土体与时间相关的－维应力－应变性状、弹粘塑性模型和团结分析（续）

土体与时间相关的－维应力－应变性状、弹粘塑性模型和团结分析（续）殷建华ＪａｃｋＩ．Ｃｌａｒｋ（加拿大纽芬兰纪念大学冷海资源中心）７ＥＶＰ模型参数的确定在假说Ａ中，太沙基因结理论被用来计算团结中超孔隙水压力和压缩，次团结系数被用来估计次团结中的蠕变压缩...     

神华碳封存示范项目中CO2注入分布模拟

CO2咸水层封存被广泛认为是一种具有大规模温室气体减排潜力的地学前缘技术。选取中国第一个全流程CCS项目为研究背景,结合工程实际情况,选取鄂尔多斯盆地为具体研究对象,提取相关参数,建立相应的地质模型,通过数值模拟研究咸水层多层统注时CO2在咸水中的主要封存机制、CO2在地层中的运移分布特征及其与注入能力的关系,并观测由于CO2注入引起的地层压力、CO2摩尔分数、酸碱度等的变化情况,为方案的进一步优化奠定基础。研究表明,CO2注入咸水层后,大部分进入储层上部,且注入能力越大时,注入的层位越多,注入量越大;CO2在咸水层中的存在形式有自由态、束缚态和溶解态。所有探索性研究的目的是给示范性项目的未来提供一个良好的基础优化方案。     

Water resource development and protection in loess areas of the world: a summary to the thematic issue of water in loess

Loess is mainly distributed in arid and semiarid areas of the world, and water is essential and precious in the loess areas. Water is also an important factor inducing various geohazards and soil erosion in the loess areas. The thematic issue of Environmental Earth Sciences was edited to reflect the latest research on water and water-related themes in the loess areas of the world, especially on the Chinese Loess Plateau. This editorial introduced the background and initiative of editing this thematic issue, and it also introduced briefly the water environment projects currently underway on the Chinese Loess Plateau such as the grain for green project, the huge land creation project, and the sponge city project. The papers included in the thematic issue were also introduced to give readers a general understanding of their main research points. Finally, some suggestions to boost further water environment research in the loess areas were put forward. All the papers included in the thematic issue will scientifically support the sustainable socio-economic development in the loess areas of the world.     

中国与地质学有较密切关系的“世界学术期刊影响力指数(WAJCI)” Q1、Q2期刊

正中国科学文献计量评价研究中心、《中国学术期刊(光盘版)》电子杂志社有限公司、清华大学图书馆联合研发的《世界学术期刊影响力指数WAJCI年报》继2018年12月首发后,近日发布了2019年年报(WAJCI=World academic journals clout index)。在坚持用引用频次这一文献计量学方法对期刊进行客观评价的基础上,对世界学术期刊评价进行了以下方法改进,实现了1429种中国学术期刊与11659种海外学术期刊"的同台竞技"。     

CO2驱提高煤层气开采效果注入参数的实验研究

煤基CO₂地质封存是温室气体减排的重要方式,但也存在地下CO₂泄露的安全风险。为了评估煤基CO₂地质封存的安全性,采集沁水盆地南部胡底矿3号煤顶板泥质粉砂岩样品,模拟实验研究“CO₂-H₂O-岩”反应中柱状试样人工裂缝形貌、全岩矿物组成与CO₂导流能力变化。结果表明：方解石脉溶蚀、次生矿物充填与外部有效应力共同影响试样裂缝导流能力。原始渗透率为0.016×10^–3μm²的低渗试样,方解石脉溶蚀导致实验前期渗透率升高;随着反应进行,有效应力主导下裂缝闭合,渗透率呈“先升后降”变化趋势;原始渗透率为3.785×10^–3μm²的高渗试样,H₂CO₃不断溶蚀裂缝壁面长石等矿物,并产生高岭石等次生矿物混合充填于裂缝中,使渗透率持续降低。煤基CO₂地质封存过程中,较高的注入压力导致顶板产生人工裂缝;CO₂注入施工结束后,次生矿物充填及有效应力增大使裂缝导流能力快速下降,因此,煤中封存CO₂沿顶板裂缝长期泄露的风险较低。     

地质封存CO2水岩作用对页岩有机碳的萃取效应研究

CO₂ 水岩相互作用实验研究对于CO₂地质封存以及页岩气开发都具有重要意义。近年来多数研究主要侧重于岩石中矿物成分的反应过程,对于岩石中有机质成分的研究比较有限。本文选取盖层页岩,重点研究CO₂对于页岩中有机碳的萃取效应作用。实验使用高压反应釜在95 ℃和15 MPa条件下进行CO₂ 水页岩反应,同时考查不同的水岩接触方式对反应的影响,实验中分别测试了反应后水体中的溶解性有机碳(DOC)和反应前后岩石表面形态变化(SEM表征)。DOC的测试结果表明,相对于空白对照组高压N₂作用,超临界CO₂体系对于岩石有机碳具有明显的萃取效果,其中在不含水和仅含少量水的体系中,CO₂体系对DOC的萃取量能达到N₂体系的3倍以上,显示超临界CO₂极强的萃取能力。对比不同含水量的实验体系,发现含有少量水的情况下,CO₂对于有机碳的萃取量达到最大,比不含水的体系高出了87%,而这种能力的提高是由于少量极性分子H₂O的加入,能够增强超临界CO₂流体的溶剂化性能导致的。SEM结果也说明了不同的水岩气接触方式对岩石表面形貌具有不同的改造效果。本文实验结果有助于更好认识CO₂地质封存水岩作用及其潜在环境风险。     

