Fractal Determination of Coastal Types Based on GIS--A Case Study of China

The probability of fractal determination of coastal types based on GIS is preliminarily discussed with China as an example. Finally, some significant conclusions are drawn: (1) The fractal dimension of coastline of the bedrock coast is larger than that of the plain coast on the same scale map; (2) As far as the bedrock coast is concerned, the larger fractal dimension of coastline of the bedrock coast on the same scale map indicates that the bedrock coast is probably not typical; (3) As far as the plain coast is concerned, the smaller fractal dimension of coastline of the plain coast on the same scale map indicates that it is probably the silt plain coast; (4) The different substantial compositions affect the fractal dimensions of coastlines of different coastal types. In general, the coast which lies in the north of the Hangzhou Bay consists of sand mainly, its surface is flat, and it is connected with the coastal plain, its landform is broad shoal, its total change is comparatively homogenous in the tidal dynamic process, and thus, the relatively smaller fractal dimension of coastline results from this. For the bedrock coast, there is more bedrock, the coastline is comparatively smooth and straight, being affected by the faults and ocean dynamic process, which result in the larger fractal dimension.     

A community-wide intercomparison exercise for the determination of dissolved iron in seawater

The first large-scale international intercomparison of analytical methods for the determination of dissolved iron in seawater was carried out between October 2000 and December 2002. The exercise was conducted as a rigorously “blind” comparison of 7 analytical techniques by 24 international laboratories. The comparison was based on a large volume (700 L), filtered surface seawater sample collected from the South Atlantic Ocean (the “IRONAGES” sample), which was acidified, mixed and bottled at sea. Two 1-L sample bottles were sent to each participant. Integrity and blindness were achieved by having the experiment designed and carried out by a small team, and overseen by an independent data manager. Storage, homogeneity and time-series stability experiments conducted over 2.5 years showed that inter-bottle variability of the IRONAGES sample was good (< 7%), although there was a decrease in iron concentration in the bottles over time (0.8–0.5 nM) before a stable value was observed. This raises questions over the suitability of sample acidification and storage.     

A probability distribution for depth-limited extreme wave heights in a sea state

A model for the depth-limited distribution of the highest wave in a sea state is presented. The distribution for the extreme wave height is based on a probability density function (pdf) for depth-limited wave height distribution for individual waves [Méndez, F.J., Losada, I.J., Medina, R. 2004. Transformation model of wave height distribution. Coastal Eng, Vol. 50, 97:115.] and considers the correlation between consecutive waves. The model is validated using field data showing a good representation of the extreme wave heights in the surf zone. Some important statistical wave heights are parameterized obtaining useful expressions that can be used in further calculations.     

一种改进的膜盐度计

叙述了一种可用于现场及实验室使用的新的浸入式电池膜盐度计的设计与结构。该膜盐度计传感器由下列电化学电池组成,用此传感器与微机或pH/离子计配合组成了膜盐度计。该仪器可用于近岸河口地区表层海水盐度监测并用于有潮河口底栖动物生态现场研究。仪器现场条件使用准确度约为盐度测量值1％。同时能用于Cl~-及其他离子的现场监测。     

酸溶——催化极谱法测定地质样品中的钨、钼

本文采用混合酸溶解样品,对影响催化体系稳定的酸度、温度和不同反应时间的因素分别进行了对比试验,确定催化体系相对稳定的最佳条件,经过大量样品的分析验证,分析方法可靠。     

中缓倾角结构面分类及其抗剪强度的研究

西南某坝区中缓倾角结构面具有分别倾向上游和下游的空间分布规律。根据结构面接触情况,首先将结构面分为刚性结构面和软弱结构面两大类。其中,刚性结构面属于裂隙型;软弱结构面根据其物质组成和结构特征,可以细分为岩块岩屑型、岩屑夹泥型、泥夹岩屑型3个亚类。断层类结构面具有垂直于断层走向,由高高程到低高程,由泥夹岩屑型岩屑夹泥型岩屑砾型裂隙型逐渐过渡的发育规律。最后在分析抗剪试验资料和分类及发育规律的基础上,提出了抗剪强度指标的建议值。     

国际地磁学与高空物理学协会和国际地震学与地球内部物理学协会联合科学大会及地震电磁研究进展

简要介绍了 2 0 0 1年 8月 1 9～ 3 1日在越南河内召开的国际地磁学与高空物理学协会 ( IAGA)和国际地震学与地球内部物理学协会 ( IASPEI)联合科学大会以及地震电磁研究进展 ,表明地震电磁前兆在地震预测研究中具有一定的实际效果与良好的研究前景。我们建议在不久的将来能在北京举办 IAGA,IASPEI和 IUGG(国际大地测量学与地球物理学联合会 )大会。这将促进我国的科技进步 ,有助于加强我国在国际科学界的地位与影响。     

JRC修正直边法的数学表达

JRC是反映爬坡角力学效应的岩体结构面表面形态等效描述指标。本文在爬坡角力学效应机理研究基础上, 阐述了JRC直边法的物理意义；通过岩体结构面表面起伏幅度与金属表面粗糙度幅度对比分析, 肯定了直边法的合理性；考虑JRC的尺寸效应, 推导JRC修正直边法的数学表达式, 编译计算机常用程序。最后, 实例检验了JRC修正直边法数学表达式的合理性和可用性。     

陕西岚皋地区早志留世滔河口组的厘定及其意义

陕西南部北大巴山地区早志留世滔河口组碱基性火山岩，分布层位稳定，岩性标志特征。根据火山岩岩石类型和地层学以及古生物组合特征对其岩石地层单位重新进行了厘定，研究了火山岩的成因，探讨了火山岩形成的机制和构造环境。     

利用Cole-Cole模型组合得到SIP真参数的联合频谱最优化反演

利用Cole-Cole模型组合和稀释系数理论，可以描述测量得到的视复电阻率频谱与地下多个电性体SIP真参数之间的正演关系。本利用此正演关系进行反演试算，并比较了几种Cole-Cole模型反演方案的效果；提出固定极化目标体和围岩体的极化率同时反演其它各SIP真参数的反演方案。结果表明在固定极化率为真值时，利用此反演方案可以稳定、准确、快速地得出地下电性体SIP真参数。