赞比亚东北部班韦乌卢地块泛非期以来构造演化的裂变径迹约束

本文利用锆石和磷灰石裂变径迹方法探讨了班韦乌卢地块泛非期以来的主要构造演化时间。为研究班韦乌卢地块的构造活动,本文从班韦乌卢地块中部卡帕图地区的沉积盖层姆波罗科索群的姆巴拉组、萨马组和卡布韦卢马组中采集多件新鲜的岩石样品,并获得5件锆石和2件磷灰石样品裂变径迹分析结果。5件锆石裂变径迹年龄介于575±35～380±22 Ma之间,其峰值年龄组为600～572 Ma和420～390 Ma。2件磷灰石裂变径迹年龄介于59±6～27±4 Ma之间,其峰值年龄组为99～80 Ma和19～11 Ma。它们的峰值年龄组分别对应的主要时代为新元古代的埃迪卡拉纪、早泥盆世、晚白垩世和中新世。对比区域上已有的年龄数据可知,南部非洲地区新元古代的埃迪卡拉纪、早泥盆世和晚白垩世的构造活动是一个区域性的构造事件,仅中新世(19～11 Ma)的构造活动在区域上的表现尚不明确。综合前人成果资料,自泛非构造运动以来,班韦乌卢地块至少经历600～572 Ma、488～441 Ma、420～390 Ma、375～293 Ma、99～80 Ma及19～11 Ma六个构造事件。班韦乌卢地块泛非期以来的构造演化研究程度很低,...     

Cenozoic thermal history reconstruction of the Dongpu Sag,Bohai Bay Basin: Insights from apatite fission‐track thermochronology

Knowledge of the thermal history of the onshore Dongpu Sag (DPS), Bohai Bay Basin is important for understanding its tectonic development within a broader regional context and for elucidating its poorly studied source‐rock maturation history. To unravel DPS time‐temperature development, apatite fission‐track data were acquired from eight sandstone samples in three deep wells. Thermal history modelling indicates continuous heating during the rifting stage (early Eocene to late Oligocene), followed by cooling attributed to tectonic uplift between ~27 and ~16 Ma, which resulted in the removal of ~1,400 to 1,800 m of section. Reheating occurred during the subsidence stage from middle Miocene until present. Unlike typical passive continental margin basins, the DPS experienced accelerated post‐rifting subsidence from ~5.8 Ma, which was especially marked since ~2.6 Ma. This phase was probably triggered by normal fault reactivation, in combination with a variation in the deep heat flow pattern.     

Measurement of Martian atmospheric winds by the O2 1.27 μm airglow observations using Doppler Michelson Interferometry: A concept study

Science China Earth Sciences - China’s Mars exploration mission has stimulated tremendous interest in planetary science exploration recently. To propose potential scientific research...     

Response of runoff to climate change in the Wei River basin,China

Abstract

Climate change will likely have severe effects on water shortages, flood disasters and the deterioration of aquatic systems. In this study, the hydrological response to climate change was assessed in the Wei River basin (WRB), China. The statistical downscaling method (SDSM) was used to downscale regional climate change scenarios on the basis of the outputs of three general circulation models (GCMs) and two emissions scenarios. Driven by these scenarios, the Soil and Water Assessment Tool (SWAT) was set up, calibrated and validated to assess the impact of climate change on hydrological processes of the WRB. The results showed that the average annual runoff in the periods 2046–2065 and 2081–2100 would increase by 12.4% and 45%, respectively, relative to the baseline period 1961–2008. Low flows would be much lower, while high flows would be much higher, which means there would be more extreme events of droughts and floods. The results exhibited consistency in the spatial distribution of runoff change under most scenarios, with decreased runoff in the upstream regions, and increases in the mid- and lower reaches of the WRB.

Editor Z.W. Kundzewicz; Associate editor D. Yang     

Spatial microsimulation modeling for residential energy demand of England in an uncertain future

High quality infrastructure is crucial to economic success and the sustainability of society. Infrastructures for services, such as transport, energy, and water supply, also have long lead times, and therefore require effective long-term planning. In this paper, we report on work undertaken as part of the UK Infrastructure Transitions Research Consortium to construct long-term models of demographic change which can help to inform infrastructure planning for transport, energy, and water as well as IT and waste. A set of demographic microsimulation models (MSM), which are spatially disaggregate to the geography of UK Local Authorities, provides a high level of detail for understanding the drivers of changing patterns of demand. However, although robust forecasting models are required to support projections based on the notion of ‘predict-and-provide,’ the potential for behavioral adaptation is also an important consideration in this context. In this paper, we therefore establish a framework for linkage of a MSM of household composition, with behavior relating to the consumption of energy. We will investigate variations in household energy consumption within and between different household groups. An appropriate range of household types will be defined through the application of decision trees to consumption data from a detailed survey produced by the UK Department of Energy and Climate Change. From this, analysis conclusions will be drawn about the impact of changing demographics at both household and individual level, and about the potential effect of behavioral adjustments for different household groups.     

