断层土壤氡观测方法的综合应用

为了对比有关土氡观测的稳定性及观测结果的映震能力,在原北川县政府断层气观测场地内建立了三组综合观测孔,进行ＲａＡ法,氡管仪法和α径迹蚀刻法测试实验。同时增加对地面空气中氡含量的测量,以便对比实验效果以确定几种方法的可信度。对连续１７个月三种方法的观测数据进行分析,测试的数据曲线同步性很好,年变规律清楚,观测资料与附近地震发生有较好的对应关系。     

山东省渤海沿岸湿地价值估算与保护对策

山东省渤海沿岸湿地价值估算的目的是提醒公众尤其是政府决策部门关注湿地的综合功能,而不是也不应该单纯向湿地索取,更不能破坏性地开发,需要科学保护和合理利用,以使湿地可持续利用。通过分析湿地动态影响因素,提出了湿地保护管理的对策措施。     

褶皱相关断层——以库车坳陷新生界盐上构造层为例

以盐构造解析的方法,综合地震与地质资料,表明库车坳陷新生界中的盐上断层受控于褶皱作用。盐上地层首先发生褶皱变形,随着褶皱作用的加强,然后发生断裂作用,盐上构造层的变形方式为褶皱相关断层,其变形特征不同于断层相关褶皱。从断层成因机制可见:断层相关褶皱理论不适用于库车新生代坳陷盐构造发育区。库车坳陷膏盐层的发育造成盐上构造层与盐下构造层变形有差异,盐上构造层以褶皱作用为主,盐下构造层以冲断作用为主。库车坳陷盐上构造层主要为褶皱相关断层,发育张性断块、后翼突破断层、前翼突破断层及褶皱相关断层组合等构造样式,根据盐上构造层的变形特征总结了褶皱相关断层的演化。     

山东省金桥煤矿塌陷地综合治理研究

通过对金桥煤矿开发利用方案的分析,结合煤层赋存特征,进行了塌陷地预测．并与首采区实际塌陷地对比分析了预测的可靠性。按照边开采边治理的原则,提出了首采区塌陷地综合治理方案,为恢复矿山环境提供了依据。     

The amalgamation of the supercontinent of North China Craton at the end of Neo-Archaean and its breakup during late Palaeoproterozoic and Meso-Proterozoic

The most important geological events in the formation and evolution of the North China Craton concentrate at two stages: 2 600–2 400 Ma and 2 000–1 700 ma (briefly, we call them 2.5 Ga event and 1.8 Ga event respectively in this paper). We propose that the essences of these two events are: Several Archaean micro-continents amalgamated to form one supercontinent according to the plate tectonic principle with a small scale at about 2.5 Ga, and the supercontinent broke down by upwelling of an ancient mantle plume at about 1.8 Ga.     

A new nonlinear risk assessment model based on an improved projection pursuit

Experience has shown that researchers and engineers are unable to construct ideal models for risk assessment and make optimal decisions in situations with insufficient data. A nonlinear risk assessment model is therefore proposed in this study based on an improved projection pursuit model (IPPM) for use in situations where insufficient data are available. A new projection index is initially proposed based on the maximum entropy principle in order to extract more information from original multidimensional data before a nonlinear risk assessment function is constructed using differential equation modeling. This function can be applied to all risk assessment problems after performing standardization and dimension reduction for the indicators. Five marine environmental risk assessment experiments for naval activity are then performed to train and validate the IPPM, as well as a traditional projection pursuit model using different numbers of training samples. The results of this analysis show that the IPPM is reliable, robust, and consistent, and can improve risk assessments by between 4.3 and 43.7% depending on performance criteria. Satisfactory results are obtained from the IPPM using just 12 training samples, and an acceptable result is still obtained if this number is reduced to just ten. Application of an IPPM therefore represents a valuable tool for risk assessment in situations where data is insufficient.     

Three-Year Observations of Ozone Columns over Polar Vortex Edge Area above West Antarctica

Ozone vertical column densities (VCDs) were retrieved by Zenith Scattered Light-Differential Optical Absorption Spectroscopy (ZSL-DOAS) from January 2017 to February 2020 over Fildes Peninsula, West Antarctica (62.22°S, 58.96°W). Each year, ozone VCDs started to decline around July with a comparable gradient around 1.4 Dobson Units (DU) per day, then dropped to their lowest levels in September and October, when ozone holes appeared (less than 220 DU). Daily mean values of retrieved ozone VCDs were compared with Ozone Monitoring Instrument (OMI) and Global Ozone Monitoring Experiment 2 (GOME-2) satellite observations and the Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2) reanalysis dataset, with correlation coefficients (R2) of 0.86, 0.94, and 0.90, respectively. To better understand the causes of ozone depletion, the retrieved ozone VCDs, temperature, and potential vorticity (PV) at certain altitudes were analyzed. The profiles of ozone and PV were positively correlated during their fluctuations, which indicates that the polar vortex has a strong influence on stratospheric ozone depletion during Antarctic spring. Located at the edge of polar vortex, the observed data will provide a basis for further analysis and prediction of the inter-annual variations of stratospheric ozone in the future.     

Genetic Type and Metallogenic Mechanism of Bankuan Gold Deposit in Special Reference to the Studies of Fluid Inclusions and Isotopes in Minerals

Auriferous quartz veins in the Bankuan gold deposit occur in the interlayer broken zone of the basal conglomerate of the Tietonggou Formation or at the unconformity between the Tietonggou Formation and the crystalline basement.The composition of fluid inclusions in the minerals indicates that the nature and composition of ore-forming hydrothermal solutions show a drastical change soon after the solutions reached the Tietonggou Formation from the crystalline basement,resulting in gold precipitation.So the Bankuan gold deposit can be assigned to the conglomerate stata-bound-type deposits.137 thermometric data are concentrated in the three ranges 400-340℃,330-220℃ and 180-160℃,representing three episodes of metalogenesis,Oxygen isotope studies demonstrate the evolution of ore-forming hydrothermal solutions from early metamorphic to late meteoric,Diversity of ore-forming materials dominated by deep-source material is supported by sulphur and lead isotope data.From the above discussions it may be concluded that the deposit formed by metamorphism induced as a result of Mesozoic northward intracontinental subduction along the Machaoying fault.     

龙泉关韧性剪切带地质特征

龙泉关韧性剪切带由五台期韧性剪切带和吕梁期韧性剪切带复合而成，五台期韧性剪切带形成于低角闪岩相环境下，吕梁期韧性剪切带形成于绿片岩相环境下。两期韧性剪切带对五台期和吕梁期变质建造具有明显的控制作用，并部分地改造了阜平期变质岩。     

熊耳群研究四十年

本文全面回顾四十年来熊耳群火山岩的研究历史综述前人成果,详细分析了现存在的问题,对于今后应着力开展的工作提出了一些看法,笔者认为,现有认识矛盾的关键问题是,熊耳群形成矢折的裂谷构造环境,为什么体现岛弧的地球化学特征（亏损高场强元素,富集大离子亲石元素和轻稀土元素）？今后熊群火山岩研究的重要问题有：鉴别岩浆源区性质和可能可经的过程,揭示其富钾并体同出岛弧型火山岩地球化学特征的原因,确定是否有冲带组分