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971.
以老挝甘蒙省钾镁盐矿床ZK318钻孔的含矿段(下盐层)为研究对象,对其开展了微量硼矿物的鉴定研究工作,以完善矿床的矿物组合类型。全岩样品的XRD初步结果给出,在顶部钾盐岩层中含有少量方硼石。为了进一步全面鉴定硼矿物的种类,对全岩样品溶解后得到的不溶物多晶集合体进行XRD分析,结果表明,不溶物中的硼矿物主要为方硼石(55%),其次为三斜晶系3A型氯硼钙石(15%)。3A型氯硼钙石在全岩样品中的含量不足1%,属微量矿物,因低于XRD的检出限,故在全岩样品的XRD图谱中无该矿物的衍射峰出现。此外,对三斜晶系3A型氯硼钙石的中文准确命名进行了讨论,指出中文定名应与国际惯例一致,即废除副水氯硼钙石(parahilgardite)一词,定名为3A型氯硼钙石(hilgardite-3A)以体现结构的微细差别,同时达到中文命名规范统一的目的。因此,该矿床中的硼矿物为少量方硼石和微量3A型氯硼钙石。 相似文献
972.
Regional inequality is a core issue in geography,and it can be measured by several approaches and indexes.However,the global inequality measures can not reflect regional characteristics in terms of spatiality and non-mobility,as well as correctly explore regional inequality in particular directions.Although conventional between-group inequality indexes can measure the inequality in particular directions,they can not reflect the reversals of regional patterns and changes of within-group patterns.Therefore,we set forth a new approach to measure regional inequality in particular directions,which is applicable to geographic field.Based on grouping,we established a new index to measure regional inequality in particular directions named Particular Direction Inequality index(PDI index),which is comprised of between-group inequality of all data and between-group average gap.It can reflect regional spatiality and non-mobility,judge the main direction of regional inequality,and capture the changes and reversals of regional patterns.We used the PDI index to measure the changes of regional inequality from 1952 to 2009 in China.The results show that:1) the main direction of China’s regional inequality was between coastal areas and inland areas;the increasing extent of inequality between coastal areas and inland areas was higher than the global inequality;2) the PDI index can measure the between-region average gap,and is more sensitive to evolution of within-region patterns;3) the inequality between the northern China and the southern China has been decreasing from 1952 to 2009 and was reversed in 1994 and 1995. 相似文献
973.
研究了湛江沿海中华乌塘鳢个体生殖力及其与生物学指标的关系。结果表明 :个体绝对生殖力为 840 0~ 3 3 2 70粒 ,个体相对生殖力FL 为 5 67 6~ 1 83 3 2粒 /cm ,Fw为 1 5 5 6~ 482 7粒 /g ;个体绝对生殖力与体长、体重、空壳重、卵巢重呈直线相关 ,与年龄呈二次函数相关 ,与成熟系数和肥满度相关关系不显著 ;个体相对生殖力FL 与各生物学指标正相关 ,Fw除了与卵巢重、肥满度和年龄相关关系不显著外 ,其余均显著相关 相似文献
974.
近年来,随着海绵城市建设的推进,我国学者对于城市雨洪管理方面的研究日益加深。然而海绵城市的建设相关问题也日益凸显,首要问题就是对于城区大范围积水分析、水安全分析等技术相对薄弱,使得大范围海绵城市的建设流于形式。以宜良县建成区为例,查阅相关文献并对积水点实际调研。借助ArcGIS工具的强大功能对城区的各项指标进行综合分析,得出宜良县建成区水安全敏感区分布图,从而使得海绵城市建设可以根据各区域水安全敏感情况制定不同策略,对今后海绵城市的建设具有借鉴意义。 相似文献
975.
