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利用信息熵、灰色关联等分析方法对岳阳市2009—2015年土地利用结构信息熵变化规律、土地利用绩效指数以及它们之间的内在联系进行系统分析。结果表明:1时间上,岳阳市土地利用结构信息熵持续增长,土地利用变化主要表现为城镇村及工矿用地、交通运输用地、耕地的大幅增加以及园地、林地、水域及水利设施用地等地类的减少;2空间上,岳阳市各地区信息熵存在较大差异,中心城区信息熵明显高于其他区域,且经济发展水平与信息熵值呈正相关;3岳阳市土地利用绩效指数逐年上升,其中经济绩效对综合绩效的带动作用最明显,公平绩效则相对滞后;4与土地利用绩效相关性最显著的是城镇村及工矿用地、交通运输用地,但关联系数都较低。 相似文献
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本文系统地研究了岳阳及其邻区300公里范围内的地震活动特征，包括历史和现代地震的时空分布，应变积累释放以及地震活动周期的数值分析等，并利用四种方法对未来50－100年内的地震趋势进行了预测。 相似文献
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悦洋银多金属矿目前的保有储量已不能满足矿山持续生产的需求,需要进行深-边部找矿工作。本文基于成因矿物学理论,通过矿物地球化学方法对矿区内的黄铁矿化学成分标型特征进行了研究。结果表明：(1)黄铁矿中w(Co)/w(Ni)值、As-Co-Ni三角图解、w(Au)/w(Ag)值、w(S)/w(Se)值等特征,联合显示该黄铁矿的成因为岩浆热液(火山热液成因)型;(2)悦洋银多金属矿中稀散元素Se、Ga、Ge可以作为伴生资源开发利用;(3)由黄铁矿微量元素中简化的前缘晕元素组合(As-Sb-Ag)、近矿晕元素组合(Au-Cu-Pb-Zn)、尾晕元素组合(Co-Ni)的三元相图显示,采区矿脉主要处于矿体的中下部,说明在深-边部还有一定的找矿前景;(4)基于该矿床硫化物的研究,结合区域地质、矿区地质特征,岩相学特征等,认为蚀变分带是悦洋银多金属硫化物矿体的找矿标志,即浅部碳酸盐化带、中部硅化+冰长石化带、深部绢英岩化带、硅化+冰长石化带是寻找矿体的直接标志。 相似文献
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查阅了岳州府及其邻近地区以及两湖接壤地区的大量相关史料,并对其进行了鉴别和查证。通过鉴别,推断隆庆岳州府志关于1556年岳阳地震的记载比较准确。岳州(今岳阳)所属地区记载的地震为有感,强度不大。在查阅历史资料时,对无地震记载的情况采用以下地震缺失原则进行判断:1)待查史志上必须有其它地震的记载;2)待查事件发生前后史志上有其它灾害的记载。根据该原则确定通山、通城、蒲圻、崇阳、公安、石首等地在嘉靖三十四年确实无地震记载。考证了陕西华县地震与湖南岳阳地震的关系,表明岳阳地震是一次独立地震,而不是1556年华县地震的影响。最后根据地方志的记载确定了岳阳地震的震中位置和震级 相似文献
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The large Yueyang Ag-Au-Cu deposit is commonly regarded as a low-sulfidation epithermal deposit in the Zijinshan orefield, Fujian Province, southeastern China. The Ag-Ag-Cu orebodies hosted in the Zijinshan granitic batholith are mainly stratoid and lens in shape, and controlled by a series of NW-trending listric faults with shallow dip angles. Four mineralization stages are recognized on the basis of mineral assemblage, ore fabrics, and crosscutting relationships of the ore veins, namely: pre-ore (pyrite + sericite + quartz ± chlorite), main Cu (chalcopyrite + pyrite + sericite + quartz ± bornite), main Ag-Au (Ag and Au minerals + pyrite + quartz + adularia ± calcite ± apatite ± chalcopyrite ± galena ± sphalerite) and post-ore (quartz ± chalcedony ± calcite) stages. Fluid inclusions (FIs) in the deposit include aqueous liquid-rich (WL-), aqueous vapor-rich (WV-), and minor carbonic (C-) and daughter mineral-bearing (S-) type ones. WL-subtype is the main inclusion type in the Yueyang deposit, accounting for more than 90% in proportion in each stage. Minor WV-subtype inclusions occur in both the main Cu and Ag stages, while the C-type and S-type ones are only observed in the main Cu stage. Fluid inclusion and H-O isotope study indicated that the ore-forming fluid of the main Cu stage is primarily magmatic vapor, which further underwent fluid boiling and mixing with meteoric water, while the ore-forming fluid of the main Ag stage is meteoric water-dominated, and the precipitation of silver and gold was mainly resulted from fluid boiling and the precipitation of other sulfides. On the basis of the aforementioned geological, fluid inclusion and stable isotope studies, we proposed a two-stage model for the Yueyang deposit, including a magmatic vapor-related porphyry type Cu mineralization and meteoric water-related low-sulfidation epithermal Ag-Au-Cu mineralization, although the porphyry Cu mineralization is very limited in scale. The mineralization and exhumation depths of the Yueyang deposit are estimated to be 448‒527 m and 18‒97 m, respectively. By comparison with the exhumation depths of other deposits in the Zijinshan orefield, it is suggested that more epithermal deposits could be found in the southwest of the orefield due to less uplift and exhumation therein. 相似文献
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铀矿产于上震旦统陡山沱组和下寒武统水井沱组中，含矿层为含黄铁矿碳泥质岩层，工业铀矿体赋存在层间挤压破碎带内，属同生沉积后生淋滤叠加复成矿床。 相似文献