黄河三角洲地区地热资源及其开发利用前景初析

黄河三角洲地区蕴含着丰富的中低温地热,为2000m以浅经济型地热资源,经计算,全区地热资源总量折合标准煤相当于125×10~8t,其中仅地下热水总储存量就达到4570×10~8 m~3,可开采储量超过750×10~8 m~3,至少可以开采100a。如果形成以东营、河口、孤岛、广饶为中心的4个大面积系统的开发利用体系,并注重地热资源的综合利用和梯级利用,对于缓解能源紧张、促进经济的可持续发展等方面具有重要的意义。     

The radial structure of hot one-temperature accretion flows with advection

Considering nonthermal e^±-pair production, this paper is focused on the radial structure of hot one-temperature accretion flows with advection under the condition of small viscous parameter ( = 0.1) and low mass-accretion rates. Self-similar relations of hot flow with advection have been adopted. The authors have used a scheme, in which the two regions of accretion flow are calculated separately and then joined together. Some typical features of hot flow with advection have been confirmed, and several new results obtained: there exists a critical radius r_cr; the local cooling rate is inversely proportional to the square of the mass of the central object; the e^±-pair process affects significantly the radiation of hot flows with advection.     

Are Arc Basalts Dry, Wet, or Both? Evidence from the Sumisu Caldera Volcano, Izu-Bonin Arc, Japan

Basalt–basaltic andesite (<55 wt % SiO₂) and dacite–rhyolite(66–74 wt % SiO₂) are the predominant eruptive productsin the Sumisu caldera volcano, Izu–Bonin arc, Japan. Themost magnesian basalt (8·5% MgO), as well as some ofthe other basalts, has a low Zr content (20–25 ppm), andcannot yield basalts with higher Zr contents (29–40 ppm)through fractionation and/or assimilation. The high- and low-Zrbasalts have different phenocryst assemblages, olivine, plagioclaseand pyroxene phenocryst chemistries, REE (rare earth element)patterns, and fluid-mobile element/immobile element ratios.Estimated primary olivine compositions are more magnesian (>Fo₉₁)in the low-Zr basalts compared with those in high-Zr basalts(<Fo₈₉). The low-Zr basalts contain up to 11 vol. % augite,but many high-Zr basalts are free of augite, which appears onlyin their more differentiated products. The low-Zr basalts areconsidered to be hydrous magmas in which olivine crystallizesfirst followed by augite and plagioclase, whereas the high-Zrbasalts are dry. The low-Zr basalts have higher U/Th ratiosthan the high-Zr basalts. We suggest that both dry and wet primarybasalts existed in the Sumisu magmatic system, each having differenttrace element concentrations, mineral assemblages and mineralchemistry. The lower contents of Zr and light REE and magnesianprimary olivines in the wet basalts could have resulted froma higher degree of partial melting (20%) of a hydrous sourcemantle compared with 10% melting of a dry source mantle. TheSr, Nd and Pb isotope compositions of the wet and dry basaltsare similar and are limited in range. These lines of evidenceindicate that a mantle diapir model might be applicable to satisfythe configuration of such a mantle source region beneath a singlevolcanic system such as Sumisu. KEY WORDS: degree of melting; hot fingers; isotopes; mantle diapir; mantle wedge     

Possible Impact of the Summer North Atlantic Oscillation on Extreme Hot Events in China

This paper reveals that the summer North Atlantic Oscillation (SNAO) is closely related to the extreme hot event (EHE) variability in China during the period of 1979 2009, with a positive-phase (negative-phase) SNAO corresponding to less (more) EHEs in northern China. The summer circulation anomalies associated with the SNAO give further confirmation of the above relationship. In a positive-phase (negative-phase) SNAO year, there is an anomalous cyclone (anticyclone) over central East Asia, which can increase (decrease) the total cloud cover over this region. Such changes of the total cloud cover can then decrease (increase) the solar radiation reaching the surface, which is consequently unfavorable (favorable) to the formation of EHEs over northern China.     

