application of seismic reflection method

For each shot, the weight of dynamite is 350–400 g. The shot interval is 10 m. Each shot record consists of 24 channels with a receiver interval of 5 m. The offset between the shot and the first receiver is 30 m. The recording length includes 2048 samples with a sampling rate of 0.4 ms. Data processing includes pre-processing, static correction, filtering, velocity analysis, NMO correction, stack, noise attenuation and depth migration. The shallow seismic exploration method has been used extensively in petroleum exploration and geological engineering, but whether or not it is suitable for solid-ore exploration is still uncertain since solid ore deposits are usually irregularly shaped. At the midsections, -12 m and -60 m, orebody number 5 consists of two segments of high-grade ore: one is located between exploration lines 7 and 8 and the other is located above -60 m, between exploration lines 10 and 12. Success is greatly increased if shots and phones are near or in the saturated zone. Based on the geological results presented above, we point out the possibility that gold orebodies may occur between lines 14 and 16 in the Yangji-Shan site. Geophysical Prospecting Center, China Earthquake Administration, Zhengzhou 450002, China; Cryptoexplosive breccias (NQδμ); 7. Each lens is about 20 m long and 5–8 m wide. Therefore, due to the complexity of the geological processes involved, in the course of exploration for solid mineral resources, especially gold and copper, there are several factors that must be very carefully considered. A multifold stack technique is adopted. There are two ENE-trending trunk fractures, F1 and FA. This study was supported financially by the research project Exploration and Evaluation for the Superior Mineral Resources in Xinjiang, China (no 2001BA609A-07) and the project Relationship between Palaeozoic Effluent Basalts in Contiguous Areas among Yunnan, Guizhou and Sichuan Provinces and Copper Metallogenesis, which is a sub-project of the CAS Knowledge Innovation Project Continental Lithospheric Extension in South China and its Metallogenesis. The theory is identical, but the acquisition and processing parameters are adjusted to provide a higher resolution at shallow depths. search for low velocity zones using reflection seismic, so that the vulnerable locations causing earthquakes in the area are obtained. In case of I=0, the ratio of the reflected energy of P-wave, E r, to the incident energy, E i, is given by: E r / E i I=0 The square root of the above relationship is called Reflection Coefficient, R. 1920: Practical seismic reflection methods developed. 3. A nonmathematical discussion of seismic methods and the differences between reflection, refraction, and borehole seismology are given. Unique features of the seismic reflection method applicable to shallow engineering, groundwater, and environmental projects are described and recent applications are illustrated. Journal of Discrete Mathematical Sciences and Cryptography: Vol. This section focuses on the tectono-metallogenic process, i.e. The interpretation is based on Heiland (1946). However, the accuracy of these geological interpretations is always affected by certain factors, for example, the arrangement of the field observation system, the method of primary data collection, the method of data processing and the selection of parameters. This is possibly a contact zone between cryptoexplosive breccias (or quartz dioritic porphyrites) and sedimentary strata. Below -450 m, a soft band extends downwards to -600 m. This is interpreted as an ore-bearing magmatic channel probably composed of ore-bearing cryptoexplosive breccias. Industrial drilling has verified the interpreted results for the gold orebodies at Yangji-Shan. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide, This PDF is available to Subscribers Only. Using basic geological observations, we attempt to interpret geologically the seismic profiles obtained, which show various lithological interfaces. Oil and gas exploration and engineering studies in water‐covered areas routinely use continuous seismic profiling techniques to obtain subsurface geologic information. Fault F1 had cut through the Silurian and Triassic systems by the end of the early Indosinian–early Yanshanian episode; a quartz diorite and quartz dioritic porphyrite zone about 20 km in length is exposed along the fault. Seismic stratigraphy represents a coherent method for the analysis of sedimentary basin fills. In the ore area, fault F1 is not only an ore-conducting structure but also the ore-hosting site, together with the surrounding secondary en échelon plumose fractures. This law is utilized in the seismic reflection method. They can be characterized as echoes. APPLICATION OF THE SEISMIC REFLECTION METHOD TO ABANDONED MINE DETECTION IN ÓBIDOS, PORTUGAL João Carvalho1, Luís Torres1, Carlos Galhano2 and Luís Mendes-Victor3 1 Instituto Geológico e Mineiro, Estrada da Portela-Zambujal, 2720-461 Amadora 2 Universidade Nova, Monte da Caparica, 2829-516 Caparica 3 Centro Geofísica Universidade de Lisboa, Rua da Escola Politécnica, 58, … In the following, various applications of the shallow seismic methods are demonstrated by a number of examples. 