排序方式： 共有120条查询结果，搜索用时 78 毫秒
1.
解析联合国教科文组织世界地质公园标准 总被引：1，自引：0，他引：1
2015年11月,世界地质公园正式成为联合国教科文组织的一个品牌,同时颁布了《国际地球科学和地质公园计划章程》(UNESCO,2015a)和《联合国教科文组织世界地质公园操作指南》(UNESCO,2015b),对世界地质公园的管理、组织架构、标准、申报、评估和再评估及活动等提出了明确的要求。中国是世界地质公园的创始国之一,拥有教科文组织世界地质公园的数量居各国之首。几年来的实践表明,一些地质公园和地方政府管理机构对世界地质公园的概念和标准的理解尚存在偏差,造成了工作上的被动局面。本文基于中国世界地质公园的实际状况,针对当前存在的现实问题,对教科文组织世界地质公园的标准进行解析,尤其对其范围、边界、品牌叠加等方面进行详细解读,以期对我国今后教科文组织地质公园的健康发展有所裨益。 相似文献
2.
3.
丹霞山世界地质公园蜂窝状洞穴特征及成因分析 总被引：1，自引：0，他引：1
蜂窝状洞穴以其精致的形貌和众说纷纭的成因吸引着科研人员和普通大众的兴趣。丹霞山世界地质公园蜂窝状洞穴主要产于晚白垩世丹霞组二段(锦石岩段)风成砂岩的崖壁上。本文以园区长老峰锦石岩寺和睡美人禄意堂两处蜂窝状洞穴为研究对象,通过野外实地调查,了解洞穴生长环境,定量统计分析其形态特征,并采集砂岩样品进行显微镜下观察,探讨洞穴形成与盐风化作用的关系。研究表明:蜂窝状洞穴所在的岩性主要为中—细粒长石岩屑砂岩,发育大型高角度交错层理,渗透性较好;洞穴开口均向下朝向锦江,有利于来自锦江河流的湿润水汽较长时间地保持在小洞内部;洞穴开口基本服从泰森多边形分布。因此,碎屑颗粒相对比较均匀的风成砂岩为丹霞山蜂窝状洞穴的发育提供了重要的岩石基础,锦江河流为盐风化提供了必要的湿润水汽和盐分。在初始发育阶段,从岩壁上最适合盐风化作用的若干个点开始形成细小的坑洼,逐步向同层位扩张。单个小洞穴由于盐风化作用,洞穴内部风化速率大于洞穴开口边缘,导致蜂窝状洞穴内部空间扩大较快。然后,蜂窝状洞穴的发育突破纹层的限制,逐步加大、变深而呈泰森多边形规则分布。最终,随着洞穴加深,在重力、风力的影响下,蜂窝状洞穴隔壁减薄失稳,洞穴消亡。 相似文献
4.
广州市增城地质公园发育有大量的燕山期安山岩和流纹岩,由于缺少详细的岩石地球化学研究,这些火山岩的成因和所代表的大地构造意义一直未明确。文章对上述火山岩进行了较为系统的全岩地球化学以及同位素地球化学分析。研究结果显示,安山岩具有安第斯型火山岩特点,显示Nb、Ta、Sr和Ti的亏损,Isr值介于0.70332~0.7144,平均值0.7092,岩石稀土总量较低(ΣREE=158.9×10^-6~215.0×10^-6),平均值186.8×10^-6,轻重稀土元素分异较弱((La/Yb)N5.06~9.87),平均值7.01,Eu负异常不明显(δEu=0.80~1.38),平均值δEu=0.94。流纹岩具有高钾特点,有明显的Ba、Sr、P、Eu、Ti负异常和Pb、Yb正异常,其Isr值介于0.71393~0.73650,平均值0.72615,岩石稀土总量较低(ΣREE=93.4×10^-6~481.5×10^-6),平均值285.7×10^-6,轻重稀土元素分异弱((La/Yb)N=0.65~9.51),平均值4.35,Eu负异常很明显(δEu=0.01~0.03),平均值δEu=0.02,全岩Rb-Sr同位素年龄为(112±12)Ma。综合的地球化学研究表明,增城地质公园安山质-流纹质火山岩均属壳幔混合成因,其中安山岩以幔源为主,而流纹岩则以壳源为主,分别形成于早侏罗世和早白垩世太平洋板块俯冲碰撞挤压的构造背景下。这对华南地区中生代构造演化的深入认识具有重要的地质意义。 相似文献
5.
