许昌新区建设的理念及可持续发展规划

随着城市化的进程,城市可持续发展已经成为人们关注的热点问题。以可持续发展为系统目标,统筹考虑区域经济、社会、环境、资源等要素,通过构建城市新区经济—社会—生态系统,规划许昌新区。遵循以人为本、生态和谐、城乡统筹和可持续发展的理念,提出了公平和谐、产—城融合、田园生态、城乡统筹、林水一体、延续文脉的许昌新区可持续发展规划,推动许昌新区建设。     

基于脱钩模型的煤炭城市可持续发展动态分析——以徐州市为例

促进经济与环境协调是煤炭城市可持续发展的关键和核心。采用物质流分析、脱钩分析和分解分析等方法,深入分析了1995—2007年徐州市经济增长与资源环境之间的脱钩类型、可持续状态及驱动因素。结果表明:研究期内徐州市DMI和DPO的年均增长率分别为2.74%和0.91%,而GDP年均增长率为12.62%,二者之间呈较为明显的正相关关系,而物质代谢效率的提升又使其发展方式呈现向资源节约型、环境友好型发展模式转型的趋势;资源投入、废物排放与经济增长之间均出现弱脱钩现象,表明徐州经济系统正处于显著的弱可持续发展态势;经济规模扩大和技术效应抑制作用减弱是引起煤炭城市资源环境约束性增强、可持续发展降低的主要驱动因素。     

Geochronology and geochemistry of leucosomes in the North Dabie Terrane, East China: implication for post-UHPM crustal melting during exhumation

Migmatites are widespread in the North Dabie ultrahigh-pressure metamorphic terrane (NDT) of Dabie orogen, East China. Idiomorphic and poikilitic amphibole grains in both leucosome and melanosome contain inclusions of plagioclase, quartz and biotite, suggesting formation of leucosome by fluid-present melting of biotite + plagioclase + quartz-bearing protoliths at P = 5–7 kbar, T = 700–800 °C. Precise SIMS zircon U–Pb dating indicates that migmatization of Dabie orogen initiated at ~140 Ma and lasted for ~10 Ma, coeval with the formation of low-Mg^# adakitic intrusions in Dabie orogen. Based on mineralogical, petrographic and geochemical data, leucosomes in NDT can be subdivided into three groups. (1) High La/Yb_(N)–Medium Sr/Y group (Group I), whose high Dy/Yb_(N) but medium Sr/Y ratios are caused by amphibole and plagioclase residual during partial melting of dioritic to granodioritic gneisses. (2) Low La/Yb_(N)–Low Sr/Y group (Group II), whose flat HREE patterns are produced by entrainment of peritectic amphiboles into melts derived from partial melting of dioritic gneiss. (3) High La/Yb_(N)–High Sr/Y and Eu^# group (Group III), whose extremely high Sr and Eu but low other REE concentrations are caused by accumulation of plagioclase and quartz. Although Group I and III fall in the adakitic fields on La/Yb_(N)–Yb_(N) and Sr/Y–Y diagrams, they are chemically distinct from contemporary high-pressure adakitic intrusions in Dabie orogen in a series of geochemical indexes, for example, lower Dy/Yb_(N) and/or Sr/Y ratios at given La/Yb_(N) ratio, lower Sr/CaO ratios, lower Rb concentration but higher K/Rb ratios. Therefore, leucosomes are produced by anatexis of the exhumed ultrahigh-pressure metamorphic rocks at middle crustal level, instead of partial melting of thickened lower crust with garnet-rich and plagioclase-poor residual. The coeval occurrence of migmatites and high-pressure adakitic intrusions in Dabie orogen indicates large-scale partial melting of middle to thickened lower crustal column in the early Cretaceous. The required heat source may be the mantle heat conducting through the lithospheric mantle whose lower parts have been convectively removed.     

西藏班戈县东嘎花岗岩体特征及锡找矿前景分析

东嘎花岗岩体位于冈底斯一念青唐古拉板片北缘、班公错一怒江结合带中段班戈一崩错板片。岩体时代为燕山晚期,属印度一欧亚板块碰撞造山构造环境。岩石属富钠、硅铝过饱和类型,该岩体位于斑戈一嘉黎一波密一察隅锡成矿远景带内,岩浆分异程度高,具有S型花岗岩体的典型特征,与滇西、川西含锡花岗岩体特征相似,成矿条件有利。区域化探资料显示锡异常明显,异常为Sn、Rb、Y、u、Nb、Ag、w、Th、Pb等多元素组合。sn元素的强度高、规模大。据区域地质、岩石化学及地球化学特征及区域成矿资料,东嘎花岗岩体具有良好的锡成矿前景。     

柿庄南区块煤层气井早期生产特征及开采建议

从水文地质的角度揭示了不同情况下单井的排水采气机理。在此基础上结合柿庄南区块59口井的实际排采数据,综合分析了气水产量,井底流压,套压及动液面随时间的变化曲线;并将早期生产特征归纳为3种类型：①低产水-高产气型,见气早,产气量高（>1000 m3/d）、产量递减缓慢、峰值产量高,日产水量小（<2m3/d）,套压高;②低产水-中低产气型,日产气小于1000 m3,产量衰减明显且波动大,排水期较长;③高产水型,产气极少或无,日产水量大（>10m3/d）,动液面下降缓慢,套压很低或为零。最后针对不同类型的低产井,提出相应的开采建议：低产水-低产气型井可采用二次压裂措施,改善煤层渗透率;高产水井可通过无机堵水或加大排采强度等方式排采;煤层气井排采要勇于实践,探索适合该区不同煤层的成功排采方法。     

