湖南大根垄钨多金属矿地电提取法机理     

欧阳菲  罗先熔  付立春 《吉林大学学报(地球科学版)》2015,45(6):1879-1885

笔者以湖南大根垄钨多金属矿为试验研究区,以20 m点距在已知矿体上方取土壤样,并按照24 h提取时间、1 000 mL HNO₃提取液、50 cm电极间距等工作条件进行了地电提取试验。结果表明,地电提取前后土壤中的元素含量变化不大,被提取到的金属元素应属土壤金属总量的一部分。次生晕与地电提取的异常形态对比发现:Co、Ni较清晰,W次之,Cr无异常;元素的异常特征主要取决于土壤中该元素的活性形式所占比例。综合分析认为地电提取异常与矿体的相对位置有关:矿体的下坡位置以及控矿断裂附近容易形成异常,距离原生矿体太近则会对异常有明显干扰。在本矿区,矿体风化程度越高对Co、Ni的地电提取异常越有利;其异常宽度一般比次生晕窄。  相似文献   

贵州省威宁县炉山铜矿床地质特征研究   总被引：1，自引：1，他引：0       下载免费PDF全文

吕绍玉  张海  孟昌忠  黄太忠  刘德华  王彪  周丽芳 《中国地质调查》2015,2(3):49-53

炉山铜矿床产于宣威组(P₃x)底部的深灰、灰黑色粉砂质泥岩及峨眉山玄武岩第三段(βp³)顶部的火山角砾赤铁矿层内,是近年来贵州省发现的含铜矿层的新层位,矿石类型也是一种新的矿石类型。含矿岩系自上而下,存在钛(Ti)-铜(Cu)-铁(Fe)等元素分带,以上特征符合玄武岩型风化淋滤型铜矿的特征。通过对炉山铜矿床地质特征的研究,系统总结出该类矿床的地质特征,为该区相同类型的铜矿勘查工作提供一定的思路。  相似文献   

氮肥及秸秆有益于提高设施番茄土壤芽孢杆菌及假单胞菌的种群数量     

葛晓颖  陈清  孙志刚  何春娥  李涛  欧阳竹 《资源与生态学报(英文版)》2015,6(5):293-301

Root zone N management can reduce N fertilizer input and avoid nitrate pollution in greenhouse tomato production; however, little information is available on how reduced N affects soil microbes, especially dominant bacteria populations in long-term continuous greenhouse systems. This study investigated the effects of different combinations of N and straw on the population size of soil total bacteria and two dominant bacteria (Pseudomonas spp. and Bacillus spp.), and microbial community structure in a 6-year greenhouse tomato trial. The treatments were basal fertilizer (10 t ha-1 chicken manure; control), conventional high N treatment [600 kg N ha-1], conventional high N treatment with wheat straw, reduced N treatment [300 kg N ha-1 less than conventional], and reduced N treatment with wheat straw. Six years of reduced mineral N fertilization did not lead to a decrease in fruit yield. Both mineral N fertilizer and straw increased the numbers of soil bacteria (Bacillus spp. and Pseudomonas spp.) compared with the control, but the numbers were not affected by the amount of mineral N fertilizer (high vs reduced). Different denaturing gradient gel electrophoresis patterns were evidence that soil bacterial communities were changed by N treatments and straw application, but little difference in bacterial diversity was detected between high N and reduced N treatments. These results indicated that a reduction in N fertilizer input was possible in greenhouse tomato production and was beneficial in sustainable agriculture.  相似文献   

Ocean wave parameters retrieved directly from compact polarimetric SAR data   总被引：1，自引：0，他引：1  

Yu Liu  Yijun He  Biao Zhang 《海洋学报(英文版)》2022,41(4):129-137

We aim to directly invert wave parameters by using the data of a compact polarimetric synthetic aperture radar(CP SAR) and validate the effectiveness of ocean wave parameter retrieval from the circular transmit/linear receive mode and π/4 compact polarimetric mode. Relevant data from the RADARSAT-2 fully polarimetric SAR on the C-band were used to obtain the compact polarimetric SAR images, and a polarimetric SAR wave retrieval algorithm was used to verify the sea surface wave measurements. Usin...  相似文献   

