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61.
刘晓丽 《沉积与特提斯地质》2021,41(1):100-105
通过岩石学、沉积学及测井等方法,对准噶尔盆地TX1井区侏罗系八道湾组一段进行详细研究,认为侏罗系八道湾组一段主要发育复成分砾岩、砾状砂岩及砂岩,煤夹层;沉积构造发育,兼具水上及水下沉积的特点,发育粒序层理、中大型交错层理及冲刷充填、植物枝干印模等沉积构造;测井上具箱型、漏斗型、指状、线性等响应。沉积相纵向上逐渐向盆地边缘退积演化,其中三角洲平原亚相在2~5砂组较为发育,以辫状分流河道及河道间的河漫沼泽沉积为主,前缘亚相在1砂组较为发育,以水下分流河道及支流间湾沉积为主。辫状河三角洲前缘水下分流河道微相是最有利的储集相带,孔渗结构较优,原油含水率低;辫状河三角洲平原分流河道微相次之,其储层非均质性强,原油含水率较高。 相似文献
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通过1:5万水系沉积物的地球化学测量,对查哈西里地区Au、Cu等16种元素的地球化学特征进行了初步分析.综合元素富集程度、分异程度、叠加强度,发现Au、Cu、Ni、Cr、Co在研究区内有富集成矿的可能,是研究区主要成矿元素.根据异常特征与成矿地质条件,推断区内为构造蚀变岩型Au-Cu多金属矿床及热液蚀变型Cu-Ni多金属矿床.优选出4处成矿远景区,即科德日特-巴嘎哈尔散金铜多金属成矿远景区、查干热格沟铜多金属成矿远景区、乌兰可镍多金属成矿远景区和马尼特沟南铁镍多金属成矿远景区. 相似文献
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利用地面气象常规观测资料、区域自动站观测资料、雷达及卫星资料和NCEP 1°×1°的逐6h再分析资料,对2018年5月13日攀西地区南部的飑线天气过程的形成机制进行分析。结果表明:飑线发生在高空槽前,高空槽逐渐东移推动冷性气流沿背风坡东移,然后与前方低层暖空气汇合抬升形成对流;露点锋触发了飑线天气过程的形成;产生飑线天气区域的大气具有上干下湿、不稳定能量高、垂直风切变强、高层风速大和形成之前存在逆温层的特点;高空急流和动量下传对飑线的发生和加强具有促进作用;地形对飑线的形成和天气现象的分布有影响。 相似文献
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Abstract Knowledge of the hydrochemical dynamics of the trace metal manganese (Mn) in upland catchments is required for water quality management. Stream water Mn and other solutes and flow were monitored in two upland catchments in northern England with different soils: one dominated by peat (HS7), the other by mineral soils (HS4). Maximum Mn concentrations occurred at different times in the two catchments: in summer baseflow at HS4 and during late summer storm events at HS7. A two-component chemical mixing model was used to identify the hydrological processes controlling Mn concentrations in stream water. This approach was more successful for HS4 than HS7, probably because of different processes of Mn release in the two catchments and also difficulties in selecting conservative solutes. Factor analysis of the stream water chemistry data set for each catchment was more useful in identifying the controls on Mn release into runoff. The factors indicate that the main source of Mn at HS4 is the hydrological pathway supplying summer baseflow, whereas at HS7 Mn is released during the rewetting of dried peat soils. Manganese concentrations in stream water in upland catchments appear to depend on soil type and antecedent moisture conditions. This has implications for the design of sampling strategies in upland catchments and also for managing the quality of water supplies from such areas. 相似文献
66.
《水文科学杂志》2013,58(3)
Abstract Abstract Generating pulses and then converting them into flow are two main steps of daily streamflow generation. Three pulse generation models have been proposed on the basis of Markov chains for the purpose of generating daily intermittent streamflow time series in this study. The first one is based on two two-state Markov chains, whereas the second uses a three-state Markov chain. The third model uses harmonic analysis and fits Fourier series to the three-state Markov chain. Results for a daily intermittent streamflow data series show a good performance of the proposed models. 相似文献
67.
Stream temperature and riparian microclimate were characterized for a 1·5 km wildfire‐disturbed reach of Fishtrap Creek, located north of Kamloops, British Columbia. A deterministic net radiation model was developed using hemispherical canopy images coupled with on‐site microclimate measurements. Modelled net radiation agreed reasonably with measured net radiation. Air temperature and humidity measured at two locations above the stream, separated by 900 m, were generally similar, whereas wind speed was poorly correlated between the two sites. Modelled net radiation varied considerably along the reach, and measurements at a single location did not provide a reliable estimate of the modelled reach average. During summer, net radiation dominated the surface heat exchanges, particularly because the sensible and latent heat fluxes were normally of opposite sign and thus tended to cancel each other. All surface heat fluxes shifted to negative values in autumn and were of similar magnitude through winter. In March, net radiation became positive, but heat gains were cancelled by sensible and latent heat fluxes, which remained negative. A modelling exercise using three canopy cover scenarios (current, simulated pre‐wildfire and simulated complete vegetation removal) showed that net radiation under the standing dead trees was double that modelled for the pre‐fire canopy cover. However, post‐disturbance standing dead trees reduce daytime net radiation reaching the stream surface by one‐third compared with complete vegetation removal. The results of this study have highlighted the need to account for reach‐scale spatial variability of energy exchange processes, especially net radiation, when modelling stream energy budgets. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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本文利用常规探测资料,分析了1983年3月25日发生在珠江三角洲地区的一次强对流天气过程背景流场的几个重要特征,如高空急流的结构与变化、辐散风场及与之相联系的背景次级环流、风场垂直切变和水平切变等. 相似文献