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41.
三维相干切片断层多边形检测 总被引:7,自引:2,他引:7
作者在本文中将三维切片视为二维图像,利用图像边缘检测技术,检测出相干切片上断层多边形,并将其直接投影到测网底图上,用于构造成图。该项技术不仅提高了用相干切片解释断层的精度,而且提高了断层解释效率,使相干数据体技术在三维解释中的作用得到更大的发挥。实际应用表明,三维相干切片断层多边形检测技术,是全三维高精度解释的有力工具,提高了解释效率,缩短了解释周期。 相似文献
42.
应用改进的相干算法提高三维地震资料解释精度 总被引:2,自引:0,他引:2
作者在文中详细探讨了C1、C2和C3三种相干算法及其。根据三维地震数据体的特点提出了实用的相干算法,并编制了相应的软件。我们对三种相干算法对应相干数据体的解释结果进行了细致的分析,C2相干算法基本能够平衡提高横向分辨率和信噪比之间的矛盾,而C3相干算法则取得了更精确的效果。 相似文献
43.
44.
The time series BT profiles and surface winds and atmospheric pressure, collected in the deep waters off Ratnagiri and Karwar
during summer monsoon were utilized to document the characteristics of internal waves (IW). Low-frequency (≤2, cycle per day
(cpd)) IW off Ratnagiri are found to propagate at 83 cm/s with wavelengths of 45 km and wave heights upto 40 m. These parameters
for high-frequency (>2 cpd) IW off Karwar correspond to 99 cm/s, 3 km and 23 m. The IW off Karwar appear to leave the station
at 70° (±10°) (measured from the horizontal). The data sets were further analysed to address the harmonic composition of the
IW and identify the possible sources for the observed IW fields. Power spectra of the IW indicated energy peaks at inertial
(0·6 cpd) and tidal (1 and 2 cpd) frequencies off Ratnagiri and in the high-frequency band of 0·5–2·0 cycles per hour off
Karwar. The coherence between the IW and wind/tide is found to be good at several frequencies within the IW spectrum. This
feature probably suggests tides as a source for the IW of tidal frequencies and winds and tides as a joint source for the
IW at the remaining frequencies. 相似文献
45.
清水塘多因复成铅锌矿床地质特征及深边部盲矿体立体定量预测 总被引:1,自引:0,他引:1
在综合分析了清水塘矿床地质特征基础上,运用成矿系统功能模拟原理,在矿区内建立了主要矿脉的立体定量预测模型,并在主矿脉的深边部有效地预测了盲矿体,求出了一定的金属矿量. 相似文献
46.
The deep seismic reflection method has been play-ing an important role in revealing lithospheric struc-tures as well as geodynamic processes within the crustand uppermost mantle[1-3]. After careful analyzing the deep seismic reflection profiles along some of the Mesozoic plutons, the author found that the crustalstructures around these intrusions usually correlate with a special seismic fabric called the seismic multi-arch structure[1]. A seismic multi-arch structure consists of some arch refl… 相似文献
47.
48.
牛庄洼陷烃源岩体的几何学描述 总被引:1,自引:0,他引:1
油气资源评价,应该从以构造单元为评价单元,走向以蕴含于构造单元内的生成油气的地质体为单元。界定生成油气的烃源岩体,要综合应用地质、有机地球化学、地球物理等学科从三维空间上来进行。本文以牛庄洼陷为例,具体地使用岩心、测井曲线、古生物化石、有机地球化学指标、地震剖面等资料,描述了沙四上亚段的低熟及成熟烃源岩的几何形态,以及它们在生成演化上的相互联接。 相似文献
49.
The Canary Archipelago is an intraplate volcanic chain, located near the West African continental margin, emplaced on old oceanic lithosphere of Jurassic age, with an extended volcanic activity since Middle Miocene. The adjacent seafloor does not show the broad oceanic swell usually observed in hotspot-generated oceanic islands. However, the observation of a noticeable depth anomaly in the basement west of the Canaries might indicate that the swell is masked by a thick sedimentary cover and the influence of the Canarian volcanism. We use a spectral approach, based on coherence analysis, to determine the swell and its compensation mechanism. The coherence between gravity and topography indicates that the swell is caused by a subsurface load correlated with the surface volcanic load. The residual gravity/geoid anomaly indicates that the subsurface load extends 600 km SSW and 800 km N and NNE of the islands. We used computed depth anomalies from available deep seismic profiles to constrain the extent and amplitude of the basement uplift caused by a relatively low-density anomaly within the lithospheric mantle, and coherence analysis to constrain the elastic thickness of the lithosphere ( Te ) and the compensation depth of the swell. Depth anomalies and coherence are well simulated with Te =28–36 km, compensation depth of 40–65 km, and a negative density contrast within the lithosphere of ∼33 kg m−3 . The density contrast corresponds to a temperature increment of ∼325°C, which we interpret to be partially maintained by a low-viscosity convective layer in the lowermost lithosphere, and which probably involves the shallower parts of the asthenosphere. This interpretation does not require a significant rejuvenation of the mechanical properties of the lithosphere. 相似文献
50.