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1.
The latest results from the earth sciences indicated that the movement of the earth surface substances has a close relationship with the energy exchanges on large scale occurred in the margin between the core and mantle. There is a tendency towards the average temperature evolution of the earth dynamic system from higher to lower on the whole. And more and more evidence showed that the interior of the earth is in a non - adiabatic state, the cooling process occurred in the interior exerted a great influence on the surface environment. The development of the heat energy resources from the interior of the earth would result in the long term accelerating cooling though it may increase the surface temperature temporarily.  相似文献   

2.
干热岩地热开发中的钻井、储层压裂及热交换等环节均涉及高温岩石冷却的问题,为揭示其中岩石损伤演化规律,基于巴西劈裂试验和声发射技术,研究了不同高温及冷却方式对花岗岩抗拉性质的影响。结果表明:①25~600℃下花岗岩抗拉强度随温度升高而下降,遇水冷却使抗拉强度进-步下降并使其开始大幅下降的温度阈值提前到200,500℃后抗拉强度对遇水冷却更敏感。②荷载达到峰值,声发射累计振铃计数突增,岩样内形成断裂区;受遇水冷却影响,岩样的振铃计数峰值和能量峰值有所下降,间接反映岩石内裂纹更发育,200~300℃时降幅均较大,300℃时和500℃后花岗岩对热处理方式较敏感。③花岗岩破裂面随温度升高由平整向粗糙曲折变化,由脆性向延性转变,遇水冷却促进岩石破裂并促使脆性向延性转变的温度区间提前。研究结果为地热开采中高温岩石的稳定性评价提供理论参考。   相似文献   

3.
利用卫星重力资料反演地壳及岩石圈厚度   总被引:1,自引:0,他引:1  
地球外部重力场由地球内部物质分布所决定,由于地壳与地幔、岩石圈与软流圈存在着较大的物性差异,利用重力资料可以确定莫霍面和岩石圈底面深度。基于上述结论,利用OSU91全球重力位模型数据进行了反演,计算结果表明,地壳和岩石圈厚度与地形相关,大陆地壳、岩石圈较厚,海洋则相反。  相似文献   

4.
推导了损伤介质中应力场变化与地面位移场和重力变化的关系 ,讨论了利用地面位移和重力场变化来计算地球内应力场变化的边界元方法。利用中国华北地区的 1992~ 1995年的 GPS观测资料对该地区地壳内 15km深处的应力场变化进行了计算 ,并讨论了应力场变化分布与 1996年发生的包头 MS=6 .6级地震的关系 ,结果表明震区的应力场变化明显大于其他地方  相似文献   

5.
In this paper, a heavy sea fog event occurring over the Yellow Sea on 11 April 2004 was investigated based upon observational and modeling analyses. From the observational analyses, this sea fog event is a typical advection cooling case. Sea surface temperature(SST) and specific humidity(SH) show strong gradients from south to north, in which warm water is located in the south and consequently, moisture is larger in the south than in the north due to evaporation processes. After fog formation, evaporation process provides more moisture into the air and further contributes to fog evolution. The sea fog event was reproduced by the Regional Atmospheric Modeling System(RAMS) reasonably. The roles of important physical processes such as radiation, turbulence as well as atmospheric stratification in sea fog’s structure and its formation mechanisms were analyzed using the model results. The roles of long wave radiation cooling, turbulence as well as atmospheric stratification were analyzed based on the modeling results. It is found that the long wave radiative cooling at the fog top plays an important role in cooling down the fog layer through turbulence mixing. The fog top cooling can overpower warming from the surface. Sea fog develops upward with the aid of turbulence. The buoyancy term, i.e., the unstable layer, contributes to the generation of TKE in the fog region. However, the temperature inversion layer prevents fog from growing upward.  相似文献   

