Manual Sei See Doc

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SeiSee (2.22)

User’s Manual[1]

Introduction

SeiSee program shows seismic data in SEG-Y, CWP/SU, CGG CST formats on screen of your personal computer (Windows-2000, XP, Vista Windows-7, 8, Linux+Wine).

Program features:

 standard integer (2,4 bytes) and IBM float (4 bytes) sample formats support

 nonstandard integer(1 byte), float IEEE (4 bytes) sample formats[2]

 CGG Geovecteur disk SEG-Y format (.dat)

 various seismic display modes (wiggle, variable area, variable density, color)

 import-export color palettes to text file

 scaling seismic image, gain control, axes labeling setup

 plot seismic to printer (plotter)

 image export in Windows Bitmap (.bmp) and PostScript formats.

 SEG-Y trace headers display (formats Integer*1,*2,*4, IEEE Float*4,*8, IBM Float*4 are supported)

 search trace by header item value

 data samples browsing

 text header and binary editor

 band pass filter, automatic gain control (AGC)

 headers consistency check

 write whole SEG-Y file or part of it to disk in SEG-Y (IBM-32/IEEE) or CWP/SU format with ability to select data on base of trace index or trace header value or trace header expression and given time interval; reversal trace order is also supported. Processing parameters can be applied to recorded data (filter, AGC etc).

 export trace(s) sample and header values to text file

 import trace headers values from text file

 trace shift according with “Delay Recording Time” trace header value

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 selection of traces to be displayed by trace index or header value and by expression

 trace headers change by means expressions

 trace sorting

 open and fix files containing wrong data in binary header (Recovery Mode)

 single trace header item editing

 disc directory browsing

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Starting the program

Double click program icon by mouse: Main window will be shown

Use button to toggle controls panel visibility, and for directory browser.

Command line startup mode is also supported. Use first parameter to specify a SEG-Y file name.

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

Using the program

Open SEG-Y (SU) or CST file

Select menu “File”  “Open”, or press button: .

Standard “Open” dialog appears. Use it for to select file that you want to browse

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Open Directory Browser panel

Select “File”  “Open Directory” menu. Standard “Open” dialog appears. Use it for directory selection, then select any file in it and press “Open” button.

The Browser panel will be shown:

(Only “valid” SEG-Y, CWP/SU and CST files will be listed)

To display SEG-Y file just select it in the list by mouse. The panel buttons:

- Return to the previous directory - Refresh directory list

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Open file in Recovery mode (SEG-Y only)

If file has wrong values in “Sample Interval”, “Number samples per data trace for reel” или “Data Sample Code” items of the binary header, the program opens file in Recovery Mode. Only text and binary header will be read. It is necessary to fix the values and reopen the file again.

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Selection of traces to be displayed

To change the parameters choose “File”  “Trace Selection” menu, or press button.

Trace selection by trace number or header item value

Choose “By Number” tab, then fill in selection parameters form and press “Select” button, after this the program will start trace selection. When it is done, press “OK” button to display selected data or “Cancel button” to discard the selection.

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Trace selection by expression

Select “By Expression” tab, then enter expression text, and press “Select” button, after this the program will start trace selection. Expression syntax is described in the “Expressions” appendix. When it is done, press “OK” button to display selected data or “Cancel button” to discard the selection.

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Trace Sorting

To setup sorting select menu “File”  “Trace Sort”, or press button.

The dialog has two lists. “Selected Headers” list contains trace header item names that will be used for sorting, and “Available Headers” list holds all trace headers.

Header order in the “Selected Headers” list corresponds precedence of using them in sorting.

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Назначения элементов управления здесь следующее:

Control Description

Add selected header item from "Available Headers" to "Selected Headers" list

Remove selected header item from "Selected Headers" list Clear "Selected Headers" list

Move selected header item in "Selected Headers" Up Move selected header item in "Selected Headers" Down

To select sort mode check suitable item in “Sort Mode” panel

Control Description No No sorting

Ascending Ascending sorting Descending Descending sorting

To apply selected mode, press “Sort” button, and then press “OK” When sorting is active the “Sort” mark is shown in status bar:

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Saving data to SEG-Y or CWP/SU file

To save file select “File”  “Save As ” menu item or press button. It is possible to save all trace or part of them. Fill selection parameters in the dialog. Selection parameters are the same as described in “Selection of traces to be displayed” chapter.

