东沙海区浅层剖面资料的改进处理

针对浅地层剖面仪在东沙海区采集的浅层剖面资料中出现的随机干扰、大值干扰等问题,通过去噪处理手段进行了有效的压制,消除了干扰波对原始资料的污染;针对由于间隔性采集和处理对原始资料造成的时间延迟现象,通过时移校正方法进行了处理;针对剖面中炮号与相应导航文件中的FIX号不存在对应关系的情况,通过提取道头时间、导航时间并在FOCUS模块中编写相应程序,将剖面中炮号与FIX号的关系建立起来。改进处理后的浅层剖面资料为地质分析与解释提供了较好的基础资料。     

Automatic building extraction from very high-resolution image and LiDAR data with SVM algorithm

Recent developments in the field of remote sensing have introduced new sensor technologies in usage of LiDAR, SAR, and high-resolution optical data. Classification performance is expected to increase through combining these various data sources. The purpose of this study is to develop a new approach for automatic extraction of buildings in urbanized and suburbanized areas. For this purpose, multi-feature extraction process including the spatial, spectral, and textural features were conducted on the very high spatial resolution multispectral aerial images and the LiDAR data set. SVM algorithm was trained by using this multi-feature data, and the classification was performed. After the classification of building and non-building, objects were extracted with high accuracy for the test areas. As a result, it has been proven that multi-features derived from combination of optical and LiDAR data can be successfully applied to solve the problem of automatic detection of buildings by using the proposed approach.     

遥感图象处理与信息提取方法的研究

在图象预处理中．为了研究不同处理方法的效果．分别采用了灰度变换、图象平滑和图象锐化等方法,经过比较发现,不同的增强方法对不同的特征地物的效果有明显的差异;在图象信息提取时,分别使用最小距离法、比值法和组合比等方法．采用不同波段的图象组合进行运算,可以依次突出不同的地物信息．从而达到了信息自动识别的目的。     

探地雷达图像数据处理及应用研究

对探地雷达数据构成及干扰来源进行了分析,利用均值法去除背景噪声;运用HIL-BERT变换数据处理技术得到雷达图像的瞬时振幅、瞬时相位和瞬时频率等瞬时剖面图像,以提高图像的分辨力,增强目标识别的准确性。通过对工程实际探地雷达图像数据的处理,验证了方法的有效性。     

青海沟里园以地区地球化学测量信息提取与远景区划分

青海沟里园以地区位于东昆仑造山带的东段,根据水系沉积物地球化学测量信息提取发现多个矿床（点）,具有较好的找矿潜力。文章以沟里园以地区1：5万水系沉积物地球化学测量数据为研究对象,对数据剔值处理来确定元素异常下限并圈定单元素异常与组合异常,结合区内地质找矿特征对圈定的元素异常进行解释与推断。通过对元素地球化学特征、元素组合特征及单元素异常特征综合研究表明,Au、Ag、Pb、Zn、Cu、Co等元素与成矿关系密切;提取出2个元素组合,确定套合性和相关性好的Ag-Bi-Pb-Zn与Cu-Co组合异常为预测对象;结合区内成矿地质条件,进一步圈定3个找矿远景区。     

Attenuation of random noise in GPR data by image processing

Random noise in ground penetrating radar (GPR) data affects the signal-to-noise ratio, blurs the details, and complicates reconnaissance of the useful information. Many methods with different advantages and disadvantages have been proposed to eliminate or weaken the random noise. We have reviewed basic principles of various signal processing techniques including the curvelet transform (CT), non-local mean (NLM), median, and mean filters to remove the random noise and compared their performances using synthetic and actual GPR data. The performances of the four filters were analyzed on synthetic GPR data both in time and frequency domains. On noisy synthetic data, results indicate that the CT filter performs better than NLM, mean, and median filters at attenuating random noise and improving S/N of the GPR data. On the real data, the performance of only the NLM and CT filters was investigated. Comparing the results clearly shows the CT filter robustness for the random noise attenuation and simultaneously its signal preservation.     

