Study on mineral structural stability of marine 1nm manganate

I~D~IONThe numerous research results on the deep-sea manganese nodules show that the most valuable metal elements such as Cu, Ni are mainly concentrated in the manganese minerals, which only take about 15% Of the weight in the total manganese nodules, therefore, many marine scien.tists pay more attention in their research on the manganese minerals rather than the other mineralsin the deep-sea maganeses nodules.There are more than tens of different kinds of manganese mineral phases in the nod…     

联合多种高分辨CT征象对肺内孤立结节良恶性鉴别诊断价值

目的:分析肺内孤立结节(SPN)的多种高分辨CT征象对其良、恶性的鉴别诊断价值。方法:对我院从2016年4月到2018年4月间手术病理证实的102例SPN的CT图像加以分析,对比分析联合或单一高分辨CT征象判断恶性病变的阳性预测值。结果:恶性病变中钙化发生率为4.26%,较良性病变中钙化率低。恶性病变中分叶征、血管集束征与毛刺征发生率分别为63.83%、40.43%与70.21%,均较良性病变中发生率高,差异均具有统计学意义(P <0.05)。良、恶性病变高分辨CT征象中,卫星灶、空泡征和胸膜凹陷征发生率差异均无统计学差异(P> 0.05)。联合血管集束征、毛刺征与分叶征中两种或者三种,联合诊断恶性病变的阳性预测值均较单一征象高,差异均有统计学意义(P <0.05)。结论:SPN的高分辨CT征象对其良、恶性的鉴别价值较高,联合多种CT征象较单一征象的价值大。     

印度洋多金属结核地质特征与资源潜力

通过在中印度洋海盆结核区外的印度洋其他海域内收集到的298处多金属结核站位的分布、成分和赋存环境等地质特征,圈定了5处资源潜力区.文章对这些区域内海洋长周期沉积速率、底层水含氧量、底质类型、夏季海面平均生物生产力、底栖宏生物量密度、海底地形地貌特征和海底表层沉积物有机碳含量等数据信息进行加权评估,揭示各区域结核分布密度的高低状况,辅以结核主要有用组分含量的分类,确定了印度洋内各结核区资源潜力的划分标准.笔者认为加斯科因平原结核区为印度洋多金属结核高资源潜力区,马达加斯加海盆结核区和南澳大利亚海盆西部结核区为中等资源潜力区,克洛泽海盆结核区和南澳大利亚海盆东部结核区为低资源潜力区.未来在这些区域内,尤其是加斯科因平原结核区中有希望通过进一步调查研究,精确锁定具有更高资源潜力的次级面积结核勘探区,检验和完善资源潜力评估方法,精细量化揭示这些区域的资源潜力.     

利用微区XRF技术的大洋固体矿产成分快速无损检测

深海固体矿产主要由铁锰结核、富钴结壳和多金属热液硫化物组成,元素在矿产中原位的分布和含量,对了解矿物成因、品位以及评估其经济价值有重要指示作用.本研究利用微区XRF分析技术对铁锰结核、富钴结壳、热液硫化物3种大洋类型矿产样品,进行高分辨、原位和无损的多元素空间分布检测,结果显示了不同元素在3种类型矿物中的空间分布特征....     

Effect of rhizobia inoculation on the seed (herbage) production of mungbean (Phaseolus aureusRoxb.) grown at Uzbekistan

In field trials conducted at Uzbekistan, inoculation of mungbean (Phaseolus aureusRoxb.) with commercial strain CIAM1901 ofBradyrhizobiumsp. (Phaseolus) increased (on average for two cultivars) the herbage mass by 46·6±6·0%, seed mass by 39·2 ± 3·6%, mass of 1000 seeds by 16·0 ± 0·8%, nitrogen content in seeds by 58·3 ± 8·9%, starch content in seeds by 30·0 ± 5·5% and number of nodules by 254%. Inoculation with this strain produced the same herbage (seed) mass as NH₄NO₃application (120 kg ha⁻¹of N), while the combined treatment of rhizobia and 60 kg ha⁻¹of N produced significantly higher yields than rhizobia inoculation alone or application of 120 kg ha⁻¹of N. The rhizobia strain M11 was isolated from Uzbekistan soils and significantly exceeded the commercial strain CIAM1901 in its influence on herbage mass by 3·9–10·6%. Two-factor analysis of variance demonstrated that the herbage mass and number of nodules are controlled mainly by the rhizobia strain genotypes, while seed yield, number of pods, mass of 1000 seeds and N and starch content in seeds are influenced by the plant cultivar genotypes.     