479-484. Applications . 95% of the water used for human production and living comes from groundwater. Seismic reflection is generally applicable to depths greater than 80 to 100 feet, and is widely used on land to map a variety of deep features (e.g., stratigraphy, faults). The primary application of the seismic-reflection method is the mapping of lateral continuity of lithologic units and, in general, detection of change in acoustic properties in the subsurface. Upper Devonian (D3); 4. The shallow seismic exploration method has been used extensively in petroleum exploration and geological engineering, but whether or not it is suitable for solid-ore exploration is still uncertain since solid ore deposits are usually irregularly shaped. Groundwater refers to the subsurface water that occurs beneath the water table in geological formation that are fully saturated. This velocity is di erent for di erent rocks and it is this di erence which is exploited in the seismic method. For instance, all ore-bearing drill holes are located to the north of fault F1, indicating a directional tectono-metallogeneic migration. With this in mind, three holes have been drilled to test our seismic results. The use of seismic reflection surveys for targets shallower than 30 m has not been widespread until the 1980’s, however. Middle-Lower Triassic (T2-T1); 3. Application to seismic records 4.1. In most cases a 12-channel system was used. Middle-Upper Silurian (S2, S3); 5. Geological sketch of the Yangji-Shan gold deposit. Application of seismic reflection techniques for imaging sedimentary hosted massive sulphide is relatively new and the few experiment carried out have are at local scale [3] In this report, we extend the work of [3] by applying seismic reflection surveys for detecting massive sulphide deposits in sediment hosted environment at larger scale were the deposit may be located within 5km or more. using seismic refraction, surface-wave methods) and the presence of geological layers due to their seismic reflectivity (e.g. These igneous rocks experienced intense compression and shearing. This fracture acted as an ore-conducting and magma-conducting structure in the ore area, as the gold ores and mineralization outcrop in the fracture zone. 1.1.3 This guide will focus on the seismic-reflection method as it is applied to the near surface. Depth to bedrock under each geophone was obtained using this method. Seismic survey is the geophysical method, which is most closely related to rock and soil mass properties, since seismic wave velocity varies with the main mechanical properties, such as Poisson’s ratios and others modules. In general, the fraction of an orebody that is revealed at different depths is strictly controlled by the regional structure (Zhai and Yao 1992, Chen et al 1999). The lack of a reliable method for estimating Q from reflection seismic data is an issue when utilizing the Q value for hydrocarbon detection. Current mining of the gold deposit is limited locally to the region between exploration lines 5–14. APPLICATION OF THE SEISMIC REFLECTION METHOD TO ABANDONED MINE DETECTION IN ÓBIDOS, PORTUGAL João Carvalho1, Luís Torres1, Carlos Galhano2 and Luís Mendes-Victor3 1 Instituto Geológico e Mineiro, Estrada da Portela-Zambujal, 2720-461 Amadora 2 Universidade Nova, Monte da Caparica, 2829-516 Caparica 3 Centro Geofísica Universidade de Lisboa, Rua da Escola … 4. The weak zone in the subsurface structure can be modeled by using seismic reflection method based on the wave propagation properties that can reflect in a certain Seismic‐reflection profiling also was used to determine the extent and thickness of recent lake‐bottom deposits in two Connecticut lakes. Oxford University Press is a department of the University of Oxford. But, in using reflection seismology for oil and gas exploration, we have to deploy some kind of an acceptable energy source on the surface of the Earth and … The seismic-reflection method, a powerful geophysical exploration technique that has been in widespread use in the petroleum industry for more than 60 years, has been used increasingly since 1980 in applications shallower than 30m. The drilling data can be used to divide the bedrock lithology and confirm the geophysical results. For this reason, it has become the method of choice for the subsurface investigation of sedimentary basins, particularly for petroleum exploration. The successful application of the shallow seismic exploration method to the Yangji-Shan gold deposit in south China demonstrates that the determination of subsurface structure and potential orebodies is possible