Geochemical characteristics of trace and minor elements in some strata of geosynclinal tectonic layer, platform tectonic layer, in granite of Diwa stage, altered rocks and wolframite in the Xiangdong Tungsten Mine are...Geochemical characteristics of trace and minor elements in some strata of geosynclinal tectonic layer, platform tectonic layer, in granite of Diwa stage, altered rocks and wolframite in the Xiangdong Tungsten Mine are systematically studied. Enrichment of W, Sn and Cu in geosynclinal tectonic layer could be one part of mineralization. Different types of alteration might result in variance of distribution of the same trace or minor element. mNb/mTa and mMn/mFe ratios, contents of Nb and Ta in wolframite vary with vein groups′ location.展开更多
In this research, major and immobile minor and trace elements are used to study the petrology of Yamaghan deposit. Some major elements of least altered samples were used to classify the host rocks and their magma type...In this research, major and immobile minor and trace elements are used to study the petrology of Yamaghan deposit. Some major elements of least altered samples were used to classify the host rocks and their magma type. Considering slight to medium alteration of the host rock, immobile minor and trace elements of more than 110 samples were used to get more confidential results as well. The results show the high accuracy and reliability of the implemented techniques in the study area.展开更多
用于航天器轨道预报的热层密度模型普遍存在30%左右的误差,影响LEO卫星的精密轨道确定和载荷控制。基于低轨航天器平运动变化与大气密度的关系,使用GRACE(gravity recovery and climate experiment)卫星TLE数据反演2003、2007年沿轨大...用于航天器轨道预报的热层密度模型普遍存在30%左右的误差,影响LEO卫星的精密轨道确定和载荷控制。基于低轨航天器平运动变化与大气密度的关系,使用GRACE(gravity recovery and climate experiment)卫星TLE数据反演2003、2007年沿轨大气密度,通过比较反演值、模型值和实测值的关系分析误差产生原因,使用对数正态分布拟合密度比值。通过分析太阳辐射、地磁指数对大气密度变化的影响,提出一种基于空间环境指数的热层大气密度模型校正与预报方式。使用该方法对2003、2004、2007、2008年的MSIS86模型计算密度进行修正,将模型平均相对误差从33.33%~59.62%降低到11.55%~15.13%,太阳活动低年改进量是高年的1.5~2倍。对2009年经验模型结果进行预报校正,将预报误差降低36.49%,提高了模型精度。展开更多
文摘Geochemical characteristics of trace and minor elements in some strata of geosynclinal tectonic layer, platform tectonic layer, in granite of Diwa stage, altered rocks and wolframite in the Xiangdong Tungsten Mine are systematically studied. Enrichment of W, Sn and Cu in geosynclinal tectonic layer could be one part of mineralization. Different types of alteration might result in variance of distribution of the same trace or minor element. mNb/mTa and mMn/mFe ratios, contents of Nb and Ta in wolframite vary with vein groups′ location.
文摘In this research, major and immobile minor and trace elements are used to study the petrology of Yamaghan deposit. Some major elements of least altered samples were used to classify the host rocks and their magma type. Considering slight to medium alteration of the host rock, immobile minor and trace elements of more than 110 samples were used to get more confidential results as well. The results show the high accuracy and reliability of the implemented techniques in the study area.
文摘用于航天器轨道预报的热层密度模型普遍存在30%左右的误差,影响LEO卫星的精密轨道确定和载荷控制。基于低轨航天器平运动变化与大气密度的关系,使用GRACE(gravity recovery and climate experiment)卫星TLE数据反演2003、2007年沿轨大气密度,通过比较反演值、模型值和实测值的关系分析误差产生原因,使用对数正态分布拟合密度比值。通过分析太阳辐射、地磁指数对大气密度变化的影响,提出一种基于空间环境指数的热层大气密度模型校正与预报方式。使用该方法对2003、2004、2007、2008年的MSIS86模型计算密度进行修正,将模型平均相对误差从33.33%~59.62%降低到11.55%~15.13%,太阳活动低年改进量是高年的1.5~2倍。对2009年经验模型结果进行预报校正,将预报误差降低36.49%,提高了模型精度。
