CA1196082A - Displaying seismic sections in isometric view - Google Patents

Displaying seismic sections in isometric view

Info

Publication number
CA1196082A
CA1196082A CA000285029A CA285029A CA1196082A CA 1196082 A CA1196082 A CA 1196082A CA 000285029 A CA000285029 A CA 000285029A CA 285029 A CA285029 A CA 285029A CA 1196082 A CA1196082 A CA 1196082A
Authority
CA
Canada
Prior art keywords
traces
step
display
method
seismic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA000285029A
Other languages
French (fr)
Inventor
Lloyd R. Chapman
Ronan F. O'doherty
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Seiscom Delta Inc
Original Assignee
Seiscom Delta Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Seiscom Delta Inc filed Critical Seiscom Delta Inc
Priority to CA000285029A priority Critical patent/CA1196082A/en
Application granted granted Critical
Publication of CA1196082A publication Critical patent/CA1196082A/en
Application status is Expired legal-status Critical

Links

Abstract

DISPLAYING SEISMIC SECTIONS IN ISOMETRIC VIEW

ABSTRACT OF THE DISCLOSURE

The present invention provides a new and improved method of displaying a plurality of seismic sections of geophysical data on a two-dimensional surface in an iso-metric view, while the display so formed is a display of increased information content.

I.

Description

AsK:kh BACKGROUND OF INVENTION

1. FIELD OF INVENTION:
This invention relates to a method of displaying geophysical data and to a display of such dat~a thus produced.
The invention ls particularly though not e~clusively con~
cerned wlth the display of data ob-tained by seismic methods.
)ESCRIPTION OF PRIOR ART:
In investigating an area of the subsurface of -the earth seismically a series of seismic readings or traces are taken along intersecting lines which define a grid. Typi-cally this will be a rectangular grid though it need not beO
Each such -trace indicates the way in which the subsurface of the earth a-t the point at which it was taken varies wi-th depth. The problem then arises of displaying the -traces in such a way as to produce a display which is meaningful to the eye and from which, therefore, features of par-ticular interest can be picked out.-SU~M~RY OF INVENTION
It is an object of the inven-tion to provide a display of seismic traces and a method of ob-taining i-t.
According to the invention there is provided a geophysical da-ta display representing physical data concerning a portion of the subsurface of the earth which comprises a plurality of sec-tions displayed on a two-dimensional surface in an isome-tric view. ~s used in describing the presen-t inven-tion "isometric" ls intended to mean the representation of an objecL on a single plane with the objec-t placed as in an isomet~ic pro~ection, disregarding any foreshortening ef-Eect. It could alternatively be regarded as a perspective view ;n which the rela-tive lengths and directions of lines .,~

forming the object are as they would be if the view were taken at an infinite distance from the ohject.
The invention also provides a method of displaying geophyslcal data in which the data is in the Eorm of a plur-ality of sectlons forming a grid and each section is composed of a plurality of traces running transversely to the length of the section, wherein the coordinates of the beginnlng and end of each trace are computed in such a way that in any sec-tion each trace is offset parallel to its length by a selected amount with respect to the adjacent traces, the said amount being determined in dependence o~ the view de-sired. All the traces labelled with the computed coordinates are fed to storage. ~11 the stored traces which lie along the same straight line parallel to their length are read out to form a composite trace in which parts of the trace re-place one another if in the desired view they would cover one another. The read out is performed successively for each said straigh-t line, and all the composite traces are fed -to a two-dimensional display means where they are dis played as an isometric view.
BRIEF DESCRIPTION OF DRAWINGS
Fi~. 1 is a seismic or geophysical display ac-cording -to the present invention; and Figs. 2A, 2B and 2C are portions of a flow chart schematically representing the processing technique of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENT
____ .
An example of a method according to the invention wi.ll now be described in the preferred embodiment wi-th ref-erence to the accompanying flow chart (Figs. 2A, 2B and 2C) which sets out schematically the steps involved in con-structing a display using an electronic computer.
The seismic traces to be displayed have been taken during a seismic survey, along grid llnes over an area to be surveyed. The grid lines are defined by some suitable means prior to the survey on the surface of the earthO As will be set forth below, the process of the present inven-tion per-mits a seismic display D of increased information content which permits enhanced analysis of the seismic sections, such as lateral continuity of events between sections.
The first step of the process, indicated schemati-cally at 8 is to establish the positional relationship of the ~rid lines of the survey in terms of the length of those lines and the points at which they intersect. The relation-ship of the lines is obtained from the seismic survey field data. The length of the lines is also obtained from the field data, and these lengths are preferably reduced to a suitable scale according to the size of display D to be formed. In order that the display which is produced shall be isométric in accordance with the present invention, simu- -lating in two dimensions a three dimensional view, it is necessary that the directions represented by the grid lines on the display D not be at right angles to the traces of those grid lines. This point may be more clearly seen by reerring to the display D (Fig. 1) according to the inven-tion. ~xtending upwardly :Erom a plurality of grid lines Lind.icated are a large number of traces (two of which are in-dicated as 10 and 12 t respectively) which when assembled in a side-hy-side relation together produce a seismic sec-tion along each grid line L.

