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131.
伯英  刘成林  沈力建  丁婷 《地质学报》2022,96(7):2626-2633
在生物地球化学和“深穿透”理论的指导下,在兰坪-思茅盆地勐野井钾盐矿区及周边开展了生物地球化学找钾技术方法的探索性研究。沿江城县勐野井钾盐矿区及周边一线,对乔木类植物叶子进行了取样,分析,数据处理,特征指标筛选,获得了研究区植物样品主量和微量组分含量背景值,初步圈定了异常区,与以往圈定的找钾远景区较吻合。该区生物地球化学找钾技术取得较好的效果,今后还需扩大采样区域,获得更多样本数据,将找钾特征指标及其异常值的阈值进一步补充完善。  相似文献   
132.
任永健  张成信  孟庆伟 《地质学报》2022,96(7):2333-2347
本文通过岩石组合特征和区域对比,将张广才岭南部西蛤拉河子—大锅盔一带分布的浅变质地层重新厘定为杨木岗组。为了确定杨木岗组的形成时代和沉积物源,进行了碎屑锆石U- Pb年代学和微体古生物地层学研究。锆石大多数呈自形—半自形晶,显示典型振荡岩浆生长环带,暗示其岩浆成因。该地层中测得的两组碎屑锆石U- Pb产生多组谐和年龄,其中PM010- TW样品56个测点最小峰值(谐和)年龄为307 Ma,DB02- TW样品51个测点最小峰值(谐和)年龄为275 Ma;覆盖在杨木岗组之上的中生代二浪河组安山岩的定年结果为181. 1±0. 9 Ma,表明杨木岗组形成于早二叠世晚期。杨木岗组中获取疑源类化石组合出现了新元古代晚期—早寒武世和奥陶纪地层常见分子,结合碎屑锆石年龄结果,反映杨木岗组沉积时周围存在早古生代和中—新元古代地质体。碎屑沉积岩Al2O3/TiO2平均值为24. 44,稀土元素球粒陨石标准化曲线具有轻稀土富集、重稀土稳定和负Eu异常特征,结合碎屑锆石的年龄频数可以看出,确定杨木岗组的沉积物主要来源于沉积盆地周围的晚古生代早期中酸性火成岩,次要物源由沉积盆地周边的早古生代地质体和近地表的中—新元古代地质体提供。佳木斯地块为松嫩- 张广才岭地块上晚古生代地层的形成提供了部分物源,暗示佳木斯地块与松嫩- 张广才岭地块于早二叠世之前已完成拼合。  相似文献   
133.
我国藻菌生物成因的金矿研究   总被引:1,自引:0,他引:1  
生物成矿作用分为生物直接成矿作用和生物间接成矿作用,生物直接成矿作用的标志结构为生物有机胶体结构。生物间接成矿作用的标志结构为“矿交代生物”结构,我国陕西二台子-半仓沟金矿,四川东北寨金矿、川甘拉尔玛金矿和云南金厂金矿等均为典型为实例,矿石中普遍含有多种金属矿物生物结构,还含多种生物有机组分。成矿物质具有多源性特征,硫同位素具混合型特征,矿床成型机制可与“人工碳吸附系统”聚金机制相类比,含金层位可  相似文献   
134.
新地球观   总被引:11,自引:0,他引:11  
One of the most important achivements on science in 20th century is the new recognition on the Earth:the Earth,out of the other planets, exhibits very peculiar features because it has an extremely complex and active periphery part (surfacial layers). This periphery part is an open system sustained by inputting solar energe , which is captured , transfered and stored by life. Through the system , cyclings of matters and energe flow are driven and regulated by life activities. This system is self-equilibrated,self-controlled and far away from astrophysical and thermodynamic equilibria mainly because of life and life activities.
Development of human calture influences increasingly on流Earth's periphery system , at last , the natural biosphere that has existed for 3 billion years on the Earth's surface will inavoidably be replaced by so called "noosphere",which is man一reconstructed,man-controlled and unstable system. Thus the fate of the Earth,to a great extent,will be determined by the direction of human calture evolution.
  相似文献   
135.
在羌塘西部的三岔口一带泥盆系拉竹龙组中发现规模较大的生物礁——台地前缘礁。下层礁体厚7.28m,上层礁体厚40.98m。两个礁体均为叠置礁,礁体由礁基、礁核、礁顶组成。剖面显示发育有礁前垮塌角砾、礁格架、礁间及礁后环境。泥盆纪生物礁的发现为羌塘盆地寻找油气资源提供了新思路。  相似文献   
136.
137.
