龙永煤田童子岩组顶部鲕粒的矿物学特征及岩相意义

通过对龙永煤田童子岩组煤系顶部鲕状带"鲕粒"赋存规律及其矿物学特征、宏观特征、围岩特征的野外研究及镜下观察,分析了"鲕粒"的成因及其岩相意义,为龙永煤田童子岩组顶部地层提供了对比依据.     

Release of heavy metals during weathering of the Lower Cambrian Black Shales in western Hunan,China

Weathering of heavy metal enriched black shales may be one of the most important sources of environmental contamination in areas where black shales are distributed. Heavy metal release during weathering of the Lower Cambrian Black Shales (LCBS) in western Hunan, China, was investigated using traditional geochemical methods and the ICP-MS analytical technique. Concentrations of 16 heavy metals, 8 trace elements and P were measured for samples from selected weathering profiles at the Taiping vanadium ore mine (TP), the Matian phosphorous ore mine (MT), and Taojiang stone-coal mine (TJ). The results show that the bedrock at these three profiles is enriched with Sc, V, Cr, Co, Ni, Cu, Zn, Pb, Th, U, Mo, Cd, Sb, Tl, and P. Based on mass-balance calculation, the percentages of heavy metals released (in % loss) relative to immobile element Nb were estimated. The results show significant rates of release during weathering of: V, Cr, Co, Ni, Cu, Zn, U, Mo, Cd, Sn, Sb, and Tl for the TP profile; Sc, Cr, Mn, Co, Ni, Cu, Zn, Pb, Th, Cd, and Sn for the MT profile; and Sc, Mn, Co, Ni, Zn, Th, Cd, Sn, and Tl for the TJ profile. Among these heavy metals, Co, Ni, Zn, Cd, and Sn show very similar features of release from each of the three weathering profiles. The heavy metals released during weathering may affect the environment (especially topsoil and surface waters) and are possibly related to an observed high incidence of endemic diseases in the area.     

Formation of an Interactive User-Oriented Forecasting System: Experience from Hydrological Application in Linyi, Eastern China

Having provided an overview of the ideas of developing user-oriented interactive forecast system (UIFS) emerging in recent years,the authors proposed an idealized framework of the new-generation meteorological system,which includes the initial user-end module for configuring the forecast target,the physical predictive and downscaling components,and an incessant assessing module in association with decision-making at the user-end.A case study was carried out with a focus on applying the TIGGE (THORPEX Interactive Grand Global Ensemble;THORPEX stands for The Observing System Research and Predictability Experiment) precipitation forecasts for the hydrological users in Linyi,a region richest in rivers and reservoirs in eastern China.The preliminary results exhibited great potential of improvement in applications of weather forecasts by combining the user-end information.Although the TIGGE results provided by existing national/international operating models were independent from the user-end,the case study enlightened ways of establishing an iteratively self-improving UIFS involving user-orientation throughout the forecast process.     

Modeling of Solar Wind in the Coronal Funnel with Mass and Energy Supplied at 5 Mm

The origin of the solar wind is a long-standing issue in both observational and theoretical studies. To understand how and where in the solar atmosphere the mass and energy of the solar wind are supplied is very important. Previous observation suggests a scenario in which the fast solar wind originates at heights above 5 Mm in the magnetically open funnel, a process that is accompanied by downward flow below 5 Mm, whereby the mass and energy are supplied through reconnection between the open funnel and adjacent closed loops. Based on this scenario, we develop a fluid model to study the solar wind generation under the assumption that mass and energy are deposited in the open funnel at 5 Mm. The mass supply rate is estimated from the mass loss rate as given by the emptying of the side loops as a result of their assumed reconnection with the open funnel. Similarly, the energy input rate is consistent with the energy release rate as estimated from the energy flux associated with the reconnection between the open magnetic funnel and the closed magnetic loops. Following the observations, we not only simulate the plasma flowing upward to form the solar wind but also calculate the downward flow back to the lower atmosphere. This model is a first attempt to study physically the proposed scenario of solar wind origin and gives a new physical illustration of the possible initial deposition and consequent transportation of mass and energy in the coronal funnel.     