Each such grid line L is at an angle to an x or horizontal axis 14 while the traces are parallel to a y or vertical axis 16. Thus the lower end of each trace in a particular yrid line L is offset from each of its two adja-cent traces along the vertical axis by an amount, known as the gradient or y offset constant, which is the same which-ever trace one is considering in the display D~ A step 18 is -the second step in the method of the invention and is per-formed to determine the amount of this offset required to produce the isometric view which is desired. The amount of this oEfset is determined by the sine of -the angle between the grid lines L and the x axis 14. Provision is made, as indicated in step 20, for the angle between the x axis and the grid line (and hence the offset), to be altered if it is indicated by a decision step 22 to be desired to change the angle of view.
It is often the case that one is not interested in all the geological strata underlying the surface of the earth but only a certain portion thereof. For example, an analyst may only be concerned with the older, lower strata.
If the display ~ included all the stra-ta, the upper strata would at least partly obscure the lower strata, par-ticularly in those areas where the grid lines L intersect o-ther grid lines. Provision is -therefore made according -to the present invention Eor disregarding -those trace portions which are above a particular top "horizon" of interes-t, which is not necessarily a straight line and not necessarily a hor:izontal line. E'or example, a particular reflec-tion even-t of interest may be chosen as the top horizon, as indi-cated by the undulating upper portions of each of the seismic t ~

n~

sections in the display D. This is done in the next step 24 of the method, the said particular line being defined by a succession of selected pointsO If it were deslred ins~ead -to have a lower horizon, a cu-toff view from below, it would be necessary to define a bo-ttom "horlzon" instead of a top one, removing portions of the seismic section therebelow.
A succession of s-teps is next carried out to com-pute the x, y co-ordinates for -the beginning and ends of all the traces of all the sections being displayed. For this 3~
purpose a line of origin, for example a grid line~~ is chosen as indicated by step 28 and all the other grid lines are defined in step 30 using conventional analytic geometry in terms of their length and their ntersections with one another and with the original line~ If necessary, a trans-form may then be applied during step 32 to the whole set of grid line co~ordinates to shiEt the point of origin so that all co-ordinates are positive in order to avoid negative co-ordinates. Conventionally, seismic survey data or traces along a grid line are processed in the sequence in which they are obtained, with a header code defining the par-ticular trace number being incremented by +l between each processing step. Often, particularly during a marine seismic survey, the survey proceeds in alternate direc-tions on alternate grid lines. For example, the survey vessel may move in a direction indicated by an arrow 3~ al.ong a first grid line 36 and in the opposite direction as indicated by an arrow 38 aloncJ a grid line ~0 adjacent the grid line 36.

