Map displays from an interactive interpretation

Geophysics ◽  
1986 ◽  
Vol 51 (10) ◽  
pp. 1999-2006 ◽  
Author(s):  
J. I. Denham ◽  
H. Roice Nelson
Keyword(s):  
Three Dimensional ◽  
Seismic Interpretation ◽  
Seismic Survey ◽  
Two Dimensional ◽  
Seismic Surveys ◽  
Mapping Techniques ◽  
Gippsland Basin

Map displays built during interactive seismic interpretation provide information not obtainable with traditional mapping techniques. Several map displays derived from the 1983 interactive interpretation of a Gippsland Basin three‐dimensional (3-D) seismic survey are presented below. Similar map display results have since been obtained with the interactive interpretation of two‐dimensional (2-D) seismic surveys. These types of mapping results are among the most important contributions of interactive interpretation procedures.

Using relative geologic time to constrain CNN-based seismic interpretation and property estimation

Geophysics ◽  
2021 ◽  
pp. 1-44
Author(s):  
Aria Abubakar ◽  
Haibin Di ◽  
Zhun Li
Keyword(s):  
Large Scale ◽  
Three Dimensional ◽  
Seismic Interpretation ◽  
Seismic Survey ◽  
Geologic Time ◽  
Seismic Amplitude ◽  
Property Estimation ◽  
Constrained Learning ◽  
Seismic Amplitudes ◽  
Multiplicative Regularization

Three-dimensional seismic interpretation and property estimation is essential to subsurface mapping and characterization, in which machine learning, particularly supervised convolutional neural network (CNN) has been extensively implemented for improved efficiency and accuracy in the past years. In most seismic applications, however, the amount of available expert annotations is often limited, which raises the risk of overfitting a CNN particularly when only seismic amplitudes are used for learning. In such a case, the trained CNN would have poor generalization capability, causing the interpretation and property results of obvious artifacts, limited lateral consistency and thus restricted application to following interpretation/modeling procedures. This study proposes addressing such an issue by using relative geologic time (RGT), which explicitly preserves the large-scale continuity of seismic patterns, to constrain a seismic interpretation and/or property estimation CNN. Such constrained learning is enforced in twofold: (1) from the perspective of input, the RGT is used as an additional feature channel besides seismic amplitude; and more innovatively (2) the CNN has two output branches, with one for matching the target interpretation or properties and the other for reconstructing the RGT. In addition is the use of multiplicative regularization to facilitate the simultaneous minimization of the target-matching loss and the RGT-reconstruction loss. The performance of such an RGT-constrained CNN is validated by two examples, including facies identification in the Parihaka dataset and property estimation in the F3 Netherlands dataset. Compared to those purely from seismic amplitudes, both the facies and property predictions with using the proposed RGT constraint demonstrate significantly reduced artifacts and improved lateral consistency throughout a seismic survey.

THREE-DIMENSIONAL DATA COLLECTION AND PROCESSING

1978 ◽  
Vol 18 (1) ◽  
pp. 116
Author(s):  
E. G. Selby
Keyword(s):  
Data Collection ◽  
Seismic Data ◽  
Signal To Noise Ratio ◽  
Three Dimensional ◽  
Depth Map ◽  
Seismic Survey ◽  
Seismic Exploration ◽  
Two Dimensional ◽  
Additional Advantage ◽  
Information Giving

There are many limitations in the ultimate accuracy of a conventional two dimensional seismic survey. One of the most important of these is that, in general, a prospect is not a two dimensional model but a three dimensional one. For a complete interpretation of a prospect area the final result should be a migrated time or depth map. With limited sampling (a seismic grid typically consists of loops with dimensions at least 1 km by 1 km) it is necessary to interpolate grid points to allow map migration and this method has inherent inaccuracies.The three dimensional seismic exploration technique is designed to provide a sufficiently close sampled grid of seismic traces, typically with a line and depth point spacing as close as 50-100 m, to allow the seismic data itself to be migrated three dimensionally. This allows the interpreter to work with migrated seismic sections and to contour directly the migrated map.Several techniques exist to allow practical and economic collection of seismic data to provide this close sampling. These techniques can be adapted to various terrain and cultural conditions.The main advantages of three dimensional data collection are correct imaging of the seismic information giving true vertical reflection time sections and improved signal-to-noise ratio due to the increased fold inherent in the three dimensional migration process. The additional advantage to the interpreter is that the data has a sampling which gives a line intersection at each depth point in the prospect.