福建三明地区萤石矿地质特征及成矿预测

三明地区位于闽西北隆起带与闽西南坳陷带接合部,萤石矿资源丰富,其成矿受常口一瀚仙一余朋北东向断裂构造带控制。总结该断裂构造带地质条件．阐述已知萤石矿点基本特征及找矿标志,通过成矿预测,提出了清流余朋等五个成矿重点区．宜作为今后工作的重点。     

东天山白山钼矿地球化学特征及地质意义

白山钼矿赋矿岩体为花岗斑岩,其主量、微量及稀土元素地球化学特征研究表明,岩体属过铝质高钾钙碱性系列,并相对富集大离子亲石元素(Rb,Th,Sr等),亏损高场强元素(Nb,Ce,Zr等),以及具有LREE富集的右倾稀土元素分布模式。根据矿物稀土元素作为示踪剂提供的信息表明,含钼矿物的石英脉稀土元素组成和分布模式与壳幔同熔型花岗岩有众多相似之处,推测该成矿物质来源与花岗岩岩浆有关,来自同一源区,形成于碰撞后演化阶段向板内转化的构造环境,并具相同的成岩方式与成岩成矿同期。     

Centrifuge modelling of ground-borne vibrations induced by railway traffic in underground tunnels

Increased attention has been given to ground-borne vibrations induced by railway vehicles and to the effects of these vibrations as they propagate through the g...     

1979～2020年北极和青藏高原臭氧低值区的动力输送特征比较

基于ERA5月平均再分析资料,利用Lorenz环流分解方法从定常和瞬变以及基流和涡旋的角度对比了北极与青藏高原臭氧低值区的动力输送特征。结果表明：动力总输送在两地上平流层作用最强,均使其臭氧浓度降低,且定常输送均强于瞬变输送,纬向与经向输送的作用均大致相反。然而,动力输送在北极地区的作用强度远大于青藏高原地区。北极地区纬向输送使得平流层中上层臭氧浓度降低,平流层下层臭氧浓度升高,经向输送的作用与之相反且强度明显偏弱,二者均主要作用于上平流层。青藏高原地区纬向和经向输送除在上平流层均使得臭氧浓度降低外,二者作用大致相反且强度相当,输送大值区在垂直方向上存在双中心结构,分别位于上平流层与上对流层—下平流层（Upper Troposphere–Lower Stratosphere,简称UTLS）区。两地区纬向和经向输送的差异均主要由定常涡旋输送所造成。青藏高原地区定常与瞬变输送的强度差异没有北极地区大。此外,两地定常和瞬变输送中涡旋对臭氧纬向平均的输送均起到主要作用,体现出涡旋输送在两地臭氧浓度变化的动力输送过程中发挥着至关重要的作用。     

地质环境信息系统上线安全检测工作实践

本文针对地质环境领域业务系统的特点,提出了一种信息系统上线安全检测的方法,深入探讨了上线安全检测实践中的基本流程、测评方法与测评成果,为提升地质环境信息系统安全运行和服务能力提供了技术支撑.     

Solar Wind and Chromospheric Network

A physical model of the transition region, including upflow of the plasma in magnetic field funnels that are open to the overlying corona, is presented. A numerical study of the effects of Alfvén waves on the heating and acceleration of the nascent solar wind originating in the chromospheric network is carried out within the framework of a two-fluid model for the plasma. It is shown that waves with reasonable amplitudes can, through their pressure gradient together with the thermal pressure gradient, cause a substantial initial acceleration of the wind (on scales of a few Mm) to locally supersonic flows in the rapidly expanding magnetic field trunks of the transition region network. The concurrent proton heating is due to the energy supplied by cyclotron damping of the high-frequency Alfvén waves, which are assumed to be created through small-scale magnetic activity. The wave energy flux of the model is given as a condition at the upper chromosphere boundary, located above the thin layer where the first ionization of hydrogen takes place.Among the new numerical results are the following: Alfvén waves with an assumed f ^-1 power spectrum in the frequency range from 1 to ⁴ Hz, and with an integrated mean amplitude ranging between 25 and 75 km s⁴, can produce very fast acceleration and also heating through wave dissipation. This can heat the lower corona to a temperature of 5× 10⁵ K at a height of h=12,000 km, starting from 5× 10⁴ K at h=3000 km. The resulting thermal and wave pressure gradients can accelerate the wind to speeds of up to 150 km s^-1 at h=12,000 km, starting from 20 km s^-1 at h=3000 km in a rapidly diverging flux tube. Thus the nascent solar wind becomes supersonic at heights well below the classical Parker-Type sonic point. This is a consequence of the fact that any large wave-energy flux, if it is to be conducted through the expanding funnel to the corona, implies the building-up of an associated wave-pressure gradient. Because of the diverging field geometry, this might lead to a strong initial acceleration of the flow. There is a multiplicity of solutions, depending mainly on the coronal pressure. Here we discuss two new (as compared with a static transition region model) possibilities, namely that either the flow remains supersonic or slows down abruptly by shock formation, which then yields substantial coronal heating up to the canonical 10⁶ K for the proton temperature.