复盘河南“21·7”极端降水的可预报性及对决策气象服务的思考     

赵培娟  胡玉梅  孔海江 《气象与环境科学》2022,45(2):38-51

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凸起凹陷构造控矿及找矿探讨——以泰安市区为例          下载免费PDF全文

宗信德  赵宏生  彭超  方传昌  张俊峰  赵亚军 《山东国土资源》2011,27(12):1-6

在泰安市所辖6个县市区范围内,分布着以铁、金等为主的金属矿产和以煤、石膏等为主的非金属矿产。两类矿产分别赋存于呈近SN向相间排列的5个凸起和5个凹陷构造中,铁、金等矿赋存于凸起,煤、石膏等矿赋存于凹陷。对凸起构造特征分析认为,南北方向相邻的凸起、凹陷构造本是一体,凹陷深部与凸起有相似的地质条件,相似类比理论为地质找矿工作提供了空间,应树立综合找矿和缺位找矿的思想,整合矿业权,实行整装统筹勘查。  相似文献   

Massive scalar field quasinormal frequencies in black hole with a deficit solid angle     

Chunyan Wang  Yajun Gao 《Astrophysics and Space Science》2013,344(2):447-450

Massive scalar field quasinormal modes of black hole with a deficit solid angle are studied by using the third-order WKB approximation. From the numerical results obtained, we find that scalar field with higher mass u will oscillate more quickly but decay more slowly, while with larger deficit solid angle ε will oscillate and decay more slowly. Moreover, the imaginary parts of quasinormal frequencies are almost linearly related to the real parts with u and ε.  相似文献   

北京西山鹫峰地区氢氧稳定同位素特征分析   总被引：4，自引：0，他引：4  

邓文平  余新晓  贾国栋  李亚军  刘玉洁 《水科学进展》2013,24(5):642-650

以北京西山鹫峰低山区为研究对象,通过对降水、土壤水、泉水氢氧同位素的变化特征分析,研究低山区的降水-土壤水-泉水的转化关系。研究结果表明:该地区的雨季降水线与北京地区的地区降水线有明显区别,斜率和截距偏小;随降雨的进行氢氧同位素特征有时程变化和降雨量效应,而降雨的时程变化也对土壤水的同位素特征产生了影响;土壤水分同位素分布特征相对集中,蒸发线方程的斜率和截距相对于当地大气降水线和雨季降水线都偏小,栓皮栎混交林土壤水对于小雨量次降雨事件反应不敏感,而侧柏林的土壤水分运动较栓皮栎混交林快,说明林分类型和土壤特性对不同水体之间的转化有影响;泉水的同位素特征比较稳定,主要分布在地区降水线的右下方与雨季降水线的交点附近;不同水体中降雨的δD、δ18O变化范围较大,土壤水次之,泉水变化最小;而沿着大气降水-土壤水-地下水(泉水)这一水循环路径,水体中的δD、δ18O值总体上呈下降趋势。  相似文献   

中国重要生态保护区域人类干扰时空变化特征分析   总被引：1，自引：0，他引：1  

刘晓曼  王超  肖如林  付卓  吕娜  袁静芳  侯鹏 《地理科学》2022,42(6):1082-1090

构建人类干扰指数,从时间和空间双重角度,评估中国重要生态保护区域人类干扰变化特征。研究表明：① 总体来说,2018年中国重要生态保护区域人类干扰低于全国平均水平,1980―2018年,和全国平均水平相比,中国重要生态保护区域人类干扰增加幅度小、增长趋势慢,定量说明中国重要生态保护区域人类活动整体管控成效好;② 1980―2018年,3类重要生态保护区域（国家级自然保护区、生物多样性优先区、重点生态功能区）人类干扰指数均呈逐步增加趋势。以“胡焕庸线”为界,重要生态保护区域以西、以北人类干扰总体较小,增加相对缓慢;以东、以南人类干扰相对明显,增加也相对明显,今后对这些区域要重点加强管控;③ 国家级自然保护区人类干扰指数在5个监测年份均最低,增加趋势最平缓、增幅最小,人类活动实际管控成效最好;重点生态功能区和生物多样性优先区人类干扰相对较大,管控成效有待显现,结果反映中国对重要生态保护区域分类管控力度和梯度的差异;④ 重要生态保护区域内部人类干扰指数及增幅均低于外部未受保护区域,构建重要生态保护区域有效降低人类干扰。  相似文献   