6.
由于地质体的质量和之间的结合力不等 ,在地球旋转作用下 ,半球加速、半球减速、半球向心、半球离心、不停交叉、交替作用 ,引起运动的地质体之间的撞动。这是地震的原因。实际是往复潮汐作用、方向改变时引起运动体之间的震动。往复相对运动的地质体之间运动的机械能转化的热能载体 (金属和非金属物质———热气液和岩浆 ) ,在结合面 (层或带 )中储聚、冲开封闭盖层、喷出到地表 ,就是火山的成因。热能熔化的固体岩石和地层形成的岩浆 ,就是岩浆的成因  相似文献   

7.
The Quaternary aggradation red earth(QARE) deposit in the middle reaches of the Yangtze River(MRYR) in southern China provides important evidence for understanding the paleoenvironment. However, its provenance remains controversial. In this study, the surface microtextures of grains from the QARE were observed, and compared with those of grains from the loess deposit on the Loess Plateau in northern China. The results show that the surface microtextures and morphologies of the quartz grains in the QARE are distinctly different from those in the northern loess, indicating that the deposits in the two regions have different provenances. The Gobi and deserts in inland northwestern China are not considered as the primary provenance for the QARE in southern China. It is suggested that the large areas of dry and bare river and lake beds and floodplains in the MRYR, which became exposed during glacial periods, provided the dominant source for materials in the QARE. We suggest that against the background of the middle-Pleistocene climate transition(MPT), regional aridification and a strengthened east Asian winter monsoon(driven by global cooling and the rapid uplift of the Tibetan Plateau) were primary drivers for the initiation of the QARE deposit in the MRYR region in southern China. The development of large areas of aeolian red earth deposit is direct evidence of environmental deterioration in the MRYR, indicating a cold and dry environment with frequent aeolian activity, in an area that now experiences a warm and humid subtropical monsoon climate. The results are also evidence of a regional response in the mid-subtropics of southern China to the MPT global cooling event around 1.2 Ma.  相似文献   

8.
博览群图提升地质制图的科学技术水平   总被引:1,自引:0,他引:1  
地质图件是地质工作成果的主要载体之一,是地质工作服务于经济社会发展的主要工具,又是体现一个国家地质研究程度、地质科学技术水平和社会文明程度的主要标志之一,历来受到各国政府和国际地学组织的高度重视.随着社会经济的发展和科学技术的进步,以及地质工作服务领域的扩大,近年来地质制图工作,包括制图数量、种类和技术方法,都获得了突...  相似文献   

9.
山东莱西市塔埠头稀土矿为一小型伟晶岩型稀土矿床,具有较好的找矿前景。该文通过对塔埠头稀土矿床地质特征、氟碳铈矿物的Th-Pb定年、成矿要素等的综合分析研究,确定了其成矿时代,建立了成矿模式,讨论了矿床成因。研究指出,塔埠头稀土矿床为小型伟晶岩型稀土矿床,主要稀土矿物氟碳铈矿包裹于长石中,2个样品获得的氟碳铈矿Th-Pb加权平均年龄为(128.5±2.0)Ma和(134.4±1.2)Ma。将塔埠头稀土矿成矿要素划分为4个必要要素、3个重要要素,认为在伟晶岩侵入到围岩的降温冷却过程中,形成了塔埠头中生代稀土热液成矿事件。  相似文献   

10.
地壳孕震过程的重力变化研究   总被引:1,自引:1,他引:0  
根据多孔介质中的力学理论,推导了在地壳中存在微孔洞时介质的应力应变本构关系的表示公式,讨论了描述地壳中空洞形成过程的孕震模型参数,讨论了孕震模型参数的变化与地壳介质状态的变化和地面重力变化的关系,并根据乘法分解理论推导了孕震过程计算重力变化的弹塑性递推计算方法,并采用GTN模型进行了数值模拟.在此基础上,将数值模拟结果与发生在1996年云南丽江Ms=7.0地震前后的重力变化进行了对比分析,讨论了微孔洞的形成过程与地面重力变化的关系,较合理地解释了丽江Ms7.0地震前后的重力变化过程.  相似文献   