四川的地热水资源

四川的地热水资源丰富，大多数热水出露于构造断裂带和洒谷地区，主要储集在三叠纪地层中的碳酸盐岩里。根据温（热）泉的分布状况、热水的类型和物理化学特征，对地热田进行了预测分区。     

Abiotic versus biotic controls on the development of the Fairmont Hot Springs carbonate deposit, British Columbia, Canada

The relict Fairmont Hot Springs deposit, formed largely of carbonates, covers an area of 0·5 km², and is up to 16 m thick. The triangle‐shaped discharge apron, which broadens down‐valley, is divided into a proximal part with beds dipping at <10° and a distal part with beds dipping at 10° to 15°. The deposit is formed of the: (1) Basal Macrophyte; (2) Lower Carbonate; (3) Middle Clastic; (4) Upper Carbonate; and (5) Upper Clastic Sequences. Two charcoal samples embedded in the Lower Carbonate Sequence yielded dates of 8690 ± 90 and 8270 ± 70 cal yr bp , indicating that much of the deposit formed post‐glacially during the Early to Mid‐Holocene. Deposit aggradation ceased in the Mid to Late Holocene when the Fairmont Creek valley was incised. The Lower and Upper Carbonate Sequences, which are the thickest sequences, are composed of nearly equal parts of travertine (abiotic) and tufa (biotic), with feather dendrite travertine, radiating dendrite travertine and stromatolite tufa dominating. Competition between calcite precipitation rates and biotic growth rates controlled the distribution of tufa and travertine across the discharge apron. Calcite and biotic growth rates were controlled largely by flow velocity across the apron which, in turn, was controlled by topography and regular fluctuations in spring water discharge volume. During times of high spring discharge, slow sheet flow over the proximal part of the apron promoted stromatolite growth, whereas fast, turbulent flow on the distal part of the apron induced rapid feather dendrite formation. During times of low spring discharge, quiescent, shallow evaporative pools, conducive to radiating dendrite formation, formed on the proximal part of the apron, whereas slow flow on the distal part promoted stromatolite growth. Facies with high calcite supersaturation experienced rapid abiotic dendrite growth that precluded most biotic growth.     

固定铝log(Q/K)图解在温泉中的应用

为探讨常规和固定铝log(Q/K)图解法对温泉系统是否有效 ,采用WATCH程序 ,对江西 3个温度较高的温泉 ,即庐山温泉、汤湖温泉和横泾温泉 ,进行了探测性的研究 .采用常规log(Q/K)图解法计算时 ,由于参加计算的 4个水样的铝含量均未检出 ,计算结果显示只有不含铝的矿物玉髓和方解石相交于温度 1 0 0℃附近 ,热储总体上没有达到平衡 .在采用了固定铝log(Q/K)图解法并同时考虑冷水的稀释作用计算后 ,中低温地热系统中常见的蚀变矿物如浊沸石、纤蛇纹石、萤石和玉髓均显示了较好的收敛性 ,收敛的温度大致在 1 0 0～ 1 4 0℃ .并且上述矿物组合可见于某些温泉的深部钻孔中 ,计算结果与实际地质情况相吻合 .结果表明固定铝log(Q/K)图解法可以恢复温泉系统的热平衡状态     

混合热源与热泵联动空调技术及其在天津"975"工程中的应用

混合热源与热泵联动空调技术以天然、廉价和低品位的资源为主,以高品位资源为尖峰负荷的系统能源配置设计新方法,实现以单投入多功能的新型能源利用方式替代多投入单功能传统的能源利用方式,使建筑物的空调系统具有经济、节能与环保等特点.该项技术能较好地应用于能源获取难度大、单一冷热源不能满足要求的工程.在天津"975"工程供暖及制冷系统中的应用结果表明:混合热源与热泵联动空调技术成功地解决了系统的冷热源、热(冷)负荷需求大等难题,具有明显的环境与经济效益.