3D seismic survey at the Millennium uranium deposit, Saskatchewan, Canada: Mapping depth to basement and imaging post-Athabasca structure near the orebody

Geophysics ◽  
2012 ◽  
Vol 77 (5) ◽  
pp. WC245-WC258 ◽  
Author(s):  
Niklas Juhojuntti ◽  
Garnet Wood ◽  
Christopher Juhlin ◽  
Clare O’Dowd ◽  
Peter Dueck ◽  
...  
Keyword(s):  
Hydrothermal Alteration ◽  
Uranium Deposit ◽  
Three Dimensional ◽  
Seismic Interpretation ◽  
Primary Objective ◽  
Mine Planning ◽  
Seismic Survey ◽  
Seismic Image ◽  
Uranium Exploration ◽  
Static Corrections

Three-dimensional seismic reflection measurements have been used to assist mine planning at the Millennium uranium deposit, Canada. The deposit is located within the crystalline basement, separated from the overlying Athabasca Basin sediments by an unconformity potentially associated with significant fluid flow. The primary objective of the [Formula: see text] survey was to image the unconformity and possible post-Athabasca deformation structures in and around the deposit. Clear unconformity reflections are observed within most of the survey area, although there are amplitude variations due to complex geology, including intense hydrothermal clay alteration around the deposit. Finite-difference modeling indicates that the wide-angle character of the unconformity reflections is due to a gradual velocity increase at the unconformity. The reflections are obscured by large time delays, due to Quaternary sediments covering the area, making refraction static corrections crucial. The seismic interpretation shows large variations in the unconformity depth (from approximately 430 to 650 m), indicating a pronounced basement depression that coincides with a gravity low. Reflections from the unconformity are vague within the depression, especially in the vicinity of the deposit. Although the orebody is not directly visible in the seismic image, there is a lack of reflectivity coincident with the alteration surrounding the mineralization. We also observed reflections which likely originate at the contact between the altered and fresh basement rock located beneath the deposit. The seismic data further indicate post-Athabasca faults in the vicinity of the orebody. Based on the initial seismic interpretation, the depth of the crown pillar was adjusted and the mine infrastructure moved away from areas interpreted to be affected by the intense hydrothermal alteration surrounding the deposit. The capability to image the unconformity, post-Athabasca structure, and hydrothermal alteration also highlights the potential use of seismic surveys in uranium exploration.

Field appraisal with three‐dimensional seismic surveys offshore Trinidad

Geophysics ◽  
1982 ◽  
Vol 47 (2) ◽  
pp. 177-195 ◽  
Author(s):  
Robert M. Galbraith ◽  
Alistair R. Brown
Keyword(s):  
Three Dimensional ◽  
Seismic Survey ◽  
Seismic Surveys ◽  
Multiple Attenuation ◽  
Fault Block ◽  
Geophysical Interpretation ◽  
Complex Fault ◽  
Exploration Risk ◽  
Petroleum Company ◽  
Oil Company

A consortium comprising Texaco Trinidad Inc., Trinidad and Tobago Oil Company Ltd., and Trinidad‐Tesoro Petroleum Company Ltd. commenced exploration in the South East Coast Consortium block offshore Trinidad in 1973. After four years of intensive exploration, a gas/condensate discovery was announced in early 1977 on the Pelican prospect. Later that year, in anticipation of the possible future need to site drilling/production platforms, a three‐dimensional (3-D) seismic survey was recorded over the prospect. This survey resulted in improvements in seismic record quality, multiple attenuation, and fault resolution. A coordinated geologic‐geophysical interpretation based on the 3-D seismic survey, a reevaluation of log correlations, and the use of seismic logs differed significantly from earlier interpretations. Because of this, it is anticipated that development of the field will need to be initiated in a different fault block from that previously envisioned. A second 3-D survey contiguous to the Pelican survey was recorded in 1978 over the Ibis prospect. Results show significant data enhancement in the deeper part of the section and improved fault resolution relative to previous two‐dimensional (2-D) control. The 3-D interpretation has revealed a much more complex fault pattern than originally mapped. Separate fault blocks will have to be individually evaluated, thus greatly increasing exploration risk.

High Resolution Microscopy of Multi-Layered Biological Crystals

1982 ◽  
Vol 40 ◽  
pp. 80-83
Author(s):  
H.A. Cohen ◽  
T.W. Jeng ◽  
W. Chiu
Keyword(s):  
High Resolution ◽  
Low Dose ◽  
Three Dimensional ◽  
Data Interpretation ◽  
Two Dimensional ◽  
Biological Objects ◽  
Density Maps ◽  
Density Map ◽  
Complex Crystal ◽  
High Resolution Microscopy

This tutorial will discuss the methodology of low dose electron diffraction and imaging of crystalline biological objects, the problems of data interpretation for two-dimensional projected density maps of glucose embedded protein crystals, the factors to be considered in combining tilt data from three-dimensional crystals, and finally, the prospects of achieving a high resolution three-dimensional density map of a biological crystal. This methodology will be illustrated using two proteins under investigation in our laboratory, the T4 DNA helix destabilizing protein gp32*I and the crotoxin complex crystal.

