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攀西裂谷带内超基性碱性岩和层状辉长岩^40Ar-^39Ar年龄——以鸡街、大向坪和太和岩体为例 总被引：5，自引：0，他引：5
对分布在攀西古裂谷带内的禄丰县鸡街和大向坪超基性碱性环状杂岩体中霞辉岩，以及西昌太和层状辉长岩等两类岩石进行全岩^40Ar-^39Ar坪年龄测定，结果表明鸡街岩体和大向坪岩体中霞辉岩年龄范围在214～193Ma，相当于晚三叠世，属于印支期。总体上，超基性碱性环状杂岩的侵位时间略晚于含矿辉长岩；太和层状辉长岩^40Ar-^39Ar坪年龄，由于过剩Ar等原因的扰动，使其年龄值远远高于成岩年龄。暗示全岩或辉石单矿物等不适合作为攀西地区层状辉长岩定年的对象。 相似文献
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大地热流是地球内热在地表最为直接的显示,并能给出发生于地球内部深处各种作用过程间能量平衡的信息,因而日益引起地球科学界的广泛兴趣和普遍关注。我国大地热流研究始于60年代,易善锋(1966)曾报道过东北中生代盆地的三个热流数据。1979年,中国科学院地质研究所地热组正式公布了我国第一批大地热流数据25个。近十年来,不同单位和作者在华北、东北、攀西、西藏等地区又先后获得了一批热流数据。最近,本文第一作者受国际热流委员会的委托,负责将我国大陆地区热流数据进行汇总并作统计分析,以便纳入“世界热流数据汇编”。 相似文献
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Successive temperature logs have been obtained over a period of two years in three closely-spaced boreholes in the Lac du Bonnet batholith of the Superior Province of the Canadian Shield. Two of the boreholes, of depth 450 m and 830 m, intersect a dipping fracture zone at 435–450 m. In both holes water is flowing from near the surface to the fracture zone at approximately 1.5–1.9·10−5 m3 s−1, the flow being inferred from analysis of the temperature logs. Below 25 m, temperatures in these two holes are 0.22–0.28 K lower than those in the third, 145 m, hole.The temperature data have been combined with over 200 thermal conductivity measurements on core samples to produce heat flow values. In the deepest hole heat flow above the fracture zone is 16% higher than that below the zone. This indicates that water is flowing up the fracture zone. The flow rate is approximately 0.3 g s−1 m−1, and the flow has existed for thousands of years.Observation of thermal effects of water flow in massive, relatively unfractured plutons in a region having little topographic relief causes one to be concerned about the reliability of heat flow values measured in similar environments.The regional heat flow is taken to be 50 mW m−2 after correction for glaciation effects. The average value of 24 determinations of radioactive heat generation in granitic core samples is 5.23 ± 1.11 μW m−3, which is more than three times higher than expected for such a heat flow in the Superior Province. This implies that the layer of high radioactive heat generation is thin, being not more than 4 km and probably about 1.3 km thick. 相似文献
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Analysis of factors affecting heat flow density determination in the Liaohe Basin,North China 总被引：1，自引：0，他引：1
Structural relief of the pre-Cenozoic basement and groundwater flow have been found to be the two most important factors affecting the heat flow density determinations in the Liaohe Basin. The reason for the significant effect of basement relief upon subsurface temperature and heat flow density patterns is the strong contrast of thermal conductivity between basement rock and the sedimentary cover. Simplified model computations indicate that the heat flow density in the region of basement uplift is 1.35 times greater than that in the region of depressions. Field observations indicate that the temperatures at shallow depths (less than 1200 m) are strongly perturbed by groundwater flow leading to reduced temperatures and geothermal gradients in the Neogene formation. Comparison of observed and calculated gradients reveals that reduced gradients and heat flow density occur in the groundwater recharge area whereas these parameters are enhanced in the discharge area. After taking the perturbing factors into account, a regional heat flow value of 65 ± 9 mW/m2 is obtained. 相似文献