基于ETM数据的庞西垌地区断裂信息提取

针对庞西垌地区植被高覆盖特征,主要选用ETM+数据,结合DEM数据,采用正向主成分分析、波段比值、多波段信息合成等处理方法,提取与成矿控矿相关的线状、环状构造信息,结合该区相关地质资料,实现研究区构造综合解译.     

用ASTER数据进行不同类型矿床蚀变异常提取研究

文章在利用多光谱ASTER数据进行不同矿床蚀变异常提取的地质和波谱前提的基础上，对东天山斑岩型Cu矿床、镁铁质岩型Cu-Ni矿床和矽卡岩型Pb-Zn矿床的羟基ASTER蚀变异常提取方法进行了研究；对于铁染异常，利用ASTER数据可提取的只有黄钾铁矾异常。对黄山东Cu-Ni矿及沙泉子Pb-Zn矿的蚀变分带现象进行了初步研究，其结果有助于区分矿床类型。此外还利用多光谱ASTER数据研究了识别某些矿物的可能性。     

Feature extraction for hyperspectral remote sensing image using weighted PCA-ICA

Principal component analysis (PCA) and independent component analysis (ICA) are linear feature extraction methods in terms of the second-order statistics and higher-order statistics and have good compatibility and complementarity. For the feature extraction of the hyperspectral remote sensing image, an approach of the combined PCA and ICA was followed in the real remote sensing classification applications. In this study, the weighted PCA-ICA method was introduced to extract the feature information from HJ-1A hyperspectral imager (HSI) image. And then the real airborne visible infrared imaging spectrometer (AVIRIS) image case was performed by the distance similarity measure. Experimental results on HJ-1A HSI and AVIRIS images indicate that the proposed method can get high average accuracy of 89.55% and kappa coefficient of 0.8101 than the typical methods under certain condition with a suitable number of eigenvectors and weighted values.     

A Study of the hydrogeological environment of the lishan landslide area using resistivity image profiling and borehole data

Resistivity Image Profiling (RIP) surveys was used to develop a lithological and hydrogeological model of the subsurface in the southeastern part of Lishan landslide area of central Taiwan. The bedrock consists of slate in the study area. Based on RIP and rock samples collected from boreholes results, three electrical strata are recognized: colluvium, the shear zone composed of shear gouges and shattered slate, and the undisturbed slate formation. The steep shear zone with resistivity ranging between 100 ~ 260 Ω-m, plays a crucial role in the local hydrogeological environment, because it forms a natural barrier which blocks and retains groundwater flowing down the slope. Groundwater will brim over the barrier when the water level is high. Thus the inclined groundwater table remains stable from long-term monitoring. It strongly indicates that the groundwater recharge is greater than that of discharge. Therefore, the shear zone can provide information about the optimum locations for draining the excess groundwater in-situ for slope stability consideration.

The curved basal surface of the colluvium and the weathered slate can also be discerned from the resistivity variations and boreholes data. A series of circular patterns may associate with the main slope failure which migrated upwards from the lower slope.     

Structural evolution of Bondoc–Burias area (South Luzon,Philippines) from seismic data

Recently acquired 2-D seismic profiles in the offshore area between Bondoc Peninsula and Burias Island, South Luzon, Philippines, are interpreted in the context of known structural styles observed onshore and in relation to paleo- and neo-tectonic regimes in the region. Two distinct seismic sequences can be distinguished relative to their structural style and tectonic significance. The top of a lower sequence shows strongly reflective properties. This unit, correlative to Late Oligocene to Early Miocene limestone bodies observed onshore in Bondoc Peninsula and Burias Island, is affected by intense to moderate superposed folding and thrust faulting. An upper sequence, correlative to a two-member turbiditic and shallower marine clastic deposit widely exposed in Bondoc Peninsula, is affected by thrust faulting and deformation associated with overturned tight folding. The onshore equivalents of these two seismic sequences form the core of a bent anticlinorium that twists from a NW–SE axis in onshore Bondoc into a N–S axis southwards into the southern tip of the peninsula, then back to a NW–SE axis in the offshore region further to the south. Overlying this structural core is a relatively less deformed sequence where syn-sedimentary half-grabens are still preserved in places. This complex structural style is the result of a series of several tectonic events occurring from the Eocene to the Present, involving carbonate build-up, deep water turbidite deposition, consequent compression (folding and faulting), and late-event half graben-controlled deposition. Some resulting structures are indicative of tectonic inversion processes (positive and negative) which may prove to be potentially favorable in the search for structural plays in the area.     