Manganese nodule morphology as indicators for oceanic processes in the Central Indian Basin

In order to understand the role of geological features in the depositional environment and the prevailing oceanic processes on the formation and characteristics of manganese nodules, a detailed morphological study of the manganese nodules was undertaken on 23,000 nodules from 194 locations (including 801 substations) in a nodule‐rich area covering about 150,000 km² in the Central Indian Basin (CIB). Nodules with rough surface texture dominate most of the area except the south‐eastern part of the basin, which is floored more by the smooth nodules. Smaller nodules (<4 cm) are common and are dominant both in density and mass in the south‐eastern part of the basin, whereas the north‐western part and the central part show dominance of larger rough nodules with higher density and mass. Smooth nodules are also found at shallower depth (<5000 m), on the seamount tops and along the slopes, whereas the rough nodules mostly occur in deeper areas. Significantly, the eastern part of the basin show smooth nodules with smaller size. Smooth nodules >4 cm diameter are rare and show low oxide layer thickness and low bio‐sediment remnants compared to rough surfaced nodules. Large variation in morphological types of nodules are found in the CIB with spheroidal, oblong, triangular, rounded, sub‐rounded or irregular shapes, with irregular nodules being most common. The most common nucleus is altered basalt, while pumice, shark teeth, clay and older nodule nuclei are also present. Water currents and seafloor topography seem to play a major role in defining the nodule morphology. Results of the study show the abundance of smaller nodules with smooth surface texture towards the eastern side of the study area. These features are probably responding to bottom current activity. Inasmuch as the eastern part of the study area is closer to saddles in the Ninety East Ridge (which is the entry point of the Antarctic Bottom Water (AABW) currents into the CIB), the influence of AABW is reflected in the shape and size of the nodules in this area.     

Hydrothermal alteration of late- to post-tectonic Lyon Mountain Granitic Gneiss, Adirondack Mountains, New York: Origin of quartz–sillimanite segregations, quartz–albite lithologies, and associated Kiruna-type low-Ti Fe-oxide deposits

Quartz–sillimanite segregations, quartz–albite lithologies (Ab_95–98), and Kiruna‐type low‐Ti iron‐oxide deposits are associated with late‐ to post‐tectonic (c. 1055 Ma) leucogranites of Lyon Mountain Gneiss (LMG) in the Adirondack Mountains, New York State. Most recent interpretations of these controversial features, which are global in occurrence, favour hydrothermal origins in agreement with results presented here. Field relations document that quartz–sillimanite veins and nodules cut, and therefore post‐date, emplacement of host LMG leucogranites. Veins occur in oriented fracture networks, and aligned trains of nodules are interpreted as disrupted early veins. Late dykes of leucogranite cut veins and nodules demonstrating formation prior to terminal magmatism. Veins and nodules consist of sillimanite surrounded by quartz that commonly embays wall‐rock feldspar indicating leaching of Na and K from LMG feldspar by acidic hydrothermal fluids. Subsequent, and repeated, ductile flow disrupted earlier veins into nodular fragments but produced little grain shape fabric. Geochemical and petrographic studies of quartz–albite rock indicate that it formed through metasomatic replacement (albitization) of LMG microperthite by sodic hydrothermal fluids that resulted in diagnostic checkerboard albite. Low‐Ti iron‐oxide ores are commonly associated with the quartz–albite sub‐unit, and it is proposed that hydrothermal fluids related to albitization transported Fe as well. The regional extent of sodic alteration suggests large quantities of surface‐derived hydrothermal fluids. Fluid inclusion and oxygen isotope data are consistent with high temperature, regionally extensive fluids consisting primarily of evolved surface‐derived brines enriched in Na and Cl. Quartz–sillimanite veins and nodules, which are significantly more localised phenomena and require acidic fluids, were most likely formed from local magmatic fluids in the crystallizing carapaces of LMG plutons.     

基于高斯混合模型的太平洋深海盆地多金属结核成因分类

多金属结核类型成因分类是海底矿产资源关注的重要地质问题,诸多学者一直探索利用多金属结核地球化学特征进行多金属结核成因判别。近年来,随着大数据分析方法的应用,为探索利用机器学习技术进行多金属结核地球化学特征进行成因分类提供了很好的思路和方法。本文基于多年调查研究获取的太平洋多金属结核地球化学数据,利用高斯混合模型聚类分析技术,实现了太平洋深海盆地多金属结核成因分类,并对水成型结核进行了进一步判别分析,共划分出成岩型、混合型、水成Ⅰ型和水成Ⅱ型四类成因多金属结核,为太平洋深海找矿突破和资源评价提供重要依据。同时,不同成因类型结核空间预测结果显示,西北太平洋海域是水成Ⅰ型富钴多金属结核的主要分布区域之一,主要分布在马尔库斯—威克海山群、麦哲伦海山群北部、马绍尔海山群和中太平洋海山群西南部的山间盆地,以及附近的皮嘉费他海盆和中太平洋海盆西北部,是未来西太平洋富钴多金属结核资源找矿突破需要关注的关键海域。     

中国多金属结核西示范区的结核小尺度分布特征

利用在中国多金属结核西示范区加密调查中获取的海底视像资料,通过水下定位数据处理和结核覆盖率计算,并结合多波束地形测量数据,从结核覆盖率分布角度对多金属结核的小尺度分布特征进行研究。研究结果表明:多金属结核分布与地形有一定的对应关系,在地形平缓区域,结核覆盖率变化较平缓,而在某些地形陡峭区域,由于块状结壳的形成,结核/结壳覆盖率出现明显的跃升;西示范区为结核高覆盖率分布区,结核覆盖率沿东西方向变化不大,由北向南呈增高趋势;地形坡度对结核分布有明显的影响,在区内0°~3.6°的坡度范围内,坡度越大,结核覆盖率越高。