共查询到20条相似文献，搜索用时 218 毫秒
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海底热流测量对于海洋地热学基础研究与天然气水合物等新兴海洋矿产资源勘测具有重要意义。海底热流原位测量是现代海底热流探测技术的发展方向。针对我国目前在该项技术的落后局面,通过对现存几种热流原位测量技术的原理与技术特点的对比与分析,指出了我国未来发展海底热流测量技术的方向与重点。 相似文献
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钱翼鹏 《海洋地质与第四纪地质》1982,(4)
地热流是地球物理学的一个重要分支.自五十年代开始,特别是在深海大洋探测地热流技术成功以后,它的研究成果已运用到地热学、地质基础理论、地球形成理论及能源科学等方面.因此,当前地热流研究已受到地学界的普遍重视.1979年底至1980年初,中美联合调查南海地质,在深海底测定了地热流.本文将简要地介绍这次调查采用的热流测定技术及其工作成果. 相似文献
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海底光缆工程发展20年 总被引：4，自引：0，他引：4
对全球第一条海底光缆问世后20年来海底光缆工程发展的历程作了简要回顾。随着光纤传输技术的不断进步,海底光缆的通信技术得到了飞速发展,近20年来,其商用系统已经历了四代。海底光缆工程发展的重要标志,还体现在海底光缆施工技术的日趋完善,水下定位、海底数字式高分辨率的地球物理探测、海底原位测试等高新技术在海缆路由调查与埋设评价调查中的广泛应用。此外,对海底光缆市场与行业结构所经历的深刻变化作了分析,并预测了国际海底光缆网络的发展和市场前景。 相似文献
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海底表层沉积物具有多相、多颗粒、多形态的组成结构，导致其声学特性复杂多样。通过分析压缩波速度和切变波速度特性的研究现状，指出有待于解决的科学问题和关键技术问题。在分析国内外有关海底沉积层声速特性研究基础上，提出采取系统、可控的实验测量手段解决当前测量存在的4点问题。综合分析了压缩波速度和切变波速度存在的统计回归关系和理论分析关系，探讨了当前地声反演、采样样品声学测量、原位声学测量3种方法存在的测量尺度、测量频率、测量状态等的差异，探讨建立不同测量方法和测量技术对测量结果进行统一性解释的方法，从而获得不同类型、不同区域的海底表层沉积物真实的声速特性。最后，从实验室声学测量、物理力学参数测量、流固耦合特性分析、原位测量及海底监测、采样测量与原位测量的误差分析及校正、海底大纵深声学测量6个方面提出技术需求，为提高声学探测海洋和海底的精度服务，推动海洋声学探测和海洋工程发展。 相似文献
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山东半岛硅热流值与区域地质条件的关系 总被引：3，自引：1，他引：3
据地下水中ＳｉＯ２含量计算山东半岛硅热流值。以此为基础初步探讨本区的地热场特征及其与区域地质条件的关系。指出：１．山东半岛平均热流值与全球平均热流值接近，但比一般古老地块略高。２．划分出三个地热异常区，在大地构造上，两较高热异常区分别对应于胶北和文登隆起；较低热异常区与胶莱盆地相应。３．地热场总特征及其区域热异常的形态主要与近地表的地层岩性、构造形态和断裂发育程度等地质条件有关，而与中生代的岩浆活动无关，但第四纪岩浆活动对胶北隆起局部（蓬莱一带）热异常有重要作用 相似文献
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对收集、整理的462组大地热流和地温梯度数据进行统计分析,结果表明南海北部陆缘具有普遍偏高的大地热流和地温梯度,大地热流总体表现为由陆架向洋盆方向递增的趋势。海底热流资料经稳态温度场计算南海北部随深度变化的热流和温度分布,获取热居里面深度,与地磁资料反演的居里面深度进行对比,发现南海北部中、下陆坡磁居里面深度浅于热居里面深度,处于地热不平衡状态。通过对地壳结构、拉张因子、莫霍面埋深、断裂带及火山活动的综合分析,表明南海北部陆缘地热状态受控于地壳拉张减薄和莫霍面抬升的构造格局,裂后晚期局部岩浆活动对地热状态亦有影响。 相似文献
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对冲绳海槽１９８４－１９９０年的实测热流值，利用数字滤波方法计算，得到反映该区深部地壳热状态的区域热流值为８０－１６０ｍＷ／ｍ＾２，用Ｂ样条函数法对其作数值模拟，计算出海槽地温场模式，并以此研究冲绳海槽海底高热流的形成机制，得出冲绳海槽热流值的区域性变化与綦中地质构造格局呈正相关，高热流是该区现代构造活动所致，其明显特征是地壳减薄，地幔上拱等结论。 相似文献
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Geothermal modeling of the gas hydrate stability zone along the Krishna Godavari Basin 总被引：1，自引：1，他引：0
A wide-spread bottom simulating reflector (BSR), interpreted to mark the thermally controlled base of the gas hydrate stability zone, is observed over a close grid of multichannel seismic profiles in the Krishna Godavari Basin of the eastern continental margin of India. The seismic data reveal that gas hydrate occurs in the Krishna Godavari Basin at places where water depths exceed 850 m. The thickness of the gas hydrate stability zone inferred from the BSR ranges up to 250 m. A conductive model was used to determine geothermal gradients and heat flow. Ground truth for the assessment and constraints on the model were provided by downhole measurements obtained during the National Gas Hydrate Program Expedition 01 of India at various sites in the Krishna Godavari Basin. Measured downhole temperature gradients and seafloor-temperatures, sediment thermal conductivities, and seismic velocity are utilized to generate regression functions for these parameters as function of overall water depth. In the first approach the base of gas hydrate stability is predicted from seafloor bathymetry using these regression functions and heat flow and geothermal gradient are calculated. In a second approach the observed BSR depth from the seismic profiles (measured in two-way travel time) is converted into heat flow and geothermal gradient using the same ground-truth data. The geothermal gradient estimated from the BSR varies from 27 to 67°C/km. Corresponding heat flow values range from 24 to 60 mW/m2. The geothermal modeling shows a close match of the predicted base of the gas hydrate stability zone with the observed BSR depths. 相似文献
