火星表面亮温的时空变化特征分析   总被引：1，自引：0，他引：1  

贾萌娜  邸凯昌  岳宗玉  孙姝娟 《遥感学报》2016,20(4):632-642

利用3个火星轨道器获取的热红外波段探测数据,分析了火星表面亮温在时间维上的年际和季节性变化规律,以及空间维上随地形和纬度的变化特征。研究结果表明:(1)5个火星年的表面亮温年际变化幅度均未超出轨道器热红外波段探测数据的精度范围。(2)火星南半球表面亮温的季节性变化幅度大,远日点时期表面亮温随季节的变化基本符合正弦规律且年际差异小,而近日点则有多处明显偏离正弦规律且年际差异较大;北半球表面亮温的季节性变化幅度远小于南半球,且季节特征不明显,受全球性尘暴影响而引起的夜间升温要大于夏季太阳辐射能增加引起的升温。(3)在同一时段,盆地、峡谷等低海拔地形的表面亮温较高,而山峰、高原、台地等高海拔地形的表面亮温一般较低;Olympus Mons地区的表面亮温与高程之间存在相关系数为–0.9072的负相关关系,线性拟合的结果表明该区域海拔每上升1 km,表面亮温下降约1.4 K。(4)表面亮温随纬度的变化总体上满足低纬度高于高纬度的规律,但受到地形等因素的影响,表面亮温最大值出现在偏离赤道的35°S位置,而赤道附近纬度的表面亮温最小值要小于临近稍高纬度位置的最小值;从赤道到两极同纬度表面亮温的差异逐渐减小。  相似文献   

Assessing thermal maturity of Palaeozoic rocks from reflectance of chitinozoa as constrained by geochemical indicators: an example from southern Ontario, Canada     

M. Obermajer  M.G. Fowler  F. Goodarzi  L.R. Snowdon 《Marine and Petroleum Geology》1996,13(8):907-919

The reflectance of chitinozoa (%ChR₀) was investigated as an alternative technique of determining the level of thermal maturity of organic-rich Palaeozoic rocks in southern Ontario. These sedimentary strata, which include the Ordovician Collingwood Member and the Blue Mountain Formation, as well as the Devonian Marcellus Formation, lack vitrinite precluding the application of a standard vitrinite reflectance (%VR₀) technique. ChR₀ shows a proportional increase at marginal to moderate maturities, being on average 20 to 25% higher than expected vitrinite reflectance. The reflectance data fall into a very narrow range showing a high degree of consistency for each lithostratigraphic unit. The average ChR₀ are as follows: Collingwood Mbr 0.63% (Georgian Bay area) and 0.88% (Toronto area), Blue Mountain Fm 0.92%, Marcellus Fm 0.68%. Correlation with more conventional optical and geochemical maturity parameters obtained from the same set of samples (fluorescence of Tasmanites, Leiosphaeridia and Gloeocapsomorpha alginite, Rock-Eval Tmax, extract data, distribution of terpanes and steranes in extracts) indicates that, within the area of study, the beginning of the catagenetic stage corresponds to ChR₀=0.65% (equivalent VR=0.50%) whereas the threshold of significant oil generation is reached at ChR₀=0.9% (equivalent VR=0.70%). Therefore the Blue Mountain Formation is thermally mature with respect to hydrocarbon generation throughout the whole area of study. The Collingwood shales are mature only in the Toronto area while those occurring in the Georgian Bay area as well as the Marcellus shales have yet to enter the main stage of hydrocarbon generation. This integrated approach of assessing thermal maturity shows that ChR₀, when constrained with other maturity parameters, is a very reliable indicator of thermal maturity in Lower to Middle Palaeozoic sedimentary rocks.  相似文献   

大别地块中的非镁铁质超高压变质岩石及其地质意义     

刘晓春  韩宗珠 《中国海洋大学学报(自然科学版)》1994,(4)

报道并描述了大别地块东南部几种新的非镁铁质超高压变质岩石，这些岩石的存在为区域规模的超高压变质作用提供了颇具说服力的证据。  相似文献   

大亚湾海域温排水三维数值模拟   总被引：3，自引：0，他引：3  

周巧菊 《海洋湖沼通报》2007,(4):37-46

为了研究大亚湾海域核电站温排水热污染问题,本文利用POM模式建立了大亚湾潮流三维数值模型,在模型验证良好的基础上,结合建立在对流扩散理论基础之上的输运扩散模型,对大亚湾核电站和岭澳核电站一期工程合排后夏季两核电站温排水的稀释扩散过程进行了数值计算,得到了涨憩、涨急、落憩、落急四个典型时刻温升场的特征值,并进一步分析了温升场的变化特征。  相似文献   

青岛榴辉岩相变质古洋壳的特征及其成因     

韩宗珠  武心尧  姚春明 《中国海洋大学学报(自然科学版)》1992,(4)

利用电子探针等方法研究了青岛榴辉岩相变质古洋壳(蛇纹岩、C类榴辉岩和基性糜棱岩)的岩石学和地球化学特征。确定了它们为华南陆块与华北陆块拼合前的古洋壳,当其俯冲于华北陆块之下时在深部发生碱质交代及低温高压变质作用(C类榴辉岩相)。  相似文献   

