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61.
流动单元的研究,其目的在于对油藏的非均质性有进一步的认识,为提高油藏描述的精度提供依据。本文根据流动单元的理论,选取适合该区实际的参数,应用聚类判别分析的方法,对华池油田陇东地区长33低渗储层进行分类研究,并且分析各类流动单元的特征及其控制因素,得出结论:该区储层可分为三类流动单元,各类流动单元的判别公式,不同的类型在动态、静态上有不同的表现;其分布的差异,宏观上受沉积微相的控制,微观上受成岩作用、岩石自身储集空间特征的限制。  相似文献   
62.
大庆油田葡萄花油层组储层非均质性主控因素分析   总被引:6,自引:0,他引:6       下载免费PDF全文
本文对萨尔图油田中部葡萄花油层组的非均质性进行定量半定量研究,认为葡萄花油层组PⅠ2小层层内非均质性最严重,与沉积微相密切相关;单砂层垂向上渗透率的变化以正韵律和复合式韵律为主,局部发育反韵律模式;层内非均质性强弱依次为PⅠ2a、PⅠ3、PⅠ2b、PⅠ1、PⅠ4;层间非均质性在PⅠ3和PⅠ4间表现得最强,其它相对要弱;各小层平面非均质性相差无几,整体表现为较强的非均质性。  相似文献   
63.
An explosion in a borehole or an accidental explosion in a tunnel will generate a two-dimensional (2-D) compressive wave that travels through the surrounding rock mass. For the problem of 2-D compressive wave propagation in a rock mass with parallel joints in the radial direction normal to the joints, parametric studies on the transmission ratio and the maximum rebound ratio are performed in universal distinct element code. The variation of the transmission ratio with the ratio of joint spacing to wavelength is generalized into a characteristic curve, which can be used as a prediction model for estimating the transmission ratio. The relationship between the maximum rebound ratio and the influence factors is obtained in charts. The charts can be used as a prediction model for estimating the maximum rebound ratio. The proposed prediction models for estimating the transmission ratio and the maximum rebound ratio are applied to a field explosion test, Mandai test in Singapore. The minimum possible values of peak particle velocity (PPV) at the monitoring points are estimated by using the proposed prediction model for estimating the transmission ratio along the radial direction normal to the joints. On the other hand, the maximum possible values of PPV are estimated by using the proposed prediction model for estimating the maximum rebound ratio along the same radial direction. The comparison shows a good agreement between the field-recorded PPVs and the estimated range of PPVs given by the minimum possible PPVs and the maximum possible PPVs at the monitoring points in Mandai test. The good agreement between the estimated and field-recorded values validates the proposed prediction models for estimating peak particle velocity in a rock mass with a set of joints due to application of a compressive wave at the boundary of a tunnel or a borehole.  相似文献   
64.
安哥拉下刚果盆地吉拉索尔深水油田   总被引:4,自引:2,他引:4  
吉拉索尔油田位于西非安哥拉17号深水区块,水深1200~1400m,距安哥拉海岸150km。1996年发现,2001年产油,是安哥拉投入开发的第一个深水油田。油田面积约140km2,地质储量约为15.5×108bbl,可采储量约7.25×108bbl,为轻质油。油田所在的下刚果盆地主要经历了裂谷期、过渡期和热沉降期三个阶段的构造演化,相应沉积了裂谷期陆相地层、过渡期蒸发岩层和热沉降期海相地层。主要烃源岩为下白垩统Bucomazi组湖相页岩,有机质丰度高,类型好,成熟度适中,为很好的烃源岩。盆地深水区主要储层为上渐新统—中新统河道充填浊积砂岩复合体,砂岩固结差,物性良好。吉拉索尔油田主要由几个河道浊积砂岩复合体叠置组成,其中夹几个薄层席状砂岩,复合体之间被海相泥页岩分隔。上覆第三系泥岩为其主要盖层。  相似文献   
65.