胶东半岛及两侧海域尾波Q值分析     

李霞  张志慧  许萍  李亚军 《地震地磁观测与研究》2008,29(2):14-20

根据单次散射（Aki）模型,利用2003年至今山东台网记录的26次2．9级以上地震的数字化地震波,研究并探讨了胶东半岛及两侧海域平均尾波Q值,在1～18Hz的频率域范围内,Q值与频率的依赖关系为：胶东北部海域Qc=（313士42）,f^（0.653±0.145）,胶东内陆Qc=（319±88）f^（0.649±0.145）,黄海海域Qc=（259±60）f^（0.757±0.277）,与国内其他区域尾波Q值研究结果相比,本区域Qc为高值、对频率低依赖性区域。可能与本研究区内构造活动弱、地震活动水平低有关。  相似文献   

柴达木盆地南八仙地区渐新世浅水三角洲物源及沉积演化     

易定红  石亚军  刘俊丰  刘应如  李积永  王爱萍  马元坤  李红哲  贾正良 《地质学报》2024,98(2):494-510

以古近系渐新统下干柴沟组上段(E23)为研究对象,在精细岩芯观察和钻(测)井资料综合分析的基础上,结合重矿物组合、ZTR指数、砂岩碎屑组分、粒度累积概率图和砂地比等参数综合分析结果,对柴达木盆地南八仙地区E23湖盆扩张期弱退积型浅水三角洲物源方向、砂体展布规律和沉积微相发育演化进行了深入研究。结果表明：① 南八仙地区E23沉积时期物源主要来自南祁连山中酸性岩浆岩和中高级变质岩发育区,物源方向为近北东—南西向,稳定重矿物(磁铁矿、石榴子石、白钛矿和锆石)含量高(质量分数介于81. 0%~99. 9%)、不稳定重矿物(绿帘石和角闪石)含量低。② 南八仙地区E23沉积时期为浅水三角洲—滨浅湖沉积环境,主要发育水下分流河道砂体,岩性主要为岩屑长石砂岩,其次为长石岩屑砂岩,砂体的成分成熟度一般中等—较差、分选磨圆度中等—较差,粒度概率图以反映河流作用的一跳跃一悬浮式为主;沉积构造类型多样,主要发育块状层理、正粒序层理、平行层理和槽状交错层理。③ E23沉积时期,南八仙地区继承性发育3条北东—南西向呈条带状展布的砂体富集带(砂地比值介于35%~65%之间),早期到中期砂体发育程度增强,呈进积式;中期到晚期砂体发育程度有所减弱,呈弱退积式。④ E23沉积时期,南八仙地区处于浅水三角洲前缘亚相沉积环境,持续发育3个呈北东—南西向展布的沉积朵叶体,主要发育水下分流河道微相,其次为水下分流间湾微相,早期到中期浅水三角洲前缘发育规模增大,中期到晚期发育规模减小。  相似文献   

酸化过程对不同碳酸钙含量的海洋沉积物中总氮及其同位素分析的影响     

彭亚君  刘东艳  王玉珏  RICHARD Pierre  KEESING John K. 《海洋学报(英文版)》2018,37(8):1-5

为节约成本和样品，一些学者同时分析海洋沉积物中的碳、氮及其同位素（TOC、TN、δ¹³C和δ¹⁵N）。分析沉积物中的δ¹³C，需要对样品进行酸化去除无机碳，但是这一酸化过程会使TN和δ¹⁵N的分析结果产生偏差，且偏差范围与沉积物中无机碳含量（CaCO₃）有关。本研究选取了低CaCO₃含量（1-16%）和高CaCO₃含量（20-40%）的海洋沉积物样品，比较了酸化过程对TN和δ¹⁵N的影响。研究结果表明，酸化过程对海洋沉积物中TN和δ¹⁵N的分析结果产生了显著影响。对于低CaCO₃含量的样品，酸化导致样品中TN流失了约0-40%，δ¹⁵N偏移了约0-2‰；而对于高CaCO₃含量的样品，酸化导致样品中TN流失了约10-60%，δ¹⁵N偏移了约1-14‰。表明酸化对TN和δ¹⁵N的影响已经超过了仪器的误差范围0.002%（TN）和0.08‰（δ¹⁵N），将影响TN和δ¹⁵N的环境指示意义。因此，即使海洋沉积物样品中CaCO₃含量很低，也必须用原样分析TN和δ¹⁵N以避免酸化过程的影响。  相似文献   

