泾河中游全新世古洪水沉积学与水文学研究(英文)

Palaeo-hydrological field investigation was carried out in the middle reaches of the Jinghe River. A set of palaeoflood slackwater deposit beds was identified in the Holocene loess-soil sequence in the riverbanks. The sediment samples were collected from the profile, and the particle-size distribution, magnetic susceptibility, loss-on-ignition were analyzed in laboratory. The analytical results showed that the palaeoflood slackwater deposits have re-corded extraordinary flood events in the Jinghe River valley. According to stratigraphic cor-relation and OSL dating, the palaeoflood events were dated to 4100-4000 a BP. The pa-laeoflood peak discharges were estimated to be 19,410-22,280 m3/s by using the hydro-logical model and checked by different approaches. These results have the flood data se-quence of the Jinghe River extended to 10,000-year time-scale. It provided significant data for hydraulic engineering and for mitigation of flood hazards in the Jinghe River drainage basin.     

Decoupling and decomposing analysis of construction industry’s energy consumption in China

Natural Hazards - The construction industry is one of the key industries for driving energy conservation in China. Decoupling of the construction industry development from energy consumption has...     

新疆阿克陶玛尔坎苏锰成矿带地质特征及成矿条件分析

玛尔坎苏锰成矿带沿玛尔坎苏河上游分布,东西延伸超过40 km。该成矿带以石炭系细碎屑岩-碳酸盐岩沉积建造为主,属典型的海相沉积型锰矿。锰矿带含矿层位稳定,矿体厚度大(最厚30.61 m),品位富(平均品位24%～35%,最高68.5%),矿石矿物以菱锰矿为主,属于低铁中磷类型。综合分析认为玛尔坎苏锰成矿带形成于滨浅海环境,成锰期处于一种安静、还原的水体环境。锰质来源以深源物质为主,与火山活动、热水活动关系密切。     

准噶尔盆地陆梁地区水化学特征与油气运聚

陆梁地区内水文环境从深部到浅部有明显变化,发育多向型水化学剖面。深部为较高矿化度的CaCl₂ 型地层水,浅层为较低矿化度的CaCl₂ 型地层水,中层发育低—高矿化度的NaHCO₃型水。地层水的这种剖面分布形式与深层逆断裂和中 浅部的正断裂有着密切的关系。据此将研究区划分为 3个水文地质旋回,每个旋回有着不同的水化学特征及发育不同的水化学剖面。研究区的水动力场与油气运聚关系十分密切,早期主要流向是西北至东南及西南至东北方向,中-晚期主要流向是西南至东北方向,与油气运移方向基本一致。     

中国煤炭地震勘探技术发展

我国煤炭地震勘探技术的发展有着近50年的历史。从无到有,从使用光点仪、模拟仪、数字仪到无线遥测仪;从折射到反射,从单次覆盖到多次覆盖;从二维到三维;从单波到多波。经过几代人的不断努力,逐步形成了中国特色的煤炭地震勘探技术体系,整体技术达到国际先进水平。煤炭地震勘探技术的应用,为我国煤炭工业的发展作出了巨大的贡献。在中国煤炭地质总局成立50周年之际,回顾我国煤炭地震勘探在不同历史时期对煤炭地质勘探的作用和贡献,提出当前地震勘探面临的新课题,展望前景,为我国煤炭能源生产提供地质保障,将具有十分重要的意义。     

陕西省国有地勘单位改革发展刍议

党的十八届三中全会作出了全面深化改革的战略部署,国有地勘单位改革也随之进入攻坚期、深水区。如何借鉴经验教训,深化国有地勘单位改革,这值得深思。陕西省国有地勘单位在全国率先统一由事业单位改制为国有企业,在国有地勘单位改革中形成了"陕西模式"。本文概述了陕西省国有地勘单位改革发展历程,分析了在改革主导、管理体制、运行机制和变革途径等方面呈现的改革特点,梳理了在构建现代企业架构、激发市场化经营思维、拓宽服务领域、增强地勘企业经济效益和建实省级公益性地勘队伍等方面取得的改革成效。文章认为,当前市场环境、现有顶层设计以及自身发展基础等均不利于改制后的国有地勘单位发展壮大,国有地勘单位企业化改革的"陕西模式"面临升级。     

Phytoplankton community dynamics during Alexandrium blooms in 2019 off the Qinhuangdao coast,Bohai Sea,China

Journal of Oceanology and Limnology - Alexandrium blooms in the northwest area of the Bohai Sea (Qinhuangdao coastal area), China, produce large amounts of toxins that could be enriched in...     

