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131.
昭通太阳背斜山地浅层页岩气"三维封存体系"富集成藏模式 总被引:3,自引:0,他引:3
本文系统分析了太阳地区构造断裂系统、顶底板条件、沉积岩相、优质页岩展布、源储条件及富集高产规律,提出了"多场协同多元耦合"共同作用下太阳背斜区山地浅层页岩气"三维封存体系"富集成藏赋存模式,具有5个特征:①页岩储层上覆龙马溪组一段二亚段—石牛栏组厚层致密页岩和泥灰岩,下伏临湘组—宝塔组厚层致密瘤状灰岩,具有良好的封隔层条件,形成了封存体系的顶板和底板;②压扭应力背景下形成的断裂系统属于挤压性逆冲断层、压扭性走滑断层,断层的纵向封闭性好,有效地保护了优质页岩气藏;③断层两盘页岩气层对接岩性均为致密泥灰岩和灰岩,侧向封堵性防止了页岩气泄漏点出现,使得山地浅层页岩气仍具有连续型气藏特征;④前陆盆地"水体滞留+火山灰沉降"造就了"海洋漂浮生物繁盛+缺氧强还原"深水陆棚沉积环境,形成了"富碳、高硅、低黏、高脆"的优质烃源岩储集体,构建了"规模生烃、高效吸附富集"的页岩微纳米级储集孔隙空间;⑤页岩储层具有相对小的地应力和两向水平应力差,既利于在中低泵压下的储层压裂施工作业,又具备体积压裂打碎页岩形成复杂缝网和气井获得高产的关键要素.提出了复杂构造区山地浅层页岩气"多元富集高产"的规律性认识,即:前陆盆地深水缺氧强还原环境促使了"富碳、高硅、低黏"页岩储层发育(沉积成岩控制源储特征)、持续良好的三维封闭保存体系有效保护了富有机质页岩生烃留烃富烃和超压保孔(保存条件控制天然气藏)、页岩脆性与地应力以及水平应力差决定了体积压裂改造的难易程度并影响了人造页岩气藏的构建效果(应力可压性控制人造气藏)、Ⅰ类优质页岩气储层连续厚度和地层压力系数决定了页岩气禀赋的资源储量丰度与气井高产(烃储禀赋控制单井产量).研究成果对中国南方复杂构造区海相浅层页岩气的高效勘探开发具有重要的借鉴引领和指导意义. 相似文献
132.
闭流坳陷湖盆的气候层序 总被引:1,自引:0,他引:1
闭流坳陷湖盆以发育气候层序为特征,在理想条件下,气候三级周期的变化基本符合正弦曲线;一个完整的闭流坳陷湖盆气候层序Ⅰ型层序应包括4个体系域:低水位进积楔体系域、水进体系域、高位体系域和强制水退楔体系域;同样一个完整的闭流坳陷湖盆气候层序Ⅱ型层序应包括3个体系域:水进体系域、高位体系域和强制水退边缘体系域。这些体系域在气候周期变化的曲线上有相应的位置,层序界面则位于基准面变化的最低点。 相似文献
133.
采用闭合循环实验方法,观测了厦门西港底质耗氧过程。结果显示底质耗氧随时间变化呈非线性,可用指数方程SOD=ρ·exp(—k/t)表示.计算得厦门西港底质耗氧速率均值为405.8mg/(m~2·d)。在底质耗氧过程中,底质释放出有机物质,底质释放COD 速率为93.6mg/(m~2·d),底质耗氧作用与底质有机物质的释放有关. 相似文献
134.
Robert G. Bryant 《地球表面变化过程与地形》1999,24(4):283-302
The importance of monitoring changes in the levels of lakes within endorheic basins using remotely sensed data as a means of assessing changes in regional aridity is noted. Large salt playas are highlighted as ephemeral lakes that can display extreme sensitivity to changes in regional rainfall patterns, and which commonly do not have extensively managed catchments. To explore the application of high temporal frequency monitoring of salt playas using remote sensing, the Chott el Djerid, a large salt playa situated in southern Tunisia was targeted. A short time series of 39 Advanced Very High Resolution Radiometer (AVHRR; resolution 1.1 km at nadir) images of the Chott el Djerid (spanning 36 months between 1987 and 1990) were compiled along with climate information from a weather station at Tozeur. Using image histogram manipulation, lake areas were extracted from the time series. A good level of agreement was observed between recorded rainfall events and the presence of surface water on the playa, and for a limited sample of large flood events it was found that there were significant relationships between rainfall, evaporation and estimated lake areas (r2 = 98.5, p < 0.001). Overall, these data suggest that contemporary lake formation is largely controlled by temporal changes in effective precipitation within the basin. In addition, it was found that the coefficient of variation of the time series, and a combination of temporal reflectance profiles extracted from it, could be used to give a direct indication of which sedimentary surfaces on the playa are affected by large flood events, and the extent to which these events may be preserved within the recent sedimentary record at these sites. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
135.