11.
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12.
基于遥感的城市热环境研究通常通过分析植被、不透水面和地表温度(Land Surface Temperature, LST )的关系来进行。虽然植被的降温作用和不透水面的增温作用已受到普遍认可,但缺少针对降温和增温效率的定量研究,本研究采用地表降温率(Land Surface Cooling Rate, LSCR)和地表增温率(Land Surface Warming Rate, LSWR)量化植被降温效率和不透水面增温效率并对2017年江苏省南京市城市热环境进行分析。以Landsat 8 OLI 4期遥感影像为数据源,利用线性光谱混合分析法(Linear Spectral Mixture Analysis,LSMA)获取亚像元植被覆盖度(Fractional Vegetation Coverage, FVC)、不透水面覆盖度(Impervious Surface Percentage, ISP)并利用高分Google影像进行精度验证。结合地表温度(Land Surface Temperature, LST)反演结果计算各季总体LSCR和LSWR,分析不同LST对总体LSCR和LSWR的影响。最后,将FVC和ISP分别按照阈值平均划分为4个区间,计算各区间的LSCR和LSWR,并在此基础上分析不同区间LSCR和LSWR的变化情况。研究结果表明: ① LST与整体LSCR、LSWR正相关,夏季植被降温效应和不透水面增温效应最强,LSCR和LSWR分别为5.6%和5.1%;② 夏季各区间LSCR与FVC正相关,FVC为75%~100%时LSCR达到最大值7.5%;各区间LSWR与ISP负相关,ISP为75%~100%时LSWR达到最小值2.4%;③ 当FVC为0~25%,ISP为75%~100%时,可以充分发挥植被的降温效应,抑制不透水面的增温效应,是最佳的植被和不透水面组合方案。本研究采用的LSCR和LSWR分析方法可以从抑制地表温度上升的角度选择最佳的FVC和ISP区间,未来可基于此横向对比不同城市,并结合纬度、地形、气候、树种等因素对LSCR和LSWR的影响,进一步探索LSCR和LSWR的影响因子和变化规律。  相似文献   

13.
The heat budget of a melt pond surface and the solar radiation allocation at the melt pond are studied using the 2010 Chinese National Arctic Research Expedition data collected in the central Arctic. Temperature at a melt pond surface is proportional to the air temperature above it. However, the linear relationship between the two varies, depending on whether the air temperature is higher or lower than 0℃. The melt pond surface temperature is strongly influenced by the air temperature when the latter is lower than 0℃. Both net longwave radiation and turbulent heat flux can cause energy loss in a melt pond, but the loss by the latter is larger than that by the former. The turbulent heat flux is more than twice the net longwave radiation when the air temperature is lower than 0℃. More than 50% of the radiation energy entering the pond surface is absorbed by pond water. Very thin ice sheet on the pond surface(black ice) appears when the air temperature is lower than 0℃; on the other hand, only a small percentage(5.5%) of net longwave in the solar radiation is absorbed by such a thin ice sheet.  相似文献   

14.
INTRODUCTIONJiaozhouBayisashallowsemi closedbaywithtotalareaofabout 40 0km2 andaveragewaterdepthof7m .Themaximumwaterdepthisover 5 0matthecenterofthestraitconnectingtotheYellowSea.Thisstraitcenterwateriscalledbaymouthwater,thewaterinthenorthernpartofthestrai…  相似文献   

15.
1 INTRODUCTION In marine waters, water temperature and nutrient Si control the temporal and spatial variation of the phytoplankton growth (Yang et al., 2006). The effect of nutrient Si and water temperature on the mecha- nism of phytoplankton growth has p…  相似文献   

16.
河口地区是人口密集、经济繁荣的区域之一,同时也是生态环境脆弱区,易受到人类活动带来的负面影响,其中热环境恶化问题尤其突出。本文基于多源遥感影像数据,结合遥感技术和统计学方法,研究城市化进程中闽江河口地区20年来的地表温度变化特性;利用Moran's I指数分析研究区表面温度的空间集聚特性及其产生的尺度效应,并定量分析表面温度与不同景观类型的相关性。结果表明:① 1993-2013年,闽江河口地区建设用地面积大幅增加,经历了由慢至快,而后稳中有升的过程;城市扩张是通过大量大规模的边缘式扩张实现的,东部、西部和南部是扩张的3个主要方向。② 地表温度空间格局变化明显,次高温区和高温区显著增加,次低温区和中温区减少,低温区变化不大;高温区扩散方向与建设用地扩张方向基本一致。③ 地表温度存在明显的扰动现象,表现为靠近主城区剧烈,城郊和郊区相对和缓的特性,同时地表温度空间格局具有显著的空间聚集性。④ 建设用地扩张是地表温度增强的重要原因,林/草地和水域能有效缓解区域高温;耕地并未表现出显著的降温效果,但随着耕地比重的增加,地表温度逐渐趋于稳定。研究结果可为改善城市热环境、促进区域可持续发展提供有益参考。  相似文献   

