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541.
珠江口盆地惠州凹陷HZ25-7构造是近年来发现的一个重要的深层古近系含油岩系,因岩性复杂,致使物源、沉积环境及有利储层分布等认识不清,给进一步勘探开发带来很大难度。以古近系文昌组和恩平组为研究对象,利用高分辨率成像测井资料,结合岩心分析资料和常规测井资料,精细分析了该区地层的岩性特征和沉积构造特征,认为目的层段为辫状河三角洲沉积,并建立了陆上辫状河道、水下分流河道及河口坝3类关键微相砂体的测井响应特征;通过对井点处古水流方向及物源方向分析,认为物源主要来自南部,并长期持续存在。最后,结合区域地质背景及综合研究,建立了文昌组关键砂体的沉积微相平面展布,指出了研究区有利储层的分布方向。 相似文献
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543.
B.?Zogala R.?DubielEmail author W.?M.?Zuberek M.?Rusin-Zogala M.?Steininger 《Environmental Geology》2009,58(1):1-9
The survey has been carried out in the area of 0.23 km2 of the former military underground fuel base. The oil derivative products were observed in excavations and the laboratory
tests confirmed the occurrence of hydrocarbons (>C12) in soils. The purpose of the survey was to determine the spatial extent
of the contamination. The studied area is covered by postglacial sediments: sands, gravels and till. The first water table
was observed at a depth of 10–12 m. The detailed electromagnetic measurements with Geonics EM31-MK2 conductivity meter were
performed in the whole area of the former fuel base. Obtained results were elaborated statistically and the map of apparent
electrical conductivity to a depth of 6 m was created. Many local low conductivity anomalies were observed. The measurements
with Geonics EM34-3XL were performed along one A–A′ profile and 1D electromagnetic modelling along with this profile was calculated
to obtain the electrical conductivity cross-section to a depth of 30 m. Two-dimensional electrical resistivity imaging measurements
were carried out along the same profile and the resistivity cross-section to a depth of 20 m was performed. Both conducivity
and resistivity cross-sections show anomalous zones. The zones correlate with oil contaminated zones very well. 相似文献
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545.
After a CCD image of the four Galilean satellites of Jupiter is obtained by a long focal length telescope, we can compare the theoretical positions of these satellites with their pixel positions so as to obtain the calibration parameters of the CCD field of view. In theory, when two of the four satellites have small enough separation, their relative positional measurement will have a good accuracy since the error existing in the solved calibration parameters has a direct proportional effect on the separation of the two satellites. The 347 CCD images taken by 1-m long focal length telescope at Yunnan Observatory in 2002-2005 are used to perform the experimental test. After we improve the centroid algorithm for the satellites and our former halo-removal technique, the results show that the positional measurement of two small-separation satellites has an external precision as good as 0.01-0.03 arcsec. This precision has comparability as that from rarely occurring mutual events of the Galilean satellites. This experiment confirms the finding of the “precision premium” firstly presented by Pascu [1994. An appraisal of the USNO program of photographic astrometry of bright planetary satellites. In: Morrison, L.V., Gilmore, G.F., (Eds.), Galatic and Solar System Optical Astrometry, pp. 304-311] using photographic observations. We believe that this type of observations, besides mutual event observations, might also be used to improve our knowledge of the orbital motions of the Galilean satellites because of its much more opportunities. 相似文献
546.
河道砂体宽/窄方位三维观测系统地震物理模型分析 总被引:1,自引:0,他引:1
The effect of the wide and narrow azimuth 3D observation systems on seismic imaging precision is becoming a hot area for studies of high precision 3D seismic acquisition methods in recent years. In this paper we utilize 3D physical seismic modeling experiments. A 3D channel sand body physical seismic model is constructed and two acquisition systems are designed with wide azimuth (16 lines) and narrow azimuth (8 lines) to model 3D seismic data acquisition and processing seismic work flows. From analysis of migrated time slice data with high quality and small size, we conclude that when the overlying layers are smooth and lateral velocities have little change, both wide and narrow azimuth observation systems in 3D acquisition can be used for obtaining high precision imaging and equivalent resolution of the channel sand body. 相似文献
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548.
本文简要地解释了衍射增强成像方法和光栅相衬成像方法的物理原理,详细地介绍了以这两种成像方法为基础的一阶相衬CT的物理模型及其重建算法的最新进展,着重分析这些重建算法的思路、特点和性能。这些重建算法基于相衬成像的物理原理,能够从一阶投影数据出发,直接重建样品内部的折射率分布,从而得到了弱吸收物质的高衬度CT图像。 相似文献
549.
分析了目前我国生产水准尺的工艺现状, 指出了造成水准尺精度长期得不到提高的原因。提出了一种使用感光成像法制造高精度水准尺的制造工艺。 相似文献
550.