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701.
东海赤潮高发区水体光谱吸收特性分析   总被引:1,自引:0,他引:1  
赤潮是海洋中一种复杂的生态异常现象。赤潮的爆发、不仅严重影响近海景观,破坏水产养殖,危害人体健康,还对海洋生态平衡造成破坏,给人类造成惨重经济损失。近年来,在我国的赤潮观测记录中,赤潮的年发生次数逐渐增加,且面积不断增大,因此,对赤潮的发生发展机理及预测治理研究是科学家刻不容缓的研究课题。 赤潮发生时,赤潮生物大量聚集,使水体颜色发生明显变化,进而赤潮水体的光谱特征发生变化,且存在差异,使利用水色遥感监测赤潮成为可能,还可以用来区分赤潮种类的不同。水体光谱的变化特性(包括吸收与散射特性)是水色赤潮遥感监测的基础,是水色遥感生物光学算法开发的重要组成部分。因此对赤潮水体进行光谱吸收特性的分析研究对于发展研究海区的水色遥感生物光学算法及赤潮遥感监测方法都有重要意义。  相似文献   
702.
703.
Chen  Xi  Zhao  Sihao  Wang  Menglu  Lu  Mingquan 《GPS Solutions》2016,20(4):837-847
GPS Solutions - Known as China’s first low earth orbit (LEO) mobile communication experimental satellite, the LING QIAO satellite was launched on September 4, 2014. In addition to the two...  相似文献   
704.

Abundant natural gas inclusions were found in calcite veins filled in fractures of Central Fault Belt across the centre of Ordos Basin. Time of the calcite veins and characteristics of natural gas fluid inclusion were investigated by means of dating of thermolum luminescence (TL) and analyzing stable isotope of fluid inclusion. Results show that natural gas inclusion formed at 130–140°C with salinity of 5.5 wt%–6.0 wt% NaCl. It indicates that natural gas inclusion is a kind of thermal hydrocarbon fluid formed within the basin. Method of opening inclusion by heating was used to analyze composition of fluid inclusion online, of which the maximal hydrocarbon gas content of fluid inclusion contained in veins is 2.4219 m3/t rock and the maximal C1/ΣC i ratio is 91%. Laser Raman spectroscopy (LRS) was used to analyze chemistry of individual fluid inclusion in which the maximal hydrocarbon gas content is 91.6% compared with little inorganic composition. Isotope analysis results of calcite veins show that they were deposited in fresh water, in which the δ 13CPDB of calcite veins is from −5.75‰ to 15.23‰ and δ 18OSMOW of calcite veins is from 21.33‰ to 21.67‰. Isotope results show that δ 13C1 PDB of natural gas fluid inclusion is from −21.36‰ to −29.06‰ and δDSMOW of that is from −70.89‰ to −111.03‰. It indicates that the gas of fluid inclusion formed from coal source rocks and it is the same as that of natural gas of Mizhi gas reservoir. Results of TL dating show that time of calcite vein is (32.4±3.42)×104 a, which is thought to be formation time of gas inclusion. It indicated that natural gas inclusion contained in calcite veins recorded natural gas leakage from Mizhi gas reservoir through the Central Fault Belt due to Himalayan tectonic movement.

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705.
?????????????????????GPS???????,??????????????Ms8.1??????????????λ???????????????????仯??????????????????????????:1???????????????й??????α??????????,??????????????????????γ????????????????;2?????????????????????粿?γ????????????????????????5.9?????????5.4???????????????????γ??????β??????????;3????????????嶫?????????????巴??,????????Χ???????嶫??????????????????????;4????????????????????????????????Щ??????  相似文献   
706.
Headwater storage–discharge (S–Q) remains one of the least understood processes, and there is renewed interest in the S–Q relation. How well can the S–Q relation be interpreted mechanistically using geometric factors? In this paper, the hillslope storage Boussinesq and hillslope storage kinematic wave equation were adopted to guide the theoretical derivations. Analytical solutions were derived based on the hsKW equation for nine idealized hillslope aquifers, which were subdivided into two groups, i.e. hillslope aquifers with exponential hillslope width function (C1) and hillslope aquifers with Gaussian hillslope width function (C2). We found that analytical expressions of the S–Q relation can be derived for C1 hillslope aquifers. For more compound hillslope aquifers, i.e. C2, no explicit S–Q relation can be obtained. The whole subsurface recession after a rainstorm is simulated by applying the initial saturation condition. We found that the simulated S–Q processes can be characterized by a two‐phase recession, i.e. quick and slow recession. The time (tb) at the dividing point of the quick and slow recessions depends on the geometric factors, such as the plan and profile curvature. In the quick recession for C1, many of the S–Q curves can be described as linear or quasi‐linear functions, which indicate that linear reservoir models can be applied approximately for recession simulations. However, during the slow recession phase of C1 and during the whole recession of C2, the S–Q relations are highly non‐linear. Finally, we compared the hillslope storage kinematic wave and hillslope storage Boussinesq models for simulating subsurface water recession after a rainstorm event in a real‐world headwater catchment (G5) in China. Through comparison of the recession slope curves, we found that the simulated results of the models employing the Gaussian hillslope width function match the observed hydrograph. The results indicated that appropriate organization of the hillslope geometric factors enhances our ability to make S–Q predictions. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
707.
