Improved Kakioka automatic standard magnetometer (KASMMER)     

M. Kuwashima  Y. Sano 《Surveys in Geophysics》1984,6(3-4):357-365

The KASMMER (Kakioka Automatic Standard Magnetometer) has been constructed in 1972 for the standard magnetic observation at Kakioka (Yanagiharaet al., 1973). Then KASMMER system has been improved successively for the high level standard magnetic observation. The purpose of the present paper is to introduce an outline of the improved KASMMER system.The KASMMER system consists of four parts which are four optical pumping magnetometers, a fluxgate magnetometer (Supporting system to the optical pumping magnetometers), a calibration system and a data acquisition system (computer system). The calibration system consists of a proton magnetometer and a magnetic theodolite (Di-72). Details for each part are described and the ability of the improved system is shown to be higher than that of classical magnetic observatory systems.  相似文献   

Fracturing mode analysis and relative age dating of faults by surface textures of quartz grains from fault gouges   总被引：5，自引：0，他引：5  

Yuji Kanaori 《Engineering Geology》1983,19(4):261-281

Surface textures of quartz grains taken from about 250 samples of fault gouges in faults ranging in length from several metres to several tens of metres with the faults extending several tens to several hundreds of kilometres in length, are examined by means of the scanning electron microscope and are categorized into four groups from I to IV, based on the smoothness of the surface, degree of undulation and development of cavities, as mentioned in a previous paper. Based on surface features of quartz grains from faults the geological age of movement of which is known, the groups I to IV are tentatively related to the age of formation of quartz grains and the period of formation of surface textures. This correlation makes it clear that quartz-grain surface textures are an important clue to dating a relative age of faulting. River patterns, striations, granular fracture surfaces, and dimple-like textures are observed to appear on less corroded surfaces of quartz grains from fault gouges. Fractographic analysis of these surfaces of quartz grains should be a clue to revealing the mode of fracture of the fault movement which released the quartz grains into the fault gouge.  相似文献   

Noble gas elemental and isotopic abundances in deep-sea trenches in the western Pacific     

George Igarashi  Masako Kodera  Minoru Ozima  Yuji Sano  Hiroshi Wakita  Jacques Boulgue 《Earth and Planetary Science Letters》1987,86(1)

Noble gas elemental and isotopic abundances were measured in seven deep-sea water samples from five different sampling sites in the Nankai Trough, the Japan Trench and the Kuril Trench. The samples were obtained by the manned submersible “Nautile”. Most of the sampling sites are associated with clam colonies and/or fluid venting. Excesses both in³He/⁴He ratio and He concentration are observed in a seawater sample collected a few kilometers off the clam colonies which were found at a depth of 3830 m at the mouth of the Tenryu Canyon. Concentrations of noble gases (Ne, Ar, Kr and Xe) in this sample show progressive depletion from Ne to Xe relative to those in 1°C air-saturated seawater, which can be attributed to mixing of hot water ( 15°C) with cold ambient water ( 1°C). Isotopic compositions of Ne, Ar, Kr and Xe in this sample are atmospheric. These observations may reflect venting of hot pore water around the Tenryu Canyon. All the other samples show a significant excess in concentration of all noble gases relative to 1°C air-saturated seawater and the isotopic compositions are atmospheric. This excess of noble gas concentrations may appear to be air contamination in the samples. However, results of hydrocarbon analyses of the Kaiko samples imply that such large amount of air contamination is improbable. Decomposition of gas hydrate in deep-sea sediments is a more likely explanation for the observed excess of noble gas concentration.  相似文献   

Precise temperature measurement of groundwater for earthquake-prediction study   总被引：2，自引：0，他引：2  

Yuji Nakamura  Hiroshi Wakita 《Pure and Applied Geophysics》1984,122(2-4):164-174

Precise measurements of groundwater temperature, with a resolution of 0.0001°C, have been made for the purpose of earthquake prediction at four water wells in the Tokai district in Japan. The characteristics of temporal variations in groundwater temperature differ from well to well. From records of a well located in an area where use of groundwater is heavy, movement of groundwater was sensed by temperature variations. By contrast, water temperatures in a 500 m well far from cultural areas were extremely steady, with fluctuations of less than 0.0005°C. This well appears to be suitable for monitoring possible temperature changes related to the occurrence of an impending large earthquake.  相似文献   

基于SKS分裂研究长白山区上地幔各向异性特征     

宋雨佳  盘晓东  康建红 《地质论评》2024,70(S1):129-130

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自然资源定义、分类，观测监测及其在国土规划治理中的应用          下载免费PDF全文

付宇佳  谭昌海  刘晓煌  孙兴丽  袁泽民  郑艺文 《中国地质》2022,49(4):1048-1063

【研究目的】为摸清中国资源家底、认清资源变化规律、管好国土用途，解决现有自然资源内涵不一、分类上存在差异、在数据获取上不统一、资源管理分属不同部门导致的资源在空间管理上交叉重叠等问题。【研究方法】本文采用文献综述法对自然资源的定义、分类及有关资源观测监测指标的相关文献进行梳理。【研究结果】（1）明确了观测监测体系下的自然资源是自然状态或未被加工的状态下通过生产能够产生价值的资源，可将其分为气候资源、地表覆盖资源及地下水资源3类开展研究；（2）总结得到自然资源综合观测与监测的对象、内容及观测方法；（3）分析自然资源观测监测在资源间及资源与环境间、资源资产管理、生态环境修复上的具体作用。【结论】文章最后指出自然资源观测监测是研究资源间、资源与环境间作用，资源资产管理以及生态环境修复中不可缺少的技术手段。创新点：（1）明确了自然资源的定义，解决自然资源在部门管理上、分类上以及数据获取上不统一的问题；（2）分析自然资源观测与监测的内容和指标，结合系统调查、观测实验、预测模拟、监测评价“四位一体”的探测技术，有效掌握自然资源家底、进行资源资产管理，研究资源间、资源与环境的相互关系，在国土规划治理中发挥作用。  相似文献   

黑海西北部多瑙河峡谷北侧陆坡沉积特征及其与古气候的关系          下载免费PDF全文

张艺璇  白辰阳  刘宇佳  杨海琳  LIVIORuffine  赖勇  卢海龙 《中国地质》2022,49(3):880-900

【研究目的】在末次冰期，全球气候变化以千年尺度的快速、大幅度温度波动旋回为特征，这种波动变化在两极冰芯、深海沉积、中国黄土和洞穴石笋等诸多地质样品中均有记录。黑海位于北大西洋与东亚季风区过渡带，具有极有代表性的沉积记录。本文旨在通过对黑海沉积序列的研究，建立起其区域环境变化与北大西洋及东亚季风气候域气候变化的联系。【研究方法】研究对取自黑海西北部罗马尼亚陆坡区多瑙河峡谷北侧GAS-CS12钻孔的长22.0 m的岩芯样品，进行了粒度、矿物成分、主量元素、有机碳、总氮及碳氮同位素等分析。【研究结果】揭示出该段岩芯沉积于末次冰期中后期“Neoeuxine”湖相阶段，可划分为5个沉积单元，对应于北大西洋H4、H3、H1气候变化事件、末次冰盛期（LGM）及Bolling-Allerod气候变暖事件。【结论】建立起了其沉积序列及区域环境变化与北大西洋及东亚季风气候域气候变化的联系，印证了末次冰期千年尺度的气候变化事件在北大西洋、东亚季风区及两者过渡带上具有高度的一致性。创新点：建立了黑海西北沉积序列与区域环境变化的关系；补充了北大西洋与东亚季风区两者过渡带上气候波动事件的可靠时标。  相似文献