using this technique. The width of the intrusion increases gradually downwards and is also sack-like; it clearly intrudes into the structural crush zone. Seismic reflection is generally applicable to depths greater than 80 to 100 feet, and is widely used on land to map a variety of deep features (e.g., stratigraphy, faults). Moreover, interlayered crush zones and lateral fractures of the trunk faults are also well developed. By placing a seismic source in one well and receivers in another well, a seismic velocity model between the two wells can be constructed using tomographic techniques, and a reflection image can be obtained by processing the reflected arrivals. Additionally, since the 1980’s, significant strides have been made in both near-surface seismic reflection surveying and in the development of shallow-seismic refraction methods. ENE-to NE-trending fractures are predominant in the ore area with minor NW- and near-NS-trending faults. Seismic methods can provide valuable information of the subsurface, such as the seismic velocity structure of the geology (e.g. Seismic refraction is exploited in engineering geology, geotechnical engineering and exploration geophysics. 21, Application of Modern Optimization Algorithm in Management Science, pp. A heterogeneous approach without nodes at the interface is chosen to solve the problem in heterogeneous media. In this method the block matching algorithm is helpful for the recovery of seismic events because the texture blocks sharing the same reflection events are the most similar. Reflection seismology is used extensively in a number of fields and its applications can be categorised into three groups, each defined by their depth of investigation: The primary application of the seismic-reflection method is the mapping of lateral continuity of lithologic units and, in general, detection of change in acoustic properties in the subsurface. It states that “the angle of incidence is equal to the angle of reflection”. Tertiary red sandstone–conglomerates developed in the south-eastern area. The method is applied to seismic waves propagation problems, specifically to the problem of reflection and transmission of plane waves in heterogeneous media. In the northern section of the profile, a concealed sack-shaped pluton is located between -400 m and -600 m, forming a clear boundary with the wall rocks. The seismic profiles indicate the possible existence of other cryptoexplosive breccias (or quartz dioritic porphyrites) at -600 m, where the contact region between the inferred igneous rocks and the wall rocks clearly contains a crush zone. The depth scale is in metres and the horizontal axis shows the CDP number at intervals of 2.5 m. Shallow seismic section interpretation images of exploration line JB in the Yangji-Shan gold deposit (exploration line 14). The method requires a controlled seismic source of energy, such as dynamite, a specialized air gun or a seismic vibrator, commonly known by the trademark name Vibroseis. Surveys along 90 kilometers of river channels in the Sarasota‐port Charlotte, Florida, area defined in detail the stratigrapahy and continuity of the shallow aquifers. The seismic reflection method is a powerful technique for underground exploration that has been in use for over 60 years (see Waters, 1987; Dobrin, 1976; Coffee% 1978). 4. The basic principle of the seismic reflection technique application is to measure the time taken for a seismic wave that travels from a source down into the ground where it is reflected back to the surface where it can be detected by a receiver (geophone): The magmatic channels act as passages for the migration of ore-bearing fluids and the crush zones provide space for gold precipitation. This method was used as reconnaissance to locate the bedrock valleys. Seismic reflection is ideal for mapping geology at depths exceeding 50 m. Deep seismic reflection surveying is the most advanced technique in geophysics today, thanks to its application on a huge scale for oil and gas exploration. Geographically, this is about 2 km east of Rui-Chang County, Jiangxi Province. It also provides more accurate velocity parameters determined from a common-midpoint gather. The shallow seismic exploration procedure is principally divided into the following three stages: data acquisition, processing and interpretation. The detailed procedure for data processing is summarized in figure 2. Application of an undulatory method of reflection seismics to the biomedical field September 2020 : Physical Review Applied publishes the article "Seismic Imaging Method for Medical Ultrasound Systems" where the CRS4 Imaging and Numerical Geophysics group successfully validates the idea of applying an undulatory method of reflection seismics to the biomedical field . Seismic reflection is ideal for mapping geology at depths exceeding 50 m. Deep seismic reflection surveying is the most advanced technique in geophysics