Common-offset depth migrations and traveltime tomography. January 1999. SEG Technical Program Expanded Abstracts. 10.1190/1.1888776. Authors: William Harlan. Retired.Apr 27, 2006 · The common depth point method of shooting in oil exploration provides a series of seismic traces which yield information about the substrata layers at one location. After normal moveout and static ...High-resolution common-depth-point reflectionprofiling: Field acquisition parameter design Ralph W. Knapp* and Don W. Steeples* ABSTRACT The results of a seismic reflection profiling exercise are strongly dependent upon parameters used in field recording. The choice of parameters is determined by objectives of the survey, available resources ...MULTICHANNEL COMMON DEPTH POINT (CDP) SEISMIC REFLECTION DATA Additional Atlantic Survey Lines Data Announcement 1980SE-BB. The National Geophysical Data Center (now the National Centers for Environmental Information) is making available CDP seismic reflection data for lines 18 through 38 from Atlantic coastal areas.Jan 30, 2020 · The Common Depth Point (CDP) Method is a seismic data acquisition and processing technique which transforms field recordings from seismic surveys into pseudo-cross-sectional images of the earth’s geologic layering beneath the survey line. Oct 19, 2014 · Kent, G. M., Harding, A. J. & Orcutt, J. A. Distribution of magma beneath the East Pacific Rise between the Clipperton transform and the 9° 17′ N Deval from forward modeling of common depth ...Jan 21, 2021 ... ... common, they ultimately have different goals and purposes. A point cloud is usually a collection of data points that form a shape, while a ...Mar 28, 2000 · Common-midpoint gather. Common-midpoint gathers CMP (also called common-depth point CDP) are required for velocity analyses, Normal Moveout Correction NMO and for stacking. The whole line can be sorted so that it is in order of increasing CDP points and also so that the traces are in the order of increasing offset for each CDP point. The maximum foldage obtained from a 48-channel common depth point (CDP) reflection survey with the geophone and shot point spacing of 50m and 100m res. GEOPHYSICS. Dear friends, In this blog more than 297 GATE and CSIR-NET (mainly Geophysics) Questions have been Solved with neat explanations.Scrum has become a popular project management framework used by businesses worldwide. Its flexible and iterative approach allows teams to efficiently manage complex projects. In th...Common depth point (CDP) reflection profiling. (a) A set of rays from different shots to detectors are reflected off a common point on a horizontal reflector. (b) The common depth point is not achieved in the case of a dipping reflector. From Kearey, Philip and Micheal Brooks, An Introduction to Geophysical Exploration. 2nd ed. Blackwell ...Abstract: The Common Depth Point (CDP) Method is a seismic data acquisition and processing technique which transforms field recordings from seismic surveys into pseudo-cross-sectional images of the earth's geologic layering beneath the survey line. Such images are the primary geophysical analysis tools used by explorationists to pinpoint likely … is called a common midpoint gather or a common reflection point gather, which, unfortunately, in industry is often called a common depth point gather. This termi- nology originated in the days when analytical methods usually modeled the earth as a stratified medium in which the reflection point, called the depth point, lay Typical studies have used profile views of walking, but human observers have a strong impression of depth if an oblique or frontal view is displayed (Bülthoff, ... About common image point tomography. CIP-tomo is a generalized reflection tomography method that uses residual moveout (RMO, residual curvature) analysis of prestack depth-migrated CIP gathers to update an initial model. Multiparameter (nonhyperbolic, general, or nonparametric) RMO is automatically estimated from offset vector tile or angle ... Common depth point (CDP) Common depth point (COP) recording, sometimes called common mid point (CMP), is a basic method in present day seismic exploration, whether that is the normal linear 2-D type or 3-D recording. However, to understand the concept fully, it is necessary to look back on the history Dictionary. : Common-depth point (CDP) { {#category_index:C|common-depth point (CDP)}} The reflecting point that is common to a subset of data. The use of this term …Abstract: In seismic imaging, common midpoint (CMP) gathers are collections of time-series data organized by source-receiver pairs having a common midpoint. CMP gathers have been used in geophysics to image the subsurface of the Earth and estimate wave velocity as a function of depth. According to the Van Cittert-Zernike (VCZ) theorem, if the signals …In order to overcome the noise problem and additionally to estimate earth velocity, the method of acquisition most commonly used is the Common-Mid-Point (CMP) method. The same method is also called Common-Depth-Point …Common Depth Point (seismic exploration) CDP: Chemical Dependency Professional: CDP: Colorado Democratic Party: CDP: Comprehensive Drilling Plan (Colorado Oil and Gas Conversation Commission) CDP: Candidate Development Program: CDP: Congressional District Programs (Falls Church, VA) CDP: City Development Plan: CDP: Sisters of …1. n. [Geophysics] In multichannel seismic acquisition where beds do not dip, the common reflection point at depth on a reflector, or the halfway point when a wave travels from a source to a reflector to a receiver.In the case of flat layers, the common depth point is vertically below the common midpoint.In the case of dipping beds, there is no common …Common-conversion-point binning. We learned in analysis of amplitude variation with offset that an incident P -wave is partitioned at a layer boundary into reflected and transmitted P - and S -wave components. Consider the raypath geometry in Figure 11.6-30a for an incident P -wave generated by the source S1 and a flat reflector.Oct 23, 2017 ... Common depth point defines as sum of traces whichCommon depth point ... Common Mid Point (CMP) Common Depth Point (CDP); 8. Common Midpoint ...Oct 19, 2014 · Kent, G. M., Harding, A. J. & Orcutt, J. A. Distribution of magma beneath the East Pacific Rise between the Clipperton transform and the 9° 17′ N Deval from forward modeling of common depth ...Nov 2, 2022 · Can't sign in? Forgot your username? Enter your email address below and we will send you your usernameDownload scientific diagram | (Left) Common offset; (right) common depth point. from publication: UAV for Landmine Detection Using SDR-Based GPR Technology | GPR and UAV | ResearchGate, the ...Sep 2, 2019 ... ... depth images of a point cloud from some positions, as shown . ... Open3D uses a camera model and notation that is common in computer vision.Download scientific diagram | (Left) Common offset; (right) common depth point. from publication: UAV for Landmine Detection Using SDR-Based GPR Technology | GPR and UAV | ResearchGate, the ...Timing comparisons show that this method is faster than the conventional FFT technique demonstrated by Gold and Rader. In addition, it permits a shorter word length, smaller memory size, and is well suited to seismic data processing. Application of this method to common-depth-point trace summation ('stacking') is illustrated.Nov 2, 2022 · The well‐known instability of Kunetz’s (1963) inversion algorithm can be explained by the progressive manner in which the calculations are done (descending from the surface) and by the fact that completely different impedances can yield indistinguishable synthetic seismograms. Those difficulties can be overcome by using an iterative …Overview. common-depth-point stack. Quick Reference. The sum of the traces of seismic reflection data, acquired from a roll-along survey, which correspond to the same common …Throughout history, many cultures have used different names to refer to the divine being that is known as God. Each of these names has its own unique meaning and significance. In t...This is called the Common Depth Point (CDP) method because the data is repeatedly recorded over increasing source to receiver offsets, but with the raypaths reflecting off the same depth location on each geological surface. The CDP gather shown in figure 7 (b) shows the recorded traces for all source / receiver pairs.MULTICHANNEL COMMON DEPTH POINT (CDP)SEISMIC REFLECTION DATA. Data Announcement 1976-R. * Third Data Set: Seismic data for Three Additional Atlantic Survey lines. As part of a program by the U.S. Geological Survey (USGS) to gain a better understanding of the general geologic framework of the Continental Shelf, Slope, and …The objective of the cooperative study was to utilize marine common-depth-point (CDP), digital, and multichannel techniques to locate a monoclinal flexure of the Cap au Gres Fault that earlier had been interpreted from land seismic data to be in the vicinity of Lock and Dam No 26 (Shannon and Wilson, 1980).Metode horizon based depth tomography untuk mengidentifikasi struktur pada lapangan “x” 2D pre stack depth migration (PSDM) common reflection angle migration (CRAM) menggunakan perangkat keras meliputi CPU (Central Processing Unit), computer 2 layar (30 inci) dengan system operasi linux (read head) milik perusahaan PT.Common-offset depth migrations and traveltime tomography. January 1999. SEG Technical Program Expanded Abstracts. 