Check “Reversal order” checkbox to save traces in reversal order. Check “Apply Processing” to save data with processing applied.

Then press “Save” button. When standard “File Save” dialog appears, use it to specify output file. “Close” button discards dialog.

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Then press “Save” button. When standard “File Save” dialog appears, use it to specify type and name of output file. “Close” button discards dialog.

The following data formats are supported  SEG-Y – IBM-FLOAT-32 samples  SEG-Y – IEEE-FLOAT-32 samples  CWP/SU

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Save trace(s) sample and header values to text file Procedure is same as for Saving SEG-Y file, except you need to set “Трасе Samples Text File” file type.

To save trace header values together with trace data check “Include Headers (txt)” checkbox.

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Export trace headers values to the text file To export select the following menu items:

“File”  “Export Trace Headers to ASCII file”

Check “Write Column info” if column information is needed.

Press “Save” to start export. Header values that are selected in the “Trace Headers” window will be exported to output file.

Here is structure of the output file: P 0 F 0 Trace index in file

P 9 F 4 * FFID - Original field record number P 17 F 4 SP - Energy source point number P 21 F 4 CDP ensemble number P237 F14 New Item 1 EXPR SP from CDP = 1 858 1100 1519 0.25 860 2 858 1100 1520 0.5 860.5 3 858 1100 1521 0.75 861 4 858 1100 1522 1 861.5 5 858 1100 1523 1.25 862 6 858 1100 1524 1.5 862.5

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At the beginning of the file column information will be recorded (if “Write Column Info” is checked):

Position Contents Description 1 - 4 Pnnn

or EXPR

nnn – number that shows byte position of header item if value is expression

5 space

6 - 8 Fnn or three spaces

nn – number for the appropriate format if value is expression

9 space

10 - text header item description

The next line is column info terminator – line that starts with “+” character. Header item values will be placed after this line

First column contains ordinal number of the trace (as it is in file, starting from 1). The following columns contain header values.

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Import trace header values from text file

File to be imported should be in the same format as exported file. To import header values from file select the following menu: “File”  “Import Trace Headers from ASCII file”

Press “Load” to start import.

Select input file and press “Open”

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Sometimes time of first trace sample is defined by “Delay Recording Time” trace header value. It is necessary to switch-on “Apply Recording Delay Header” to display seismic line with such traces properly. While working in this mode you can note some file opening delay, especially if file size if big. If you are sure that traces in current file are not shifted than you can toggle this mode off.

To toggle the mode select “File”  “Apply Recording Delay Header” menu

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Display mode selection.

“Display mode” and “Wiggle Fill” panels

The modes and corresponding controls’ positions are shown in the following table

Mode Controls position Seismic sample

1 Wiggle

2 Wiggle + Positive Fill (Variable area)

3 Wiggle + Negative Fill

4 Variable density (Gray levels)

5 Color

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Display Mode panel controls Description

Wiggle Wiggle mode

Gray Variable density mode

Color Color mode

Wiggle Fill panel controls Description

None No wiggle fill Positive Positive fill Negative Negative fill

“Colors” panel

Use this panel to select colors:

Colors panel controls Description

Wiggle Wiggle color

Fill Fill color

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Color mode palette setup

Press button to popup “Palette” dialog.

The following buttons use to control the palette list:

Button Description

Create new palette Duplicate current palette Remove current palette Check all palettes for export Uncheck all

Export selected palettes to file Import palettes from file

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When palette is selected in the list, it is applied to the seismic window. Before editing select needed palette in the list.

The palette consists of color markers; space between two markers is filled by linear interpolation of color.

Originally the palette is made of three markers:

# Marker Description

1 -100% Maximal negative amplitude value 2 0% Zero amplitude level

3 +100% Maximal positive amplitude value

To select a marker pick it by mouse in the “Markers/Levels” panel.

To choose new color for a marker, use panel of colors in the right part of the dialog. Selected color will be shown “Selected Color” field. To assign the color to the selected marker, press “Assign Color” button.

