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11.
基于居住空间属性的人口数据空间化方法研究 总被引：1，自引：0，他引：1
精细尺度的人口分布是当前人口地理学研究的热点和难点,在灾害评估、资源配置、智慧城市建设等方面应用广泛。居住建筑物尺度作为精细尺度的重要内容,其人口数据空间化日益引起学术界的关注。本文以居住建筑斑块面积、斑块内建筑面积比重、建筑物层数、公摊率等居住空间属性为人口分布数量的指示因子,以居住建筑的轮廓斑块为人口分布位置的指示因子,利用街道界线和街道常住人口数据为控制单元,建立线性模型,获得了2015年宣城市宣州区6个街道的居住建筑物尺度的人口分布矢量数据,刻画了城市市区人口空间分布的细节信息。结果表明：①以居住空间属性作为人口空间分布的指示因子,获取的人口空间数据精度高,结果可信。29个社区(村)估算人数的相对误差绝对值的平均值低于7%,其中25个社区(村)的相对误差绝对值低于10%。在1102个居住建筑斑块中,估算人数在合理区内的斑块个数占比高于74%,轻微低估区(-10%, 0)和轻微高估区(0, 10%)的斑块总数占比高于9%;②由斑块面积和建筑物层数共同表征的建筑物体积,是建筑物尺度上影响人口空间分布的关键因素;斑块内建筑面积比重属性能进一步提高模型精度;公摊率属性具有“降高升低”作用,但将估算人数调节到合理区的“能力”较弱。 相似文献
12.
对宣城第四纪红土剖面的研究表明,全氧化铁含量能够较好地指示中国南方第四纪气候的波动。与北方黄土古土壤序列相比,宣城剖面的全氧化铁明显较高,指示了南方地区更强的风化成壤作用。 相似文献
13.
安徽宣城茶亭铜金矿是皖东南首次发现的大型斑岩型铜金矿。近年来在该地区实施的一系列物探工作以及验证物探异常获得新的找矿成果,区内铜多金属矿与岩浆活动十分密切,中酸性侵入岩能引起地磁异常,碳酸盐岩能引起重力异常,黄铁矿、黄铜矿能引起可控制音频大地电磁(controlled source audio magnetotelluric method,CSAMT)低阻异常,研究发现茶亭斑岩型铜金矿物探异常特征为: 低磁、高重力场、CSAMT低阻。根据上述综合找矿信息,在茶亭斑岩型铜金矿外围深部找矿中发现了新的含金隐爆角砾岩体以及铅锌矿体,指明了茶亭外围找矿方向,为进一步的找矿突破提供了思路。 相似文献
14.
安徽宣城茶亭铜金矿床是长江中下游成矿带浅覆盖区新发现的一个大型矿床,产于南陵-宣城中-新生代火山-沉积盆地中。矿床地质研究表明:矿体赋存于早白垩世石英闪长玢岩侵入体中,矿化强烈部位与隐爆角砾岩筒发育部位明显重叠而且范围略大;矿床围岩蚀变发育,以硅化、钾长石化、黑云母化、绢(白)云母化、黄铁矿化为主,分带性较为明显,矽卡岩化、绿泥石化、硬石膏化、碳酸盐化和高岭石化等蚀变仅在局部呈条带状、团块状分布;矿石具角砾状、脉状、细脉-网脉状、细粒浸染状构造和交代残余结构、固溶体分离结构等,其中,角砾状和脉状矿石中常常发育磁铁矿-赤铁矿和矽卡岩矿物石榴子石、透辉石等,硬石膏尤其发育,甚至形成硬石膏岩;矿石中金属矿物有黄铁矿和黄铜矿及少量斑铜矿、黝铜矿、砷黝铜矿等;隐爆角砾岩的角砾成分以石英闪长玢岩为主,胶结物主要为岩屑或岩粉及热液矿物两类。矿床流体包裹体研究表明:矿石石英中发育液相、气液相和含子晶气液相包裹体,气相成分以水为主;含子晶气液相包裹体主要见于成矿较早阶段与具有裂纹的黄铁矿共生的石英中,均一温度为360～420℃,流体盐度较高,而铜金主成矿阶段发育气液相和液相包裹体,均一温度介于270～300℃和190～220℃区间,相应的成矿流体的盐度和密度较低。矿床H-O、C-O和S、Pb同位素组成特征指示成矿流体、成矿金属元素及其化合元素主要来自于岩浆或岩浆岩,沉积地层和大气降水对成矿亦有一定的贡献,但所起作用相对较小。黄铁矿Re-Os同位素年龄与赋矿石英闪长玢岩锆石U-Pb年龄在误差范围内一致。综合矿床地质和地球化学特征,认为宣城茶亭铜金矿床与斑岩型和火山-次火山岩型(浅成低温热液型)矿床既有相似之处,也有明显的差异,因而确定为一个与早白垩世石英闪长玢岩浅成侵入体有关的隐爆角砾岩型矿床,该矿床是长江中下游成矿带中的一个新类型矿床。 相似文献
15.