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The Dongpu depression is located in the southern Bohai Bay Basin, North China, and it has abundant oil and gas reserves. There has been no systematic documentation of this depression's temperature field and thermal history. In this article, the present geothermal gradient and heat flow were calculated for 68 wells on the basis of 892 formation-testing data from 523 wells. Moreover, the Cenozoic thermal history was reconstructed using 466 vitrinite reflectance data from 105 wells. The results show that the Dongpu depression is characterized by a medium-temperature field between stable and active tectonic areas, with an average geothermal gradient of 34.8 °C/km and an average heat flow of 66.8 mW/m2. The temperature field in the Dongpu depression is significantly controlled by the Changyuan, Huanghe, and Lanliao basement faults and thin lithosphere thickness. The geothermal gradient twice experienced high peaks. One peak was during the Shahejie 3 Formation depositional period, ranging from 45 °C/km to 48 °C/km, and the second peak was in the middle and late of the Dongying Formation depositional period, ranging from 39 °C/km to 40 °C/km, revealing that the Dongpu depression experienced two strong tectonic rifts during the geothermal gradient high peak periods. The geothermal gradient began to decrease from the Neogene, and the geothermal gradient is 31–34 °C/km at the present day. In addition, these results reveal that source rock thermal evolution is controlled by the paleo temperature field of the Dongying Formation depositional period in the Dongpu depression. This study may provide a geothermal basis for deep oil and gas resource evaluation in the Dongpu depression. 相似文献
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This study, using laboratory experiments and scaling analysis, evaluates the influence of geothermal heating on global oceanic circulation. Upon a well-developed large-scale convective flow, an additional heat flux perturbation δF/F is employed. The increments of flow and thermal properties, including eddy diffusivity KT, flow velocity V and bottom temperature Tb, are found to be independent of the applied heat flux F. Together with the scaling analysis of convective flow at different configurations, where the flow is thermally driven in the relatively low or extremely high turbulent thermal convections or the horizontal convection, the variances of flow properties, δKT/KT and δV/V, are found to be close to 0.5% and 0.75% at δF/F=2%. This means that the small heat flux perturbation plays a negligible role in the global convective flow. However, δTb/ΔT is found to be 1.5% at δF/F=2%, which would have a significant effect in the local region. The results might provide a clue to understanding the influence of geothermal heating on global oceanic circulation. It is expected that geothermal heating will contribute less than 1% in turbulent mixing and volume flux to global oceanic circulation, so its influence can be negligible in this situation. However, when it comes to the local environment, the influence of geothermal heating cannot be ignored. For example, temperature increases of about 0.5°C with geothermal heating would have a significant effect on the physical environments within the benthic boundary layer. 相似文献
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Particular features of the tectonic structure and anomalous distribution of the geothermal, geomagnetic, and gravity fields in the region of the Sea of Okhotsk are considered. On the basis of heat flow data, the ages of large-scale structures in the Sea of Okhotsk are estimated at 65 Ma for the Central Okhotsk Rise and 36 Ma for the South Okhotsk Basin. The age of the South Okhotsk Basin is confirmed by the data on the kinematics and corresponds to a 50-km thickness of the lithosphere. This is in accordance with the thickness value obtained by magnetotelluric soundings. A comparative analysis of the model geothermal background and the measured heat flow values on the Akademii Nauk Rise is performed. The analysis points to an abnormally high (by approximately 20%) measured heat flow, which agrees with the high negative gradient of gravity anomalies. The estimates of the deep heat flow and the basement age of the riftogenic basins in the Sea of Okhotsk were carried out in the following areas: the Deryugin Basin (18 Ma, Early Miocene), the TINRO Basin (12 Ma, Middle Miocene), and the West Kamchatka Basin (23 Ma, Late Oligocene). The temperatures at the boundaries of the main lithological complexes of the sedimentary cover are calculated and the zones of oil and gas generation are defined. On the basis of geothermal, magnetic, structural, and other geological-geophysical data, a kinematic model of the region of the Sea of Okhotsk for a period of 36 Ma was calculated and constructed. 相似文献