致密砂岩储层是油气勘探的重点方向之一,由于致密砂岩储层具有低孔低渗、孔隙结构复杂、非均质性强和岩电参数变化等特点,在测井解释过程中不同于常规储层。Archie公式在致密砂岩地层中使用时,强非均质性导致岩电参数abmn会随着储层的变化而变化。针对苏里格西区盒8段致密砂岩储层提出利用变岩电参数建立饱和度模型。依据研究区盒8段储层25块岩心岩电实验分析发现胶结系数m与lgϕ呈二次函数关系、m与岩性系数a呈幂函数关系、束缚水饱和度Swb对饱和度指数n有较大的影响。因此,在对孔隙度、束缚水饱和度和孔隙结构指数等因素分析的基础上,综合各因素影响特征建立了变岩电参数的饱和度模型。结果表明,该方法相对传统Archie公式饱和度解释,模型精度更高,为解释复杂孔隙结构砂岩储层提供了一种有效预测方法。  相似文献   
708.
      凝灰岩致密油藏作为一种特殊的油藏类型,已受到高度关注,而烃源岩的质量对致密油藏形成起着至关重要的作用.为了研究新疆三塘湖盆地马朗凹陷石炭系火山岩油气藏成藏规律,本文在基本地质特征研究的基础上,通过岩石样品的岩石热解、干酪根碳同位素和饱和烃色质谱等分析测试,对马东地区卡拉岗组不同岩性烃源岩特征进行描述与评价.研究结果表明:凝灰质泥岩和白云质泥岩均具有一定生烃潜力,其中凝灰质泥岩生烃潜力大,有机质丰度高,总有机碳质量分数平均值大于2%,以Ⅱ型有机质为主;卡拉岗组烃源岩埋藏深度较小,镜质体反射率主要分布在0.5%~0.8%,总体上处于低熟—成熟阶段.纵向上各种岩性烃源岩与凝灰岩交错叠置,有利于形成源内自生自储型油藏,对卡拉岗组致密凝灰岩油藏的形成具有重要意义.  相似文献   
709.
As a new type of pollutants in the marine environment,microplastics have attracted increasing attention from scientific researchers and environmental protection workers in China and abroad.However,for the microplastic pollution in sea areas in China,there are a very limited number of studies on its current status and few reviews of research on the microplastics.This paper reviews the surveys and researches of microplastics in the Bohai Sea,the Yellow Sea,the East China Sea,the South China Sea,and main estuaries in China carried out in recent years and proposes an outlook for future work,aiming to provide research suggestions and solutions for ecological protection against microplastic pollution in sea areas in China.Previous studies have shown that microplastics are widely distributed in water bodies and sediments in sea areas and major estuaries in China.The Pearl River Estuary,in the South China Sea suffers the most serious microplastic pollution,followed by the Bohai Sea.In contrast,the microplastic pollution in the Yellow Sea and the East China Sea is comparatively slight.Microplastics in sea areas in China are mainly fibrous and are concentrated in offshore areas with developed industry and a dense population(especially around estuaries and bays).In addition,they are widely affected by human activities,such as shipping,aquaculture,industry,and sewage discharge.Here the authors suggest unifying measurement units and research methods and developing related standard systems to carry out researches related to microplastics.Furthermore,this paper also suggests further deepening researches on both the source-sink process of microplastics and nanoscale microplastics while enhancing the development and implementation of related policies,aiming to promote researches and control of microplastics in sea areas in China.  相似文献   
710.
包建平  朱翠山  杨茜 《地质学报》2023,97(8):2659-2675
借助色谱- 质谱(GC- MS)和色谱- 质谱- 质谱(GC- MS- MS)分析,对黔南坳陷凯里残余油藏凯棠和洛棉剖面上储层沥青中的烃类组成进行了系统分析,以判断其所遭受生物降解作用的程度,探寻在极端降解原油中是否还存在原生生物标志物,为这类原油的油源研究开拓新的途径和方法。结果表明:凯棠剖面上的储层沥青中尽管仍可检测到较为完整的C19- 30三环萜烷和C27- 35藿烷系列,但C19- 29脱甲基三环萜烷系列和C26- 34 25- 降藿烷系列丰富而完整,甾烷系列中C21- 22低分子量甾烷和重排甾烷优势明显,这一系列特征表明这些沥青遭受了剧烈生物降解作用的改造。但三芳甾类仍保存完好,依据原油生物降解程度的评判标准,判断其生物降解级别介于8~9级之间。洛棉剖面上的储层沥青中藿烷系列基本消失殆尽,三环萜烷系列及其脱甲基产物和25- 降藿烷系列的分布因极端生物降解作用而发生显著变异,某些化合物如C23T、C24T、C23NTE和C28- 29NH成为优势成员;甾烷系列中C21- 22低分子量甾烷占绝对优势,三芳甾类完全消失,据此判断该剖面上沥青的生物降解级别已达到10级或更严重。由于这两个剖面上的沥青遭受了极端生物降解作用的改造,常用的甾、萜类生物标志物完全失去了实用价值。但是,在所分析的这些沥青中都检测到三个系列的C27- 35 8,14- 开环藿烷系列,它们与塔里木盆地塔中地区海相端元油中存在的同类标志物的分布特征相似。正常海相端元油和极端生物降解沥青中同时检测到这三个系列的8,14- 开环藿烷,这一事实表明这类生物标志物在成因上具有原生性,而与生物降解作用无关。此外,在极端生物降解作用沥青中的完好保存,表明它们具有极强的抗生物降解能力,因而它们在此类原油的油源研究中可能具有潜在的实用价值。  相似文献   
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