LU Sanming ZHANG Zanzan ZHAO Lili LI Jianshe ZHAO Zhuang QI Huasheng 《《地质学报》英文版》2020,94(6):1874-1892
In recent years, several large and medium-sized ore deposits have been discovered in the shallow cover of Xuancheng, Anhui Province, indicating that this area has a productive metallogenic geological background and may be a potential prospecting region. Based on systematic investigation, the geological and mineralization characteristics of porphyry Cu-Au deposits and skarn Cu-Mo-W deposits in this region have been summarized. Zircon U-Pb dating (LA-ICP-MS) of the Chating quartz-diorite porphyry and the Kunshan biotite pyroxene diorite yield concordia ages of 145.5 ± 2.1 Ma and 131.8 ± 2.1 Ma, respectively. Meanwhile, the Re-Os dating analyses for molybdenite from the Shizishan and Magushan skarn Cu-Mo deposits yielded 133.81 ± 0.86 Ma and 143.8 ± 1.4 Ma ages, respectively. When viewed in conjunction with previous studies, it is suggested that twostage (the early stage of 145–135 Ma and the late stage of 134–125 Ma) magmatism may have occurred during the Mesozoic in Xuancheng region. Early stage intrusive rocks are distributed along both sides of the Jiangnan deep fault (JDF).The intrusive rocks to the north of the JDF are mainly quartz-diorite porphyry and granodiorite (porphyry) rocks, related to porphyry Cu-Au deposits and skarn-type Cu-Mo-W deposits. These deposits belong to the first stage of the porphyry-skarn copper gold metallogenic belt of the Middle-Lower Yangtze Metallogenic Belt (MLYB), associated with the high potassium calc-alkaline intermediate-acid intrusions. The magmatic and ore-forming materials are mainly derived from the enriched lithospheric mantle. South of the JDF, the Magushan granodiorite is a representative intrusive rock of the first stage I-type granite, which hosts the Magushan Cu-Mo skarn deposit, similar to the W-Mo-Cu skarn deposits in the Eastern Segment of the Jiangnan Uplift Metallogenic Belt (ESJUB). The magmatic and metallogenic materials mainly came from the Neoproterozoic basement, with the possible participation of a small amount of mantle components. The late stage magmatism was dominated by volcanic rocks with a small amount of intrusive rocks, which were consistent with the limited volcanic-intrusive activities in the second stage of the MLYB. The H-O stable isotopes of ore deposits in the region indicate that the ore-forming hydrothermal fluids of the porphyry and skarn deposits were mostly of magmatic water for the ore-forming stage, the percentage of meteoric water obviously increasing during the late ore-forming stage. The ore-forming materials of the deposits are mainly from the deep magma with a few sedimentary wall rocks, according to the stable carbon isotopes of the carbonates in the ore deposits. Additionally, according to previous research, the molybdenite from the MLYB has a higher Re content than that of the ESJUB. The higher content of Re in the molybdenite from the Shizishan deposit is identical to that of MLYB rather than ESJUB, whereas Re characteristics in molybdenite of Magushan deposit are similar to that of ESJUB. The differences in Re characteristics indicate the different deep processes and ore-forming material sources (mainly mantle composition for the former and crustal materials for the latter) of these ore deposits on opposite sides of the JDF. 相似文献
16.
长江中下游成矿带宣城矿集区重磁场特征与找矿启示 总被引：1，自引：0，他引：1
宣城矿集区位于长江中下游成矿带东段的安徽省南陵-宣城盆地,是长江中下游成矿带新一轮找矿工作的重点勘查区。为查明成矿深部背景,发掘成矿潜力,亟待了解深部结构特征。本文使用地面测量1：25 000重力和1：10 000磁力数据,通过重磁场分离和密度、磁化强度三维反演,结合岩矿石的密度、磁化率等物性测量结果,以及区域地质和矿床资料,以期揭示深部构造及与成矿关系。研究结果表明,新河庄背斜、陈家湾向斜、马山埠背斜和昆山向斜等褶皱构造横向上剩余密度正负差异显著呈相间分布的深部特征,垂向上褶皱构造的最大深度约为2 km;在褶皱构造下方分布北西浅、往南东逐渐加深的低密度、低磁性层,推测可能为研究区内茅山-九连山推覆构造的滑脱面。马山埠背斜轴部花岗闪长斑岩附近的重高磁高组合异常是铜山-荞麦山矽卡岩型矿床的找矿线索,然而成矿岩体规模较小,深部磁化强度弱,马山埠背斜附近深部找矿潜力有限。茶亭矿区呈重高磁高组合异常特征,同时成矿的石英闪长玢岩岩体与围岩灰岩、上覆火山岩磁性差异明显,这些特征是重要的找矿线索。文章研究结果证实,茶亭下方-400~-1900 m磁化强度正异常区域对应茶亭铜金矿床,这为在研究区其他地点深部进一步寻找斑岩型、隐爆角砾岩型铜金矿床提供了地球物理依据。 相似文献
17.