17.
Urban parks composed mostly of vegetation and water bodies can effectively mitigate the urban heat island effect. Many studies have investigated the cooling effects of urban parks; however, little attention has been given to park landscape structure. Based on landscape metrics, this study has explored the influences of the park landscape structure on its inner thermal environment, taking heavily urbanized Beijing Municipality in China as the study area. Three indices, including the percentage of landscape (PLAND), landscape shape index (LSI) and aggregation index (AI), were used to measure the composition and configuration characteristics of the landscape components inside the parks. The indices were calculated for five landscape types being interpreted from Quickbird images. Urban thermal conditions were measured using the land surface temperature (LST) derived from Landsat TM images. The results showed that the park LST had a negative relationship with the park size, but no significant relationship was found with park shape. For the park’s interior landscape, however, the configuration and composition characteristics of the landscape components inside the park explained 70% of the park LST variance. The area percentage of water bodies and the aggregation index of woodland were identified as the key influencing characteristics. In addition, when the composition and configuration characteristics of the park landscape components were separately considered, the configuration characteristics (LSI and AI) explained approximately 54% of the variance in park LST, which was comparable with that explained by the composition characteristics (PLAND). Thus, this study suggested that an effective and practical way for urban cooling park design is the optimization of spatial configuration of landscape components inside the park.  相似文献   

18.
高姗  郑学 《山东国土资源》2022,38(12):70-76
本文以贵阳市为研究对象,研究了地表覆盖组分及植被多样性对地表温度的影响。首先基于Landsat-8 OLI多时相影像数据在GEE平台上实现了研究区域地表覆盖精细分类;然后结合不同季节8天合成的MODIS温度产品数据,利用时空统计分析、相关分析等方法分析了研究区不同地表覆盖类型地表温度时空分布特征,地表温度与不同地表覆盖组分、地表覆盖多样性和植被覆盖多样性的相关性。结果表明:贵阳市建成区主要分布有常绿阔叶林、常绿针叶林等植被,常绿阔叶林在不同季节对地表温度的降温效应明显,而不透水面对地表温度具有明显的增温效应,尤其以夏季最为显著;地表覆盖多样性与地表温度之间具有较强相关性,其中植被覆盖多样性较植被覆盖率对地表温度的影响更为显著,而不透水面的增加会明显降低植被多样性的影响。因此,要发挥城市绿地对城市温度和热岛效应的调节作用,建议可以适当增加常绿阔叶林的绿化面积,同时在空间上要提升植被多样性水平,能够较大程度改善城市热环境。  相似文献   

19.
1 PresentSituationofResearchforGlobalClimateRecently ,theresearchfortheglobalclimatechangescausedbytidehasachievedremarkableresul  相似文献   

20.
The differential rotation between the solid and fluid spheres caused by tidal force could explain the 1500 to 1800-year cycle of the world's temperature. Strong tide increases the vertical and horizontal mixing of water in the oceans, drawing the cold Pacific water from the depths to the surface and the warm water from the west to the east, where it cools or warms the atmosphere above, absorbs or releases CO2 to decrease or increase greenhouse effect and to make La Nina or El Nino occur in the global. The moon's declination and obliquity of the ecliptic affect the tidal intensity. The exchange of tidal energy and tide-generating force caused by the sun, moon and major planets makes the earth's layers rotate in different speeds. The differenti-al rotation between solid and fluid of the earth is the basic reason for El Nino and global climate change.  相似文献   

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