膨胀土裂隙图像处理及特征提取方法的改进

裂隙特征作为膨胀土裂隙研究的基础,其定量化描述有助于进一步研究裂隙对膨胀土工程性质的影响。以膨胀土平面裂隙为研究对象,使用数码摄影获取膨胀土裂隙图像,通过优化和改进裂隙图像处理方法及裂隙特征提取方法,获得膨胀土裂隙的各特征参数。对于裂隙图像处理方法,采用改进的局部阈值二值化方法,相比大津法能更好地将裂隙和背景区分开来,而通过标记连通区域的方法有效去除了裂隙二值图像中全局分布的细小杂点,同时,利用闭运算填充了裂隙图像中细小的孔洞和缺口,上述处理方法使裂隙二值图像更清晰可靠。对于裂隙特征提取方法,基于对裂隙端点和交点的快捷识别能力,选择了查找表方法作为裂隙条数统计的基础;改进了端点识别算法以去除毛刺,提高了裂隙长度统计的精度;采用改进的最小外接矩形算法进行裂隙宽度的统计,提高了计算精度,节省了计算时间;尝试采用玫瑰花图进行裂隙方向统计,更直观明了地分析裂隙方向及条数的变化规律。     

基于K-L变换和灰度共生矩阵下的桂西—滇东南地质构造遥感信息提取方法研究

桂西-滇东南是植被高覆盖区域,地质遥感信息相对于地表覆盖(植被)信息而言相对较弱.有效消除地表覆盖信息、突出地质遥感信息是遥感地质专题信息提取的瓶颈之一.本文运用K-L变换提取代表地质构造信息的成分波段,有效滤去地表覆盖信息;利用灰度共生矩阵、定向检测和环形滤波检测相结合的方法,并通过阈值设置,提取地质构造的遥感专题信息,从而达到实现计算机自动提取地质构造信息的目的.经过野外实地验证,结果表明:地质构造信息提取精度较高,特别是一些小的地质构造信息也能有效提取;但是环形地质构造信息没有有效提取,地表覆盖类型对地质构造信息的提取仍有较小影响.     

Structural setup of Ras Banas area,Red Sea,Egypt, as inferred from aeromagnetic data

This study deals with the evaluation of the structural setup of the Ras Banas area on the northwestern part of the Red Sea by using magnetic data. Different analyzing techniques were applied to achieve this goal including regional-residual separation, trend analysis, depth estimation, Euler deconvolution, horizontal gradient, analytic signal, and magnetic modeling. The results of these techniques were used to construct a deep-seated structural feature map.Lineament analysis indicates that the area was mainly affected by the NW, WNW, and NE tectonic trends. The magnetic modeling was performed along four profiles supported by Euler deconvolution, horizontal gradient, and analytic signal profiles. The modeled profiles show that the basement rocks composed of uplifted and down-faulted blocks at different depths as well as step-like structure. The basement rocks seem to be acidic in nature intruded by basic/ultrabasic dikes. Generally, the magnetic susceptibility ranges from 0.0003 to 0.04 cgs indicating acidic to basic/ultrabasic rock composition. The basement relief map shows an irregular basement surface, which varies greatly in depth from 1 to 5.6 km below sea level. The deep-seated structure map shows that the basement was highly affected by two main fault trends in the NW and NNE directions. The NW trending structures were intersected by younger left lateral NNE transform faults. These cross-faults dissect the area into a number of alternated and elongated blocks.     

