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利用多目标区域地球化学调查成果,探讨了福建沿海土壤地球化学分类的方法,提出了分类命名方案和诊断标准,将研究区土壤按SiO2含量划分为铁铝土、硅铝土、铝硅土、硅土4个大类,其中硅铝土又分为一般硅铝土、铁质硅铝土、钾质硅铝土、硫铁质硅铝土4个亚类,铝硅土分为一般铝硅土和钾质铝硅土2个亚类;提出了在各种统计量中,中值比较客观地反映元素含量背景,适合作为基准值;给出了研究区各类土壤的分布图和52种元素及pH的基准值,分析了其成因和农业利用情况。 相似文献
104.
数字化形变台站日常下载、处理直至管理数据,都应用《数字化通讯控制软件》、《形变前兆台站(网)数据处理系统》及《形变前兆数据库服务软件(台站版)》等三个软件交互进行,在实际使用过程中会遇到一些棘手的问题。本文结合我台的观测工作的实践,总结经验,以供台站同行共享。 相似文献
105.
本文对福建省水氡观测资料变化规律进行分析,并试图利用相对均方差、拟合噪声水平和相对年变幅等三项指标,对福建省8个水氡点的观测资料质量进行初步探索。 相似文献
106.
正20141574 Chen Hao(Exploration and Development Research Institute,Daqing Oilfield Company,Daqing 163712,China)High-Resolution Sequences and Coal Accumulating Laws in Nantun Formation of Huhe Lake Sag(Petroleum GeologyOilfield Development in Daqing,ISSN1000-3754,CN23-1286/TQ,32(4),2013,p.15-19,5 illus.,15 refs.)Key words:coal accumulation regularity,coal 相似文献
107.
福建政和上山岗金银矿位于政和—大埔深大断裂带东侧的东坑火山盆地中,为受断裂控制的火山-次火山热液型金银矿床。通过对矿区地质构造的研究,认为矿区断裂发育,主要有NE向、NW向、近EW向和近SN向4组,均为控岩-控矿构造,为矿区内重要的找矿标志。其中,NE向和近SN向断裂为主要的控矿和容矿构造,NW向和近EW向断裂为主要的控岩构造,常切割破坏矿体。金银矿体(脉)的产出严格受火山盆地中的断裂控制,与赋矿围岩的具体岩性关系不明显;矿体(脉)的大小与所在断裂的规模密切相关。矿区外围及深部与主干断裂平行的次级断裂可作为矿区进一步找矿的有利构造。 相似文献
108.
Sampling efforts are constrained by limited availability of resources. Therefore, methods to reduce the number of samples, while still achieving reasonable accuracy are needed. Land-surface segmentation (LSS) has proven a powerful technique to partition digital elevation models (DEMs) and their derivatives into relatively homogeneous areas, which can be further employed as support in soil sampling. Though topography is one of the main soil forming factors, a robust assessment of the potential of this technique to digital soil mapping (DSM) is still missing. In this study, we aimed at evaluating the potential of LSS in stratifying a landscape into relatively homogeneous areas, which can be used as strata for guiding the selection of sampling points in DSM. The experiments were carried out in two study areas where soil samples were available. Land-surface derivatives were derived from DEMs and segmented with a tool based on the multiresolution segmentation algorithm, into objects considered as homogeneous soil-landscape divisions. Thus, one sample was randomly selected within each segment from the existing sample data, based on which predictions of soil classes/sub-orders and properties, i.e. soil texture and A-horizon thickness, were made. Results were compared with predictions based on simple random sampling (SRS) and conditioned Latin hypercube (cLHS). The segmentation-based sampling (SBS) scheme performed better than SRS and cLHS schemes in predicting the A-horizon thickness, soil texture fractions and soil classes, showing a high potential of LSS in stratifying a landscape for the purposes of DSM. The novelty of this study is in the way strata are constructed, rather than in the sampling design itself. Further research is needed to demonstrate the value of a SBS design for practical use. The analyses presented here further highlight the importance of considering locally adaptive techniques in optimization of sampling schemes and predictions of soil properties. 相似文献
109.
Huadong Guo Yubao Qiu Massimo Menenti Fang Chen Paul F. Uhlir 《International Journal of Digital Earth》2018,11(7):657-669
The Belt and Road initiative has a significant focus on infrastructure, trade, and economic development across a vast region, and it also provides significant opportunities for sustainable development. The combined pressure of climate variability, intensified use of resources, and the fragility of ecosystems make it very challenging, however, to achieve future sustainability. To develop the path in a sustainable way, it is important to have a comprehensive understanding of these issues across nations and evaluate them in a scientific and well-informed approach. In this context, the Digital Belt and Road (DBAR) program was initiated as an international venture to share expertise, knowledge, technologies, and data to demonstrate the role of Earth observation science and technology and big Earth data applications to support large-scale development. In this paper, we identify pressing challenges, present the research priorities and foci of the DBAR program, and propose solutions where big Earth data can make significant contributions. This paper calls for further joint actions and collaboration to build a digital silk road in support of sustainable development at national, regional and global levels. 相似文献
110.
福建及沿海地区地震活动力源探讨 总被引:6,自引:0,他引:6
综合地震震源机制解和地壳形变观测资料的研究, 求得福建及其沿海地区现代震源应力场, 认为这与台湾地区、 台湾海峡应力场相互衔接, 主压应力轴优势方位为NW-SE向, 力轴仰角较小, 应力场近于水平挤压, 形变场反映近期福建沿海亦受北西方向, 接近与海岸垂直的挤压力。 进一步分析该区域内的断裂构造特征和地震活动强度由东至西逐渐减弱的规律, 认为菲律宾海板块与欧亚板块的相互作用力不仅是台湾强震力源所在, 而且其影响向西扩展, 福建及其沿海地区地震活动主要力源仍然是来自这两大板块的相互作用力。 相似文献