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对古代地震震级的判定——以明代华县地震为例
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作者 吕蕊 《黑龙江史志》 2015年第9期346-347,349,共3页
在现代社会中,人们通过精确地计算来划分地震等级。但在古代社会中,并没有系统的完备的震级划分标准,那么如何确定古代地震的震级。本文以明代华县地震为例,根据史料中相关数据的记载,对比现代地震震级的划分,从而对古代地震的震级做出... 在现代社会中,人们通过精确地计算来划分地震等级。但在古代社会中,并没有系统的完备的震级划分标准,那么如何确定古代地震的震级。本文以明代华县地震为例,根据史料中相关数据的记载,对比现代地震震级的划分,从而对古代地震的震级做出一个初步的判定,希望对研究古代地震有一定的帮助。 展开更多
关键词 震级 烈度 古代地震
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张衡地动仪的诞生 被引量:5
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作者 冯锐 武玉霞 《中国地震》 北大核心 2013年第2期179-197,共19页
地动仪的诞生有着深厚的历史背景,本文旨在探讨张衡科学思想的形成过程和物质基础。张衡生活在东汉文化发展的顶峰时期,"观察异象、辨别凶吉"的朴素愿望是研制地动仪的原始动力。作者追溯了当时的历史背景、张衡的学术历程、... 地动仪的诞生有着深厚的历史背景,本文旨在探讨张衡科学思想的形成过程和物质基础。张衡生活在东汉文化发展的顶峰时期,"观察异象、辨别凶吉"的朴素愿望是研制地动仪的原始动力。作者追溯了当时的历史背景、张衡的学术历程、地动仪的问世过程,分析了东汉早期的地震活动、古代的地震观念和灵台科学活动的特点。指出地动仪的研制起步于公元128年,张衡基于感性认识升华出两个地震概念——地震的位置可按方位判断、地震和地裂必须加以区别,这使地动仪的研制有了明确的技术追求。仪器制作上,张衡崇尚"制器尚象"的原则。地动仪的测震原理模仿了悬挂物(即天然验震器)对地震的反应,技术实现上借鉴了门闩类的触发机构,还通过龙首吐丸的方式留下了发生地震的物质证据,这3个关键问题的解决成就了公元132年地动仪的问世和134年的成功验震,构成他科技创新的完整内容。地动仪的发明深化了人类对自然规律的认识,对当时的东汉及其后世界文化的发展具有积极意义。 展开更多
关键词 地动仪的发明 张衡 古代地震观念 东汉早期的地震活动 悬挂物 触发机构
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How Waterways, Glacial Melt Waters, and Earthquakes Re-aligned Ancient Rivers and Changed Illinois Borders 被引量:2
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作者 Kenneth R. Olson Fred Christensen 《Journal of Earth Science and Engineering》 2014年第7期389-399,共11页
The borders of Illinois were established when Illinois became a state in 1818. The western border was delineated using the Mississippi River, and the Ohio River was used as the southern border. The eastern border was ... The borders of Illinois were established when Illinois became a state in 1818. The western border was delineated using the Mississippi River, and the Ohio River was used as the southern border. The eastern border was formed by the Ohio and Wabash Rivers plus the line along latitude 42030'30'' connecting the Wabash River to Lake Michigan. As initially proposed, the northern border of Illinois would have been 82 km (51 mi) to the south of the current longitude line of 87~31 '. This 2,160,000 ha (5,440,000 ac) addition to Illinois resulted in the territory having the required minimum of 40,000 people to qualify as a state. The northern border was moved to allow the linkage of the Great Lakes shipping route to the Illinois and Mississippi River navigation channels. Illinois thus gained a valuable shoreline on Lake Michigan and a location for a shipping port hub which became Chicago. Initially the transfer of goods between these waterways required a portage, but later a shipping canal was created to link the waterways. During the Civil War, Union forces used the connected waterway systems as a northern supply route to avoid the contested Ohio River. 展开更多
关键词 WATERWAYS Mississippi River Ohio River Illinois territory Illinois borders.
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