A sensitivity analysis of factors affecting in geologic CO2 storage in the Ordos Basin and its contribution to carbon neutrality

To accelerate the achievement of China’s carbon neutrality goal and to study the factors affecting the geologic CO₂ storage in the Ordos Basin, China’s National Key R&D Programs propose to select the Chang 6 oil reservoir of the Yanchang Formation in the Ordos Basin as the target reservoir to conduct the geologic carbon capture and storage (CCS) of 100000 t per year. By applying the basic theories of disciplines such as seepage mechanics, multiphase fluid mechanics, and computational fluid mechanics and quantifying the amounts of CO₂ captured in gas and dissolved forms, this study investigated the effects of seven factors that influence the CO₂ storage capacity of reservoirs, namely reservoir porosity, horizontal permeability, temperature, formation stress, the ratio of vertical to horizontal permeability, capillary pressure, and residual gas saturation. The results show that the sensitivity of the factors affecting the gas capture capacity of CO₂ decreases in the order of formation stress, temperature, residual gas saturation, horizontal permeability, and porosity. Meanwhile, the sensitivity of the factors affecting the dissolution capture capacity of CO₂ decreases in the order of formation stress, residual gas saturation, temperature, horizontal permeability, and porosity. The sensitivity of the influencing factors can serve as the basis for carrying out a reasonable assessment of sites for future CO₂ storage areas and for optimizing the design of existing CO₂ storage areas. The sensitivity analysis of the influencing factors will provide basic data and technical support for implementing geologic CO₂ storage and will assist in improving geologic CO₂ storage technologies to achieve China’s carbon neutralization goal.©2022 China Geology Editorial Office.     

Development of world production and trade up to the year 2000 — A third world view

Conclusion The implications of this prospect for trade and international transportation are clear. If developing countries are to transform their economy and build up internal capacity for continued self-sustained growth, they will be able to do this only within certain restraints. These are likely to involve a certain decrease either in absolute or relative terms of their participation in world trade and their contribution to international transportation. Such a period of lessening trade will, however, be temporary and will last only whilst the economy is being transformed. Once this phase is passed, a new basis would have been laid for engaging in mutually beneficial international trade instead of the present one-sided exercise in self-flagellation.     

A field study of nitrogen storage and nitrate reductase activity in the estuarine macroalgaeEnteromorpha lingulata (Chlorophyceae) andGelidium pusillum (Rhodophyceae)

The purpose of this field study was to determine the relationship between environmental conditions, particularly high nitrate (NO ₃ ⁻ ), low salinity events, and both nitrogen (N) storage (NO ₃ ⁻ , ammonium [NH ₄ ⁺ ], free amino acids [FAA], protein, and total N) and nitrate reductase (NR) activity in the macroalgaeEnteromorpha lingulata andGelidium pusillum in the lower Mobile Bay estuary (Alabama, USA). The environmental conditions at the collection site varied over the growing season with the most notable changes due to late winter and spring runoff entering the estuary (1–30 psu, 0.3–25.8 μM NO ₃ ⁻ , 0.9–12.5 μM NH ₄ ⁺ , 3–28°C, 61–2,375 μmol PAR m⁻² s⁻¹). Principal component analysis reduced the six environmental variables measured to three principal components. Stepwise, multiple regression analysis was then used to examine the relationship between the principal components and the internal NO ₃ ⁻ , NH ₄ ⁺ , and FAA pools and NR activity. The results indicate that changes in inorganic N availability and salinity rather than changes in irradiance determine patterns of N storage and NO ₃ ⁻ reduction. BothE. lingulata andG. pusillum are capable of taking up and storing NO ₃ ⁻ when it becomes available. Greater NO ₃ ⁻ availability produced larger NH ₄ ⁺ and FAA pools along with higher rates of NR activity inE. lingulata, but notG. pusillum, suggesting thatE. lingulata is able to metabolize NO ₃ ⁻ more rapidly during high NO ₃ ⁻ , low salinity events. Differences in the susceptibility ofE. lingulata andG. pusillum to NH ₄ ⁺ inhibition and salinity stress combined with their different growth strategies help to explain the seasonal trends in total N. Total N inE. lingulata ranged from 2.57% to 6.39% dw, while the slower growingG. pusillum showed no significant variation in total N content (3.8–4.1% dw). These results led to the conclusion thatE. lingulata responds more quickly thanG. pusillum to high NO ₃ ⁻ , low salinity events and that these events have a larger effect on the overall N content ofE. lingulata.