10.1190/1.1888776. Authors: William Harlan. Retired.Dec 14, 2021 ... Common depth cues the brain uses to perceive depth without stereo vision. And for bonus points, notice that the "cylinders" aren't actually ...Jan 6, 2024 · Cookies help us deliver our services. By using our services, you agree to our use of cookies.Jan 3, 2018 ... depth-point (CDP) location. The use of multiple azimuths greatly ... imaging, the resulting common offset, varying azimuth (COVA) gathers ...Are you ready to embark on an exhilarating gaming adventure? Look no further than Slope Game Online. This fast-paced and addictive game has taken the online gaming community by sto... views 3,536,275 updated. common depth point (CDP) In multichannel reflection profiling, the unique point on an individual reflector from which seismic reflection information is recorded in traces at different offsets. A set of traces containing information for one CDP is called a ‘CDP gather’, and the midway position between the shots and ... Audio bit depth. An analog signal (in red) encoded to 4-bit PCM digital samples (in blue); the bit depth is four, so each sample's amplitude is one of 16 possible values. In digital audio using pulse-code modulation (PCM), bit depth is the number of bits of information in each sample, and it directly corresponds to the resolution of each sample. Jan 21, 2020 · 1.点云数据转激光数据 (有一个包叫depthimage_to_laserscan)，来减少信息量。. (仿真的点云转激光貌似只是平面转换，没有进行投影映射) 2.如果高端一点就对分割出来的特定物体进行边缘提取，然后作为少量的pointcloud2数据传入. 3.限制点云数据的分辨率 (在gazebo中没有 ... Data Announcement 87-MGG-03. Approximately 2,233-km of 24-channel common depth point (CDP) seismic-reflection profiles for purchase from the National Geophysical Data Center (NGDC) (now the National Centers for Environmental Information (NCEI)) for the Pacific Outer Continental Shelf off northern California and Oregon. Techniques are described whereby multiple coverage of the subsurface is obtained. Detector spreads and shotpoints are arranged so that the channels representing common depth points are recorded with appreciably different horizontal distances between the shotpoints and detector stations. The channels which have a common reflection point are combined, or stacked, after appropriate corrections ... Seismic surveying is the most important of the three main types of geophysical prospecting. To understand this method, a review of the physical principles that govern the movement of acoustic or shock waves through layered media is necessary. Consider a source of acoustic energy at a point on the Earth’s surface. Nov 2, 2022 · The results of a seismic reflection profiling exercise are strongly dependent upon parameters used in field recording. The choice of parameters is determined by objectives of the survey, available resources, and geologic locality. Some simple modeling and/or a walkaway noise survey are helpful in choice of field parameters. Filtering data …Close mobile search navigation. Article navigation. Volume 51, Number 2The common-depth-point gather is conducted at angles of offset of less than 20-30 degrees such that assumptions concerning various elastic parameters: density, compressional wave velocity and shear-wave-velocity can be made which allow the application of linear fitting techniques to the gathered data. The sum of these coefficients corresponds ... Approximately 2,500 km of underway geophysical data, including 430 km of 24-channel common depth point (CDP) seismic-reflection data for purchase from the National Geophysical Data Center (NGDC) (now the National Centers for Environmental Information (NCEI)). The data were collected in the eastern equatorial Pacific Ocean offshore Nicaragua and ... Jumpstart your career! Learn from a vast source of knowledge, that you know you need, but couldn’t find anywhere. Dive deep into lighting, CG techniques, materials, color, design and archviz business. And look at it all from a wider perspective. Whether you want to understand a subject in depth or need a good portion of inspiration. CMP. 1. n. [Geophysics] In multichannel seismic acquisition, the point on the surface halfway between the source and receiver that is shared by numerous source-receiver pairs. Such …Fig. 1. Common events on a walkaway noise test reco rd. microcomputer for data acquisition and processing. High-resolution shallow reflection seismics can now be successfully applied to geological, engineering and environmental problems (e.g. Meekes et al. 1990, Pullan & Hunter 1990, Miller & Steeples 1994). The most commonly applied shallow reflection …Illustration of common depth point (often called common mid point). Arrivals on a seismic reflection record can be seen in figure 4. The receivers are arranged to one side of a shot, …Insular shelves are underwater landmasses surrounding islands. They are relatively shallow areas that extend from the low waterline, usually to a depth of about 100 fathoms, where ...MULTICHANNEL COMMON DEPTH POINT (CDP) SEISMIC REFLECTION DATA ADDITIONAL