Hydraulic modeling of flood pulses in the Middle Bussento Karst System (MBSKS), UNESCO Cilento Global Geopark,southern Italy 
下载免费PDF全文
下载免费PDF全文 Karst systems provide water for domestic and industrial uses and for generating hydropower, but they can also create fluvial hazards, such as upstream back‐flooding and downstream karst flash‐flood events. However, these hazards are difficult to foresee due to the complex recharge‐discharge processes as well as the lack of information on the inside of the system, which has often not been completely surveyed by speleologists or explored by boreholes. To overcome these difficulties, hydro‐chemical data from the monitoring system in the Middle Bussento Karst System (MBSKS), one of the first Experimental Karst Systems in southern Italy, were recorded and previously discussed. Based on shared background in flood karst hydraulic modeling, this paper describes the conceptual premises and rationale of a general‐purpose hydraulic model that is suitable both for the MBSKS and for other Mediterranean, multi‐recharge, mature, conduit‐dominated karst systems. To test the reliability of the model, simulations of time–space behavior and response are performed using natural and artificial flood pulses “as tracers”, considering a “pulse” as a significant variation in water quantity and/or quality. The results of the model explain the interactions between allogenic, autogenic, and anthropogenic recharges from differentiated sources and phreatic conduit systems. These results also clarify the overall response of karst springs at typical time scales of flood pulses. Table acronym name 相似文献
6.
深圳地区中生代火山地层分布区是我国东南沿海浙闽粤港火山活动带的一个重要组成部分,是我国沿海地区侏罗纪—白垩纪火山地层较有代表性地段,也是研究我国东南沿海侏罗纪—白垩纪火山活动的天然博物馆。近期通过野外观察,测制火山地层剖面,进行锆石同位素激光定年测试,对大鹏半岛国家地质公园中生代火山地层的时代提出新的认识,将原划分为上侏罗统高基坪群划分为早—中侏罗世塘厦组(181.8 Ma?)、中侏罗世吉岭湾组(165.8 Ma)、晚侏罗世梧桐山组(156.9~145.6 Ma)、晚侏罗世—早白垩世七娘山组(146.3~131.0 Ma)、早白垩世官草湖群等。 相似文献
7.
8.
9.
用户在使用AutoCAD时可能会发现图面实体比较简单,图形文件(DWG文件)却很大,影响文件的调用、存盘和备份.本文针对该问题,以增城市1:2 000地形图精简为例,提出一系列方法帮助DWG文件精简. 相似文献
10.
Geoparks have been established around the world with the major objective of protecting significant geoheritage features and reinforcing geoconservation ideas and support through educating visitors. Understanding visitors' perception of geoheritage can inform educational and conservation endeavors. This study used the visitor-employed photography (VEP) method to unravel visitor perception of geoheritage and associated natural and cultural features in the recently designated Hong Kong Global Geopark of China (HKGP). Participants were asked to take photographs of scenes with an effect on their experience in the HKGP and to elaborate in a logbook the chosen subject, reason of choice, and effect on their travel experience. Aimed at capturing real-time and organic experiences, it was found that geoheritage plays a major role in HKGP visits. Visitors develop strong emotional connections with nature through appreciating and learning about prominent features of both small and landscape scales. However, a mismatch was found between visitor belief or incorrect geological or geomorphological knowledge with inherently strong enthusiasm in deciphering the science behind geoheritage. The findings permit development of a new approach of geopark interpretation, commencing with aesthetic and emotional connections with geoheritage features. Modification of fixed on-site provisions and guiding services directed at visitor interests can better spread geoheritage knowledge and reinforce geoconservation ideas. Modeling after overseas practices, a park ranger system, audio guide devices and smart phone applications are essential to achieve meritorious geopark management, appreciation, and enjoyment. 相似文献