To add a new marker, press “Add Marker” button. New marker will be added between selected and previous markers.

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To remove selected marker, press “Delete Marker” button.

Marker position can be changed by moving marker position control by mouse.

To save current changes, press “Update” button, and to cancel the changes press “Reset”.

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Scaling and gain setup Scale panel

Scale panel controls Description

Traces Set trace number per centimeter

Fit seismic section to window horizontally Time Set time scale (cm/sec)

Fit seismic section to window vertically Gain-w Wiggle Gain control

Automatically adjust current wiggle gain, using maximal amplitude values of selected trace (see “Trace Selection article”)

Gain-с Color Gain control

Automatically adjust color mode gain

= Check this if you need same gain value for both modes

To adjust a value by mouse, move mouse cursor to the corresponding slider ( ), then press left mouse button, and (keeping it pressed) move the slider. Current value of the parameter will be shown in edit control that is on the right of the slider, and seismic image will be repainted to reflect the changes.

Direction panel

Direction panel control Description

Normal From left to right Reversed From right to left

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Change scale and gain by mouse wheel

Mouse Position during Wheel

rotating Action

In the Traces input filed,

In the Time Axis Change horizontal scale In the Time input field,

In the Headers Axis Change vertical scale

In the Seismic Section window Zoom-In/Zoom-out in both directions It the Gain-w input field Change Wiggle mode gain

In the Gain-с input field Change Color mode gain

Direction panel

.

Control Description

Normal From left to right Reversed From right to left

Zoom buttons.

Fit all the image to seismic window size

Zoom by window. Press this button then draw a rectangle on the seismic window (move mouse cursor to first corner of the rectangle, press left mouse button, and keeping it pressed, move mouse to set desired size). Selected region will be zoomed to size of the seismic window.

Return to previous zoom Zoom in (1.5 times) Zoom out (1.5 times)

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Direction of scale changing caused by , , buttons depends on the following radio-buttons selection:

Scale changes in both directions Scale changes in horizontal direction Scale changes in vertical direction

Default Seismic View Parameters

Select menu “View”  “Set Seismic View Defaults” to set defaults for seismic section

Select “View”  “Set Velocity View Defaults” to set defaults for velocity section (in SEG-Y format)

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Seismic window

To show this window select “Seismic” tab.

When you move mouse pointer in the seismic window, values corresponding current position will be shown in status bar at the bottom of the main window and in “Mouse Position Header Box”

Trc Trace number in the file Time Time (ms)

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Axes labeling setup

Press button, to popup Axes dialog.

The dialog has two tabs. To select headers that should be shown on the top of seismic, click “Trace Axis (Headers)” tab.

There are two lists on this tab: "Selected Headers" list contains descriptions of trace header items that will be shown above seismic section, and "Available Headers" list contains all the SEG-Y trace header items.

Item order in "Selected Headers" corresponds to its position on axis (higher or lower)

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Controls on "Trace Axis" tab:

Control Description

Add selected header item from "Available Headers" to "Selected Headers" list

Remove selected header item from "Selected Headers" list Clear "Selected Headers" list

Move selected header item in "Selected Headers" Up Move selected header item in "Selected Headers" Down

For each item in "Selected Headers" you can specify start value and step. For example: Select "CDP ensemble number” item, assign start value=10 and step=10 to it. In this case traces with CDP numbers = 10, 110, 210, etc will be labeled.

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To setup time axis labeling step click “Time Axis” tab.

Enter the step value. If time lines are needed set mark in the “Timelines” checkbox.

To accept the changes press “Apply” or “OK” button. “OK” also closes the dialog. “Close” button discards any changes and closes the dialog.

Scrolling the seismic image

There are two ways to scroll the image:

 using scroll bars

 dragging by mouse

Move mouse cursor to start point, then press RIGHT mouse button and keeping it pressed, move the image into desired direction.

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Trace selection

To switch into selection mode press button. It is the same button that is used to switch into “Pan” mode. Image on button, depict mode that will be selected after the button press.

While selection mode is chosen, move mouse cursor to desired trace and press left mouse button. As result, this trace becomes “selected”.

Trace header values of the selected trace will be shown in “Bin header” panel (see “Display headers” article).

