中国天气发生器降水模拟参数的气候变化特征

利用中国672个站点1951-2007年的逐日降水资料,分1951-1978和1979-2007两个时段分析了中国天气发生器BCC/RCG-WG降水模拟参数的气候变化特征.结果表明,在气候变化背景条件下,我国各地干日到湿日的降水转移概率P(WD)和湿日到湿日的降水转移概率P(WW)除了西部部分地区有增大的趋势外,其余大部地区均有减小的趋势.相对于P(WW),全国各地P(WD)的减小幅度更大.日降水量GAMMA分布形态参数ALPHA除西北地区西部部分地区有减小趋势外,其余大部地区略有增大趋势,尺度参数BETA在全国各地基本都保持增大的趋势,其中西北地区西部等地增大趋势尤为明显.相对于BETA的变化幅度,ALPHA的减小幅度较小,基本在6%以内.     

Quantitative Gas-in-place Comparison of Original and Bitumen-free Lacustrine Shale

Residual bitumen in organic-rich shale of oil windows exists widely, and its effect on the gas storage capacity of shale could be two-fold. Bitumen could occupy and block the nanopores of shale, thereby reducing the gas storage capacity. On the other hand, gas could be dissolved in bitumen in shale gas reservoirs, leading to enhanced gas storage capacity. To quantify the effect of bitumen on the gas-in-place (GIP) estimation of lacustrine organic-rich shale, the micropore characteristics and methane sorption capacity of original and bitumen-free shale from the Triassic Yangchang Formation of the Ordos Basin, combined with the methane dissolution capacity for the isolated bitumen, were analyzed and compared. GIP for the original and bitumen-free shale in the depth range of 500–2500 m was evaluated. The results show that micropores in the shale samples were mainly related to organic matter. Clay mineral-hosted pores contributed slightly to microporosity. Bitumen significantly reduced the micropore surface area and volume of the original shale, with average percentages of 28.09% and 51.26%, respectively. The methane sorption capacity decreased after bitumen removal. When normalized to the original shale mass, the sum of the methane sorption capacity for bitumen-free shale and the methane dissolution capacity for isolated bitumen was similar to the methane sorption capacity of the original shale, indicating that the lack of methane absorbed on bitumen is the main reason for the decrease in methane sorption capacity after bitumen removal. The contribution of absorbed methane on bitumen to sorbed methane in shale could be higher than 36.23%. Dual effects of bitumen on shale GIP were observed. A high content of bitumen (1.12%) increased the GIP of the shale samples, with an average percentage of 23.5% in the depth range of 500–2500 m, while a low content of bitumen (0.06%) decreased the GIP, with an average percentage of 13.6%.     

中国天气发生器的降水模拟

A stochastic model for daily precipitation simulation in China was developed based on the framework of a ‘Richardson-type‘ weather generator that is an important tool in studying impacts of weather/climate on a variety of systems including ecosystem and risk assessment. The purpose of this work is to develop a weather generator for applications in China. The focus is on precipitation simulation since determination of other weather variables such as temperature is dependent on precipitation simulation. A framework of first order Markov Chain with Gamma Distribution for daily precipitation is adopted in this work. Based on this framework, four parameters of precipitation simulation for each month at 672 stations all over China were determined using daily precipitation data from 1961 to 2000. Compared with previous works, our estimation for the parameters was made for more stations and longer observations, which makes the weather generator more applicable and reliable. Spatial distributions of the four parameters are analyzed in a regional climate context. The seasonal variations of these parameters at five stations representing regional differences are discussed.Based on the estimated monthly parameters at 672 stations, daily precipitations for any period can be simulated. A 30-year simulation was made and compared with observations during 1971-2000 in terms of annual and monthly statistics. The results are satisfactory, which demonstrates the usefulness of the weather generator.     

中国近海北部陆架海相地层解体问题的研究

晚更新世以来,中国近海北部陆架近岸地区至少发生了三次海侵并保留三期海相地层.在研究了数千千米的浅地层剖面仪测量资料及大量钻孔资料后,笔者发现最后冰期最盛时期陆架出露,海相地层并非简单地、原封不动地被保留下来.在强大的风力作用下,除进行正常的风成沉积以外,还产生了沉积分异作用,出现风暴沉积及其衍生沉积,裸露的陆架至少部分地改变了原来的沉积结构,形成了新的沉积类型,构成复杂的混杂堆积区和黄土堆积区.这样,原先的海相地层被破坏,或者部分被保留下来,即陆架上海相地层发生了解体.     