独流减河盐沼210Pbexc和137Cs剖面记录的现代洪水事件沉积          下载免费PDF全文

杨彪  王福  田立柱  陈永胜  姜兴钰  王宏  胡克  方晶  李建芬  商志文 《海洋学研究》2016,34(2):25-34

在独流减河入海口附近河道之间的盐沼采用人工探坑侧壁连续取样,获得2个站位的沉积物样品。通过²¹⁰Pb和¹³⁷Cs定年法建立年代框架,结合粒度分析、有孔虫鉴定和水文数据,探讨了该区的现代洪水事件沉积。结果表明,该区沉积物的²¹⁰Pb_exc比活度-深度剖面中存在2处明显的低值沉积层,分别在3~6 cm和10~14 cm深度,这2个沉积层分别对应¹³⁷Cs曲线的次峰和主峰。这两层与上下相邻层位相比呈现粒径较粗、分选较差,有孔虫丰度较低、破损百分比较高的特征。²¹⁰Pb测年结果显示,¹³⁷Cs曲线下部的主峰对应的年龄为1963年,与全球性的最大峰值形成时间相对应,而上部的次峰对应的并非1986年切尔诺贝利核泄漏事故形成的次峰。区内水文数据显示,在1963和1996年分别发生了2次较大的洪水事件。因此,推断S4和S5站位剖面中2个特殊的沉积层是由洪水事件造成的。本研究说明高分辨率沉积特征的多指标研究可以较为准确地揭示洪水等灾害性事件发生的年代和频率,这有利于系统地揭露海陆过渡带地区地质历史时期灾害和气候事件的频率和强度,为灾害预防和未来规划提供科学依据。  相似文献   

青藏高原东部当子沟末次冰期冰川演化光释光测年   总被引：1，自引：0，他引：1  

欧先交  张彪  赖忠平  周尚哲  曾兰华 《地理科学进展》2013,32(2):262-269

青藏高原东部横断山脉沙鲁里山北支雀儿山北麓的当子沟, 保留了4 组末次冰期冰碛垄, 每组冰碛垄由若干道小冰碛垄组成, 是末次冰期多次冰川波动的理想地貌证据。为恢复该地末次冰期冰川演化历史, 从这4 组冰碛垄中采集了7 个光释光测年样品进行年代测定。等效剂量采用单片再生法(SAR)和标准生长曲线法(SGC)进行测试。年代结果显示:第1~3 组冰碛垄形成于22.4-16.5 ka BP, 属深海氧同位素2 阶段(MIS-2), 大致与全球末次盛冰期(LGM)相当。第4 组冰碛垄形成于MIS-3。MIS-3 冰川规模大于MIS-2。第1~3 组9 道次一级小冰碛垄表明, 约在22.4-16.5 ka BP期间当子沟冰川经历了9 次小波动。冰川在稍早于22.4 ka BP达到MIS-2 的最大范围, 此后规模在波动中逐渐萎缩, 可能是冰川对MIS-2 后期太阳辐射增强、气温回升的响应。最里侧冰碛垄形成于16.5 kaBP, 可能标志着该地冰消期的开始。此后, 当子沟冰川大幅快速退缩。冰川融水在最里侧冰碛垄里侧低洼谷地汇集并被阻塞形成当子错。  相似文献   

Serpentinization,abiogenic organic compounds,and deep life     

WANG XianBin  OUYANG ZiYuan  ZHUO ShengGuang  ZHANG MingFeng  ZHENG GuoDong  WANG YongLi 《中国科学:地球科学(英文版)》2014,57(5):878-887

The hydrocarbons and other organic compounds generated through abiogenic or inorganic processes are closely related to two science subjects,i.e.,energy resources and life’s origin and evolution."The earth’s primordial abiogenic hydrocarbon theory"and"the serpentinization of abiogenic hydrocarbon theory"are the two mainstream theories in the field of related studies.Serpentinization generally occurs in slow expanding mid-ocean ridges and continental ophiolites tectonic environment,etc.The abiogenic hydrocarbons and other organic compounds formed through the serpentinization of ultramafic rocks provide energy and raw materials to support chemosynthetic microbial communities,which probably was the most important hydration reaction for the origin and early evolution of life.The superposition of biological and abiological processes creates big challenge to the identification of the abiogenic organic materials in serpentinite-hosted ecosystem.Whether abiotic(inorganic)process can form oil and gas resource is a difficult question that has been explored continuously by scientific community for more than a century but has not yet been solved.However,some important progress has been made.The prospecting practice of abiogenic hydrocarbons in commercial gases from the Songliao Basin,China,provides an important example for exploring abiogenic natural gas resources.  相似文献   