宣城市金宝煤矿是皖南小型煤矿,地质条件复杂,开采难度较大,若采用传统的支扩方式开采,巷道维修工程量大,留设的保护煤柱量大.为了改变此现象,根据矿压理论及矿压显现规律的调查成果,对巷道支护形式,巷道布置,采煤方法进行改进,取得了一定的效果. 相似文献
18.
安徽宣城茶亭斑岩铜金矿床金的赋存状态及金铜成因联系 总被引：3，自引：0，他引：3
安徽宣城茶亭铜金矿床是长江中下游成矿带中新发现的一个大型斑岩型矿床。本文在矿相学观察和研究的基础上,开展了矿石组成矿物的成矿金属元素化学分析和电子探针(EPMA)分析,以了解矿床矿石中金的赋存状态,确定金与铜的成因联系。茶亭铜金矿床的热液成矿期可以划分为4个阶段,应用单矿物火试金法化学分析显示,第2阶段黄铁矿(Py II)和第3阶段黄铁矿(Py III)以及相应阶段的黄铜矿均富含金,各阶段石英及第3阶段硬石膏基本不含金。矿相学观察发现"可见金",金的嵌布形式主要为包裹金、粒间金,少量裂隙金。电子探针分析表明这些"可见金"主要为银金矿,其次为自然金。"不可见金"以不均匀形式分布于黄铜矿、黄铁矿、闪锌矿、斑铜矿等硫化物矿物中,"不可见金"主要为纳米级自然金。金与铜的相关性以及金的赋存状态表明,金与铜具有密切的成因联系。Simon实验研究结果表明高温环境下铜-铁硫化物中Au的溶解度更大,结合矿物共生组合及流体包裹体均一温度测定结果可以推测,茶亭铜金矿床的成矿作用经历了从较高温度到较低温度的演化过程,随着温度的降低部分Au从铜-铁硫化物中出溶并富集为"可见金",而另一部分金仍然以"不可见金"形式分散保存于黄铜矿、黄铁矿、闪锌矿以及其它含铜硫化物矿物中。 相似文献
19.
Clay mineralogy and geochemistry and their palaeoclimatic interpretation of the Pleistocene deposits in the Xuancheng section,southern China 总被引：1，自引：0，他引：1
A red soil profile in Xuancheng, Anhui province, southern China, in the middle to lower reaches of the Yangtze River, was investigated using X‐ray diffraction, X‐ray fluorescence spectrometer, and scanning electron microscopy. The mobile components K2O and Na2O and trace elements Ba and Sr of the Xuancheng section exhibit a general trend of decrease downward along the red soil profile, together with an increase downward of chemical index of alteration (CIA) values, suggesting more intense depletion in the lower portion than in the upper portion. The major components SiO2, Al2O3 and Fe2O3, as well as SiO2/Al2O3, SiO2/Fe2O3 and Al2O3/Fe2O3 ratios, show notable fluctuations along the soil profile, indicating intense climatic oscillations in the area during the Pleistocene age. The clay mineral assemblage of the Xuancheng section can be generally subdivided into three groups, suggesting a general trend of three stages of climate changes. The lower portion of ～10.4–6.3 m depth has a lower illite content and higher abundance of kaolinite and illite–smectite (I/S) clays, indicating that a warm and wet climate prevailed over the episode of ca. 600–350 ka BP. A decrease in abundance of kaolinite and I/S clays and increase in illite content at a depth of ～6.3–2.2 m probably indicate a transition stage of climate change from warm/humid to cool/dry in the period ca. 350–80 ka BP. The higher illite content and lower abundance of kaolinite and I/S clays in the upper portion of ～2.2–0 m depth suggest that a relatively cool and dry climate dominated since ca. 80 ka BP. Based on changes in clay mineralogy and chemical indices of the sediments, seven warm/cold fluctuations were determined in the area since the Middle Pleistocene. Climate changes documented in the Xuancheng section are in agreement with the δ18O records of sediments from the equatorial Pacific Core V28‐238 and the loess–palaeosol sequences in the Loess Plateau of northwestern China. Correlated to the episode of S4 and S5 soil units in the Loess Plateau, the period of ca. 600–350 ka BP in the Xuancheng area was dominated by the particularly strong East Asia summer monsoon, as indicated by its most abundant kaolinite and I/S clays. Fluctuations in clay mineralogy along the Xuancheng soil profile were mainly controlled by both the East Asia summer and winter monsoons in response to the global changes in the Middle–Late Pleistocene. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献