甘孜-玉树断裂带的近代地震与未来地震趋势估计

通过对甘孜－玉树断裂带上近代地震的震级、震中位置和地震地表破裂的空间展布特征的研究，采用Ｎｉｓｈｅｎｋｏ和Ｂｕｌａｎｄ（１９８７）发展的“特征地震复发时间通用分布”概率模型，即“ＮＢ”模型，对甘孜－玉树断裂带各段落未来５０ａ内强震趋势进行了估计。根据研究结果识别出，未来５０ａ内本断裂带内马尼干戈断裂段具有强震复发的高危险性，当江断裂段强震复发的可能性也不能排除，这为地震中长期预报提供了重要依据     

Segmentation of Active Faults and Risk Probability Prediction of Strong Earthquakes in Sichuan Province

Based on geometric structure,active strength,and maximum seismic rupture length along the fault in the late Quaternary or Holocene,this paper presents the segmentation of main active faults in Sichuan Province and uses the recurrence probability model to predict the recurrence probabilities of strong earthquakes along each segment during next 30 years.The results indicate that earthquakes with M=7.0 or greater may happen along Qiajiao segment,Qianning segment,and Selaha segment of Xianshuihe fault zone,the segment from Xichang to Mianning and Yejidong segment of Anninghe fault zone; earthquakes with M=6.0 or greater may happen along the segment from Maowen to Caopuo of Longmenshan fault zone and Xiaoyanjing segment of Anninghe fault zone.     

四川大凉山断裂带的晚第四纪平均滑动速率

大凉山断裂带呈近南北向或北北西展布于安宁河、则木河断裂东侧的大凉山腹地，是一条连接鲜水河、小江断裂的贯通性全新世活动断裂，全长约280km。航、卫片解译及野外实地考察结果表明，大凉山断裂带由海棠-越西、普雄河、布拖及交际河四条次级断裂呈羽列组合而成，晚第四纪以来的平均左旋滑动速率在3mm／a左右。     

Slip Rate and Strong Earthquake Dislocation along the Moxi—Mianning Segment of the Xianshuihe Anighe Fault Zone

The results from interpretation of the aerophotos and in-situ seismogeological researches show that there are some obvious late-Quaternary activities along the Moxi-Mianning segment of the Xianshuihe-Anninghe fault zone, with the characteristics of sinistral-slip movement accompanied by some significant vertical slip components. Since late-Quaternary, the average horizontal slip rate of the segment at the south of Moxi along the Xianshuihe fault is 6.0～9.9mm/a and 4.7～5.3mm/a along the segment at the north of Mianning of the Anninghe fault. The results from the investigation of coseismic dislocation and ground rupture show that the ground rupture caused by 1876 Kangding-Luding earthquake with M 7 3/ 4 can extend to the south of Tianwan. The segment at the north of Mianning of the Anninghe fault has a background for producing M7.5 earthquake and the geological record of the last strong earthquake must be the proofs of the 1327 earthquake with M>6.0 with poor historical records.     

用Delphi进行直方图的组数选择与绘制

基于可视化程序设计思想,用BorlandDelphi4编程实现了直方图的组数选择与绘制。程序能够绘制出[5,25]区间内各组数的原始或对数数据频率分布直方图图形,从而使用户能够直观地根据图形选择合适的直方图分组。程序界面友好、使用方便。     

TECTONIC DEFORMATION AND STRONG EARTHQUAKE ACTIVITIES ON THE EAST BORDER OF TIBET PLATEAU

TECTONIC DEFORMATION AND STRONG EARTHQUAKE ACTIVITIES ON THE EAST BORDER OF TIBET PLATEAU     

Study on Active Faults and Seismogenic Structure for the 1989 Batang M6.2 ～ 6.7 Earthquake Swarm in the Litang-Batang Region of West Sichuan, China

INTRODUCTIONGeological investigations since the1970s have shown that the sub_longitudinal Jinshajiang andHonghe(Red River)fault zones constitutethe western boundary of“Rhombic Sichuan_Yunnan Block”onthe Sichuan_Tibet border and display mainly dextral sh…     

Experimental investigation on effect of curing stress on the strength of cement-stabilized clay at high water content

The application of cement-stabilized marine clay at high water content (HW-CSC) as land reclamation fill has been receiving increasing attention and popularity. In current coastal development, HW-CSC land reclamation projects begin to advance toward deeper water areas, leading to greater filling heights and thus higher curing stresses acting on the lower portions of HW-CSC. In principle the higher curing stress will improve the strength gain of HW-CSC, but this curing stress effect is not taken into account in current design practice. This study aims to bridge the gap. Fifteen different mixes of HW-CSC are first prepared and cured in consolidation tubes for seven days under various curing stresses. Their strengths and some other post-curing parameters are then tested and analyzed to demonstrate the quantitative effect of curing stress on the strength gain of HW-CSC. Results indicate that the strength gain of HW-CSC is significantly influenced by the curing stress; however, the effect of curing stress cannot be simply replaced by reducing the remolding water content during mixing stage and letting the specimens be cured under atmospheric stress condition. Therefore, it is concluded that the effect of curing stress includes two different components—a consolidation effect and another effect termed the “self-stress” effect in this study. Finally, an empirical relationship accounting for the combined effects of mixing proportion and curing stress is developed for characterization of the strengths of HW-CSCs with different mixing proportions and various curing stresses. The proposed relationship is validated by three independent data groups collected from the literature. This empirical relationship can be helpful in optimization of mixing proportions of HW-CSC used for land reclamation purpose.     

尖笔帽螺(Creseis acicula)研究进展及其在大亚湾暴发机制初探

尖笔帽螺(Creseis acicula)隶属软体动物门翼足目, 是营浮游生活的大洋暖水种, 在世界多个海域尤其是印度洋沿岸多次暴发, 但此前在中国海域未有暴发记录。2020年6—7月, 在大亚湾西南部核电站邻近海域监测到尖笔帽螺大规模暴发, 整个过程持续约1个月, 高峰期密度达到5600个·m^-3, 是迄今为止已报道的该种暴发的最高密度。尖笔帽螺的高密度区均集中在西南部沿岸区域, 尤其是岭澳核电站冷源取水口附近, 对核电冷源运行安全造成了严重影响, 引起政府、企业、科研界和社会公众的高度重视。鉴于目前对尖笔帽螺的暴发机制还知之甚少, 文章综述了尖笔帽螺生物生态学特征研究进展, 阐述了大亚湾尖笔帽螺的暴发和消退过程, 并基于对此次暴发事件的跟踪监测, 初步探讨其暴发机制及其生态效应, 认为核电站冷却水的温升效应、降雨引起的海水盐度波动以及浮游植物数量升高可能是诱发其暴发的重要因素。     

基于风险区划的农业干旱保险费率厘定——以河北省冬麦区为例

近年来,在气候变化和极端天气气候事件频发的背景下,干旱等农业气象灾害的频发已对我国尤其是河北省的粮食生产和农业发展的可持续性带来了严重威胁。选择或构建合适的农业干旱灾害风险指标开展干旱风险区划,并在此基础上进行灾害的保险费率厘定对于丰富农业保险模式,促进农业保险经营的稳定和发展具有重要的应用价值。本文基于作物水分亏缺率指数、降水距平百分率指数和抗旱指数等指标,构建干旱综合风险指数并开展风险区划研究;利用修正后的纯保险费率,得到适用于本研究区的保险费率厘定模型,探寻一种能较全面改善目前农业保险经营弊端的保险模式,从而实现冬小麦农业保险的持续健康发展。