ATLANTIC SURVEY LINES Data Announcement 1979N-N. The National Geophysical Data Center (now the National Centers for Environmental Information) is making available additional CDP seismic reflection data (lines 7, 8, 11, 12, and 13).Sep 14, 2011 · G is for Gather. September 14, 2011 / Evan Bianco. When a geophysicist speaks about pre-stack data, they are usually talking about a particular class of gather. A gather is a collection of seismic traces which share some common geometric attribute. The term gather usually refers to a common depth point (CDP) or common mid-point (CMP) gather. Chapter. Full-text available. Jun 2022. Matteo Salonia. Christian Mueller. The article investigates multiform perceptions of Asia during the Cold War in the 1960s through the lenses of politics,...• CDP bases input traces on their common depth point number. Used primarily for CDP gathers. • SOURCE, SOU_XD, or SOU_YD bases input records on the sequential source number or changes in coordinates within the file. To be used primarily for shot gathers. • REC_XD, or REC_YD bases input ensembles on changes in their receiver coordinates.Pengelompokan tersebut dapat berupa : 1. Common Source Point (CSP) 2. Common Depth Point (CDP) Proposal kerja praktek PT. Elnusa Tbk 3. Common Offset 4. Common Receiver Ilustrasi berbagai trace gathering beserta respon seismiknya. Fig. Common mid-point (CMP) reflection profiling. (a) A set of rays from different shots to detectors reflected off a common depth point (CDP) on a horizontal reflector. (b) The common depth point is not achieved in the case of a dipping reflector. • In the case of horizontal layers, reflection events on each CMP gather are reflected fro ... Jun 28, 2023 · The common-depth-point (CDP) seismic-reflection method was used to delineate subsurface structure in a 3-m thick, 220-m deep coal zone in the Palau area of Coahuila, Mexico. An extensive series of walkaway- noise tests was performed to optimize recording pa- rameters and equipment. Reflection events can beWhen it comes to choosing a gas dryer for your home, size is an important factor. If you have limited space, a 27 inch depth gas dryer may be the perfect choice. Here are some tips...Chapter. Full-text available. Jun 2022. Matteo Salonia. Christian Mueller. The article investigates multiform perceptions of Asia during the Cold War in the 1960s through the lenses of politics,...Abstract: In seismic imaging, common midpoint (CMP) gathers are collections of time-series data organized by source-receiver pairs having a common midpoint. CMP gathers have been used in geophysics to image the subsurface of the Earth and estimate wave velocity as a function of depth. According to the Van Cittert-Zernike (VCZ) theorem, if the signals …First Online: 25 June 2021. 1013 Accesses. Part of the book series: Advances in Oil and Gas Exploration & Production ( (AOGEP)) Abstract. Seismic reflection events are caused by …The common-depth-point information is gathered for a plurality of incidence angles, (theta), of less than 20-30° such that assumptions concerning various elastic parameters, density, compressional-wave-velocity and shear-wave-velocity can be made which allow the application of linear fitting techniques to the gathered data. About common image point tomography. CIP-tomo is a generalized reflection tomography method that uses residual moveout (RMO, residual curvature) analysis of prestack depth-migrated CIP gathers to update an initial model. Multiparameter (nonhyperbolic, general, or nonparametric) RMO is automatically estimated from offset vector tile or angle ... Jan 3, 2018 ... depth-point (CDP) location. The use of multiple azimuths greatly ... imaging, the resulting common offset, varying azimuth (COVA) gathers ...Aug 27, 2016 · Time migration is a very close process to common-midpoint (CMP) stacking and, more recently, to zero-offset commonreflection- surface (CRS) stacking. In fact, Kirchhoff time migration operators can be readily formulated in terms of CRS parameters. In the nineties, several studies have shown advantages in the use of common-reflection-point (CRP ... Variasi desain akuisisi seismik 2D yang dianalisa pada penelitian ini adalah Common depth point Interval (CDP Interval), Fold Coverage, dan Far Offset. Target formasi yang dianalisa adalah Formasi Jatibarang bagian atas dengan kedalaman 1763 meter dan terletak pada domain waktu seismik 1000 ms. Download scientific diagram | (Left) Common offset; (right) common depth point. from publication: UAV for Landmine Detection Using SDR-Based GPR Technology | GPR and UAV | ResearchGate, the ... The subject method includes the gathering of common-depth-point information for a plurality of incidence angles, (theta) and estimating the linear coefficients (R /SUB pp/ . /SUB o/ and R /SUB pp/ ./sub 1/)of a linear function