To permit more orderly processing and facilitate 3o forming -the display of the present inventlon, it is prefer-able to call the traces from memory for display in the order ., .

they occur along the x axis on the display D, necessitatingthat traces in certain of the sections, such as -the section on grid line 40, be called forth in a reverse sequence from their normal processing. To implement this, a decision step 42 determines whether or not a reversal of the line is to take place. If reversal is determined to be required, a step 44 adjusts the header index or increment from ~1 to be -1.

In this manner the last or leftmost trace in a line to be reversed is called forth first, and the header code decre-mented by 1 between each adjacent trace in the reversed line.
Thus, the traces to be displayed are called forth in the order they occur along the x axis even when the survey was obtained in a reversed sequence.
The data contents of the individual traces in the sections are then read along the vertical or y axis during a step 46 and any data above the desired top "horizon" is re-moved during a step 48. The x, y co-ordinates for both ends of each trace are now calculated during a step 50. This can readily be done since the co-ordinates of the grid lines have been defined and each trace occupies a known position along a grid line and is of a known length.
It may be desirable to include in the display D a representation of an auxiliary seismic variable, such as -the reElection strength of the seismic traces. This can advan-tageously be done by using a colored display with different colors representing different reflection strengths, or a multi~variable t,eiSmJ.c display with different display inten-sities of the variable area or variable density display rep-resenting different reflection strengths. Further details of this can be obtained from copending Canadian patent application ~9~

Serial No. 155,0~3 and Canadian Patent No. 1,007,351 assigned to the assignee of the present invention.
An appropriate place for incorporating this feature is shown in the flow chart at a decision step 52 and com-puting step 54 before the trace data is written to mass storage during a step 56.
The trace currently being processed is then stored in mass storage with its accompanying header code during the step 56. A decision step 58 determines if processing of each trace by steps 46, 48 and 50 (as well as 54, where appli-cable) has been performed. If not, control is returned to the step 46 for calling forth another trace for subsequent processing. In this manner, the traces to be disposed are processed and labelled with their x, y co-ordinates in ac-companying header codes and are then fed to mass storage.
The end co-ordinates of the stored traces are then called from storage and sorted into ascending x order, and into ascending y order for each x co-ordinate, so that all traces with common x co-ordinates are sorted into y order, during a sorting processing step 60.
The stage has now been reached when the display D
can be constructed. All traces having a common x co-ordinate are retrieved from mass storage during a step 62 and a com-posite record formed, in a manner set forth below, for that x co-ordinate, The way this is done may be illustrated by considering a vertical line 100 in the display D (Fig. 1).
The trace having the greatest y co-ordinate, and thus nearest a top portion lOOa of the line 100 is the first to be re-trieved durinct a step 62. The trace is then stored during a step 64. A decision step 66 determines whether all traces for -the currently processed x co-ordinate have been called.
If not, the next trace down or having the next largest y co-ordinate is then retrieved. For those y co-^ordinates of the new trace which are the same co-ordinates of the previous trace, and thus when displayed overlap or are superimposed over a preceding trace, the data content of the portions of the preceding trace are deleted. For example, those portions of the trace wh.ich begins at lOOa whose y co-ordinates are the same as y co-ordinates of the trace beginning at point lOOb are deleted, since they are not visible in the final display D. Thus, where the upper end of the present trace covers the lower portion of the trace retrieved first, the lower portion of the first trace is deleted.
The process of the present invention continues in the foregoing manner for each -trace wi-th the present x co-ordinate. In the case of the line 100 it involves retrieving five -traces, until there is formed a complete composite re-cord of how the traces along the line 100 appear when viewed20 from the selected view point. At this point, a decision step 66 determines that all traces for the present x co-ordinate .
have been processed, and then composite record so formed is transferred during step 68 to an appropriate output display device. A decision step 70 determines whether all x co-ordinates have been processed by steps 62, 64 and 68. If not, the present x co-ordinate header is incremented by one, and control returned to step 62 for further processing in the above manner. The foregoing procedure is carried out for all x co-ordinates to build a composi.te record which can then be di.splayed on a suitable fla-t or two-dimensional surface, e.g. photographically or by o-ther means, and will appear in 3~

a Eorm like that shown in the display D (Fig. 1).
It should be understood that the foregoing embodi-ment is the preEerred embodiment of the present invention, although- numerous modifications, adjustments, changes in the program language or flow chart format, or the data output format, all coming within the scope of the appended claims, will occur to those of ordinary skill in the art.

