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1.
开展关中盆地腹部深层地下热水起源成因的研究,对推动研究区地下热水的可持续开发利用意义重大。中国大多数地下热水赋存地区的热水样点与现代循环水的关系密切,多属循环型热水,而关中盆地深层地下热水却远离大气降水线,δ~(18)O漂移显著,对此,国内外学者专家对引起关中盆地地下热水δ~(18)O富集的主要因素有不同的认识。应用同位素水文地球化学方法结合关中盆地地质构造演化,对关中盆地不同构造单元深层地下热水δ~(18)O富集的主控因素进行探索性研究。研究结果表明,影响关中盆地深层地热水δ~(18)O富集的因素是多元的,因热储环境开发度而异,在较封闭的热储条件下,其主控因素是水岩反应。热储蒸发实验的结果表明,深层地热水在进入地层前作为补给水源时,存在一定程度的蒸发作用,入渗后进入较封闭热储环境时则主要受控于水岩作用的影响,且受水岩反应的影响程度为固市凹陷咸礼断阶东咸礼断阶西及西安凹陷。 相似文献
2.
西安地区地热水和渭北岩溶水同位素特征及相互关系 总被引：7，自引：0，他引：7
依据采自西安地区300到3000米深地热井中地热水的水化学成分和同位素成分,确定出地热水的主要补给源和循环路径。地热水δ~(18)O 值变化于-11.8‰～-3.1‰VSMOW 之间,而δD 值变化幅度很小,在-87～-80‰VSMOW 之间,与西安市区现代大气降水的δD 值(～-60‰VSMOW)明显不同。在δ~(18)O～δD 关系图上,浅层地热水(〈1500米〉落在大气降水线上,而深层地热水(>1500米)向右侧偏离了大气降水线,呈现显著的氧同位素正向漂移现象。氧同位素由秦岭山前向盆地内部逐渐富集,在盆地内部随井深成正相关。据此判断,西安地热水的补给区位于秦岭山区。~(14)C 值表现为与氧同位素相反的变化趋势,~(14)C 年龄值在6,000～30,000年之间,表明地热水的地下循环时间很长。由井间~(14)C 年龄差异估算出从南到北地热水平均流速为1.7米/年,从西到东为2.5米/年。这些特征与渭北岩溶水截然不同,表明西安地区地热水与渭北岩溶水之间,虽然在空间上有密切联系,但分属于不同的水文地质单元,有各自独立的补径排系统。 相似文献
3.
对屏山灯盏窝地热水和地下水的化学和同位素分析表明:灯盏窝地热井揭露的两个热储层,三叠系雷口坡组热储埋深623~1 111m,水温39.4℃,TDS含量为15 800mg/l,水化学类型为Cl·SO4-Na型;二叠系栖霞茅口组热储埋深2 040~2 618m,水温78.3℃,TDS含量为450mg/l,水化学类型HCO_3~--Cl·Ca-Na型。雷口坡地热水的δD为-47.5‰,δ~(18)O为-7.7‰,是大气降水与沉积水混合形成;栖霞茅口组热水δD为-64.8‰,δ~(18)O为-10.9‰,来源于大气降水。热水与地下冷水水化学、同位素组成有较大差异,说明经历了比冷水更长的循环深度和不同的成因,深部热水的补给与附近泉水、地表水和金沙江水关系不大,灯盏窝热水发育受五角堡-楼东背斜核、糖房湾穹隆构造控制,该区地热水具有较高的开采利用潜力。 相似文献
4.
粤港澳大湾区地热资源丰富, 但人们对区内地下热水地球化学特征的认识还存在一定争议。本文对27组地下热样品的水化学分析表明, 研究区内陆地热水的水化学相主要为重碳酸盐型, 沿海地热水则主要呈氯离子型。地热水的δ2H和δ18O值分别为–30‰ ~ –48‰和–5.2‰ ~ –7.5‰。内陆地热水的δ2H和δ18O值沿当地大气降水线(LMWL)分布, 表明内陆地热水来源于当地大气降水补给。沿海地热水的δ18O值偏离当地大气降水线并向海水数据点靠拢, 沿海地热水的δ18O值与Cl–含量呈强正相关, 表明沿海地热流体源于当地大气降水和海水混合补给。经典地球化学温标、多矿物平衡状态模拟、硬石膏-玉髓矿物对饱和指数模拟以及硅-焓混合模型揭示的粤港澳大湾区地热系统热储温度为104~156 ℃。内陆地热水中的地下冷水的混入比例为52%~84%, 沿海地热水中海水的混入比例高达37%。内陆和沿海地热水的最大循环深度分别为3300~4800 m和3200~4200 m, 没有显著差别。水化学组成与氢氧同位素研究均表明, 水岩反应和混合作用共同控制着研究区地下热水的地球化学特征。 相似文献
5.