Instrumentation For Quantitative Microscopy

1977 ◽  
Vol 35 ◽  
pp. 206-209
Author(s):  
B. Ralph ◽  
A.R. Jones
Keyword(s):  
Volume Fraction ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Automatic Data ◽  
Phase Volume Fraction ◽  
Statistical Confidence ◽  
Resultant Data ◽  
Automatic Data Collection ◽  
Third Dimension ◽  
Evolution Of Microstructure

In all fields of microscopy there is an increasing interest in the quantification of microstructure. This interest may stem from a desire to establish quality control parameters or may have a more fundamental requirement involving the derivation of parameters which partially or completely define the three dimensional nature of the microstructure. This latter categorey of study may arise from an interest in the evolution of microstructure or from a desire to generate detailed property/microstructure relationships. In the more fundamental studies some convolution of two-dimensional data into the third dimension (stereological analysis) will be necessary.In some cases the two-dimensional data may be acquired relatively easily without recourse to automatic data collection and further, it may prove possible to perform the data reduction and analysis relatively easily. In such cases the only recourse to machines may well be in establishing the statistical confidence of the resultant data. Such relatively straightforward studies tend to result from acquiring data on the whole assemblage of features making up the microstructure. In this field data mode, when parameters such as phase volume fraction, mean size etc. are sought, the main case for resorting to automation is in order to perform repetitive analyses since each analysis is relatively easily performed.

A linearity test for thick specimens imaged by HVEM over a 180° angular range

1991 ◽  
Vol 49 ◽  
pp. 552-553
Author(s):  
Yu Liu
Keyword(s):  
Phase Contrast ◽  
Three Dimensional ◽  
Angular Range ◽  
Two Dimensional ◽  
Back Projection ◽  
Line Integral ◽  
Exponential Law ◽  
Transmission Electron ◽  
Absorption Law ◽  
Linearity Test

The image obtained in a transmission electron microscope is the two-dimensional projection of a three-dimensional (3D) object. The 3D reconstruction of the object can be calculated from a series of projections by back-projection, but this algorithm assumes that the image is linearly related to a line integral of the object function. However, there are two kinds of contrast in electron microscopy, scattering and phase contrast, of which only the latter is linear with the optical density (OD) in the micrograph. Therefore the OD can be used as a measure of the projection only for thin specimens where phase contrast dominates the image. For thick specimens, where scattering contrast predominates, an exponential absorption law holds, and a logarithm of OD must be used. However, for large thicknesses, the simple exponential law might break down due to multiple and inelastic scattering.

An Image Reconstruction System Applied to High Voltage Microscopy

1975 ◽  
Vol 33 ◽  
pp. 292-293
Author(s):  
D. E. Johnson
Keyword(s):  
High Voltage ◽  
Prior Information ◽  
Block Diagram ◽  
Three Dimensional ◽  
Real Space ◽  
Two Dimensional ◽  
Efficient Manner ◽  
Fourier Methods ◽  
Tilt Series ◽  
Methods Of Reconstruction

Increased specimen penetration; the principle advantage of high voltage microscopy, is accompanied by an increased need to utilize information on three dimensional specimen structure available in the form of two dimensional projections (i.e. micrographs). We are engaged in a program to develop methods which allow the maximum use of information contained in a through tilt series of micrographs to determine three dimensional speciman structure.In general, we are dealing with structures lacking in symmetry and with projections available from only a limited span of angles (±60°). For these reasons, we must make maximum use of any prior information available about the specimen. To do this in the most efficient manner, we have concentrated on iterative, real space methods rather than Fourier methods of reconstruction. The particular iterative algorithm we have developed is given in detail in ref. 3. A block diagram of the complete reconstruction system is shown in fig. 1.

Computer Assisted Image Reconstruction of Oligomer Structure

1976 ◽  
Vol 34 ◽  
pp. 472-473
Author(s):  
A.M. Jones ◽  
A. Max Fiskin
Keyword(s):  
Three Dimensional ◽  
Depth Of Field ◽  
Computer Assisted ◽  
Projection Data ◽  
Two Dimensional ◽  
Single Particles ◽  
Dimensional Reconstruction ◽  
Computer Assisted Image ◽  
The Fourier Transform ◽  
Space Approach

If the tilt of a specimen can be varied either by the strategy of observing identical particles orientated randomly or by use of a eucentric goniometer stage, three dimensional reconstruction procedures are available (l). If the specimens, such as small protein aggregates, lack periodicity, direct space methods compete favorably in ease of implementation with reconstruction by the Fourier (transform) space approach (2). Regardless of method, reconstruction is possible because useful specimen thicknesses are always much less than the depth of field in an electron microscope. Thus electron images record the amount of stain in columns of the object normal to the recording plates. For single particles, practical considerations dictate that the specimen be tilted precisely about a single axis. In so doing a reconstructed image is achieved serially from two-dimensional sections which in turn are generated by a series of back-to-front lines of projection data.

Sign in / Sign up

Export Citation Format

Share Document