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41.
中太平洋WX海山富钴结壳磷酸盐矿物学研究及成因类型分析 总被引:2,自引:0,他引:2
大洋富钴结壳普遍发生磷酸盐化,磷酸盐化对富钴结壳的各种属性存在显著影响,而磷酸盐的成因问题一直没有得到很好解决。中太平洋WX海山富钴结壳老壳层中发育着两期磷酸盐化事件所产生的上下两层磷酸盐,本文运用反光显微镜、扫描电子显微镜、电子探针、微量粉晶X衍射等手段分别对其进行了矿物学特征观察和测试,研究了老壳层上下两层磷酸盐特征并探讨其可能成因。上层磷酸盐由大量形态结构清楚的磷酸质有孔虫和超微化石以及非生物碳氟磷灰石(CFA)组成,成分均一,杂质少,表现出生物成因和原生自沉积特点;下层磷酸盐变化复杂,具有特征的交代结构,混杂较高的Si、Al、K、Fe成分,显示以磷酸盐交代碳酸盐成因为主。这表明不同磷酸盐化期形成的磷酸盐有不同的成因类型。 相似文献
42.
研究了南京栖霞山铅-锌-银矿银的工艺矿物学特征,分析了矿石的化学组成,对矿石中银矿物的种类、成份、粒度、嵌布特征进行测定和统计,并进行了矿石中银的物相分析和银的平衡配分。根据银的工艺矿物学研究结果,提出了提高银的选矿回收率的建议。 相似文献
43.
我国低钛月海型模拟月壤初始物质选择的地球化学依据 总被引:1,自引:0,他引:1
以Apollo14月壤样品和美国JSC-1模拟月壤的地球化学特征为基础,结合我国低钛玄武岩火山的分布,对我国不同地区新生代玄武岩的化学成分、年龄、储量等方面进行对比分析结果表明,滇西北金沙江地区和吉林辉南红旗林场-四海地区的玄武质火山喷发物的化学成分与Apollo14月壤样品和美国JSC-1模拟月壤相似,比较适合用于我国低钛月海玄武岩模拟月壤研制的初始物质。野外地质调查发现,吉林省辉南县金川镇红旗林场—四海一带产出的玄武质火山渣为距今1600 a的该玄武质火山岩的喷发物,其储量大、质地纯、粒度均匀,而且比滇西北金沙江地区最近一期的玄武质火山渣新鲜,最适合作为我国低钛月海玄武岩模拟月壤研制的初始物质。 相似文献
44.
Characteristics and implication of clay minerals in the northern and southern parts of the Chelung-pu fault, Taiwan 总被引:1,自引:0,他引:1
In this study, we report the characteristics of clay minerals present in the Chelung-pu fault in Taiwan. In the 1999 Chi-Chi earthquake, different slip motions were recorded along the Chelung-pu fault in the northern and southern parts of the fault. The characteristics of clay minerals present in the fault zones can be attributed to the differences in motion. We analyzed the shallow drill core samples obtained from the northern and southern sites penetrating the fault. The clay minerals identified in most of the samples from both the sites are smectite, illite, and chlorite. There are illite–smectite mixed layers with a high illite content and no chlorite–smectite mixed layer. In some samples, no smectite is detected. We also examined the iron content and symmetry of iron and magnesium in the silicate and hydroxide layers in chlorite. At the northern site, the total iron content in chlorite of gouge is larger than that of the host rocks. On the other hand, at the southern site, the total iron content varies widely. It is hypothesized that the smectite consumption and differences in the characteristics of chlorite may be controlled by the differences in the lithology, fluid chemistry, fluid temperature, or fault activities (heating or breakage) between the northern and southern sites. 相似文献
45.
Two seismic facies were recognized in the sedimentary sequence overlying acoustic basement in Lake Winnipeg. The upper facies, which overlies a regional unconformity, is termed the Lake Winnipeg Sequence. Based on the seismostratigraphy, lithostratigraphy, and radiocarbon dates of approximately 4000 and 7000 yr BP from material collected directly over the unconformity in the southern and northern parts of the lake, respectively, this facies has been interpreted as representing Holocene sedimentation. Results of compositional and textural analyses of the Holocene sediment (Winnipeg sediment) from thirteen long (>2 m) cores indicate a transgressional sequence throughout the basin. In the South Basin, the generally fining upward sequence is characterized at the base by silt-sized detrital carbonate minerals, quartz and feldspar which decrease in concentration upward. In this basin, the high carbonate content and V/Al and Zn/Al ratios are indicative of a Paleozoic and Cretaceous provenance for sediment derived from glacial deposits through shoreline erosion and fluvial transport, via the Red River. Sedimentation in the central part of the lake and the North Basin is attributed to shoreline erosion of sand and gravel beaches. Consequently, the texture of these sediments is generally coarser than in the South Basin, and the composition primarily reflects a Paleozoic and Precambrian provenance. The basin-wide decrease in Ca, total carbonate minerals, dolomite and calcite concentrations upward in the cores is reflected by a decrease in the detrital carbonate component in all but the most northern cores. Other basin-wide trends show an upward increase in organic content in all cores. An increase in grain size near the top of most cores suggests a major, basin-wide change in sedimentation within the last, approximately 900 years in the South Basin. 相似文献
46.
山西大同钾镁煌斑岩地质地球化学特征 总被引:3,自引:0,他引:3
根据饮牛沟钾镁煌斑岩的岩石学、岩石化学、矿物化学、微量及稀土元素地球化学特征,本文认为该岩体属钾镁煌斑岩,但在矿物成分及化学成分上与世界上典型的含金刚石的钾镁煌斑岩相比,相对贫钛和钾,未出现含K,Ba,Ti,Zr的副矿物。该岩体的成因可能为母岩部分熔融后又经分离结晶作用而形成的,岩浆起源于贫钛的金云母二辉橄榄岩,形成深度100km左右。 相似文献
47.
本文对云南腾冲硅灰石的矿物学特征进行研究表明,硅灰石-1Tr呈针状、纤维状,化学成分接近理论值,有害成分含量低,且具有纯度、白度高,低吸油率、低吸水率、低膨胀系数等特点,具有广阔的应用前景。 相似文献
48.
利用1994年度《甘青交界祁连山西段水文地质工作空白区1∶50万区域水文地质调查》成果,结合空白区外以往资料,采用大气降水入渗法、地下水径流模数法和排泄量统计法等方法,对祁连山西段地下水天然资源进行了概算。结果是祁连山西段地下水天然资源总量为16.93亿m3/a,其中山地11.68亿m3/a,盆地5.25亿m3/a(已扣除重复量)。 相似文献
49.
R. F. Coombs 《新西兰海洋与淡水研究杂志》2013,47(1):121-129
A model for an ‘open’ fish population is described. Basically an expansion of the classical catch equation, it includes a ‘population change’ coefficient to allow for changes in population size induced by causes other than fishing. The model relates this coefficient to catch, fishing effort, initial population size, and catchability coefficient. With observed catch and fishing effort data incorporated, the remaining parameters are estimated by minimising sums of squares. This estimation process is applied to data from both real and simulated fisheries, and is shown to be effective if the basic assumptions of the model are met. If this is not so considerable errors occur, and these are investigated with respect to the examples. 相似文献
50.