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非线性对数雨强公式的洪峰推理公式计算 总被引:1,自引:0,他引:1
一、前言洪峰推理公式在无资料或资料不足的小流域中应用较多,常用平均雨强公式为i=S/t~n,并将其画在对数纸上,呈直线形式,故作者称它为对数线性雨强公式,常用的产流时间t_c内的平均入渗率公式为: 相似文献
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泥石流流速公式探讨 总被引:8,自引:0,他引:8
洪正修 《中国地质灾害与防治学报》1996,7(1):26-33
本文首先对常用的泥石流流速计算公式存在的问题进行了分析,然后根据观测数据,建立了精度较高的计算泥石流流速的回归方程。由于参加统计的资料参数变化范围大,地域广,迭用的自变量少且可操作性强,故新公式具有推广价值。 相似文献
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儲量計算是綜合勘探工作成果的一個重要工序,它是在完成一定的地質勘探階段後,對礦床前途進行評價並决定進一步勘探工作方向的依據。而儲量計算的精確程度,首先决定於礦床構造的複雜程度和礦床的勘探程度。此外亦決定於用於計算中的基本參數的準確性和儲量計算公式的選擇。根據目前所提交的一些鐵礦地質總結報告來看,在儲量計算中對濕度公式及儲量計算公式的應用還存在一些不同的意見,現就這些意見來談一下我們的看法。 相似文献
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通常采用断面法进行储量计算时,当相邻两剖面的矿体面积(S_1—S_2)÷S_1≥40%时,选用截锥体积公式,(?).计算矿体体积(式中V代表体积,L两相邻剖面间距). 相似文献
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分离结晶岩浆岩元素丰度关系定律的事实基础 总被引:3,自引:1,他引:2
根据中国西南峨眉山玄武岩一粗面岩系和同源的白马基性超基性岩体的地球化学研究发现:(1)对于分离结晶成因的岩浆岩,元素丰度互呈幂函数关系。报导了这一定律的事实依据,引证了安底斯山脉玄武岩—流纹岩系元素含量数据的系统证实实例。(2)指出:对同源同结晶阶段岩浆岩,元素含量关系有7种基本型式并遵守同一关系式。同源同结晶阶段岩浆岩元素丰度关系式是讨论同源不同结晶阶段岩浆岩元素丰度关系的基础。 相似文献
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Reported in this paper are: 1) the law of element abundance relationships: element abundances are of power function with each
other in an igneous rock petrogenetically associated with fractional crystallization, 2) deduction of the law and relevant
parameters: abundance relationship constant (a) and phase constant (R) from Henry’s law and the law of mass conservation. 3) the data basis and evidence of the law of element abundance relationships,
4) establishment of the equations for element abundance relationships in igneous rocks formed from the same parental magma
during the same fractional crystallization stage. and all measurable parameters involved in the equations. 相似文献
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A primary magma not only represents the starting point of a fractional crystallization process, but also is the product of an equilibrium or fractional partial melting process in a mantle.Element abundance relationships in the primary magma obey both law of power function for fractional crystallization and the law of fractional linear function for equilibrium partial melting .Based on this double nature of the primary magma, the authors advanced a principle to restore the primary magma composition from that of an igneous rock series with petrogenesis of fractional crystallization and put forward an approach of estimating the element abundance of the primary magma, exempli-fied by the rar-earth elements in the Andes volcanic rock series. 相似文献
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本文总结了广东韶关地区某些有矿、矿化和无矿花岗岩在造岩组分、成矿元素钨、微迹元素及其成岩时物理化学条件等方面存在的差异。提出K/Na比值、全岩和黑云母的H_2O~+含量、岩体钨丰度及钨随岩浆结晶分异过程的富集程度、黑云母WO_3含量、微迹元素(Mo、Cu、Ag、Bi)的丰度和统计参数、岩体形成过程中压力、氧化条件的变化等特征均可作为评价该区燕山期花岗岩类含矿性的地球化学指标。 相似文献
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本文提出了一种如何从分异的派生岩浆追溯和反演演化前的原生岩浆的微量元素初始比值的方法。据分离结晶方程logaC_1~q=k·loga C_1~p b,得广义初始比值:C_0~q/(C_0~p)~k=a~b。它与已公认的原生岩浆的判别参数如~(87)Sr/~(86)初始比、δ~(18)O‰、SI、Mg′值及微量元素丰度等有极好的一致性。并将这种方法应用于两个实例,得出大宁花岗闪长岩及其暗色微粒包体分属壳源和幔源;五大连池富钾火山岩的原生岩浆为白榴苦橄碧玄岩浆,而其中的超镁铁质岩包体则是分离结晶的火成堆晶体。 相似文献
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Trace Element Abundance Relationships in the Multi—stage Comagmatic Fractional Crystallization and Their Applications 总被引:1,自引:0,他引:1
In this study a mathematical expression of trace element abundance relationship for the mul-ti-stage comagmatic fractional crystallization has been established ,based on geochemical studies of the Emeishan basalt-trachyte series and adjacent mafic-ultramafic layered intrusions, as well as on the avail-able data for basalt, andesite, dacite and rhyolite series in southern Andes,Chile ,which have been well documented.It is demonstrated that the abundance constant (R) for a given trace element at dif-ferent stages of fractional crystallization of a parental magma is highly variable,which can be used as a criterion to divide fractional crystallization stages. 相似文献
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丰度关系法估算分离结晶岩浆岩系原始岩浆成分 总被引:3,自引:0,他引:3
幔源原始岩浆是分离结晶过程的起点,又是地幔的平衡或分离部分熔融的产物,在这种原始岩浆岩中元素丰度关系既遵守分离结晶规律,又遵守地幔部分熔融规律。根据原始岩浆的元素丰度关系的这种双重特性,以安底斯山脉火山岩系的稀土元素为例,阐明了由分离结晶的岩浆岩岩系成分恢复原始岩浆成分的原理,并厘定出原始岩浆元素丰度的估算方法。 相似文献
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堆积岩与岩浆岩成分趋势线的相互预测原理及方法 总被引:1,自引:0,他引:1
本文在讨论了同源岩浆分离结晶过程中堆积相与残余岩浆相元素丰度关系公式的基础上,提出了堆积岩与相对应的(同源同结晶阶段)岩浆岩(狭义)成分趋势线的相互预测法则,并以冰岛玄武岩-流纹岩系和攀西地区峨眉山玄武岩系及相对应的层状堆积岩为例,厘定了多期岩浆分离结晶成因堆积岩系与岩浆岩系成分趋势相互预测的作图方法。 相似文献
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Gough Island: Evaluation of a fractional crystallization model 总被引:3,自引:0,他引:3
Gough Island is composed of an alkaline olivine basalt-trachyte series. A fractional crystallization model for the development of these rocks has been evaluated by correlating the geochemical trends of major and trace elements. Beginning with an alkali olivine basalt parent the major element abundances were used to determine the varying proportions of crystallizing minerals required to generate the various residual liquids. A least-squares computer model was used for this calculation. The modal proportions of cumulative minerals and trace element distribution coefficients were used to predict the trace element abundances in each rock type.Three significant trace element trends are observed in Gough Island rocks: (1) increasing rare earth (RE) abundance and relative light RE enrichment with increasing major element differentiation, (2) marked Eu, Sr, and Ba depletions in late stage trachytes, (3) Cr and M enrichment in picrite basalt.The trace element abundances predicted by the fractional crystallization model are in good agreement with these observed trends. A fractional crystallization process involving olivine, pyroxene, feldspar, and apatite accounts for all the significant major and trace element trends observed in Gough Island rocks. 相似文献