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41.
玻璃钢百叶箱与木制百叶箱内温湿度测量的对比分析   总被引:9,自引:1,他引:9  
通过分析2005年2—7月玻璃钢百叶箱与木制百叶箱内温湿度对比试验资料,得到了两种材料百叶箱内温湿度测量的差异以及两种百叶箱间对大气温湿度变化反应速度的差异,并分别讨论了不同云量、不同风速条件下,两种材料百叶箱气温测量差值的变化。结果表明:两种材料百叶箱内测量的气温平均差值在0.1℃以内,差值标准差在0.2℃以内,相对湿度平均差值在0.4%以内,差值标准差在2.1%以内;玻璃钢百叶箱对大气温湿度的反应比木制百叶箱快或相当;无论在多云和少云条件下,还是高风速和低风速条件下,两种百叶箱内测量的气温差值普遍在0.1℃以内。  相似文献   
42.
The Fe2+–Mg distribution coefficients between sapphirine and spinel:
were experimentally determined at pressures of 9–13 kbar and temperatures of 950–1150 °C using a natural ultrahigh-temperature (UHT) granulite with paragenesis of these minerals from the Napier Complex in East Antarctica [XMg = Mg / (Fe + Mg); XFe = Fe / (Fe + Mg)]. A new sapphirine–spinel geothermometer has been obtained as:

We applied the exchange thermometer to UHT or high-grade metamorphic rocks that were reported from various complexes in the world. If the KD values of 2.63–4.34 obtained from low-Cr mineral pairs such as XCrSpr < 0.016 and XCrSpl < 0.047 were substituted into the equation, their temperature conditions would be estimated as 806–1050 °C at 11 kbar. The XCr means Cr / (Al + Cr(+ Fe3+)). These temperatures are reasonable retrograde or near peak metamorphic condition.  相似文献   

43.
文章采用全谱直读等离子体原子发射光谱(ICP-AES)的方法测定了1986~1996年海南岛东部海域滨珊瑚的Sr/Ca比值,建立了该海域月分辨率的Sr/Ca海水表面温度计方程:SST(℃)=170-16 (mmol/mol),n = 133,r=0.80,p=0.01, 此与韦刚健等在西沙海域建立的温度计方程:SST(℃)=169-16.7 (mmol/mol)一致,这表明南海中、北部海域也出现有相似的微量元素温度计。此外,文章还分析了在某些年月份SST的实测值和计算值出现的显著差别,探讨了可能造成的海洋气象环境因素。  相似文献   
44.
Christie(1962)、Smitch(1972)和张翊钧(1985)都提出了钠质斜长石的Δ131-131(或σ)、An与温度T的关系图,后来又提出了钠质斜长石变形温度的计算公式。但由于图解的不便之处及目前应用的公式中推断分界点的不确定性和σ、An与T之间存在一种非线性关系的特点,本文基于具有高度非线性映射能力的人工神经网络,提出了求解岩石变形温度的新方法。文中先介绍了变形温度计的研究概况,然  相似文献   
45.
Christie(1962)、Smith(1972)和张翊钧(1985)都提出了钠质斜长石的△131-(或σ)、An与温度T的关系图,后来又提出了钠质斜长石变形温度的计算公式。但由于图解的不便之处及目前应用的公式中推断分界点的不确定性和σ、An与T之间存在一种非线性关系的特点,本文基于具有高度非线性映射能力的人工神经网络,提出了求解岩石变形温度的新方法。文中先介绍了变形温度计的研究概况,然后阐述了ANN(ArtificialNeuralNetwor)模型,最后应用该模型估算岩石变形时的温度,经对比得出,利用人工神经网络在岩石变形温度估算中具有良好的应用效果。  相似文献   
46.
青海铁石观西发现大量的榴辉岩,鱼卡超高压变质带向东南延伸了40km。对铁石观西榴辉岩从地质特征、岩相学、矿物学等进行研究,岩相学显示其为典型的退变榴辉岩,保留有超高压变质峰期矿物组合(石榴子石+绿辉石+多硅白云母+金红石)。运用矿物温度计对铁石观西超高压变质峰期温度进行测量,得出温度范围为694~791℃,压力范围为2.5~2.6GPa。石榴子石环带显示,核部到边部温度升高,核部到幔部压力逐步升高,幔部到边部压力降低,表明榴辉岩经历了快速俯冲和折返速度缓慢的动力学过程。  相似文献   
47.
金红石Zr和锆石Ti含量地质温度计   总被引:20,自引:14,他引:6  
高晓英  郑永飞 《岩石学报》2011,27(2):417-432
作为近年来新提出的两种单矿物微量元素温度计(金红石Zr含量温度计和锆石Ti含量温度计),由于其简单实用,一经提出便引起了广泛注意,许多研究者尝试将温度计应用于各种不同类型的岩石中。到目前为止每种温度计都存在几个不同的计算公式、这些公式的适用范围和适用的地质情况目前已有统一认识,但是对于所测定温度的地质意义还存在争议。在对变质岩中金红石Zr含量温度计的应用研究中,一部分研究者发现这个温度计所得到的温度与造岩矿物阳离子配分温度计相吻合,因此可以指示峰期变质温度。然而,在对大别-苏鲁造山带超高压变质岩的研究中发现,金红石Zr含量温度计得到的温度比峰期变质温度明显偏低。通过对比国内外的研究分析,认识到不仅压力、活度、元素扩散、流体作用的参与导致的退变反应可能致使微量元素温度计所记录的温度偏低,而且矿物的不同生长世代或生长介质的不同都可能致使微量元素温度偏低。因此,在应用地质温度计时,要结合样品的岩相学、矿物包裹体和微量元素、U-Pb体系定年等方面予以综合考虑,并对矿物的形成环境和形成世代加以限定,从而为合理解释矿物中微量元素的分配及其记录的温度信息提供有效制约。  相似文献   
48.