Claims (9)

CLAIMS:
1. A method of forming on a two-dimensional display surface an isometric seismic display to simulate a three-dimension view of seismic traces in plural seismic sections, obtained along a two-dimensional grid of survey lines comprising the steps of:
(a) assigning a two-dimensional, positional rela-tionship on the display surface to the survey grid lines in terms of their respective lengths and intersection points on the display surface according to the isometric view to be formed;
(b) assembling the seismic traces in an order with respect to each other in accordance with the positional relationship assigned to their grid lines by computing horizontal and vertical co-ordinates for the beginning and ending of the seismic traces; and (c) displaying the assembled seismic traces on the display surface wherein an isometric display is formed of the seismic traces with increased information content on the two-dimensional display surface.
2. The method of Claim 1, wherein said step of assigning comprises the step of:
establishing a gradient for each grid line as defined by the isometric view of the display to be formed.
3. The method Claim 1, wherein said step of assign-ing includes the step of:
transforming the angle of the isometric view to a new angle of view.
4. The method of Claim 1, wherein an origin point is assigned in the survey grid lines and wherein said step of assigning comprises the step of:
establishing horizontal and vertical co-ordinates on a two-dimensional surface for the survey grid lines.
5. The method of Claim 1, including the step of:
storing the traces and their computed horizontal and vertical co-ordinates.
6. The method of Claim 1, including the step of:
arranging the traces in a sequence according to their computed co ordinates.
7. The method of Claim 1, including the step of:
removing data portions of the traces outside horizons of interest.
8. The method of Claim 1, wherein the traces along at least one of the grid lines are obtained in an order oppo-site to the order they would appear on the display and wherein said step of assembling includes the step of:
assembling the traces along such at least one of the grid lines in a reverse order to that in which the traces were obtained.
9. The method of Claim 1, wherein said step of displaying includes the steps of:
(a) retrieving those traces having a common horizontal co-ordinate in their assembled positional rela-tionship in a sequence determined by their vertical co-ordinate in their assembled positional relationship; and (b) removing those portions of the retrieved traces which are overlapped by succeeding retrieved traces.
CA000285029A 1977-08-19 1977-08-19 Displaying seismic sections in isometric view Expired CA1196082A (en)

Priority Applications (1)

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Application Number Priority Date Filing Date Title
CA000285029A CA1196082A (en) 1977-08-19 1977-08-19 Displaying seismic sections in isometric view

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Cited By (25)

