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1.
在蒙古南戈壁的Bayan—Khoshuu Ruins剖面原归入到志留系Mandalovoo组尕屋(Gavuu)段的地层中发现了牙形刺Caudicriodus woschimidti woschmidti,这是泥盆纪最早期牙形刺带化石在蒙古的首次发现。尕屋(Gavuu)段的下部属志留系,但其上部,即采集牙形刺样品M-9~M-12的层位肯定属下泥盆统(下洛霍考夫阶),而不是下志留统。Mandalovoo组应当改为Mandalovoo群,它的三个段应提升为三个组。  相似文献   
2.
Lanzhou is a typical mountainous city with severe air pollution in northwestern China. This study uses hourly observational data of air pollutants at five air quality monitoring sites in Lanzhou from July to December 2015 to discuss data quality control and the representativeness of the monitoring sites(four urban sites and one suburban site). A fuzzy matrix is applied to study primary air pollutants. The results show that of the six routinely monitored pollutants,the primary pollutant is PM_10 during the study period. Based on lag correlation analysis and one-way analysis of variance, it is concluded that there are redundant observations at the four urban sites for the timely diffusion and transport of air pollutants from the same general area. The coefficient of divergence(COD) method is then used to evaluate the spatial distribution differences, and the primary air pollutant PM_10 shows differences at each site. COD can be used as a positive indicator to describe site representativeness. To evaluate the overall air pollution in the valley, correlation analysis is performed between the PM_10 concentration retrieved from aerosol optical depth satellite data and the concentration from the four urban monitoring sites. Among these, the correlation between the workers' hospital site data and the retrieval data is the highest, passing the 90% confidence level. A new representative evaluation model for air quality monitoring sites, R_s = 0.77 COD + 0.23R_(retrieval), is established by using COD and correlation coefficients between routine observations and satellite retrieval products. From this model, it can be concluded that the biological products institute site in Lanzhou is the most representative site for the evaluation of air pollution out of the four urban air quality monitoring sites from July to December 2015.  相似文献   
3.
蒙古古生代地层研究的新进展   总被引:1,自引:0,他引:1  
蒙古国古生代地层的研究以往主要侧重底栖大化石的研究, 很多地层的时代划分、归属问题不能得到很好的解决,底栖化石的地方性很强,不能与国际直接对比。 牙形刺是古生代地层的主导化石, 很多古生代地层问题都可以用牙形刺解决并进行可靠的洲际间对比。2001年笔者在蒙古南戈壁采集了158个样品, 经分析发现了大量牙形刺标本, 解决了很多蒙古的重大地层问题。Arynshand组应当归入下石炭统, 泥盆-石炭系界线在Arynshand组之下, 而不是在此组的内部。Mushgai地区Bayan-Khoshuu Ruins剖面的Mandalovoo组Gavuu 段的上部应属早泥盆世早期, 而不是以前所确定的早志留世, 称为奥咯诺伍德组(Olonovoot Formation);Gavuu段的下部仍归早志留世。Mandalovoo组应提升为Mandalovoo群;Gavuu段应提升为Gavuu组。南戈壁Shine Jinst地区Tsakhir剖面Tsagaanbulag组的时代是早泥盆世洛霍考夫期, 而不是中晚志留世,Ulaan-Shand剖面Tsagaanbulag组的时代也是早泥盆世洛霍考夫期。Chuluun组的时代为早泥盆世晚埃姆斯期。Tsagaankhaalga组的时代为早艾菲尔期。Indert组为早石炭世。蒙古古生代海相地层大部分是浅水相地层, 并可能存在5个间断:志留系的文洛克统和罗德洛统的下部,下泥盆统布拉格阶的一部分,中泥盆统艾菲尔阶上部,泥盆-石炭系界线地层。蒙古国南部和中部很可能缺失上二叠统的海相沉积。  相似文献   
4.
蒙古南戈壁新金斯特(Shine Jinst)地区Ulaan-Shand 剖面的查干安普拉格(Tsagaanbulag)组以前曾划归志留系(文洛克统至普里多利统). 但在Tsagaanbulag组及其上部的阿曼采尔(Amansair)组发现了非常重要的牙形刺, 包括Lanea omoalpha, Amydrotaxis johnsoni, “Ozarkodinaplanililingua, Pedavis sp., 清楚地指明这两个组应当归下泥盆统中洛霍考夫阶. 中洛霍考夫阶的海相地层在中国和蒙古国广泛分布. 志留系文洛克统和洛德罗统下部的海相地层在蒙古是否存在是值得注意的问题.  相似文献   
5.