today, thanks to its application on a huge scale for oil and gas exploration. These features extend from -100 m to -1200 m. The geological interpretation of the seismic profile between lines 14 and 15 indicates that a crush zone exists in the contact region above -450 m between the Permian–Triassic strata and a quartz dioritic porphyrite intrusion, and the width of this crush zone is small. In this research the seismic reflection method has been used and studied to address problems associated with hardrock settings. Application of Seismic Reflection Surveys to Detect Massive Sulphide Deposits in Sediments-Hosted Environment Okan Evans Onojasun Department of Exploration Geophysics, Curtin University of Technology Abstract: Seismic reflection techniques, the most widely used geophysical method for hydrocarbon exploration For a more rigorous discussion of refraction and reflection seismology, visit An Introduction to Geophysical Exploration Check out equipment and seismic refraction applications in industry at Geosphere Inc. Lithoprobe is a Canadian program to study North American continental crust using refraction seismology as one of many exploration methods. 2. Guanghao Chen, Guanghe Liang, Deru Xu, Qiaosong Zeng, Shouhui Fu, Xiangrong Wei, Zhuanli He, Gonggu Fu, Application of a shallow seismic reflection method to the exploration of a gold deposit, Journal of Geophysics and Engineering, Volume 1, Issue 1, March 2004, Pages 12–16, https://doi.org/10.1088/1742-2132/1/1/002. Seismic method is one of the main tools of assessing fault activity. In figure 4, the discontinuous extension of different lithologic layers, all of which converge towards the current mining sites (at the northern end of the profiles), suggests the existence of a magmatic channel. Orebody (Au); 9. The application of this shallow seismic exploration method to the Yangji-Shan gold deposit in south China is, however, an example of a successful attempt to determine subsurface structure and find potential orebodies using the technique. Application of Seismic Reflection Surveys to Detect Massive Sulphide Deposits in Sediments-Hosted Environment Okan Evans Onojasun Department of Exploration Geophysics, Curtin University of Technology Abstract: Seismic reflection techniques, the most widely used geophysical method for hydrocarbon exploration Later tectonic activity along fault F1 resulted in the structural deformation of the orebodies and might have displaced the existing orebodies into several segments. Multiple-well techniques. Application of the three-component shallow seismic reflection method to probing buried active faults: LIU Bao-Jin 1, ZHAO Cheng-Bin 1, FENG Shao-Ying 1, YANG Xiao-Ping 2, HE Yin-Juan 1, LI Wen 1, ZUO Ying 1, KOU Kun-Peng 1: 1. In some cases, seismic patterns can be identified with depositional systems, unconformities, channels, and other features. Conclusi on The seismic reflection survey method has been. FA is still active in the Tertiary and along the fracture zone where the Tertiary basaltic magmas erupted. The application of this shallow seismic exploration method to the Yangji-Shan gold deposit in south China is, however, an example of a successful attempt to determine subsurface structure and find potential orebodies using the technique. In the seismic refraction method, the geophones are placed regularly on a straight line from the impact point, and the arrival time of the first shock wave is recorded. But now, the pollution degree of groundwater resources is serious, which is a serious threat to human. In interpretation of seismic data the resolution and smoothness of the envelope of the seismic trace is an important property to have. An application of a combined refraction-reflection seismic method to a landslide study / BALIA R.; DEIDDA G. P.; RANIERI G.. - (1996), pp. The drilling data indicate that other new industrial orebodies exist in the Yangji-Shan gold deposit. Typical applications of seismic reflection include: For more information, please contact our Ground Survey Team. It is clear that a volcanic channel exists adjacent to exploration lines 8–12. 1.1.3 This guide will focus on the seismic-reflection method as it is applied to the near surface. successful in many projects in coal area, such as - Coal exploration on shallow and deep - Imaging of structure in the subsurface of the coal mine area. The seismic reflection method involves inducing a seismic wave into the earth and recording the waves that are reflected from sub-surface layers. This paper describes a case study in which the shallow seismic exploration method was used to investigate the subsurface structure of the Yangji-Shan gold deposit in Jiangxi Province, south China. The sedimentary rocks experienced strong later silicification in the ore area, either as a result of the gold mineralization process or the emplacement of quartz dioritic porphyrites. 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