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US7552459B2 (en) 1996-05-03 2009-06-23 Starsight Telecast, Inc. Information system
US7996864B2 (en) 1994-08-31 2011-08-09 Gemstar Development Corporation Method and apparatus for displaying television programs and related text
US8272011B2 (en) 1996-12-19 2012-09-18 Index Systems, Inc. Method and system for displaying advertisements between schedule listings
US8336071B2 (en) 1996-12-19 2012-12-18 Gemstar Development Corporation System and method for modifying advertisement responsive to EPG information
US8359616B2 (en) 2009-09-30 2013-01-22 United Video Properties, Inc. Systems and methods for automatically generating advertisements using a media guidance application
US8453174B2 (en) 1995-10-02 2013-05-28 Starsight Telecast, Inc. Method and system for displaying advertising, video, and program schedule listing
US8613020B2 (en) 1998-04-30 2013-12-17 United Video Properties, Inc. Program guide system with flip and browse advertisements
US8612310B2 (en) 2005-12-29 2013-12-17 United Video Properties, Inc. Method and system for commerce in media program related merchandise
US8793738B2 (en) 1994-05-04 2014-07-29 Starsight Telecast Incorporated Television system with downloadable features
US8799954B1 (en) 2006-07-31 2014-08-05 Rovi Guides, Inc. Systems and methods for providing custom media content flipping
US8806536B2 (en) 1998-03-04 2014-08-12 United Video Properties, Inc. Program guide system with preference profiles
US8832742B2 (en) 2006-10-06 2014-09-09 United Video Properties, Inc. Systems and methods for acquiring, categorizing and delivering media in interactive media guidance applications
US8850477B2 (en) 1995-10-02 2014-09-30 Starsight Telecast, Inc. Systems and methods for linking television viewers with advertisers and broadcasters
US8904441B2 (en) 2003-11-06 2014-12-02 United Video Properties, Inc. Systems and methods for providing program suggestions in an interactive television program guide
US8918807B2 (en) 1997-07-21 2014-12-23 Gemstar Development Corporation System and method for modifying advertisement responsive to EPG information
US9015750B2 (en) 1998-05-15 2015-04-21 Rovi Guides, Inc. Interactive television program guide system for determining user values for demographic categories
US9021538B2 (en) 1998-07-14 2015-04-28 Rovi Guides, Inc. Client-server based interactive guide with server recording
US9319735B2 (en) 1995-06-07 2016-04-19 Rovi Guides, Inc. Electronic television program guide schedule system and method with data feed access
US9426509B2 (en) 1998-08-21 2016-08-23 Rovi Guides, Inc. Client-server electronic program guide
US9591251B2 (en) 1997-10-06 2017-03-07 Rovi Guides, Inc. Interactive television program guide system with operator showcase
US9736524B2 (en) 2011-01-06 2017-08-15 Veveo, Inc. Methods of and systems for content search based on environment sampling
US9749693B2 (en) 2006-03-24 2017-08-29 Rovi Guides, Inc. Interactive media guidance application with intelligent navigation and display features
US9848276B2 (en) 2013-03-11 2017-12-19 Rovi Guides, Inc. Systems and methods for auto-configuring a user equipment device with content consumption material
US10015562B2 (en) 2000-03-31 2018-07-03 Rovi Guides, Inc. System and method for metadata-linked advertisements
US10063934B2 (en) 2008-11-25 2018-08-28 Rovi Technologies Corporation Reducing unicast session duration with restart TV

Cited By (41)