Wave shoaling and diffraction in current over a mild-slope

The wave relative frequency in the coordinate system moving with current and the angle between the direction of wave propagation and that of current are computed based on the wave dispersion relation. The current field is computed by solving the depth averaged shallow water equations. The wave field is computed by solving the mildslope equation which has taken the current‘s effect into account. A numerical model is established using a finite element method for simulating the wave shoaling and diffraction in current over a mild-slope, and the numerical results are reasonable to compare with the experimental data.     

湖北省震情速报微信公众平台

在“互联网+”大背景下,利用微信公众平台接口技术和第三方代码托管技术,设计湖北省震情速报微信公众平台。该系统对EQIM数据库时时监听,产出权威地震信息;实现地震查询、科普宣传等功能,为地震工作者和普通大众提供交互平台;地震自救、灾情上报等功能可为防震减灾工作带来便利。     

河南伏牛山金矿成矿流体性质及找矿意义

伏牛山东麓主要发育中低温热液型和构造蚀变岩型金矿,矿床分布受区域剪切带控制。两类金矿床各自赋存的围岩不同,且其流体包裹体中的盐度、密度、Na⁺/K⁺比值及氢、氧同位素组成显示出较大的差异,表明围岩及成矿流体性质对成矿起联合控制作用。根据包裹体同位素分析,推测成矿物质来源于变质水且有岩浆水和雨水的混入。结合单矿物电子探针测定结果,计算了围岩成岩、变质及成矿的温度、压力和沉淀条件。同时确定了富CO₂包裹体的泡腾包裹体群、液相成分的高硫富HCO₃^-、气相成分中高CO₂及CO₂/H₂O比值等特点是寻找此类金矿床的重要包裹体标志。     

南华北东部徐淮地区新元古界生烃潜力分析

通过地层特征、有机地球化学指标和岩相古地理的分析,研究了南华北东部(徐淮地区)新元古界作为烃源岩及形成原生油气藏的可能性.结果表明:徐淮地区新元古界有机质丰度低,母质类型为Ⅰ型干酪根,热演化程度处于成熟—过成熟阶段;自下而上可划分为青白口系刘老碑组和南华系贾园组—魏集组两套烃源岩,后者又细分为贾园组—九顶山组和张渠组—...     

Subduction of the Bangong–Nujiang Ocean: constraints from granites in the Bangong Co area,Tibet

We report geochronologic, whole‐rock geochemical and Sr–Nd isotopic analyses of the granites that are exposed to both the north and the inside of the Bangong–Nujiang Suture (BNS) zone as well as the implications for the Mesozoic history of Tibet. To the north of the BNS, the Larelaxin pluton consists of I‐type quartz diorite and highly fractionated I‐type biotite granite. The Larelaxin pluton is enriched in large‐ion lithophile elements (LILE) but depleted in high‐field‐strength elements (HFSE); therefore, it exhibits the features of volcanic arc rocks. The initial Sr (0.7102 to 0.7215) and negative εNd (t) (−2.91 to −5.20) values imply a mixture of depleted mantle and continental crust. The mean ²⁰⁶Pb/²³⁸U zircon age is 168 Ma; we therefore propose that the Bangong–Nujiang Ocean (BNO) had already been subducted beneath the Qiangtang terrain by the middle Jurassic. Inside the BNS, the Rutog granites intruded into the Lagongtang and Duoren formations, which show a continental margin and a forearc basin sedimentary facies, respectively. The mean ²⁰⁶Pb/²³⁸U zircon age is 101 Ma. The Rutog granites are monzogranites with a high Na/K ratio (Na₂O/K₂O > 1) and a high LILE/HFSE ratio, and A/CNK < 1.1. The high Sr/Y ratio (22 to 56) implies that these granites are adakitic. The low initial Sr (0.7044 to 0.7055) and positive εNd (t) (+1.46 to +2.70) values indicate that the protolith of the Rutog granites originated mainly from a depleted source. We attribute the Rutog plutonism to the development of an oceanic arc during the continuing northward subduction of the BNO and propose that the Rutog adakitic granites were formed by melting of the subducted BNO crust with limited crustal contamination. Copyright © 2013 John Wiley & Sons, Ltd.     

构造叠加晕找盲矿法及其在矿山深部找矿效果

构造叠加晕找盲矿法是在发展了原生晕找盲矿理论基础上,根据热液矿床成矿成晕严格受构造控制,热液矿床具有多期多阶段叠加成矿成晕特点,提出原生晕叠加理论,解决了困惑化探专家几十年在研究原生晕轴向分带中出现的"反常"现象难题,独创了构造叠加晕找盲矿新方法,并介绍了构造叠加晕方法特点、主要成果、金矿床4种叠加结构的理想模式和盲矿预测的5条准则,应用效果和找矿实例。