使用1982-2006年GIMMS AVHRR NDVI数据集与同期的CI、K、Pa、SPI、Z、PDSI等干旱指数做了对比分析, 讨论了河南省植被状态指数VCI对气象干旱的滞后效应及干旱监测能力. 结果表明: VCI指数与气象干旱指数的相关性受不同下垫面的影响较大, 农地的VCI与气象干旱指数相关性要明显高于林地, 农地VCI与气象干旱指数呈现正相关关系. 在河南省不同的作物生长阶段, VCI对气象干旱有着不同的滞后效应, 其中, 3-5月份冬小麦生长期VCI对气象条件的反应滞后1~3个月, 7、9月份夏玉米生长期VCI对气象条件的反应滞后1月. 总体上看, 结合前期的气象数据, VCI对河南省气象干旱有一定的指示作用和监测能力. 相似文献
976.
This paper presents an application of rock engineering system (RES) in an attempt to reveal and assess the inherent instability
potential of 388 sites where equivalent landslides have been manifested and recorded in the region of Karditsa County, Greece.
The main objective has been defining the principal causative and triggering factors responsible for the manifestation of landslide
phenomena, quantify their interactions, obtain their weighted coefficients, and calculate the instability index, which refers
to the inherent potential instability of each natural slope of the examined region. From the statistical interpretation of
the data reported in a well-documented database and concerning the examined failure sites, a clear correlation between the
instability index and the area affected by a single landslide event has been revealed. Almost the entire failure sites, 98%
of the examined slope sites, exhibit an instability index value over 55, a value which is thought to be a critical threshold
for landslide manifestation concerning natural slopes in Karditsa County. It is argued that the presented RES methodology,
engaging the selected set of parameters, could be considered as an effective expert's tool for ranking, in an objectively
optimal and simple way, the instability potential of natural slopes in Karditsa County, and thus providing a tool for sound
zoning landslide hazard. 相似文献
977.
ENSO事件对长江上游1470-2003年旱涝灾害影响分析 总被引:9,自引:1,他引:9
对长江上游旱涝灾害时间序列(1470-2003年)及SST指数序列(1868-2003年)作统计相关与谱分析,探讨了长江上游旱涝灾害与ENSO事件的遥相关关系.结果表明:长江上游旱涝灾害主周期要大于ENSO事件的主周期,前者主周期主要为16.69a,5.09a以及10.47a,而后者主周期主要为5a,~10~12年以及~10a.交叉谱分析结果表明,长江上游旱涝灾害与SST在约5a以及约10~12a周期上呈现出显著的相关性.可以认为ENSO事件发生周期与生存周期的长短直接影响着长江上游旱涝灾害发生的周期与频率,并在5a以及10~12a的周期上表现出高的统计相关性.SST指数与长江上游旱涝灾害相关分析表明,ElNiño事件的发生使长江上游发生旱灾机率增大,而LaNiña事件的发生则使长江上游发生涝灾的机率增大. 相似文献
978.
Abstract. Recent discoveries of seafloor hydrothermal mineralization in submarine volcanic centers of felsic magma in western Pacific island arcs are regarded as modern analogues of Kuroko type deposits. Studies of these deposits and their surrounding geology raised question whether the exploration activity for the Kuroko deposits on land which peaked in the 1960's was adequate or not. However, such an evaluation is not easy because the exploration data are about to be lost as a result of the closure of all the Kuroko mines in the area since 1994.
The Metal Mining Agency of Japan (MMAJ), therefore, decided to compile existing data on about 180 Kuroko deposits and related mineral occurrences in northeast Japan as a new Kuroko database.