地热资源作为清洁能源在经济建设和环境保护中倍受青睐,而地下热水循环机理的研究是合理开发地热资源的前提。以关中盆地横跨山前冲积扇-黄土台塬-冲积平原三类地貌单元的典型剖面为研究对象,在地下热水野外调查的基础上通过地下热水动力场、化学场和同位素场的研究构建了关中盆地秦岭山前地下热水的循环模式:地下热水主要来自第四纪末次冰期海拔2 006~2 032 m大气降水的补给,大气降水经秦岭山前断层破碎带向下渗透进入盆地深部,在异常高的地热梯度下受热后沿着渭河北侧导水断裂带上升。从补给径流区至排泄区,地下热水径流速度由快变缓,年龄逐渐变老(从21 097 a到31 809 a),水化学类型由HCO3—Na型向Cl—Na型过渡,水岩作用从弱到强,依次发生了溶滤作用、脱硫酸作用和去白云岩化作用,可交换岩石对地下热水18O的贡献比例依次为0%、10%、10%~25%。 相似文献
6.
陕西咸阳地热田地热流体成因研究 总被引：1，自引：0，他引：1
陕西咸阳地热田位于关中盆地腹地,横跨两个不同的基底构造和岩性单元,南北分界线为渭北断裂。研究区地热水的水化学类型主要是Cl—Na型,渭北断裂北侧的水比南侧的水相对更成熟。氢氧同位素证据表明咸阳市区和武功县城的地热水来自于秦岭山区大气降水的补给;地热水γ(Na~+)/γ(Cl~-)均大于0.85,阳离子交换指数位于-0.42～5.93之间,脱硫酸系数均大于1,推断研究区的地热水主要形成于溶滤作用,其中武功地区的热储层较封闭,可能存在沉积水;惰性气体同位素n(~3He)/n(~4He)—n(~4He)/n(~(20)Ne)表明流体循环仅发生在地壳深度内,没有幔源物质的补给。 相似文献
7.
陕西关中盆地中部地下热水H、O同位素交换
及其影响因素 总被引：4，自引：1，他引：3
对关中盆地地下热水δ＆18O和8D数据的研究表明：盆地中部西安、咸阳深部的地压地热流体发生明显的δ^18O同位素交换,并出现^2H同位素交换,表明热储流体发生了强烈的水岩反应,盆地周边及中部的非地压地热流体^18O交换则不明显。根据研究区^18O同位素的交换程度（用^2H过量参数d表征）和水化学资料,可将关中盆地热储流体分为循环型和封闭型热储流体2类。地热水埋深越大、滞留时间越长、TDS和温度越高、地质环境越封闭,18^O交换程度就越大。西安和咸阳地下热水分属于不同的地热系统,具有不同的补给来源。 相似文献
8.
应用Sr含量、87Sr/86Sr比值及热水水化学资料,结合关中盆地地质构造演化对关中盆地腹部深部热储流体的补给起源、路径、成因及混合作用进行研究。结果表明:西北方向为咸礼断阶东南热储流体接受补给的来水方向;咸礼断阶西北水源来水方向为西北部;西安城区补给源有少量来自秦岭北麓,其主要水源来水方向为西部及北部,而长安区热储流体接受来自秦岭北麓正南方向的补给。固市凹陷深层热水封闭性好、水岩反应显著,属残存沉积水;咸礼断阶东南咸阳城区深层热水封闭性较好、水岩反应较为显著,是含残存沉积水的古溶滤水;西安凹陷西安城区热水半封闭,存在一定水岩作用的古溶滤水;长安东大中层-浅层热水开放性好,属混入现代降水的古溶滤水。 相似文献
9.
结合石林盆地地热异常及地热钻孔资料,对石林盆地地热田的热储构造条件、地热地质特征及地下水化学特征进行研究,该地热田热储层为元古界震旦系白云岩、白云质灰岩,热水径流特征和地温场特征受九乡石垭口断裂、牛头山古陆控制。钻孔资料显示,地温梯度为(1.5~4.8)℃/100 m,地热类型为深循环层状地热田,地下热水水化学类型为HCO3-Ca。从水文地质条件看,地下热水补给有限,应控制地热水的开发利用。 相似文献
10.
通过对关中盆地地热井中地下热水的同位素和水化学成分分析,结合研究区的地热地质和水文地质条件,进行了地下热水补给时的温度研究,结果表明,关中盆地地下热水接受补给时的温度以西安地区最低,咸阳次之。同时应用Na-K-Mg三角图和水化学平衡温度理论的方法,估算在平衡条件下关中盆地最大热储温度为118℃。热储温度计算结果表明,关中盆地腹部应为中低温热储层。 相似文献
11.
Guboglo M. N. 《GeoJournal》1980,4(1):53-58
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen. 相似文献
12.
Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth
B. P. Kondratyev 《Astronomy Reports》2017,61(8):709-714
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″. 相似文献
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14.