fitted to the amplitudes vs. sin/sup 2/ (theta) measured for each point of reflection. The objective of the cooperative study was to utilize marine common-depth-point (CDP), digital, and multichannel techniques to locate a monoclinal flexure of the Cap au Gres Fault that earlier had been interpreted from land seismic data to be in the vicinity of Lock and Dam No 26 (Shannon and Wilson, 1980).When it comes to choosing the right dryer for your home, there are many factors to consider. One of the most important is the size of the dryer. If you’re looking for a gas dryer, ...A high-resolution seismic-reflection survey was run on the Mississippi River using marine common-depth-point (CDP), digital, and multichannel techniques in an attempt to locate a possible fault that had been interpreted by others from magnetic and land seismic data to be in the vicinity of Lock and Dam No. 26. The geologic feature is commonly known in the …Common depth point (CDP) reflection profiling. (a) A set of rays from different shots to detectors are reflected off a common point on a horizontal reflector. (b) The common depth point is not achieved in the case of a dipping reflector. From Kearey, Philip and Micheal Brooks, An Introduction to Geophysical Exploration. 2nd ed. Blackwell ...To do this, use the Point File Information geoprocessing tool. Note: Point data can come in a variety of formats. Since XYZ data is one of the most common ...Common depth point (CDP) reflection profiling. (a) A set of rays from different shots to detectors are reflected off a common point on a horizontal reflector. (b) The common depth point is not achieved in the case of a dipping reflector. From Kearey, Philip and Micheal Brooks, An Introduction to Geophysical Exploration. 2nd ed. Blackwell ...Sep 2, 2019 ... ... depth images of a point cloud from some positions, as shown . ... Open3D uses a camera model and notation that is common in computer vision.Common depth point seismic prospecting is accomplished by sequentially producing seismic waves at transmitting locations spaced apart the distance A, and detecting resulting seismic waves at a first plurality of detecting locations along the traverse spaced apart a distance A from the transmitting location corresponding thereto and a second plurality of … Audio bit depth. An analog signal (in red) encoded to 4-bit PCM digital samples (in blue); the bit depth is four, so each sample's amplitude is one of 16 possible values. In digital audio using pulse-code modulation (PCM), bit depth is the number of bits of information in each sample, and it directly corresponds to the resolution of each sample. 1. Common-Depth Point Seismic Data: 24-Fold multichannel seismic data for 5 lines, 26 sections (full scale) available in plastic sepia, paper sepia, and blackline. 2. Other Geophysical Data: 3. Merged navigation, magnetics and bathymetric data are available in MGD77 format on 1 magnetic tape or CD-ROM.A high-resolution seismic-reflection survey was run on the Mississippi River using marine common-depth-point (CDP), digital, and multichannel techniques in an attempt to locate a possible fault that had been interpreted by others from magnetic and land seismic data to be in the vicinity of Lock and Dam No. 26. The geologic feature is commonly known in the …The results of a seismic reflection profiling exercise are strongly dependent upon parameters used in field recording. The choice of parameters is determined by objectives of the survey, available resources, and geologic locality. Some simple modeling and/or a walkaway noise survey are helpful in choice of field parameters. Filtering data before analog‐to‐digital …• CDP bases input traces on their common depth point number. Used primarily for CDP gathers. • SOURCE, SOU_XD, or SOU_YD bases input records on the sequential source number or changes in coordinates within the file. To be used primarily for shot gathers. • REC_XD, or REC_YD bases input ensembles on changes in their receiver coordinates.• CDP bases input traces on their common depth point number. Used primarily for CDP gathers. • SOURCE, SOU_XD, or SOU_YD bases input records on the sequential source number or changes in coordinates within the file. To be used primarily for shot gathers. • REC_XD, or REC_YD bases input ensembles on changes in their receiver coordinates.A steeply dipping crustal fault that extends from the surface near CDP (Common Depth Point) 150 to its truncation by the E reflectors at ~30 km depth near CDP 400 has been interpreted from the ...
Geophysics. J. Wheeler, M. Cheadle, in Reference Module in Earth Systems and Environmental Sciences, 2014 Abstract. Geophysics is the study of the physics of the Earth and its environment in space. One emphasis is the exploration of the Earth's interior using physical properties measured at or above the Earth's surface, together with mathematical …. Alight retirement