三峡库区典型滑坡地质与地球物理电性特征

滑坡属于地质灾害中的重要灾种之一,查明滑坡区的地质与地球物理特征,对分析滑坡形成机制、评价滑坡稳定性具有重要意义。鉴于此,本文将高密度电法引入三峡库区腹地万州区滑坡地质调查中,在区内四方碑滑坡、塘角1号滑坡和麻柳林滑坡进行地球物理探测工作,并结合钻孔资料对实测结果进行对比验证。实测结果表明：在地形复杂地区开展地球物理探测工作,通过数据反演与分析,可获取滑坡体地层结构及滑移面;结合相关地质资料,通过对比解译,可弥补单纯依靠钻孔信息来确定滑移面形态的不足;3个典型滑坡区地球物理实测资料揭露滑坡体和滑床地球物理电性特征表现为,由崩坡积物、第四系粉质黏土以及含水碎石块组成的滑坡体电阻率低于40 Ω·m,而由砂岩与泥岩组成的滑床电阻率高于40 Ω·m,高密度电法对基岩滑坡和土质滑坡都能获取较好的结果。     

Variations in melt supply along an orthogonal supersegment of the Southwest Indian Ridge(16°–25°E)

The orthogonal supersegment of the ultraslow-spreading Southwest Indian Ridge at 16°–25°E is characterized by significant along-axis variations of mantle potential temperature. A detailed analysis of multibeam bathymetry,gravity, and magnetic data were performed to investigate its variations in magma supply and crustal accretion process. The results revealed distinct across-axis variations of magma supply. Specifically, the regionally averaged crustal thickness reduced systematically from around 7 Ma to the present, indicating a regionally decreasing magma supply. The crustal structure is asymmetric in regional scale between the conjugate ridge flanks, with the faster-spreading southern flank showing thinner crust and greater degree of tectonic extension. Geodynamic models of mantle melting suggested that the observed variations in axial crustal thickness and major element geochemistry can be adequately explained by an eastward decrease in mantle potential temperature of about40°C beneath the ridge axis. In this work, a synthesized model was proposed to explain the axial variations of magma supply and ridge segmentation stabilities. The existence of large ridge-axis offsets may play important roles in controlling melt supply. Several large ridge-axis offsets in the eastern section(21°–25°E) caused sustained along-axis focusing of magma supply at the centers of eastern ridge segments, enabling quasi-stable segmentation. In contrast, the western section(16°–21°E), which lacks large ridge-axis offsets, is associated with unstable segmentation patterns.     

Study of Effects of Hard Thick Roof on Gas Migration and Field Experiment of Roof Artificially Guided Pre-splitting for Efficient Gas Control

Due to high gas content, high geo-stress and complex geological conditions, gas disasters occur frequently in deep coal mining. The hard thick roof (HTR) greatly increases the difficulty of coalbed gas control besides causing dynamic disasters. In this paper, the effects of HTR on gas migration were numerically analyzed based on a multi-field coupling model. Results indicated that the hanging arch leads to remarkable stress concentration and induces a “cap-shaped” low-permeable zone above the gob, which greatly prevents gas from migrating upwards. Meanwhile, HTR hinders the subsidence movements of the upper rock strata, contributing to very few roof fractures and bed-separated fractures. Without the formation of roof-fractured zone, coalbed gas completely loses the possibility of upward concentration and will accumulate in the gob, forming a major safety hazard. To overcome these problems, borehole artificially guided pre-splitting (BAGP) technology was proposed. Three different pre-splitting boreholes were constructed as a group to generate artificial fractures in advance in HTR via deep-hole blasting, promoting the evolution of roof fractures. With the effects of mining stress, a fracture network is eventually formed in HTR, which provides a preferential passage for the upward flow of coalbed gas. Moreover, the controllable breaking of HTR was achieved and the roof strata could deform and subside regularly, forming an “O-shaped” roof-fractured zone above the gob which greatly improves the gas extraction efficiency of roof high-level boreholes. In addition, after BAGP, several extraction measures can be applied in the gob-side entry to drain the gas in different concentrated areas. In the field experiment, the roof periodic breaking length was reduced by half, and the average gas extraction rate was increased by 4 times to 67.7%. The synergetic controls of HTR and coalbed gas were effectively realized. This study provides valuable insight into gas control in other deep coal mines with similar geological conditions.