用多元回归分析从试井求得的平均渗透系数提取单层参数信息的方法

本文提供一种从试井求得的平均渗透系数回算每个单层渗透系数的方法。井的试验,无论是为供水、排水或工程建设目的的常规试井,还是为热田开发目的的专门性地热试井,其首要任务是确定含水层或热储层的各项参数,其中最主要者为地层的渗透系数K。     

The generation kinetics of natural gases in the Kela-2 gas field from the Kuqa Depression, Tarim Basin, northwestern China

The Kela-2 gas field, found in the Kuqa Depression of the Tarim Basin, northwestern China, is a large-sized dry gas field (C1 /C1-5 =0.992 0.999) and characterized by ultra-high pressure (pressure factor up to 2.0 2.2). The pyrolysis experiment was carried out under isothermal gold-tube closed system, with samples collected from the Jurassic coal, Jurassic mudstone and Triassic mudstone in the Kuqa Depression. The result of gas yield showed that the Middle and Lower Jurassic source rocks have higher gas generation potential than the Triassic source rocks. The kinetic modeling of gas generation and methane carbon isotope fractionation suggested that the Kela-2 gases belong to the products of high-over mature stages and were mainly derived from the Middle and Lower Jurassic coal-bearing strata. The Triassic source rocks made a minor contribution to the Kela-2 gases. The Kela-2 gases chiefly generated from coal-bearing source rocks with R o values from 1.3% to 2.5%, and thus primarily accumulated after 5 Ma.     

Advances of Soil Microbiology in the Last Decade in China

Soils are fundamental to preservation and sustainability of life-support system on Earth. Soils develop as the most dynamic and complex interface linking atmosphere, hydrosphere, lithosphere and biosphere. Soils harbor enormous diversities of microbial communities as the primary driving forces for global exchanges of matter and energy on our planet. Despite of its profound importance, the invisible soil microbes have for long been underappreciated. In the early 2000s, there has been growing awareness that soil microbiology has attracted huge interest from nonsoil scientists due to the introduction of three domain phylogeny. It is also known as tree of life theory which is widely recognized as the most accurate reflection of the relatedness of all organisms and provides us with a tool to classify and elucidate the largely untapped resource of soil microbial communities. In January 2005, the Department of Earth Sciences of National Natural Science Foundation of China organized a workshop of ‘Soil Biology and Soil Processes’ with focused discussion on soil microbiology research frontiers. The workshop outlined research priorities, cross disciplinary research opportunities, technological needs and potential breakthroughs within soil microbiology. This workshop has witnessed the rapid advances of soil microbiology in soil nutrient transformation, global environmental changes and environmental remediation over the last decade in China. This article will give a brief review on soil microbial researches in the past decade in China, present the status quo of funding system and highlight the challenge and opportunities for future soil microbiology in China.     

对流电场产生电离层扰动的典型事例

用欧空局ＥＩＳＣＡＴ极光区非相干散射雷达观测资料、南极中山站电离层垂测站和我国１２０°Ｅ电离层站链ｆ０Ｆ２资料，分析了１９９１年５月２～３日一次主要由磁层对流引起的电离层扰动过程。从形态特征上看，它与热层中性大气参与的动力耦合过程明显地不同。对照比较表明，这是一次典型的磁层－电离层电动耦合事例。全球地磁站网资料从另一侧面证实，本文讨论的耦合机制是正确的。     

Stratification and mixing of a post-glacial Neoproterozoic ocean: Evidence from carbon and sulfur isotopes in a cap dolostone from northwest China

To improve our knowledge about the geochemical and environmental aftermath of Neoproterozoic global glaciations, we analyzed stable isotopes (δ¹³C, δ¹⁸O, δ³⁴S) and elemental concentrations (Ca, Mg, S, Sr, Fe, and Mn) of the ～ 10-m-thick Zhamoketi cap dolostone atop the Tereeken diamictite in the Quruqtagh area, eastern Chinese Tianshan. Available chemostratigraphic data suggest that the Tereeken diamictite is probably equivalent to the Marinoan glaciation. Our new data indicate that organic and carbonate carbon isotopes of the Zhamoketi cap dolostone show little stratigraphic variations, averaging ? 28.2‰ and ? 4.6‰, respectively. In contrast, sulfur isotopes show significant stratigraphic variations. Carbonate associated sulfate (CAS) abundance decreases rapidly in the basal cap dolostone and δ³⁴S_CAS composition varies between + 9‰ and + 15‰ in the lower 2.5 m. In the overlying interval, CAS abundance remains low while δ³⁴S_CAS rises ～ 5‰ and varies more widely between + 10‰ and + 21‰. The range of δ³⁴S_py of the cap dolostone overlaps with that of δ³⁴S_CAS, but direct comparison shows that δ³⁴S_py is typically greater than δ³⁴S_CAS measured from the same samples. Hypotheses to explain the observations must account for both the remarkable sulfur isotope enrichment of pyrites and the inverse fractionation. We propose that CAS and pyrite were derived from two isotopically distinct reservoirs in a chemically stratified basin or a basin with a sulfate minimum zone. In this model, CAS was derived from shallow, oxic surface waters with moderate sulfate concentration and depleted in ³⁴S due to the post-glacial influx of sulfur from continental weathering. In contrast, pyrite was derived from anoxic bottom waters (or a sulfate minimum zone) with low sulfate concentration and ³⁴S enrichment due to long-term syn-glacial sulfate reduction. The rapid shift in CAS abundance and sulfur isotope composition within the cap dolostone is interpreted to reflect the mixing of the two reservoirs after initial deglaciation. Comparison with other post-Marinoan cap carbonates shows significant spatial heterogeneity in δ³⁴S_CAS, which together with strong temporal variation in δ³⁴S_CAS, points to generally low sulfate concentrations in post-Marinoan oceans.