松辽盆地东缘域地壳结构及其地质意义:深反射地震

松辽盆地东缘域位于松嫩—张广才岭微板块东部.自晚古生代以来该域经历了西拉木伦河缝合带闭合产生的北向挤压作用、蒙古—鄂霍茨克洋自西向东剪刀叉式闭合对其东侧东南侧产生的挤压作用以及西太平洋板块西向变向俯冲产生的挤压作用等区域构造应力场影响,从而产生了复杂的地壳变动.该东缘域的地壳结构与松辽盆地地壳是否具有相近的结构特点,这是至今未被研究的内容.在Songliao Drep研究中已经用深反射地震手段得到松辽盆地地壳结构的一组新认识.这些认识在其东缘域是否还成立,也需要用同样精度的手段予以研究.另外,莫霍界面的宏观特征与微观（内部）特征,从松辽盆地到其东缘域有什么样的变化,其形成机理是什么,也需要进一步研究.为了回答这些科学问题,从哈尔滨西至尚志市附近实施了一条东西向约150 km长的深反射地震剖面.通过研究发现东缘域与松辽盆地基底地壳具有明显的差别,即由松辽盆地地壳的三分性变到东缘域盆地外地壳的二分性,在剖面近东端得到近26 km深的莫霍界面深度,并用均衡理论分析莫霍界面形态特征的形成机理;上部地壳存在双向大型推覆断裂,推测其被推覆体主体是古亚洲洋沉积地层即C-P系海相地层.这些认识为中国东北地区探查晚古生代海相地层、研究东北亚地壳结构特征提供了理论依据.     

盐湖相低熟油脂肪酸的组成与分布特征

对泌阳凹陷碱性盐湖相、舞阳凹陷盐湖相、襄城凹陷膏盐湖相、南阳凹陷淡水湖相低熟油脂肪酸组成和分布特征进行了分析与研究。结果表明这些不同盐湖相的低熟原油的脂肪酸为丰度不同的饱和正构酸、不饱和正构酸、少量异构酸、类异戊二烯酸及脂肪酸乙酯系列化合物。脂肪酸的组成和分布反映了原始有机质的来源。     

Present recharge of an aquifer in a semi-arid region: an example from the Turonian limestones of the Errachidia basin, Morocco

 The Errachidia basin is composed of three superposed aquifers (Senonian, Turonian limestones and Infracenomanian). The Liassic limestone of the upper Atlas borders the northern part of the basin. The piezometric map of the Turonian aquifer displays a north-south flow, with an inflow area from the Atlas. This recharge hypothesis is demontrated by a discriminant analysis performed on chemical data: the majority of the spots are of sodium choride and hydrogenocarbonate types, while several boreholes are assigned to a calcium hydrogenocarbonate type Jurassic component. ¹⁸O measurements, using the Atlasic gradient δ¹⁸O=–4.18–0.0027 x elevation to estimate the recharge areas, confirm that the recharge area is the basin itself (<1100 m) on the Turonian outcrops, while in the confined part, the Turonian is recharged higher than 1400 m (corresponding to the Atlas). This contribution ranges from 56 to 85%, according to the situation versus the piezometric inflow area. The remainder represents infiltration and vertical leakage from the Senonian layers.     

A two-stage time series model for monthly hydrological projections under climate change in the Lim River basin (southeast Europe)

ABSTRACT

Climate change projections of precipitation and temperature suggest that Serbia could be one of the most affected regions in southeastern Europe. To prepare adaptation measures, the impact of climate changes on water resources needs to be assessed. Pilot research is carried out for the Lim River basin, in southeastern Europe, to predict monthly flows under different climate scenarios. For estimation of future water availability, an alternative approach of developing a deterministic-stochastic time series model is chosen. The proposed two-stage time series model consists of several components: trend, long-term periodicity, seasonality and the stochastic component. The latter is based on a transfer function model with two input variables, precipitation and temperature, as climatic drivers. The Nash-Sutcliffe model efficiency for the observed period 1950–2012 is 0.829. The model is applied for the long-term hydrological prediction under the representative concentration pathway (RCP) emissions scenarios for the future time frame 2013–2070.     

Comparing performance indicators to characterize the water supply to the demands of the Guadiana River basin (Spain)

ABSTRACT

Water indicators and indices are useful tools to assess river basin performance, that is, to measure whether the basin operates satisfactorily under a wide range of possible future demands and hydrological conditions. Spanish regulations assess the performance of water demands by using reliability indicators (RIs), established by law in 2008. This article raises the possibility of updating RIs by comparing them with sustainability indicators (SIs). SIs are widely used for the assessment of river basin performance and several policy scenarios. We applied a water allocation model to the Guadiana River basin in Spain to compare indicators under three scenarios. The study was framed within the science of socio-hydrology, combining the physical environment of a water system with its influence on social aspects. SIs gave better results than RIs when comparing future scenarios. We also propose the introduction of a vulnerability indicator into Spanish regulations.     

石羊河流域干旱气候对ENSO事件的响应及预测分析

根据石羊河流域5个气象站1961—2018年的降水、气温、干旱实况资料,利用气候统计学方法分析ENSO事件对该区气候变化及干旱的影响。结果表明:厄尔尼诺事件会造成流域春季降水偏多,春、秋、冬季气温偏高,易出现暖冬;拉尼娜事件则春季降水偏少,秋季降水偏多,冬季气温偏低,易出现冷冬,中下游发生中度以上春旱、春末夏初旱和伏旱的概率较高。应用1968—2010年旬、月气象要素和大气环流特征量,采用最优子集回归方法,建立降水和干旱统计预测模式,然后结合ENSO事件,通过加权平均法构建集成预测概念模型。对模型进行检验,拟合率与准确率较高,已投入业务使用。     

Analysis of the influence of Taihu Lake and the urban heat islands on the local circulation in the Yangtze Delta

The influences of human activities on regional climate and weather are tremendous. The re-gional temperature and the distributing of wind field are influenced, whereas the precipitation in-tensity and the spatial and temporal distribution of the precipita…     

Natural gas generation model and its response in accumulated fluids in the Yinggehai basin

The generation of natural gases is much more complicated in comparison with liquid petro-leum in that natural gases could be generated from both humic and sapropelic organic matter at different stages and that natural gases could be organic and inorganic …     

龙门山前陆褶皱冲断带构造解析与川西前陆盆地的发育

通过详细的野外地质调查和精细的地震剖面构造解析。揭示了龙门山前陆褶皱冲断带的基本构造特征。对比分析了龙门山北段与南段构造变形几何学和运动学的差异。提出龙门山北段主要表现为一系列复杂的逆冲推覆构造,晚三叠纪变形强于新生代;龙门山南段则以基底卷入的叠瓦状冲断为特点,晚白垩纪-早第三纪变形尤为突出。与前陆褶皱冲断带相对应的是,川西晚三叠纪时期的周缘前陆盆地主要表现在整个龙门山褶皱冲断带的前渊地区;而晚白垩纪-早第三纪再生前陆盆地却局限在川西盆地的南部,并且印-藏碰撞的持续挤压作用使得晚新生代构造变形不断向东扩展进入川西盆地南部。