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Complex geological and geophysical data obtained during recent research by the Marine Arctic Geological Survey Expedition
OJSC (MAGSE) indicate that the Riphean Chapoma graben located on the southeastern shore of the Kola Peninsula has its extension
under the Gorlo Strait of the White Sea water area and joins the Leshukonsk riftogenous graben as an extended narrow trench
in the crystal foundation of the platform. From this it follows that the Chapoma graben is the central segment of the White
Sea paleorift system. Only the northwestern edge and probably the upper part of the graben section outcrop on the Kola Peninsula,
which represents a highly elevated block of the platform foundation. To emphasize the unity of this paleorift zone, it makes
sense to call it the Chapomo-Leshukonsk Paleorift in contrast to the traditional name Kerets-Leshukonsk. The echelon position of the riftogenous troughs of the Chapomo-Leshukonsk paleorift, the form itself of the Leshukonsk and
Azopolsk troughs being close to pull-apart assumes their occurrence and development under transtension conditions with elements
of the right-side shear along the steep northeastern edges of the grabens. 相似文献
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四川攀西地区地处我国东部地台区和西部地槽区的接合部位,是著名的攀西裂谷所在地;地处金沙江、雅砻江、大渡河小三江流域区,拥有丰富的水力资源和矿产资源;该区也是我国少数民族相对聚集的地区。调查显示,该区拥有丰富的地质遗迹景观资源,但至今尚未建立一个地质公园,旅游资源开发也相对滞后。本文以近期调研资料为依据,根据地质遗迹景观资源的发育分布特征,提出了该地区建立地质公园的思路和设想,即根据各个景观地在地质成因上的相互联系,按景观地的组合形式,建立地质公园;以重要的地质遗迹景观地为中心,与相邻近的大型水电工程组合,建立地质公园;以著名的大型矿山为中心,联合邻近的地质遗迹景观,建立矿山公园。并通过典型实例作了简要阐述。 相似文献
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裂隙岩体流-热耦合传热的三维数值模拟分析 总被引：1，自引：0，他引：1
通过对潘西煤矿水文地质条件的分析,基于裂隙岩体的流-热耦合数学模型,描述了裂隙岩体渗流场分布和水流及岩体的温度场分布,并结合边界条件及计算参数对裂隙岩体的流-热耦合传热进行了数值模拟和分析。数值模拟结果表明,岩体内裂隙水流所引发的热量迁移,对裂隙岩体的温度场分布有重要影响。断裂带及地下水流的存在改变了岩体的原有温度场分布。在渗流初期,温度梯度矢量沿渗流方向向两侧岩体方向流动,由于两侧岩体的渗透性系数低于断裂带处的渗透性系数,右侧等温线及温度梯度矢量方向逐渐向渗流方向移动,改变了两侧岩体的温度场分布。通过对断裂带内裂隙水流渗透性系数的折减,分析渗透性系数发生变化时对岩体温度场分布的影响,渗透性系数越大,伴随的热量迁移增大,对岩体的温度场分布的影响也越大。 相似文献
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选取云南高原向贵州高原过渡地带上的乌江南源——贵州省三岔河上游流域作为研究对象，分别提取其流域内的花渔洞地下河流域与三塘地下河流域的地形指标，分析两者的流量衰减现状，并探讨了岩溶地表形态和岩溶含水介质结构之间的关系。结果显示:（1）花渔洞地下河流域的平均起伏度为73.2 m，可分为高起伏度的Ⅰ区（均值122 m）和低起伏度的Ⅱ区（均值64 m）两个区，其分别占整个流域面积的14.9%和85.1%；三塘地下河流域的平均起伏度为87.6 m，可分为高起伏度的Ⅰ区（均值106 m）、中起伏度的Ⅱ区（均值81 m）和低起伏度的Ⅲ区（均值48 m）三个区，其分别占流域面积的40.2%，49.7%和10.1%；（2）花渔洞地下河流域各阶段的衰减系数为0.000 3，0.000 1，0.000 06（0.5 h）-1，总蓄水量达2 199.356×104 m3，各亚动态蓄水量分别占总蓄水量的0.1%，9.9%、90.0%；三塘地下河流域各阶段的衰减系数为0.001、0.000 3、0.000 1（0.5 h）-1，总蓄水量为2 310.902×104 m3，各亚动态蓄水量分别占总蓄水量的9.4%、30.8%、59.8%。这表明地面起伏度和衰减动态之间可能存在着关联性，即高起伏度对应岩溶发育强烈的管道流，低起伏度对应导水通道较小的裂隙、溶隙等含水层。 相似文献