浙江省铜矿床的稳定同位素地球化学特征     

胡永和  徐有浪  朱兴盛 《浙江国土资源》1994,(2)

浙江省铜矿床硫化物的矿δ34S值一般变化在-6‰～＋10．5‰之间，以正值为主，大多富集重硫，接近陨石硫；矿石铅同位素组成，在铅构造模式图上只有细碧角斑岩型和混合岩化型矿床的值域位在上地幔和下地壳曲线之间，其它类型（包括矽卡岩型、斑岩型和热液型等）矿床位于造山带曲线之上。这反映了不同类型铜矿床的成矿物质来源存在着差异。浙江省铜矿床的氢、氧同位素组成，矿物的δ18O多为正值，变化范围为＋4‰～＋12‰之间，在δ18O水—δD相关图上，细碧角斑岩型矿床具低δ18O水值高δD值域，混合岩化型矿床为高δ18O水值低δD值域的特征，这表明它们的成矿流体分别混合有海水和变质水的特征，其它类型矿床的成矿流体则多为岩浆水与大气降水的混合型。  相似文献   

吉泰盆地夏季一次暴雨天气过程中尺度对流系统演变特征          下载免费PDF全文

李婕  占龙飞  徐星生  金米娜  孙素琴 《气象与减灾研究》2022,45(4):241-252

利用地面气象观测、FY 2G卫星TBB、多普勒雷达、ERA5再分析资料,以及江西快速循环同化系统等资料,分析了2020年7月9日吉泰盆地梅雨期特大暴雨天气过程的中尺度系统演变特征及机制。过程分为线状对流系统MCS A转向、南压阶段和单体对流系统MCS B、MCS-C北移发展阶段。结合盆地西侧山区、盆地北部、盆地南部三个暴雨区,重点分析了暴雨天气过程的第一阶段。结果表明：1） 边界层辐合线触发MCS-A,后者西侧不断并入边界层辐合线上和低空急流前端的新生单体,形成“列车效应”。2） 弱降水冷池驱动MCS A中强降水雨团向西南方向传播以及MCS-A与弱降水雨团合并,共同导致了MCS-A转向。3） 受幕府山和吉泰盆地地形绕流作用,对流层中低层中-β尺度低涡在吉泰盆地东北部停留约5 h,激发盆地西部、北部对流活动的发展。4） 对流系统处于准静止态,急流前端存在中-γ尺度涡旋,导致MCS-A中强对流单体在吉泰盆地南部长时间维持。  相似文献   

CMA-GD模式江西省智能网格预报区域2 m气温预报误差分析          下载免费PDF全文

李健  张瑛  胡庆荣  徐星生 《气象与减灾研究》2023,46(1):35-43

利用2020年6月1日—2022年5月31日CMA GD模式2 m气温预报产品（预报时效为13—36 h）和同期江西省智能网格预报区域内地面站气温观测资料,计算气温预报准确率、平均误差和均方根误差,并统计分析其时空分布特征。结果表明： 1）模式预报准确率在不同月份、起报时次存在差异,暖季总体较高,冷季总体较低;暖季08时起报产品的月准确率总体高于20时,冷季反之;秋、冬季旬准确率分布更离散。模式预报产品其准确率明显低于中央气象台和江西省气象台订正产品,需订正后使用。08时起报产品对寒潮的预报效果优于20时。2）气温预报年误差分布存在日变化,最大值出现在08时,最小值出现在15时;年均方根误差峰值出现在15时和06时,白天大于夜间。3）冬季平均误差多为正值,夏季为负值,春、秋季平均误差大小界于冬、夏季之间;白天时段夏季均方根误差最大,夜间时段冬季最大。4）气温预报年误差地理分布特征明显,平原地区预报值偏低,年均方根误差最小;丘陵和山区22 h时效预报值偏高,31 h时效偏低;高山站预报值偏高,年均方根误差最大。丘陵地区负误差最大,平原地区最小;山区正误差最大。  相似文献   

RESEARCH ON SURFACE O_3 WITH METEOROLOGICAL CONDITIONS UNDER ATMOSPHERIC BACKGROUND CONDITIONS IN NORTHEAST CHINA     

丁国安  徐晓斌  向荣彪  李兴生  张忠华 《Acta Meteorologica Sinica》1997,(4)

Surface O_3 concentration and its precursors have been observed at Longfengshan station,Heilongjiang Province for a period of one year from August 13,1994 to July 30,1995.Relationship between surface O_3 and the meteorological conditions during this period is analyzed inthis study.Observation results show that diurnal variation of surface O_3 follows a pattern ofdouble-peaks with amplitude of 27—28 ppb under fine days in summer and autumn.Although thediurnal variation is small(14 ppb),it is still detectable when it is overcast.Diurnal variation of O_3is irregular under rainy days.Surface O_3 concentration rises when wind speed starts to increase at0800 BT(Beijing Time)from 0 to 6 m s~(-1)in autumn,winter and summer.Relative high surfaceO_3 concentration is noticed frequently when S,SSW,SW and WSW wind are encountered at thestation during all seasons.At 0800 BT and 1400 BT the surface O_3 concentration increases with theincrease of global radiation accordingly during fine days in winter,spring and autumn.During finedays average peak of O_3 concentration in summer is 20 ppb higher than that in winter while theaverage peak of global radiation in summer is almost twice as high as that in winter.The averagesurface O_3 concentration under fine days in autumn at Longfengshan station is 14 ppb lower incomparison to the observation results from Lin'an station where Lin'an is at about the samelongitude and lower latitude,with same environment,which is mainly caused by the difference ofglobal radiation due to different latitudes in these two areas(difference of average peak globalradiation about 100 W m~(-2)).  相似文献   

