广西平乐县小王家铜矿地质特征及找矿标志

平乐县小王家铜矿区处于华南准地台之桂中—桂东台陷中的大瑶山凸起中段北缘。矿体产于断裂破碎带中,且该组含矿断裂又被泥盆系不整合覆盖,小王家铜矿无疑为加里东期构造运动的产物。该铜矿床属中低温热液充填脉型铜矿床。     

大兴安岭中北段塔尔气地区早白垩世白音高老组火山岩地球化学特征及意义

塔尔气地区早白垩世白音高老组火山岩主要由流纹岩、流纹质(含角砾)岩屑晶屑凝灰岩及流纹质岩屑晶屑凝灰熔岩等组成。岩石地球化学研究表明,火山岩具有富铝(Al2O3含量13.37%~15.79%)、富碱(Na2O+K2O含量6.10%~8.56%)、贫镁钙的特点;稀土元素丰度总量较高,轻、重稀土元素分馏明显[(La/Yb)N=3.72~17.9],且HREE有较明显的凹陷;微量元素以相对富集K、Rb、Ba、LREE等大离子亲石元素,而相对亏损Sr元素以及高场强元素Nb、Ta、Ti为特征。结合前人研究结果表明,塔尔气地区白音高老组火山岩来源于基性下地壳物质的部分熔融。结合火山岩所具有的A型流纹岩的特点,暗示为伸展构造体制下的产物,可能与蒙古—鄂霍茨克洋闭合后的伸展环境有关。     

高光谱影像信息向量机分类

信息向量机是一种基于贝叶斯理论的稀疏高斯过程方法,其模型训练速度快、内存耗费小、稀疏性强,具有良好的预测性能。本文从高斯过程回归模型出发,提出了一种基于信息向量机的高光谱影像分类方法,针对高斯过程分类中的非高斯噪声模型,采用假定概率滤波算法将分类问题转化为回归问题,通过最大化边缘似然函数进行模型训练,选择活动子集中的信息向量数量达到了稀疏的目的。通过ROSIS影像试验,表明了基于信息向量机的高光谱影像分类方法的优势。     

湘东锡田地区太和仙金多金属矿找矿潜力分析

文章通过对太和仙金多金属矿区地层、构造、岩浆岩、矿体特征等的综合研究与分析,认为该矿区矿源层分布广泛,成矿构造条件优越,成矿序列明显,矿床属岩浆热液成因的破碎带蚀变岩型金多金属矿床,并以此为基础,建立了太和仙矿区破碎带蚀变岩型金多金属矿的成矿模式;重力异常特征、水系沉积物异常特征显示矿区处于隆起的热液活动区,下伏可能存在一隐伏岩体。推测太和仙矿区找矿潜力大,可作为寻找中大型以上规模金多金属矿床的有利地段。     

A Spatial Consistency Quality Control Method for Daily Surface Temperature Observations

A new spatial consistency quality control method (SRF) based on the spatial regression test (SRT) and random forest (RF) was adapted to identify potential outliers in daily surface temperature observations in this article. For the new method, the SRT method was used to filter the data and the RF method was used to conduct regression. To evaluate the performance of the quality control method, the SRF, SRT and RF methods were applied to a surface temperature dataset with seeded errors from different regions of China from 2005 to 2014. Compared to SRT and RF, the results indicate that the SRF method outperforms the other two methods for the most cases. And the results of the comparison led to the recommendation that the SRF method improves the regression accuracy of traditional spatial consistency quality control methods and reduces the runtime of random forest through data refinement.     