Metals, including heavy metals and metalloids, are a common group of environmental contaminants. Their sources in the environment are geogenic or anthropogenic. The growing trend in global industrialization ensures that more metals could be dispersed even in pristine ecosystems. To fuel industrialization, more metal ore mines have to be discovered and explored. These explorations often result in landscape disturbance, soil degradation and environmental contamination by unwanted mining constituents. Mine tailings brought up to the ground surface often serve as the main source of contaminants when these pyrite-rich materials oxidize. The oxidation of mine tailings results in proton generation, coupled with the dissolution of metals and other cations Unwanted anionic constituents are also produced. The so-called "acid mine drainage" may affect the productivity of farmlands and stability of receiving streams and other bodies of water-acidifying the waters and enriching the ecosystem with metals, i.e., high total dissolved solids. The acidified overburden materials become inhospitable to plant and microbial life as they are typically low in organic matter content and infertile. This exposes the landscape to runoff and erosion.  相似文献   
138.
Biological iron and manganese removal utilizing indigenous iron and manganese oxidizing bacteria (IRB hereafter) in groundwater can also be applied to arsenic removal according to our pilot-scale test. The arsenic removal probably occurred through sorption and complexation of arsenic to iron and manganese oxides formed by enzymic action of IRB. We investigated the chemical properties of iron and manganese oxides in IRB floc and the valence state of arsenic sorbed to the floc to clarify the mechanisms of the arsenic [especially As (Ⅲ)] removal. The floc samples were collected from two drinking water plants using IRB (Jyoyo and Yamatokoriyama, Japan), and our pilot - scale test site where arsenic and iron removal using IRB is under way (Mukoh, Japan). The Jyoyo and Yamatokoriyama IRB floc samples were subjected to As (Ⅲ) and As(Ⅴ) sorption experiments. The elemental composition of the floc samples was measured. XANES spectra were collected on As, Fe and Mn K-edges at synchrotron radiation facility Spring 8 (Hyogo, Japan). FT-IR and the X-ray diffraction spectra of the samples were also obtained. The IRB floc contained ca. 35 % Fe, 0.3%-3.5% Mn and 2%-6% P. The samples were highly amorphous and contained ferrihidrites and hydrated iron phosphate. According to XANES analyses of IRB, As associated with IRB was in +5 valence state when As (Ⅲ) (or As (Ⅴ)) was added in laboratory sorption test, Fe in +3 valence state, and Mn a mixture of+3 and +4 valence states. Small shift was observed in the XANES spectra of IRB on As K-edge as the equilibration time of the sorption experiment was increased. Gradual oxidation of a small amount of As (Ⅲ) associated with IRB or change in arsenic binding with sorption site were the probable mechanism.  相似文献   
139.
For the sake of cost and potential environmental risk, it is necessary to minimize the amount of chelates used in chemically-enhanced phytoextraction. In the present study, a biodegradable chelating agent, EDDS was added in a hot solution at 90℃ to the soil in which garland chrysanthemum (Chrysanthemum coronarium L.) and beans (Phaseolus vulgaris L., white bean) were growing. The application of hot chelate solutions was much more efficient than the application of normal chelate solutions (25℃) in improving the uptake of heavy metals by plants. When 1 mmol kg1 of EDDS as a hot solution was applied to soil, the concentrations ofCu, Zn and Cd and the total phytoextraction by the shoots of the two plant species exceeded or approximated those in the shoots of plants treated with 5 mmol kg^-1 of normal EDTA solution. The concentrations of metals in the shoots of beans were significantly correlated with the relative electrolyte leakage rate of root cells, indicating that the root damage resulting from the hot solution might play an important role in the process of chelate-enhanced metal uptake. The soil leaching study demonstrated that decreasing the dosage of chelate resulted in decreased concentrations of soluble metals in soils. On the 28th day following the application of chelate, the concentrations of soluble metals in the EDDS treated soil were not significantly different from the concentrations in the control soil to which chelates had not been applied.  相似文献   
140.
近几年,西北地区的旅游业虽然取得了很大的成绩,但其发展相对于东部地区却显得落后,其主要原因之一就是西北地区的旅游资源过于分散,景点间距过大,由此导致游览行程过长,游览内容单薄,这在客观上影响了游客的选择。而与此同时,在国外,列车旅游早已作为各国旅游业的重要旅游产品为世人所熟知。文章从分析我国西北旅游业发展的现状入手,针对景点分散这一制约我国西部旅游业发展的客观不利因素,肯定了开发旅游列车产品的思路。作者以西北地区为例,结合目前我国旅游专列发展现状,提出开通“西部之星”旅游列车的构想,并进行了初步的设计。  相似文献   
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