Rock physics modeling of heterogeneous carbonatereservoirs： porosity estimation and hydrocarbon detection   总被引：1，自引：1，他引：0  

Hao Yu  Jing Ba  Jose Carcione  Jin-Song Li  Gang Tang  Xing-Yang Zhang  Xin-Zhen He  Hua Ouyang 《应用地球物理》2014,11(1):9-22

In heterogeneous natural gas reservoirs, gas is generally present as small patch-like pockets embedded in the water-saturated host matrix. This type of heterogeneity, alsocalled ＂patchy saturation＂, causes significant seismic velocity dispersion and attenuation. Toestablish the relation between seismic response and type of fluids, we designed a rock physicsmodel for carbonates. First, we performed CT scanning and analysis of the fluid distributionin the partially saturated rocks. Then, we predicted the quantitative relation between the waveresponse at different frequency ranges and the basic lithological properties and pore fluids.A rock physics template was constructed based on thin section analysis of pore structuresand seismic inversion. This approach was applied to the limestone gas reservoirs of the rightbank block of the Amu Darya River. Based on poststack wave impedance and prestack elasticparameter inversions, the seismic data were used to estimate rock porosity and gas saturation.The model results were in ~ood a~reement with the production regime of the wells.  相似文献   

Occurrence and distribution of phthalate esters in riverine sediments from the Pearl River Delta region,South China   总被引：5，自引：0，他引：5  

Hong Liu  Kunyan Cui  Feng Zeng  Lixuan Chen  Yating Cheng  Huiru Li  Shuocong Li  Xi Zhou  Fang Zhu  Gangfeng Ouyang  Tiangang Luan  Zunxiang Zeng 《Marine pollution bulletin》2014

Sixty-eight sediment samples collected from Dongjiang River, Xijiang River, Beijiang River and Zhujiang River in the Pearl River Delta (PRD) region, Southern China, were analyzed for 16 phthalate esters (PAEs). PAEs were detected in all riverine sediments analyzed, which indicate that PAEs are ubiquitous environmental contaminants. The Σ₁₆PAEs concentrations in riverine sediments in the PRD region ranged from 0.567 to 47.3 μg g⁻¹ dry weight (dw), with the mean and median concentrations of 5.34 μg g⁻¹ dw and 2.15 μg g⁻¹ dw, respectively. Elevated PAEs concentrations in riverine sediments in the PRD region were found in the highly urbanized and industrialized areas. Of the 16 PAEs, diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) dominated the PAEs, with the mean and median concentrations of 1.12 μg g⁻¹ dw, 0.420 μg g⁻¹ dw and 3.72 μg g⁻¹ dw, and 0.429 μg g⁻¹ dw, 0.152 μg g⁻¹ dw and 1.55 μg g⁻¹ dw, respectively, and accounted for 94.2–99.7% of the Σ₁₆PAEs concentrations. Influenced by local sources and the properties of PAEs, a gradient trend of concentrations and a fractionation of composition from more to less industrialized and urbanized areas were discovered. As compared to the results from other studies, the riverine sediments in the PRD region were severely contaminated with PAEs. Information about PAEs contamination status and its effect on the aquatic organisms in the PRD region may deserve further attention.  相似文献   

流动地震台阵观测初至震相的自动检测   总被引：8，自引：0，他引：8       下载免费PDF全文

王继  陈九辉  刘启元  李顺成  郭飚 《地震学报》2006,28(1):42-51

震相到时的自动精确检测对实现海量波形数据自动处理有重要意义. 针对流动地震台阵观测,本文综合利用单台Akaike信息准则（AIC）和多台最小二乘互相关方法,发展了震相自动精确检测技术. 检测结果表明,在长短时平均比值方法（STA/LTA）检测地震事件的基础上,利用单台AIC方法,近震初至震相检测精度小于0.3 s;利用多台最小二乘互相关方法,能够可靠地检测高信噪比地震的初至震相到时,当信噪比较低时,能够有效地避免初至震相的错误判别.   相似文献