LK地区滩海浅层地震资料处理关键技术

山东LK地区三维区块主要为海陆两栖带和浅海水域,地下勘探目标煤层埋藏浅,地震资料比较复杂。针对滩海浅层地震资料的特点及地质目标,利用SLS直达波二次定位技术,较好地解决了检波器的漂移问题,提高了浅层成像效果;运用子波校正技术,消除激发、接收因素造成的资料品质差异,实现了海陆资料的无缝拼接;采取两步法自适应反褶积,有效消除了海底鸣震;采用叠前时间偏移技术,很好地解决了浅海地区复杂构造的偏移成像问题。形成了一套适用于滩海地区浅层煤炭资源探查的地震资料处理技术,获得了具有高信噪比、高分辩率和高保真度的成果资料。     

成像测井数据处理中分辨率匹配及深度校正方法

成像测井由于分辨率高、信息量大而得到广泛应用。但其采样密度相当高,在深度校正数据预处理中,当与常规测井数据进行分辨率匹配时带来了困难,通常的插值方法都不能很好地解决这一问题。采用快速且精度较高的阿克玛(Akima)光滑等距插值方法,对常规测井自然伽马(GR)曲线进行插值处理,在此基础上采用相关分析方法,确定成像测井带测GR曲线的深度偏移量。结果表明,该方法能够快速地进行测井数据分辨率匹配及有效地校正成像测井曲线的深度误差,为进一步提高成像测井图像解释的精度奠定了基础。     

Utilizing image processing techniques in lithologic discrimination of Buwatah area, Western Arabian Shield

The main task of this article is the evaluation of the IHS color transformation fusion, color composite ratios, and principal component analysis techniques for lithologic discrimination of the basement rocks exposed at Buwatah area, Western Arabian Shield, Saudi Arabia. Landsat ETM+ images were prepared and used to perform this task using PCI Geomatica software. IHS fusion technique was conducted through four main processing steps: (1) registration of the multispectral image (7, 4, and 2 in RGB) to the panchromatic image and then resample it to the same spatial resolution as that of the panchromatic image; (2) transformation of the three multispectral bands from RGB to IHS space; (3) substitution of the intensity value from the high spatial resolution panchromatic band; and finally (4) back transformation to RGB. The band ratios 5/7, 3/1, and 4/3 displayed in RGB, respectively, were used to produce the color composite ratio image. The first principal component (PC1), the second principal component (PC2), and the third principal component (PC3), displayed in RGB, respectively, were used to construct the color composite principal component image. The resultant images successfully discriminated the exposed rock units in the study area and a lithologic map has been constructed that is subjected to precise field verification. The stratigraphy of the area under consideration starts with metavolcanics and associated volcaniclastics as an oldest rock unit, followed by granodiorite–diorite, pink granite, biotite granite, acidic and basic dykes, and Cenozoic volcanics. A new rock unit (biotite granite) has been introduced that was not represented in previous mapping of the considered sector. The biotite granite is verified by field and petrographical studies.     

基于IHS变换的重力异常与遥感影像融合的构造信息提取研究

本文以深部探测关键仪器装备野外实验与示范基地为例,利用影像融合技术进行地质构造信息的提取。在卫星遥感和重力异常数据空间配准的基础上,利用IHS数据融合方法,将重力异常与ETM+数据进行融合与分析。研究表明:一方面构造形迹在遥感图像及重力异常上的表征是存在差异性的,即其空间分布特征,另一方面通过卫星遥感在地表定位重力异常所反演的地质信息,能够为深部探测仪器装备野外实验选点提供科学的依据。     

Textural identification of basaltic rock mass using image processing and neural network

A new approach to identify the texture based on image processing of thin sections of different basalt rock samples is proposed here. This methodology uses RGB or grayscale image of thin section of rock sample as an input and extracts 27 numerical parameters. A multilayer perceptron neural network takes as input these parameters and provides, as output, the estimated class of texture of rock. For this purpose, we have use 300 different thin sections and extract 27 parameters from each one to train the neural network, which identifies the texture of input image according to previously defined classification. To test the methodology, 90 images (30 in each section) from different thin sections of different areas are used. This methodology has shown 92.22% accuracy to automatically identify the textures of basaltic rock using digitized image of thin sections of 140 rock samples. Therefore, present technique is further promising in geosciences and can be used to identify the texture of rock fast and accurate.