The Miocene–Quaternary Jemez Mountains volcanic field(JMVF) is the site of the Valles caldera and associated BandelierTuff. Caldera formation was preceded by > 10 Myr of volcanismdominated by intermediate composition rocks (57–70% SiO2)that contain components derived from the lithospheric mantleand Precambrian crust. Simple mixing between crust-dominatedsilicic melts and mantle-dominated mafic magmas, fractionalcrystallization, and assimilation accompanied by fractionalcrystallization are the principal mechanisms involved in theproduction of these intermediate lavas. A variety of isotopicallydistinct crustal sources were involved in magmatism between13 and 6 Ma, but only one type (or two very similar types) ofcrust between 6 and 2 Ma. This long history constitutes a recordof accommodation of mantle-derived magma in the crust by meltingof country rock. The post-2 Ma Bandelier Tuff and associatedrhyolites were, in contrast, generated by melting of hybridizedcrust in the form of buried, warm intrusive rocks associatedwith pre-6 Ma activity. Major shifts in the location, styleand geochemical character of magmatism in the JMVF occur withina few million years after volcanic maxima and may correspondto pooling of magma at a new location in the crust followingsolidification of earlier magma chambers that acted as trapsfor basaltic replenishment. KEY WORDS: crustal anatexis; fractional crystallization; Jemez Mountain Volcanic Field; Valles Caldera; radiogenic isotopes; trace elements  相似文献   
66.
焦明若  张国民 《地震》1998,18(1):14-20
通过国内外成功与失败的震例分析,介绍了地震前兆共性的一面,如在台网具有一定监测能力的地区,如果发生6级以上地震,震前总能或多或少地观测到异常现象。地震越大震前异常越多,分布越广,持续时间越长,异常幅度也较大,同时章着重对前兆复杂性的表现形式进行了较系统的归纳,整理,主要从以下几方面进行了分析,异常与地震关系的不确定性,主要表现在除了“有异常有地震”和“无异常无地震”的理论情况外,还存在“有异常无  相似文献   
67.
The regional dynamical model of the atmospheric ozonosphere   总被引:1,自引:0,他引:1  
TheRegionalDynamicalModeloftheAtmosphericOzonosphereWangWeiguo(王卫国),XieYingqi(谢应齐)DepartmentofEarthscience.YunnanUniversity,K...  相似文献   
68.
利用现场可编程门阵列(FPGA)的内部资源,在FPGA中实现了高精度时间间隔测量系统的设计。  相似文献   
69.
本文是世界各国日像仪的天线阵性能汇集,包括日、俄、法、中、美等专用日像仪及美国、印度、巴西等兼作日像仪的天线阵,列出了几个典型天线阵列排列及接收系统。附录中列出了等口径及不等口径天线阵列的灵敏度及动态范围计算公式,同时列出了视场、角分辨率等公式。便于读者自行分析,计算,比较各天线阵列性能。  相似文献   
70.
Forthcoming human planetary exploration will require increased scientific return (both in real time and post-mission), longer surface stays, greater geographical coverage, longer and more frequent EVAs, and more operational complexities than during the Apollo missions. As such, there is a need to shift the nature of astronauts’ scientific capabilities to something akin to an experienced terrestrial field scientist. To achieve this aim, the authors present a case that astronaut training should include an Apollo-style curriculum based on traditional field school experiences, as well as full immersion in field science programs. Herein we propose four Learning Design Principles (LDPs) focused on optimizing astronaut learning in field science settings. The LDPs are as follows:
(1)
LDP#1: Provide multiple experiences: varied field science activities will hone astronauts’ abilities to adapt to novel scientific opportunities
(2)
LDP#2: Focus on the learner: fostering intrinsic motivation will orient astronauts towards continuous informal learning and a quest for mastery
(3)
LDP#3: Provide a relevant experience—the field site: field sites that share features with future planetary missions will increase the likelihood that astronauts will successfully transfer learning
(4)
LDP#4: Provide a social learning experience—the field science team and their activities: ensuring the field team includes members of varying levels of experience engaged in opportunities for discourse and joint problem solving will facilitate astronauts’ abilities to think and perform like a field scientist.
The proposed training program focuses on the intellectual and technical aspects of field science, as well as the cognitive manner in which field scientists experience, observe and synthesize their environment. The goal of the latter is to help astronauts develop the thought patterns and mechanics of an effective field scientist, thereby providing a broader base of experience and expertise than could be achieved from field school alone. This will enhance their ability to execute, explore and adapt as in-field situations require.  相似文献   
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