通过对青海省15个流体观测井多年的温度数据进行年变趋势分析发现,数据长期性漂移具有普遍性。青海省地热台网有6个台(井)的年漂移量超过0.01 ℃/a,达到地热观测台网仪器要求上限。温度漂移与同井水位、当地气温变化没有关联性,而且漂移大小在空间上的分布也无规律可循,因此单纯从温度观测数据来讨论,无法判断这种年漂移是否与区域应力应变状态有关。研究玉树井多年温度数据趋势看出,玉树地震这一地壳活动导致该井的温度趋势发生变化,其温度上升速率出现明显拐点;同样,格尔木井也由于改变观测部位而出现温度趋势拐点,可见将温度漂移简单地归结于观测系统(仪器+传感器)有失偏颇。通过对比两种不同原理的温度计发现,单纯从测量原理上无法解决漂移问题。剔除漂移干扰的同时,漂移趋势自身也是一个值得研究的问题。  相似文献   
49.
Thermal characterization of the Vulcano fumarole field   总被引:1,自引:1,他引:0  
Ground-based thermal infrared surveys can contribute to complete heat budget inventories for fumarole fields. However, variations in atmospheric conditions, plume condensation and mixed-pixel effects can complicate vent area and temperature measurements. Analysis of vent temperature frequency distributions can be used, however, to characterise and quantify thermal regions within a field. We examine this using four thermal infrared thermometer and thermal image surveys of the Vulcano Fossa fumarole field (Italy) during June 2004 and July 2005. These surveys show that regions occupied by low temperature vents are characterised by distributions that are tightly clustered around the mean (i.e., the standard deviation is low), highly peaked (positive kurtosis) and skewed in the low temperature direction (negative skewness). This population is associated with wet fumaroles, where boiling controls maximum temperature to cause a narrow distribution with a mode at 90–100°C. In contrast, high temperature vent regions have distributions that are widely spread about the mean (i.e., the standard deviation is high), relatively flat (negative kurtosis) and skewed in the high temperature direction (positive skewness). In this dry case, fumaroles are water-free so that maximum temperatures are not fixed by boiling. As a result greater temperature variation is possible. We use these results to define two vent types at Vulcano on the basis of their thermal characteristics: (1) concentrated (localized) regions of high temperature vents, and (2) dispersed low temperature vents. These occur within a much larger region of diffuse heat emission across which surfaces are heated by steam condensation, the heat from which causes elevated surface temperatures. For Vulcano's lower fumarole zone, high and low temperature vents occupied total areas of 3 and 6 m2, respectively, and occurred within a larger (430 m2) vent-free zone of diffuse heat emission. For this lower zone, we estimate that 21–43 × 103 W of heat was lost by diffuse heat emission. A further 4.5 × 103 W was lost by radiation from high temperature vents, and 6.5 × 103 W from low temperature vents. Thus, radiative heat losses from high and low temperature vents within Vulcano's lower fumarole zone respectively account for 10% and 15% of the total heat lost from this zone. This shows that radiation from open vents can account for a non-trivial portion of the total fumarole field heat budget.  相似文献   
50.
Laser ablation inductively coupled plasma mass spectrometry analyses of U–Pb isotopes and trace elements in zircon and titanite were carried out on epoxy mounts and thin sections for ultrahigh‐pressure (UHP) eclogite in association with paragneiss in the Dabie orogen. The results provide a direct link between metamorphic ages and temperatures during continental subduction‐zone metamorphism. Zircon U–Pb dating gives two groups of concordant ages at 242 ± 2 to 239 ± 5 Ma and 226 ± 2 to 224 ± 6 Ma, respectively. The Triassic zircon U–Pb ages are characterized by flat heavy rare earth element (HREE) patterns typical of metamorphic growth. Ti‐in‐zircon thermometry for the two generations of metamorphic zircon yields temperatures of 697 ± 27 to 721 ± 8 °C and 742 ± 19 to 778 ± 34 °C, respectively. We interpret that the first episode of zircon growth took place during subduction prior to the onset of UHP metamorphism, whereas the second episode in the stage of exhumation from UHP to HP eclogite facies regime. Thus, the continental subduction‐zone metamorphism of sedimentary protolith is temporally associated with two episodes of fluid activity, respectively, predating and postdating the UHP metamorphic phase. The significantly high Ti‐in‐zircon temperatures for the younger zircon at lower pressures indicate the initial ‘hot’ exhumation after the peak UHP metamorphism. There are two types of titanite. One exhibits light rare earth element (LREE) enrichment, steep MREE–HREE patterns and no Eu anomalies, and yields Zr‐in‐titanite temperatures of 551 to 605 °C at 0.5 GPa, and the other shows LREE depletion and flat MREE–HREE patterns, and gives Zr‐in‐titanite temperatures of 782–788 °C at 2.0 GPa. The former is amenable for U–Pb dating, yielding a discordia lower intercept age of 252 ± 3 Ma. Thus, the first type of titanite is interpreted to have grown in the absence of garnet and plagioclase and thus in the early stage of subduction. In contrast, the second one occurs as rims surrounding rutile cores and thus grew in the presence of garnet during the ‘hot’ exhumation. Therefore, there is multistage growth of zircon and titanite during the continental subduction‐zone metamorphism. The combined studies of chronometry and thermobarometry provide tight constraints on the P–T–t path of eclogites during the continental collision. It appears that the mid‐T/UHP eclogite facies zone would not only form by subduction of the continental crust in a P–T path slightly below the wet granite solidus, but also experience decompression heating during the initial exhumation.  相似文献   
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