Variation Characteristics of Mercury in Speciation during Road Runoff for Different Rainfall Patterns

Mercury (Hg) concentration was investigated during 2010 based on road runoff from Nanjing Ring Highway, China. The emphasis was placed on impact of rainfall characteristics on Hg speciation concentration, and on variation characteristics of Hg speciation during road runoff for different rainfall patterns. Results indicated that average concentration of total mercury (THg) was in the range from 0.472 to 1.304 µg/L, and steady Hg (SHg) was the dominant form of Hg. Rainfall and average rainfall intensity were two important factors of determining Hg speciation concentrations during road runoff for different rainfall patterns. Rainfall pattern had significantly influence on variation of available Hg and dissolved Hg during road runoff, and on their proportions in THg. However, the proportion of SHg in THg was not obviously affected by rainfall pattern. On the other hand, toxic degree of Hg to soil environment is various for different rainfall patterns, based on Hg speciation variation.     

HY-1C Coastal Zone Imager observations of the suspended sediment content distribution details in the sea area near Hong Kong-Zhuhai-Macao Bridge in China

The impacts of the Hong Kong-Zhuhai-Macao Bridge (HKZMB) on suspended sediment content (SSC) were analysed in the Zhujiang River Estuary based on data from HY-1C, which was launched in September 2018 in China, carrying Coastal Zone Imager (CZI) and Chinese Ocean Color and Temperature Scanner on it. A new SSC inversion model was established based on the relationship between in-situ SSC and the remote sensing reflectance in red and near-infrared bands of CZI image. HY-1C satellite data obtained from October to December 2019 were applied to retrieve SSC in the Zhujiang River Estuary. The results show that SSC around the HKZMB is ranging from 20 mg/L to 95 mg/L. SSC change obviously on two sides of the bridge. During flooding and ebbing period, SSC increases obviously downstream of the bridge. SSC difference between upstream and downstream is ranging from 5 mg/L to 20 mg/L. Currents flowing across the HKZMB, the change trend of SSC in most places upstream and downstream is almost the same that SSC downstream of the bridge is higher than SSC upstream. The tidal currents interact with bridge piers, inducing vortexes downstream, leading the sediment to re-suspend downstream of the bridge piers. Other factors, including seafloor topography and wind, can also contribute to the distribution of SSC in the Zhujiang River Estuary.     

黑龙江依兰煤田达连河组油页岩生物 标志化合物特征及地质意义

采用气相色谱、气相色谱-质谱技术开展了依兰煤田达连河组油页岩的生物标志化合物特征研究.饱和烃气相色谱显示,达连河组油页岩有机质具有混合来源.中部厚层油页岩样品奇偶优势(OEP)值普遍大于2.4,表明其成熟度相对较低,而煤层间厚层油页岩的OEP均小于2.4,表明随深度的增加其成熟度相对较高.中部厚层油页岩段样品的Pr/Ph值均大于0.8,含煤段油页岩样品的Pr/Ph值均大于2.8.综合分析认为,达连河组下部含煤段油页岩层有机质丰度高,水生低等生物对有机质贡献较大,有机质类型主要为Ⅱ1型,具有姥鲛烷优势,为弱氧化—弱还原、淡水湖沼相沉积;中部厚层油页岩段有机质类型主要为Ⅱ1型、Ⅱ2型,具有姥植均势,反映了淡水—微咸水深湖相环境.     

Leon Knopoff

莱昂·诺波夫（Leon Knopoff,1925-2011）是美国洛杉矶加州大学（UCLA）物理学和地球物理学教授、杰出的教育家,也是美国荣誉最高的3个学术团体的会员,即美国国家科学院、美国哲学学会和美国人文与科学学院（AAAS）.     

台风"莫拉克"暴雨特征

利用常规气象资料和卫星、雷达、区域自动站等资料以及NCEP再分析资料,对2009年闽东北地区"莫拉克"台风的降水特征做初步分析.结果表明:台风"莫拉克"暴雨具有明显的"空心化"特征,有利的环境场条件、螺旋雨带上对流单体的不断影响、台风移动缓慢是此次台风暴雨的主要原因,而地形也有明显增幅作用.通过雷达回波基本反射率因子强...