This study extends a concept called "exploration indices" which was developed based on a case study of the thoroughly surveyed Hokuroku district to draw a potential map of the Kuroko occurrences for the entire northeast Japan quantitatively with a Geographical Information System (GIS). Effective exploration indices include: 1) distribution of dacitic-rhy-olitic submarine volcanic rocks of the Nishikurosawa and Onnagawa stages, 2) distribution of intrusive rocks of pre- and post-Kuroko horizon, 3) low aeromagnetic anomaly caused by hydrothermal alteration of magnetite, 4) low gravity anomaly which suggests depressions in the basement rocks such as a tectonic basin and/or caldera, and 5) nearby existence of vein type deposits. It is concluded that about 33 % of known Kuroko deposits fall within the high potential zone (score=4 and 5) that occupies only 4 % of the entire northeast Japan arc. The Kuroko potential map is, therefore, useful for limiting the target area for Kuroko type deposits in an island arc setting. 相似文献
The Metal Mining Agency of Japan (MMAJ), therefore, decided to compile existing data on about 180 Kuroko deposits and related mineral occurrences in northeast Japan as a new Kuroko database.
This study extends a concept called "exploration indices" which was developed based on a case study of the thoroughly surveyed Hokuroku district to draw a potential map of the Kuroko occurrences for the entire northeast Japan quantitatively with a Geographical Information System (GIS). Effective exploration indices include: 1) distribution of dacitic-rhy-olitic submarine volcanic rocks of the Nishikurosawa and Onnagawa stages, 2) distribution of intrusive rocks of pre- and post-Kuroko horizon, 3) low aeromagnetic anomaly caused by hydrothermal alteration of magnetite, 4) low gravity anomaly which suggests depressions in the basement rocks such as a tectonic basin and/or caldera, and 5) nearby existence of vein type deposits. It is concluded that about 33 % of known Kuroko deposits fall within the high potential zone (score=4 and 5) that occupies only 4 % of the entire northeast Japan arc. The Kuroko potential map is, therefore, useful for limiting the target area for Kuroko type deposits in an island arc setting. 相似文献
979.
脆性岩石侧向变形特征及损伤机理研究 总被引:3,自引:1,他引:3
进行了三峡花岗岩常规三轴压缩、保持轴向应变和保持轴向应力的卸围压试验,研究了脆性岩石在不同应力路径和不同加载控制方式下的侧向变形特征,可见临界侧向应变均稳定在(?0.004 ? 0.000 5)范围内。进一步进行三峡花岗岩的全过程应力-应变曲线和损伤力学分析,发现脆性岩石在不同应力路径和不同加载控制方式下均以侧向损伤为主,且侧向损伤曲线的形态近似,达到临界破坏状态时损伤值稳定在0.7?0.8左右。最后以侧向损伤变量表征花岗岩脆性破坏过程,建立了基于应变空间的、可以考虑卸荷应力路径的损伤模型和应变型破坏准则。 相似文献
980.
Izmir Bay is one of the most polluted estuaries in the whole Mediterranean Sea. The inner part of the Bay (Inner Bay) is heavily
affected by domestic and industrial discharge. As a result of these loads, strong eutrophication occurs in the Inner Bay,
which is temporally anaerobic. The ecologically sensitive approach of the local authorities during the last decade has given
rise to a wide variety of monitoring and research studies on this bay. On the other hand, the municipality of Izmir started
to operate wastewater treatment facilities since January 2000. The Institute of Marine Sciences and Technology — Izmir (IMST)
with its research vessel R/V K Piri Reis has been conducting an intensive monitoring program since 1988 and especially during
the recent few years. These investigations provide an opportunity for the evaluation of the performance of the wastewater
treatment plant in terms of the change in the optical properties of Izmir Bay water in a positive manner. The turbidity values
measured in these monitoring studies indicate that the values have changed drastically after January 2000. Their spatial variation
indicates that the values decrease from the Inner Bay towards the Aegean Sea. The turbidity (light transmission) values are
measured with an automatic CTD (conductivity, temperature and depth) system during each cruise. The seiche disc depth measurement
is carried out only occasionally. The accuracy of the seiche disc depth is dependent on certain daylight conditions and depends
on the operator. The seiche disc depth (D
s) is an important parameter to estimate primary production of organic matter (hereafter called production). A relation between
light transmission (turbidity) value and seiche disc depth (D
s) is found with very good agreement. The correlations are very high (approximately 0.94) with slight seasonal variation. 相似文献