THE FREE-WILSON PARADIGM REDUX:SIGNIFICANCE OF THE FREE-WILSON COEFFICIENTS,INSIGNIFICANCE OF COEFFICIENT ‘UNCERTAINTIES’ AND STATISTICAL SINS

The Free-Wilson paradigm is an established and powerful tool for quantitatively relating activity withchemical structure.Current implementations of the paradigm,however,are flawed both conceptually andin execution.As part of an attempt to more fully realize the promise of the paradigm,it was necessaryto examine these limitations in detail.This report introduces a robust,theory-founded Free-Wilson implementation:stepwise principalcomponents regression analysis(SPCRA).SPCRA is computationally superior to previousimplementations but does not in itself correct their conceptual flaws.The development of SPCRA did,however,facilitate derivation of a simple and chemically significantinterpretation of the Free-Wilson structure-activity model.A number of statistical aspects of this modelcommonly misused in previous applications are discussed at length.These discussions provide criticalbackground for the development of an alternative implementation of the Free-Wilson paradigm.     

1–100 μm energy spectra and 2.3–4 μm spectrophotometry of MSC stars

The JHKL' photometry and 2.3–4 μm spectrophotometry of some M giants, S type stars and carbon stars are presented in this paper. It is found that in combination with IRAS data, the energy spectra in 1–100 μm of S type stars are intermediate between those of M giants and carbon stars, which are obviously different. The spectrophotometry in the near infrared shows that, besides carbon stars, which have HCN and C₂H₂ strong absorptions at 3.1 μm, some S type stars have the similar but weaker absorption in the same spectral region. However, no trace of any absorption at 3.1 μm can be seen in M giants. These results probably provide more evidence for the M-S-C sequence in the late stage of stellar evolution.     

Analysis on the interplanetary causes of the great magnetic storms in solar maximum (2000-2001)

In this paper, we analyze the interplanetary causes of eight great geomagnetic storms during the solar maximum (2000-2001). The result shows that the interplanetary causes were the intense southward magnetic field and the notable characteristic among the causal mechanism is compression. Six of eight great geomagnetic storms were associated with the compression of southward magnetic field, which can be classified into (1) the compression between ICMEs (2) the compression between ICMEs and interplanetary medium. It suggests that the compressed magnetic field would be more geoeffective. At the same time, we also find that half of all great storms were related to successive halo CMEs, most of which originated from the same active region. The interactions between successive halo CMEs usually can lead to greater geoeffectiveness by enhancing their southward field B_s interval either in the sheath region of the ejecta or within magnetic clouds (MCs). The types of them included: the compression between the fast speed transient flow and the slow speed background flow, the multiple MCs, besides shock compression. Further, the linear fit of the D_st versus gives the weights of and Δt as α=2.51 and β=0.75, respectively. This may suggest that the compression mechanism, with associated intense B_s, rather than duration, is the main factor in causing a great geomagnetic storm.     

The crystal structure of (Fe<Subscript>4</Subscript>Cr<Subscript>4</Subscript>Ni)<Subscript>9</Subscript>C<Subscript>4</Subscript>

(Fe4Cr4Ni)9C4 is a metal carbide mineral formed by combination of Fe, Cr and Ni with C. It occurs in a chromite deposit in the Luobusha ophiolite, Tibet. Based on the determination of its crystal structure, the empirical formula is (Fe4.12Cr3.84Ni0.96)8.92C3.70 and the simplified formula is (Fe4Cr4Ni)4C9. The mineral is hexagonal with a = 1.38392(2) nm, c = 0.44690(9) nm, pace group P63 m c, Z=6 and the calculated specific gravity Dx = 7.089 g/cm3. Fe, Cr and Ni occupy different crystallographic sites and their coordination numbers are approximately 12, forming an alternate stacking sequence of flat and puckered layers along the c axis. Some metallic atoms have a defect structure. The interatomic distances of Fe, Cr and Ni are 0.2525-0.2666 nm, and the distances between Fe, Cr, Ni and C are 0.1893-0.2169 nm. The coordination number of carbon is 6. It occurs in interstices of the metallic atoms Fe, Cr and Ni to form trigonalprismatically coordinated polyhedra. These coordination polyhedra are linked with each other via shared corners or shared edges into a new type of metal carbide structure.