吉林中部石炭系岩石建造及其构造环境

吉林中部石炭系出露较全，具有独特的区域大地构造环境，在吉林晚古生代褶皱带演化中具有特殊性。本文将吉中石炭系划分为６个岩石建造，每一建造各具特征，并以岩石建造为手段，进行区域大地构造分析，认为该区石灰纪是在弧后一大陆边缘基础上形成的裂谷一拗陷带的构造环境，具有由先期裂谷发展阶段转变为末期拗陷带的演化过程，从而表明该区石炭纪为一拉张的构造历史时期。     

层序地层研究方法概论

层序地层学的理论思想被认为是地层学和沉积学中最伟大的革命。从九十年代以来,其概念体系已日臻完善并在全球范围内得到广泛使用。本文根据作者在新一轮１∶５万区域地质调查工作中的体会和经验,对层序地层学的研究方法作一简要介绍。其内容包括：层序地层学的理论基础,野外和室内的基本工作方法,层序地层单位与其它地层单位的关系,以及几点重要的注意事项等     

Precious Fossil-Bearing Beds of the Lower Cretaceous Jiufotang Formation in Western Liaoning Province, China

Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil bird-and reptile-bearing beds of the formation in the Dachengzi, Chaoyang, Dapingfang-Meileyingzi and Fuxin-Yixian basins. Among them, the precious fossil-bearing beds in the Dachengzi Basin may be recognized as the Xidagou Bed of the second member and the Yangcaogoudonggou Bed of the third member; those in the Chaoyang Basin may be confirmed as the Shangheshou Bed of the second member and the Dongpochi Bed of the third member; those in the Dapingfang-Meileyingzi Basin are as the Lamagou Bed of the second member, the Huanghuagou Bed of the lower third member and the Yuanjiawa Bed of the upper third member; and those in the Fuxin-Yixian Basin are listed as the Tuanshanzi Bed of the second member and the Pijiagou Bed of the third member. Since these basins are distinctly separated and the bird and reptile fossils are mostly new genera and species, we have to use the associated fossil ostracod assemblages as index to correlate the Xidagou Bed with the Shangheshou Bed and the Lamagou Bed, and to correlate the Yuanjiawa Bed with the Yangcaogoudonggou Bed and the Pijiagou Bed. Primarily, we established the sequence of the precious fossil-bearing beds of the Jiufotang Formation in western Liaoning. They are represented by, in ascending order, the Xidagou Bed of the second member, the Huanghuagou Bed of the lower third member, and the Yuanjiawa Bed of the upper third member. Obviously, this work has significance for the study on the time-space distribution and radiation of birds and dinosaurs during the period of the middle Early Cretaceous.     

Division and correlation of Yixian Formation in western Liaoning,China

The Yixian Formation is a series of volcanic-sedimentary rocks in Biepiao area of Liaoning Province.It is mainly composed of basic and intermediate-basic volcanic lava,pyroclasts and terrestrial sedimentary rocks.Based on the regularity of volcanic activity,the Yixian Formation was divided by the present authors into four members in ascending order:the first member is of basal conglomerate,basic and intermediate-basic volcanic rocks;the second member is of lake phrase sedimentary rocks,or in another word,precious fossil-rich sedimentary beds;the third is of basic volcanic rocks;and the fourth is of upper conglomerate.Field mapping and comprehensive study also indicate that there are abundant vertebrate fossils (mainly of Psittacosaurus) in the first member of the Yixian Formation,and the Jehol Biota (including Sinosauropterxy,Confuciusorns sanctus,Archaefructus,etc.) is yielded in the second member of Yixian Formation.From west to east,the volcanic activity of Yixian Formation changed regularly from early to late,and from basic and intermediate-basic to acid (alkali).     

辽西北票地区义县组古气候环境标志及其意义

野外地质调查及综合研究表明，包含中华龙鸟、被子植物等珍稀化石的热河生物群的主要赋存层位为义县组二段湖相沉积岩层。对产于不同地点沉积层中的植物、孢粉化石以及木化石进行了总结研究，分析了它们所反映的古气候环境，认为义县组沉积时期存在大量的喜温湿植物，总体指示温暖湿润的生存环境。同时，一些旱生的买麻藤类植物的普遍存在、本内苏铁类的膜质叶以及松柏类的鳞状叶等的特征反映了存在季节性干旱、半干旱气候的可能性。这种气候状况的出现可能与火山活动有关。     

Assessment of Snow Depth over Arctic Sea Ice in CMIP6 Models Using Satellite Data

Snow depth over sea ice is an essential variable for understanding the Arctic energy budget.In this study,we evaluate snow depth over Arctic sea ice during 1993-2014 simulated by 31 models from phase 6 of the Coupled Model Intercomparison Project(CMIP6)against recent satellite retrievals.The CMIP6 models capture some aspects of the observed snow depth climatology and variability.The observed variability lies in the middle of the models’simulations.All the models show negative trends of snow depth during 1993-2014.However,substantial spatiotemporal discrepancies are identified.Compared to the observation,most models have late seasonal maximum snow depth(by two months),remarkably thinner snow for the seasonal minimum,an incorrect transition from the growth to decay period,and a greatly underestimated interannual variability and thinning trend of snow depth over areas with frequent occurrence of multi-year sea ice.Most models are unable to reproduce the observed snow depth gradient from the Canadian Arctic to the outer areas and the largest thinning rate in the central Arctic.Future projections suggest that snow depth in the Arctic will continue to decrease from 2015 to 2099.Under the SSP5-8.5 scenario,the Arctic will be almost snow-free during the summer and fall and the accumulation of snow starts from January.Further investigation into the possible causes of the issues for the simulated snow depth by some models based on the same family of models suggests that resolution,the inclusion of a hightop atmospheric model,and biogeochemistry processes are important factors for snow depth simulation.     

智慧城市快速建设背景下的老旧社区智慧化改造探讨

我国城镇化在持续高速发展数十年后,城市系统慢慢形成了规模庞大的老旧社区。老旧社区总体智慧化水平较低,与居民智慧便捷的生活需求相矛盾。因此亟须一些合理的方案提升老旧社区的智慧化水平,从而更好地服务于社区居民,进一步推动城市的智慧化建设与发展。本文以广州市三眼井社区为例,介绍了老旧社区智慧化改造的关键技术,如CIM、5G、云计算、人工智能技术等,提出了切实可行的老旧社区改造建设方案,包括社区服务、智慧安防、智能基础设施、公共信息安全、智能居家养老等,为智慧城市建设中的老旧社区智慧化改造提供了有价值的参考。     

辽宁太子河流域晚元古宙青白口系震积岩的发现及其意义

介绍了辽宁太子河流域新发现的晚元古宙青白口系南芬组震积岩的层序。该层序为原地系统震积岩,由液化泥晶脉、震褶岩、震塌岩及地裂缝等组成。这是目前在我国所发现的最低层位碳酸盐岩振动液化地震事件记录。     

Experimental investigation of the strain rate effect on crack initiation and crack damage thresholds of hard rock under quasi-static compression

Acta Geotechnica - The crack closure stress σcc, crack initiation stress σci and crack damage stress σcd are important mechanical parameters to describe the brittle failure mechanism...