-Ag atomic ratios in galenas and Co-Ni relations in pyrites have been plotted. The average value (311) of Zn/Cd ratios for sphalerites from Fankou is similar to values of sphalerites from Gaobanhe, Heqing, Accesa and Broken Hill. The average Sb/Ag ratio (0.74) and the Sb-Bi-Ag atomic ratios in Fankou galenas are similar to those in the syngenetic galena from the British Island. The Ga-Ge-Ag atomic ratios for Fankou sphalerites are similar to those for the syngenetic sphalerites and Gorno sphalerites. The average Co/Ni ratio (1.1) for micro to fine-grained pyrites from Fankou laminated-bedded pyrite ore is similar to that (0.8) for the sedimentary pyrites from other districts. As to the fine to medium-grained pyrites from Fankou massive pyritic ores, their higher Co/Ni ratios (1.6–1.8) may relate to the fact that more Ni is lost than Co, during the reformation or recrystallization. Sphalerite, galena and pyrite from Fankou all are rather poor in Se and have very low values of Se/S×10–4, so they may bear no genetic relation to volcanism. To sum up, the following conclusions can be reached: (1) The Fankou deposit possesses some syngenetic features. (2) Evidently it differs from skarn type, hydrothermal type, and volcanogenic type deposits. (3) Surely it is a reformed sedimentary Pb-Zn deposit. 相似文献
85.
86.
基于非因果滤波器的多次波匹配相减方法(英文) 总被引:1,自引:0,他引:1
在常规多道匹配滤波方法中的滤波器是物理可实现的因果滤波器,只能实现地震信号序列延迟的滤波。本文提出了最小二乘意义下的非因果多道输入多道输出维纳滤波方法,通过比较多道匹配相减中因果和非因果滤波方法之间的差别,验证了方法的有效性,解决了模型数据滞后于实际数据的情况。而且,通过定义长度随偏移距和层速度变化的滑动时窗,解决了匹配时窗内同相轴数量随偏移距增大而增加的问题。并将上述方法应用到改进的扩展多道匹配相减去除多次波的方法中,利用Pluto1.5理论模拟数据,对非因果滤波器和变长度时窗的匹配相减方法进行测试,取得了很好的去除多次波后的地震数据。 相似文献
87.
Seagrass research in China is still in its infancy. Even though there has been progress recently, there is still a great deal
of research needed to gain a better understanding of seagrass. In this article we review and discuss the advances in seagrass
research in China from two aspects: (1) seagrass species and their distribution; (2) seagrass research in China, including
studies on their taxonomy, ecology, photosynthesis, applications in aquaculture, salt-tolerance mechanisms and other research
topics. A total of 18 seagrass species belonging to 8 genera are distributed in nine provinces and regions in China (including
Hong Kong and Taiwan), as well as the Xisha and Nansha Archipelagos. They can be divided into two groups: a North China Group
and a South China Group. Based on the seagrass distribution, the Chinese mainland coast can be divided into three sections:
North China Seagrass Coast, Middle China Seagrass Coast, and South China Seagrass Coast. Ecological studies include research
on seagrass communities, nutrient cycling in seagrass ecosystems, genetic diversity, pollution ecology and research in the
key regions of Shandong, Guangdong, Guangxi, and Hainan. Seagrass species and their locations, community structure, ecological
evaluation, epiphytes, ecological functions and threats in the key regions are also summarized. Other studies have focused
on remote sensing of seagrass, threatened seagrass species of China, and pollen morphology of Halophila ovalis. 相似文献
88.
This article presents the findings of a study of the spheres of urban influence with regard to all cities in China(not including Hong Kong,Macau and Taiwan Province of China)in the years 1990,2000 and 2009.An optimized gravity model with comprehensive time distance was used to carry out a detailed analysis of the spatial patterns of Chinese spheres of urban influence and the spatial characteristics of urban agglomerations.Such urban agglomerations are characterized by high density population and a developed economy,which are also considered as the national competition unit.This paper initially identifies four spatial patterns of urban agglomerations based on the spatial layout of city groups during their evolution.Some basic characteristics of urban agglomerations are outlined,including the number of cities,the size of cities and the functions of urban centers.These characteristics are examined by using statistical methods and Geographic Information System(GIS).The main findings from this research are that the development stages and structures of urban agglomerations in China vary significantly.It is also clear that the stages and evolution of spatial patterns are strongly affected and dominated by both policy and location factors. 相似文献
89.
90.
INTRODUCTIONThe study of surface subsidence resulting fromunderground mining holds significance in view ofbeneficial effects on national economy and people’sliving conditions.As is known,a large quantity ofminerals need to be exploited for modernization con-struction.Mining leads to surface subsidence,someunderground engineering and production facilities aredestroyed accordingly,which blocks the developmentof production and retards people’s living standard.To solve this contradiction,su… 相似文献