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41.
多宝山超大型铜矿床的成矿构造环境 总被引:9,自引:0,他引:9
多宝山超大型铜矿床是我国典型的斑岩型矿床,主要产出于多宝山组岛弧建造和花岗闪长岩、花岗闪长斑岩中,成矿年龄为292~283Ma。根据地球物理异常及大量的基性和超基性岩体,以及通过对比两侧的岩石圈结构、古生物、结晶基底、成矿特征和地球化学特征,认为黑河一嫩江是一条重要的构造边界带,它是兴安和松嫩地块在早石炭世拼合、碰撞、造山隆起形成的。多宝山超大型铜矿床就是形成于两板块碰撞后隆起抬升构造环境的斑岩型铜矿床。 相似文献
42.
煤田地震勘探一直探寻着对小断层的自动检测方法,因受各种因素的影响,至今尚无良策。本文介绍了多元地震参数的模式识别方法,并通过模型及实测资料成功地检测到10m以下小断层。 相似文献
43.
Zhou Cuiying Wang Hongwei Wang Mei and Zhang YuxiaSeismological Bureau of Shandong Province Jinan China Center for Analysis Prediction SSB Beijing China 《中国地震研究》1997,(4)
In order to solve the problem of early estimation of moderately strong aftershock duration time in an earthquake sequence,this study has been conducted.First,the definition of the strong aftershock has been given.It is pointed out that there is a difference in the strong aftershock duration time between the main shock type sequence and the strong earthquake swarm sequence.After dividing the three cases,i.e.,a strong aftershock duration time larger than 1 day,smaller than 1 day,and no strong aftershock occurred in a main shock type sequence by using the pattern recognition method,we gave the rough correlation relation between strong aftershock duration time and first large shock magnitude for two types of sequences.Finally,the judgment index and method of estimating strong aftershock duration times for different sequence types have been given. 相似文献
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在综合分析甘肃省东南部地震地质特征的基础上,利用模式识别方法判定未来地震危险区的可能位置.结果表明,本区易发生地震的地点与全新世断裂强烈活动段相吻合,从而提高了对未来地震危险区判定的可信度 相似文献
46.
强余震持续时间的早期估计 总被引:2,自引:0,他引:2
本研究旨在解决地震序列中强余震持续时间的早期估计问题。文中首先给出了强余震的震级定义,指出:主震型与强震群型序列的强作震持续时间存在差异。使用模式识别方法对主震型序列中强余震持续时间大于1天,小于1天及无强余震等3种情况进行划分之后,给出了两类序列的强余震持续时间与序列和第一震震级的粗略相关关系。 相似文献
47.
近断层地震动对地表结构物造成严重的破坏,它具有明显的方向性和脉冲型特征. 在速度时程中含有大幅值、长周期的脉冲波,对结构响应影响很大. 为简化计算和分析的需要,在既有的等效速度脉冲模型的基础上,建议了较为合理等效速度脉冲模型. 在充分收集脉冲型近断层地震记录的基础上,对等效速度脉冲模型的脉冲周期、脉冲强度及卓越脉冲数等参数进行了研究,并与以往研究者的结果进行比较,以利于近断层区结构的抗震设计. 相似文献
48.
Gürcan Büyüksalih Güven Koçak Murat Oruç Hakan Akçin Karsten Jacobsen 《The Photogrammetric Record》2004,19(107):200-218
TK-350 stereo-scenes of the Zonguldak testfield in the north-west of Turkey have been analysed. The imagery had a base-to-height ratio of 0·52 and covered an area of 200 km × 300 km, with each pixel representing 10 m on the ground. Control points digitised from 1:25 000 scale topographic maps were used in the test. A bundle orientation was executed using the University of Hanover program BLUH and PCI Geomatica OrthoEngine AE software packages. Tests revealed that TK-350 stereo-images can yield 3D geopositioning to an accuracy of about 10 m in planimetry and 17 m in height. A 40 m resolution digital elevation model (DEM) was generated by the PCI system and compared against a reference DEM, which was derived from digitised contour lines provided by 1:25 000 scale topographic maps. This comparison showed that accuracy depends mainly on the surface structure and the slope of the local terrain. Root mean square errors in height were found to be about 27 and 39 m outside and inside forested areas, respectively. The matched DEM demonstrated a systematic shift against the reference DEM visible as an asymmetric shift in the frequency distribution. This is perhaps caused by the presence of vegetation and buildings. 相似文献
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Automated reconstruction of building objects from aerial images is a complex problem due to the diversity of buildings as well as noise and low contrast of images, which are the results of distant photography, atmospheric effects and poor illumination. In this paper, a semi-automated approach to the reconstruction of parametric building models from aerial images is presented, which works with line segments extracted from the image. The model is selected interactively from a library of parametric models. A perceptual grouping technique is used to select the most significant image lines in terms of relations such as proximity and parallelism. Model lines are searched for the same relations as in the grouped image lines, and the corresponding lines undergo a matching procedure, which determines whether or not a match can be found between the given model and image lines. An experiment with aerial images of flat-roof and gable-roof buildings is shown and its results indicate the robustness and efficiency of the proposed approach. 相似文献