Simulation of the seasonal thermal structure in the Bohai Sea   总被引：1，自引：0，他引：1  

Huang Daji  Su Jilan  Chen Zongyong 《海洋学报(英文版)》1995,14(4):461-474

The seasonal thermal structure in the Bohai Sea are examined with a three-dimensional boroclinic primitive equation model for shelf sea.The evolution of the seasonal thermal stratification is well simulated.The stratification appears early in April,first in the area off Qinhuangdao and it is well developed in the middle of May.It intensifies with synoptic and neap-spring fluctuations throughout the summer and reaches its maximum in the middle of July.Eventually,it is destroyed at the end of September.There are cold water belts between well-mixed and stratified regions.They are loGated on the mixed side of tidal fronts,and coincide with the isolines for a temperature difference of 1-2℃ between surface and bottom.The sea surface temperature (SST) distribution shows local maxima at the head of three bays and to the south of Qinhuangdao during the summer.The Bohai Sea responds to the variability in the atmospheric forcing and in tides with the synoptic and neap-spring variations of SST,as well as in the stratification and in variable positions of tidal fronts.  相似文献   

Northern Adriatic Rocky Reef Fishes at Low Winter Temperatures   总被引：1，自引：0，他引：1  

Kurt  Kotrschal 《Marine Ecology》1983,4(3):275-286

Abstract. The behavioural ecology of certain northern Adriatic fishes was observed from January to April at a water temperature of 7–11 ^oC. The fishes studied here do not migrate to deeper waters. Most of the benthic fishes show a similar distribution over the substrate in winter and in summer; in winter, however, they are very inactive and hide in the substrate. Suprabenthic fishes aggregate in littoral caves where they form dense, inactive, mixed aggregations. Certain hemipelagic and pelagic fishes join to form very dense aggregations at specific sites in the open waters of bays. Littoral predators display high feeding activity at a time when their prey is inactive. I present a hypothesis concerning possible implications of seasonally cyclic environmental temperatures for a sympatric community of non-migrating fishes.  相似文献   

反厄尔尼诺事件的个例分析     

李若钝  邹娥梅  孙瑞本  刘丽惠 《热带海洋学报》1993,(2)

根据“中美热带西太平洋海-气相互作用联合考察”1—8航次考察资料、美国NOAA、日本气象厅及我国国家气象中心气候资料室提供的SST、水位和风场等资料,对1988—1989年反厄尔尼诺事件(La Nina)形成及发展过程和热带西太平洋海洋上层热结构的相互变化作了综合分析。文章指出在La Nina事件期间,热带太平洋的海、气参数均发生了相应的变化。热带西太平洋温跃层及热含量(0—150m)作出的响应,显示出当La Nina增强时,温跃层下降,热含量增加;La Nina盛期时,温跃层最深,热含量最大;La Nina减弱时,温跃层上升,热含量减小。它们与厄尔尼诺事件(El Nino)的关系则恰好相反。  相似文献   

Implications of estimated and measured thermal conductivity for oceanic heat flow studies     

Carol A. Stein  Dallas H. Abbott 《Marine Geophysical Researches》1991,13(4):311-329

Heat flow data provide constraints on the thermal structure and evolution of the oceanic lithosphere. Because precise determination of the heat flux requires that both the thermal gradient and the thermal conductivity be well determined we have examined the thermal conductivities used in a new Pacific Basin heat flow data set. 43% of the 1600 heat flow determinations rely on values estimated by various methods, rather than directly measured. Although the measured and estimated conductivities have comparable means, the measured conductivities have a standard deviation 50% larger than the estimated, suggesting that the estimated values underestimate the actual variation. We investigate the limitations of using such estimates by examining factors controlling the variations of measured conductivity values. We find that the variation between the closest adjacent sites increases with increasing separation, such that sites within 200 km are on average noticeably closer in conductivity than sites further apart. Contributing to this effect may be the variation of conductivity with lithology (with mean conductivity highest for carbonate oozes, intermediate for deep-sea clays, and least for siliceous oozes) and a possible trend of decreasing conductivity with increasing seafloor depth. Tests with the measured data suggest that the best method for estimating conductivity is using the mean value measured within 200 km. The mean of a larger geographical region is a somewhat poorer predictor, and using the oceanwide mean and the value at the nearest site are poorer still. Approximately 29% of the estimated values were not based on measurements from a reference site. For most others, the reference site was the nearest measurement from the same cruise, typically a large distance away. For those sites where conductivity was not measured, 78% had measured conductivity within 200 km and were reestimated using the local mean, whereas the remaining 22% were reestimated using the regional mean. The resulting change in the estimated conductivity averaged 9% using the local mean and 6% using the regional mean. We suggest that such a procedure be used to improve the utility of the heat flow data set, as an alternative to discarding the large fraction of the available data that does not incorporate measured conductivities.  相似文献   

Ocean thermal conditions in the post-smolt nursery of North American Atlantic salmon   总被引：2，自引：2，他引：2  

Friedland  Kevin D; Reddin  David G; Castonguay  Martin 《ICES Journal of Marine Science》2003,60(2):343-355

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