Chronological analyses of correlations between certain global repeating events (mass extinctions of marine organisms, meteorite impacts, and flashes in the frequency of geomagnetic reversals) during the Phanerozoic Eon and the motion of the solar system in the Galaxy are presented for five rotationally symmetrical models for the regular Galactic gravitational field. Thirteen of sixteen mass-extinction events can be described by a repetition interval of 183±3 million years. This is in agreement with the anomalistic period (interval between two subsequent passages of the Sun through the apocenter of its Galactic orbit) in the model of Allen and Martos. The positions of the minima and maxima in Gaussian functions approximating the frequency distribution for geomagnetic reversals also agree with the times of passage of the Sun through the apocenter and pericenter, respectively, of its Galactic orbit in this model. The maximum in the distribution of the deviations of the dates of mass extinctions from the nearest dates of impacts of large, crater-forming bodies is close to zero, providing evidence that many such events are correlated. As a rule, extinctions follow impact events. The impacts of large bodies have occurred most often when the solar system passes through the Galactic plane, while mass extinctions occur more often at some distance from the Galactic plane (about 40 pc). As a rule, intervals of increases in the frequency of geomagnetic reversals coincide with dates of impacts of large bodies. At the same time, these intervals do not show a clear correlation with the dates of mass extinctions. The intensity of mass extinctions, like the energy released by impacts, is consistently higher in periods when the Sun is moving from the apocenter toward the pericenter of its orbit, than when it is moving from the pericenter toward the apocenter. Thus, there is evidence for a variety of relationships between repeating global events in the Phanerozoic and the motion of the Sun in the Galaxy. Long-period variations in the frequency of geomagnetic reversals are correlated with the orbital motion of the Sun, and increases in the frequency of geomagnetic reversals are correlated with impacts. Mass extinctions are correlated with the impacts of large bodies, whose motions may have been perturbed by clouds of interstellar material concentrated toward the Galactic plane and by the shock front associated with the Perseus spiral arm, through which the solar system passes. The velocity of the Sun relative to the spiral pattern is estimated. 相似文献
15.
位于华北和扬子两板块碰撞带中的苏鲁榴辉岩形成的温压条件不但是超高压，而且是高温。榴辉岩的PTt轨迹表明其为陆-陆磁撞俯冲带的产物。榴辉岩的区域性围岩花岗质片麻岩为新元古代同碰撞期花岗岩，榴辉岩及其他直接围岩皆呈包体存在于其中，并见新元古代花岗岩呈脉状侵入榴辉岩包体中。区域性围岩新元古代花岗岩的锆石中发现有柯石英、绿辉石等包裹体，表明新元古代花岗岩的组成物质也经受过超高压变质作用，且榴辉岩与围岩新元古代花岗岩的锆石U-Pb体系同位素年龄基本相同。但新元古代花岗岩所记录的变质作用和变形作用期次（或阶段）却少于榴辉岩。椐上述可得如下推断：超高压榴辉岩与新元古代花岗岩岩浆是同时在碰撞带底部（俯冲板块前部）形成的；榴辉岩的第一折返阶段是由新元古代花岗岩岩浆携带上升的，其第二折返阶段是和新元古代花岗岩一起由逆冲及区域性隆起而上升，遭受剥蚀。 相似文献
16.
某高速公路下伏煤矿采空区稳定性分析 总被引：10，自引：0，他引：10
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。 相似文献
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18.
摩擦桩基桩土间极限摩阻力取值问题探讨 总被引：1，自引：0，他引：1
通过对广珠东线高速公路横沥大桥的试桩及土体的工程地质条件分析,总结出影响摩擦桩基桩土间极限摩阻力取值的一般问题以及解决问题的方法和措施。 相似文献
19.
The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads 总被引：3，自引：1，他引：2
Clemente Irigaray Francisco Lamas Rachid El Hamdouni Tomás Fernández José Chacón 《Natural Hazards》2000,21(1):65-81
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning. 相似文献
20.
The structure of the eastern Pyrenees consists mainly of south-directed thrusts involving basement and cover rocks. An antiformal stack developed by the piling up of basement thrust sheets which outcrop in the Axial zone. These structures account for a thin-skinned thrust model rather than a vertical fault model in which the Axial zone would be essentially autochthonous, and the North-Pyrenean fault the axial plane of a fan thrust system. New data from the Eastern Pyrenees and the thin-skinned model suggest that(1) the structure east of the Pedraforca nappe is similar to that of the Central Pyrenees; (2) the cover rocks of the South-Pyrenean units and of the Axial zone-after restoration—built up a northwards-thickening prism consistent with the existence of a unique Pyrenean sedimentary basin during Mesozoic time; (3) the Axial zone is only a complex antiformal stack developed as a part of South-Pyrenean system related to the Paleogene thrusting-tectonics. The Axial zone palaeogeographic area had no special meaning during Mesozoic time. 相似文献