一种新的成矿预测方法—构造分形异常法─—以芙蓉山地区为例     

徐有浪  胡永和  朱兴盛  王海棠 《浙江国土资源》1998,(2)

通过对LandsatE5TM数据的线性信息解译和分形统计学的方法,研究了浙江省芙蓉山地区断裂构造的空间分布特征,并通过构造分组数D值表征断裂构造的空间分布强度来指示矿化的空间分布,在该地区火山岩的找金工作中取得了一定的进展。这种将TM数据解译与分形统计学结合的构造分形异常法应用方便、简捷,若进一步将其与物化探异常相结合,效果可能会更好。  相似文献   

INTERCOMPARISON OF OZONE VERTICAL PROFILES BETWEEN ECC OZONESONDE AND BREWER UMKEHR MADE OVER QINGHAI PLATEAU OF CHINA     

刘奇俊  郑向东  罗超  汤洁  丁国安  李兴生  周秀骥 《Acta Meteorologica Sinica》1998,(1)

From October 1995 to August 1996.a total of 50 ECC(electrochemical concentration cell)ozonesoundings were made in Xining(36.43°N,101.45°E,2296 m ASL)to study the distributionand seasonal characteristics of ozone profile,and intercompare the Brewer Umkehr ozone profilesobtained at Waliguan Baseline Station over the Qinghai Plateau.It was demonstrated that(1)Umkehr produced estimates of the ozone comparing with ECC profiles were accurate to better than25% in the 20—38 km altitude range,and where 23—33 km region was the most accurate,withinabout 15% of the ECC ozonesonde:(2)higher differences between Brewer Umkehr and ECCozonesonde occurred in the troposphere and lower stratosphere;and ozone amounts wereoverestimated in Umkehr layers 1,2 and 3,and were underestimated in Umkehr layers 6 and 7 byBrewer Umkehr method.  相似文献   

Dimethyl sulfide in the atmospheric surface layer of the Equatorial Pacific Ocean     

Li Xingsheng  F. Parungo  C. Nagamoto  S. Hoyt 《海洋学报(英文版)》1993,12(1):79-91

This paper reports a case study of atmospheric stability effect on dimethyl sulfide(DMS) concentration in the air. Investigation includes model simulation and field measurements over the Pacific Ocean. DMS concentration in surface sea water and in the air were measured during a research cruise from Hawaii to Tahiti. The diurnal variation of air temperature over the sea surface differed from the diurnal cycle of sea surface temperature because of the high heat capacity of sea water. The diurnal cycle of average DMS concentration in the air was studied in relation to the atmospheric stability parameter and surface heat flux. All these parameters had minima at noon and maxima in the early morning. The correlation coefficient of the air DMS concentration with wind speed (at 15 m high) was 0. 64. The observed concentrations of DMS in the equatorial marine surface layer and their diurnal variability agree well with model simulations. The simulated results indicate that the amplitude of the cycle and the mean  相似文献   

浙江燕山期主要Cu（mo）矿化岩体的地球化学特征   总被引：2，自引：0，他引：2  

胡永和  朱兴盛  徐有浪 《岩石矿物学杂志》1995,14(1):36-46

本文系统研究了浙江省燕山期主要Ｃｕ（Ｍｏ）矿化岩体的稀土、微量元素和稳定同位素地球化学特征。Ｃｕ（Ｍｏ）矿化岩体多属轻稀土富集型，一类铕异常不明显，多为矽卡岩型等矿床的成矿母岩；另一类负铕异常强烈，多为直接含矿斑岩体。Ｃｕ（Ｍｏ）矿化岩体多为Ｉ型，属火山弧和同造山碰撞形成。  相似文献   

大气边界层重力流与局地强降水的关系   总被引：2，自引：0，他引：2  

朱翠娟  李兴生 《大气科学》1982,6(1):58-64

本文利用测雨雷达、325米气象专用塔以及常规气象资料,分析了北京锋面暴雨产生前后的边界层结构。指出:随着锋面过境,低层出现了重力流的多次浪涌,每次浪涌前沿有强上升运动,最大可达35厘米/秒,每次重力流浪涌都伴有一阵强降水。重力流可以激发出周期为几分钟至20分钟的重力内波。  相似文献   

行星边界层中多极值风速廓线的研究   总被引：3，自引：0，他引：3  

李兴生  朱翠娟  刘林勤 《大气科学》1982,6(3):308-314

本文利用325米气象塔及声雷达探测资料分析了夜间平稳天气条件下行星边界层中风速出现多极值的现象。分析指出,多极值风速与边界层中多层逆温有密切的联系,当温度场出现多层逆温并维持一定的强度和时间后,便相应地出现了多层风速极大,风速极大值出现的高度在逆温顶附近或稍高。 文内还用一维非定常模式模拟了多极值风速廓线的形成。  相似文献