Conodont Caudicriodus woschimidti woschmidti has been found from a big outcrop (hill) of the Bayan-Kho-shuu Ruins Section which was previously assigned to the Silurian Gavuu Member of the Mandalovoo Formation. This isfirst time to find the lowermost Devonian conodont zonal fossil in Mongolia. The lower part of the Gavuu Member is Silurian. But the strata from where we collected samples M-9~M-12 definitely belong to Lower Devonian (lower Lochko-vian) rather than Lower Silurian. The Mandalovoo Formation should be named Mandalovoo Group, and its three members should be changed into three formations.  相似文献   
6.
Mongolia is located within the Central Asian Orogenic Belt. The belt is consist of numerous tectonic blocks or terranes, which resulted from collisions during the Early Paleozoic (Caledonian orogeny), Late Paleozoic (Hercynian orogeny) and partly in Early Mesozoic (Indosinian orogeny) (Seng?r et al., 1993; Heubeck, 2001; Badarch et al., 2003). These collisions had a profound effect on the coal-bearing sedimentary basins in Carboniferous, Permian, Jurassic and Cretaceous periods of Mongolia. A total of more than 200 coal occurrences and deposits are known, of which about 70 have been explored.  相似文献   
7.
贺兰山对银川一次致灾暴雨过程影响的数值模拟   总被引:1,自引:0,他引:1  
贺兰山是中国西北地区干旱区与半干旱区的重要分界线,但是其地形对某些强降水天气过程的影响并不清楚。本文利用WRFV3.4中尺度数值模式,对2012年7月29-30日发生在银川的罕见大暴雨过程进行了数值模拟,并进行了削平贺兰山的敏感性试验。结果表明:贺兰山地形对其东侧银川地区低层绕流气旋的产生、垂直运动、散度场、水汽通量散度都有促进、加强作用,对此次银川大暴雨的产生起了至关重要的作用; 若将贺兰山削平,在贺兰山以西的腾格里沙漠东部地区低层流场将出现切变辐合,垂直运动、散度场、水汽通量散度加强,会导致该地区降水强度增强、范围扩大。这表明,就该区域某些强降水天气过程而言,贺兰山加强其以东银川地区的降水,而对其以西腾格里沙漠东部的降水产生明显的不利影响。  相似文献   
8.
地幔对流被认为是板块运动的驱动力源,但板块说提出35年来,始终未能阐明地幔对流是如何推动板块运动的,也未能证明地幔对流的存在。相反,却有观测与实物证据证明地幔对流并不存在。对地幔对流提出的质疑与剖析,将有助于地球动力学研究思路的扩展。  相似文献   
9.
中国大陆九大名山风景区旅游气候舒适度评价   总被引:5,自引:0,他引:5  
张莹  马敏劲  王式功  尚可政 《气象》2013,39(9):1221-1226
气候舒适度及持续时间的长短,是决定旅游资源质量和旅游季节长短的重要因素。本文采用以温湿指数、风寒指数和着衣指数为基础的综合气候舒适度评价模型,计算了我国具有代表性的九大名山风景区的气候舒适度指数,划分出适宜旅游的等级和时段,并对其随纬度的变化进行了分析。结果表明:位于我国北方的长白山和五台山,气候舒适度年变化呈倒“V”形,舒适期较短,长白山旅游舒适期为6—8月,五台山较舒适期为6—8月;位于我国中部的华山、泰山、黄山和峨眉山,气候舒适度年变化呈倒“U”形,旅游舒适期均为6—9月;位于我国南方的庐山、武夷山和桂林山水,气候舒适度年变化呈“M”形,舒适期较长,庐山旅游舒适期为5—10月,武夷山和桂林山水的旅游舒适期为3—4月与10—11月。  相似文献   
10.
Over arid regions in north-west China, the atmospheric boundary layer can be extremely high during daytime in late spring and summer. For instance, the depth of the observed convective boundary layer can exceed 3,000 m or even be up to 4,000 m at some stations. In order to characterize the atmospheric boundary-layer (ABL) conditions and to understand the mechanisms that produce such an extreme boundary-layer height, an advanced research version of the community weather research and forecasting numerical model (WRF) is employed to simulate observed extreme boundary-layer heights in May 2000. The ability of the WRF model in simulating the atmospheric boundary layer over arid areas is evaluated. Several key parameters that contribute to the extremely deep boundary layer are identified through sensitivity experiments, and it is found that the WRF model is able to capture characteristics of the observed deep atmospheric boundary layer. Results demonstrate the influence of soil moisture and surface albedo on the simulation of the extremely deep boundary layer. In addition, the choice of land-surface model and forecast lead times also plays a role in the accurate numerical simulation of the ABL height.  相似文献   
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