Numerical simulation of the climate effect of high-altitude lakes on the Tibetan Plateau     

YinHuan Ao  ShiHua Lyu  ZhaoGuo Li  LiJuan Wen  Lin Zhao 《寒旱区科学》2018,10(5):379-391

Lakes regulate the water and heat exchange between the ground and the atmosphere on different temporal and spatial scales. However, studies of the lake effect in the high-altitude Tibetan Plateau(TP) rarely have been performed until recently, and little attention has been paid to modelling of frozen lakes. In this study, the Weather Research and Forecasting Model(WRF v. 3.6.1) is employed to conduct three numerical experiments in the Ngoring Lake Basin(the original experiment, an experiment with a tuned model, and a no-lake experiment) to investigate the influences of parameter optimization on the lake simulation and of the high-altitude lake on the regional climate. After the lake depth, the roughness lengths, and initial surface temperature are corrected in the model, the simulation of the air temperature is distinctly improved. In the experiment using a tuned model, the simulated sensible-heat flux(H) is clearly improved, especially during periods of ice melting(from late spring to early summer) and freezing(late fall). The improvement of latent-heat flux(LE) is mainly manifested by the sharp increase in the correlation coefficient between simulation and observation, whereas the improvement in the average value is small. The optimization of initial surface temperature shows the most prominent effect in the first year and distinctly weakens after a freezing period. After the lakes become grassland in the model, the daytime temperature clearly increases during the freezing and melting periods; but the nocturnal cooling appears in other stages, especially from September to October. The annual mean H increases by 6.4 times in the regions of the Ngoring Lake and the Gyaring Lake, and the LE declines by 56.2%. The sum of H and LE increases from 71.2 W/m2(with lake) to 84.6 W/m2(no lake). For the entire simulation region, the sum of H and LE also increases slightly. After the lakes are removed, the air temperature increases significantly from June to September over the area corresponding to the two lakes, and an abnormal convergence field appears; at the same time, the precipitation clearly increases over the two lakes and surrounding areas.  相似文献   

Simulating the role of gravel in freeze–thaw process on the Qinghai–Tibet Plateau     

Pan  Yongjie  Lyu  Shihua  Li  Suosuo  Gao  Yanhong  Meng  Xianhong  Ao  Yinhuan  Wang  Shujin 《Theoretical and Applied Climatology》2017,127(3-4):1011-1022

Soils containing gravel (particle size ≥2 mm) are widely distributed over the Qinghai–Tibet Plateau (QTP). Soil mixed with gravel has different thermal and hydrological properties compared with fine soil (particle size <2 mm) and thus has marked impacts on soil water and heat transfer. However, the most commonly used land models do not consider the effects of gravel. This paper reports the development of a new scheme that simulates the thermal and hydrological processes in soil containing gravel and its application in the QTP. The new scheme was implemented in version 4 of the Community Land Model, and experiments were conducted for two typical sites in the QTP. The results showed that (1) soil with gravel tends to reduce the water holding capacity and enhance the hydraulic conductivity and drainage; (2) the thermal conductivity increases with soil gravel content, and the response of the temperature of soil mixed with gravel to air temperature change is rapid; (3) the new scheme performs well in simulating the soil temperature and moisture—the mean biases of soil moisture between the simulation and observation reduced by 25–48 %, and the mean biases of soil temperature reduced by 9–25 %. Therefore, this scheme can successfully simulate the thermal and hydrological processes in soil with different levels of gravel content and is potentially applicable in land surface models.

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