Wei Dong Guo 《国际地质力学数值与分析法杂志》2000,24(2):135-163
Viscoelastic or creep behaviour can have a significant influence on the load transfer (t–z) response at the pile–soil interface, and thus on the pile load settlement relationship. Many experimental and theoretical models for pile load transfer behaviour have been presented. However, none of these has led to a closed‐form expression which captures both non‐linearity and viscoelastic behaviour of the soil. In this paper, non‐linear viscoelastic shaft and base load transfer (t–z) models are presented, based on integration of a generalized viscoelastic stress–strain model for the soil. The resulting shaft model is verified through published field and laboratory test data. With these models, the previous closed‐form solutions evolved for a pile in a non‐homogeneous media have been readily extended to account for visco‐elastic response. For 1‐step loading case, the closed‐form predictions have been verified extensively with previous more rigorous numerical analysis, and with the new GASPILE program analysis. Parametric studies on two kinds of commonly encountered loading: step loading, ramp (linear increase followed by sustained) loading have been performed. Two examples of the prediction of the effects of creep on the load settlement relationship by the solutions and the program GASPILE, have been presented. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
136.
137.
Shaw‐Wen Sheen 《The Professional geographer》2000,52(3):397-406
In this paper, I develop global karst chemical denudation models using chemical equilibrium equations. Theoretical karst chemical denudation rates are calculated as soil carbon dioxide concentration varies from 10?3.5 atm to 10?1.0 atm, temperature varies from 0°C to 30°C, and annual runoff varies from 500 mm to 3,000 mm. Both open and closed karst solution systems are examined. The Drake (1980) and the Brook‐Folkoff‐Box (1983) soil pCO2 equations are used to develop chemical denudation models for different carbonate rocks (limestone and dolomite), climate (tropical, temperate, and arctic/alpine terrains), and karst solution type (open and closed systems). The major conclusion is that the karst solution type, least known in the past karst studies, is an important factor in controlling chemical denudation rates. 相似文献
138.
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??????С????????????????????????????????????????????????????????????????????????????·?????????????????????????????????С?????????????????????GPS???????????????????????????????÷??????????? 相似文献
139.
低温条件下饲料的脂肪含量对石斑鱼生长的影响 总被引:2,自引:0,他引:2
为了研究在低温条件下饲料中的脂肪含量对石斑鱼生长的影响,制作脂肪含量为7.53%(G1)、9.52%(G2)、13.27%(G3)和16.64%(G4)的石斑鱼试验饲料,在闭路循环水16.1~21.3℃的低温下养殖石斑鱼,试验结束时称重并进行生物学指标和氨基酸的测定,结果表明低温对鱼类的生长性能产生了一定程度的影响,低温条件下,随着脂肪含量的升高,实验石斑鱼的增重率、肝脂率、肌脂率有明显程度的提高,而肝体比、脏体比相应的降低,摄食G1、G2实验饲料的石斑鱼为负增长,其肝脂率和肌脂率显著高于摄食G3、G4实验饲料的石斑鱼,而肝体比、脏体比却显著的低于后者,肌肉蛋白含量、水分及消化道指数无显著差异,死亡率随着脂肪含量的升高呈降低的趋势,各组石斑鱼肌肉的氨基酸组成差异不大,仅表现为酪氨酸随着脂肪添加量的增加减少的趋势,本实验说明了低温条件下适当增加饲料中的脂肪含量有利于保持石斑鱼的生长,同时为鱼类的越冬期及低温胁迫下的管理提供了1种可行的营养供给策略。 相似文献
140.
Akash Anandraj Renzo Perissinotto Christian Nozais Derek Stretch 《Estuarine, Coastal and Shelf Science》2008,79(4):599-606
Mouth breaching is a recurrent event in temporarily open/closed estuaries (TOCEs). Such disturbances result in flushing and sediment scouring, reducing the microalgal biomass stock. The depletion of these microalgae may have negative repercussions in the form of depleted stocks of commercial fish, game fish, crustaceans and mollusks. The aim of this investigation was therefore: (1) to monitor the recovery of microalgal biomass and production following a breaching event; and (2) to determine the key environmental parameters influencing primary production during the open and recovery phases. Phytoplankton and benthic microalgal production was measured (14C-uptake method) successively during the closed, open and recovery phases of the Mdloti TOCE (South Africa). Upon breaching, 94–99% of microalgal biomass was washed out to sea through flushing and sediment scouring. A temporary recovery of phytoplankton and benthic microalgal biomass was observed during the open phase, but this was not sustained because of continual flushing and scouring of the sediment. During the re-closure (recovery phase), microalgal biomass immediately increased, reaching pre-breaching levels 35–40 days following the breaching event. In contrast to biomass, autochthonous pelagic primary production reached a maximum level (341 mg C m−2 h−1) during the open phase. Pelagic primary production normalized to biomass (PB) significantly increased during the open phase. This is attributed to a favorable combination of optimum light conditions, high influx of macronutrients and high water temperatures (33 °C). Similarly, benthic primary production normalized to biomass (PB) peaked during the open phase (35 mg C mg chl-a−1 h−1). Multivariate analysis showed that major variations in primary production were mainly controlled by temperature, dissolved inorganic nitrogen (DIN) to phosphorus (DIP) molar ratios (water-column and pore-water) and light extinction (Kd), all of which were regulated by the state of the mouth. 相似文献