Of all the advances in the reflection seismic technique, surely none is more important nor has had greater impact than the invention of common-depth-point coverage, or simply, stacking. In concept, the procedure is very simple. The distance between seismic source and receiver is varied symetrically to survey the same subsurface point several times.MULTICHANNEL COMMON DEPTH POINT (CDP) SEISMIC REFLECTION DATA ADDITIONAL ATLANTIC SURVEY LINES Data Announcement 1979N-N. The National Geophysical Data Center (now the National Centers for Environmental Information) is making available additional CDP seismic reflection data (lines 7, 8, 11, 12, and 13).A steeply dipping crustal fault that extends from the surface near CDP (Common Depth Point) 150 to its truncation by the E reflectors at ~30 km depth near CDP 400 has been interpreted from the ...In recent years, electric scooters have gained immense popularity as a more sustainable and efficient mode of transportation. One such scooter that has caught the attention of many...Abstract: The Common Depth Point (CDP) Method is a seismic data acquisition and processing technique which transforms field recordings from seismic surveys into pseudo-cross-sectional …The deepest ocean in the world is the Pacific Ocean with an average depth of 13,740 feet. The deepest point in the Pacific Ocean is the Mariana Trench at 36,200 feet. The second-de... Fig. Common mid-point (CMP) reflection profiling. (a) A set of rays from different shots to detectors reflected off a common depth point (CDP) on a horizontal reflector. (b) The common depth point is not achieved in the case of a dipping reflector. • In the case of horizontal layers, reflection events on each CMP gather are reflected fro ... The common depth point stack. Abstract: The Common Depth Point (CDP) Method is a seismic data acquisition and processing technique which transforms field recordings …A common-depth-point (CDP) gather is defined by the industry and by common usage to be the same thing as a common-midpoint (CMP) gather. But in this book a distinction will be made. A CDP gather is a CMP gather with its time axis. 3-D views Different ways to view 3-D volumes. 3-D survey Name the views. 3-D survey Name the views Common Depth Point (CDP) didefinisikan sebagai jejak gelombang (trace) yang digabungkan, yang mana I. PENDAHULUAN memiliki koresponden refleksi bawah permukaan (subsurface) yang sama tapi memiliki perbedaan M etode seismik refleksi memberikan kontribusi besar dalam kegiatan eksplorasi seismik. The evolution of image-based depth estimation is shown in Fig. 1.In the early period, researchers estimated depth maps depending on depth cues, such as vanishing points [142], focus and defocus [138], and shadow [181].However, most of these methods were applied in constraint scenes [138], [142], [181].With the development of computer … Download scientific diagram | (Left) Common offset; (right) common depth point. from publication: UAV for Landmine Detection Using SDR-Based GPR Technology | GPR and UAV | ResearchGate, the ... Nov 5, 2021 · The performance of two popular migration methods—the Kirchhoff integral and reverse‐time migrations—is evaluated through applications to imaging complex structures using prestack shot records. The migration results from the Marmousi model data demonstrate that reverse‐time migration is more accurate than Kirchhoff migration in …Data Announcement 87-MGG-03. Approximately 2,233-km of 24-channel common depth point (CDP) seismic-reflection profiles for purchase from the National Geophysical Data Center (NGDC) (now the National Centers for Environmental Information (NCEI)) for the Pacific Outer Continental Shelf off northern California and Oregon.1. Common-Depth Point Seismic Data: 12- and 24-fold multichannel seismic data for 27 sections (full scale) available in plastic sepia, paper sepia and blackline. 2. Other Geophysical Data: 3.5 kHz and 12 kHz profiler records and magnetic profiles on 1 roll of 35-mm microfilm (No. 2098) 3. Merged digital navigation, magnetics and bathymetric ...In today’s fast-paced digital world, staying informed is more important than ever. With the abundance of news sources available online, it can be overwhelming to find a reliable an...Common Depth Point Method. The common depth point (CDP), often called the common reflection point or common image point, refers to the collection of seismic traces …Techniques are described whereby multiple coverage of the subsurface is obtained. Detector spreads and shotpoints are arranged so that the channels representing common depth points are recorded with appreciably different horizontal distances between the shotpoints and detector stations. The channels which have a common reflection point ….