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US8793738B2 (en) 1994-05-04 2014-07-29 Starsight Telecast Incorporated Television system with downloadable features
US7996864B2 (en) 1994-08-31 2011-08-09 Gemstar Development Corporation Method and apparatus for displaying television programs and related text
US9319735B2 (en) 1995-06-07 2016-04-19 Rovi Guides, Inc. Electronic television program guide schedule system and method with data feed access
US8453174B2 (en) 1995-10-02 2013-05-28 Starsight Telecast, Inc. Method and system for displaying advertising, video, and program schedule listing
US8850477B2 (en) 1995-10-02 2014-09-30 Starsight Telecast, Inc. Systems and methods for linking television viewers with advertisers and broadcasters
US8776125B2 (en) 1996-05-03 2014-07-08 Starsight Telecast Inc. Method and system for displaying advertisements in an electronic program guide
US7552459B2 (en) 1996-05-03 2009-06-23 Starsight Telecast, Inc. Information system
US9423936B2 (en) 1996-05-03 2016-08-23 Rovi Guides, Inc. Information system
US8646005B2 (en) 1996-05-03 2014-02-04 Starsight Telecast, Inc. Information system
US8806538B2 (en) 1996-05-03 2014-08-12 Starsight Telecast, Inc. Information system
US9027058B2 (en) 1996-05-03 2015-05-05 Rovi Guides, Inc. Information system
US8448209B2 (en) 1996-12-19 2013-05-21 Gemstar Development Corporation System and method for displaying advertisements responsive to EPG information
US8726311B2 (en) 1996-12-19 2014-05-13 Gemstar Development Corporation System and method for modifying advertisement responsive to EPG information
US8635649B2 (en) 1996-12-19 2014-01-21 Gemstar Development Corporation System and method for modifying advertisement responsive to EPG information
US8336071B2 (en) 1996-12-19 2012-12-18 Gemstar Development Corporation System and method for modifying advertisement responsive to EPG information
US8272011B2 (en) 1996-12-19 2012-09-18 Index Systems, Inc. Method and system for displaying advertisements between schedule listings
US8732757B2 (en) 1996-12-19 2014-05-20 Gemstar Development Corporation System and method for targeted advertisement display responsive to user characteristics
US9015749B2 (en) 1997-07-21 2015-04-21 Rovi Guides, Inc. System and method for modifying advertisement responsive to EPG information
US9191722B2 (en) 1997-07-21 2015-11-17 Rovi Guides, Inc. System and method for modifying advertisement responsive to EPG information
US8918807B2 (en) 1997-07-21 2014-12-23 Gemstar Development Corporation System and method for modifying advertisement responsive to EPG information
US9591251B2 (en) 1997-10-06 2017-03-07 Rovi Guides, Inc. Interactive television program guide system with operator showcase
US8806536B2 (en) 1998-03-04 2014-08-12 United Video Properties, Inc. Program guide system with preference profiles
US8613020B2 (en) 1998-04-30 2013-12-17 United Video Properties, Inc. Program guide system with flip and browse advertisements
US9635406B2 (en) 1998-05-15 2017-04-25 Rovi Guides, Inc. Interactive television program guide system for determining user values for demographic categories
US9015750B2 (en) 1998-05-15 2015-04-21 Rovi Guides, Inc. Interactive television program guide system for determining user values for demographic categories
US9226006B2 (en) 1998-07-14 2015-12-29 Rovi Guides, Inc. Client-server based interactive guide with server recording
US9021538B2 (en) 1998-07-14 2015-04-28 Rovi Guides, Inc. Client-server based interactive guide with server recording
US9232254B2 (en) 1998-07-14 2016-01-05 Rovi Guides, Inc. Client-server based interactive television guide with server recording
US10075746B2 (en) 1998-07-14 2018-09-11 Rovi Guides, Inc. Client-server based interactive television guide with server recording
US9426509B2 (en) 1998-08-21 2016-08-23 Rovi Guides, Inc. Client-server electronic program guide
US10015562B2 (en) 2000-03-31 2018-07-03 Rovi Guides, Inc. System and method for metadata-linked advertisements
US8904441B2 (en) 2003-11-06 2014-12-02 United Video Properties, Inc. Systems and methods for providing program suggestions in an interactive television program guide
US8612310B2 (en) 2005-12-29 2013-12-17 United Video Properties, Inc. Method and system for commerce in media program related merchandise
US9749693B2 (en) 2006-03-24 2017-08-29 Rovi Guides, Inc. Interactive media guidance application with intelligent navigation and display features
US8799954B1 (en) 2006-07-31 2014-08-05 Rovi Guides, Inc. Systems and methods for providing custom media content flipping
US9215504B2 (en) 2006-10-06 2015-12-15 Rovi Guides, Inc. Systems and methods for acquiring, categorizing and delivering media in interactive media guidance applications
US8832742B2 (en) 2006-10-06 2014-09-09 United Video Properties, Inc. Systems and methods for acquiring, categorizing and delivering media in interactive media guidance applications
US10063934B2 (en) 2008-11-25 2018-08-28 Rovi Technologies Corporation Reducing unicast session duration with restart TV
US8359616B2 (en) 2009-09-30 2013-01-22 United Video Properties, Inc. Systems and methods for automatically generating advertisements using a media guidance application
US9736524B2 (en) 2011-01-06 2017-08-15 Veveo, Inc. Methods of and systems for content search based on environment sampling
US9848276B2 (en) 2013-03-11 2017-12-19 Rovi Guides, Inc. Systems and methods for auto-configuring a user equipment device with content consumption material

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