This trace is also used for automatic gain control.

To move trace selection some number traces forward or backward use the following controls:

Fill edit control with move step value

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Display, edit headers and data

After button is pressed, “Info/Headers” panel will be shown in the left part of the seismic window:

Contents of the panel depend on which radio-button is checked.

Button Contents

General General file information Trace header Header of the selected trace Bin header Binary header of SEG-Y file Text header Text header of SEG-Y file Trace data Trace data sample values Spectrum Power spectrum graph

To change the panel size, move mouse cursor to the right boundary. And when the mouse cursor is changed into , press left mouse button, and holding it pressed move panel boundary into desired direction.

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Trace header items browsing

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Besides browsing of known header items (“Items” tab), it is also possible to display trace header as dump of integer values array for nonstandard data analysis (“Dump” tab).

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SEG-Y file text header editing[3]

Select “Text Header” tab to show contents of the text header.

Select appropriate line of the header by mouse then enter changes from keyboard.

To save the changes press “Update” button, or press “Reset” button to undo all the changes[4]_.

It is also possible to load text header data from text (ASCII) file. To do this press “From file” button or select menu “File”  “Load Text Header from

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File”. To load the data from the previous file, press small button that is on the right of the “From file” button.

To save the header into text (ASCII) file select “File”  “Save Text Header to File” menu item.

It is also possible to load text header data from text (ASCII) file. To do this press “From file” button or select menu “File”  “Load Text Header from File”. To load the data from the previous file, press small button that is on the right of the “From file” button.

To save the header into text (ASCII) file select “File”  “Save Text Header to File” menu item.

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SEG-Y file binary header editing[5]

Select “Bin Header” tab to show contents of the text header.

Select appropriate line of the header by mouse then enter changes from keyboard. “Sample Interval”, “Number samples per data trace for reel” and “Data Sample Code” items cannot be changed because they affect to file integrity. If you need nevertheless to edit these items, then check “Allow to edit all items” box.

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Program will not update file till all the bad values are corrected.

To save the changes press “Update” button, or press “Reset” button to undo all the changes[6]_.

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Trace Headers window Header Items browsing

To show this window select “Trace Headers” and “View” tabs.

Check items in Selection panel that you want to display. Values of selected header items will be shown in Data panel.

Pressing to button selects all the items, and clears all selection. The program checks for trace headers consistence. If current trace header value difference with previous trace header is not equal difference with next trace, this value is highlighted by red color.

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Custom header items creation

The program allows create custom header item description. Use control panel buttons for this.

The button creates a new header and shows editing dialog window The button shows editing dialog window for current header item

The button removes the current item

Note: you can edit only custom header items. There are two types of items:

 positional: 16 or 32-bit integer, from arbitrary header position

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In case of positional item we have the following dialog:

Fields:

Name Item name: it should be unique, it will be used for header axis labeling in seismic window and for table column labeling in the trace header window

Description Header item description

Position Byte position (from 1) for this item in trace header Format Select needed format from combo box: Integer*1,*2,*4,

IEEE Float*4,*8, IBM Float*4

You can copy position and format from existing item to “Position” и “Format” fields. To do this, select item in “Available Headers” list and press button.

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To create a computable item select “Expression” tab

Enter an expression that consists from numbers, parenthesizes, operators (+-/*) and special variables

Examples:

Expression Description

N - current trace number in the file N*2 - same multiplied by 2

2 - just value 2

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Тrace Searching

Go to end or beginning of the file  - go to the first trace

 - go to the last trace

Go to the trace with given index

To activate this mode click left mouse button over “Trace #” table header

Fill in search number (N)

Select search condition from the list:

 = go to trace index of which is equal of the search number

 + go N traces forward

 - go N trace backward

Trace search by header item value

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(like “CDP”)

Fill in search number (N)

Select search condition from the list:

 = find trace where selected header item value is equal N

 + find trace where selected header item value is equal current value + N

 - find trace where selected header item value is equal current value - N

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Press one of the following buttons:  - sequential search forward

 - sequential search backward



 - fast binary search[7]_{, it works only on ordered sequence of values}

(ascended or descended) (≠ is not supported)

If file size is big, then search may take sufficient amount of time. Press button to terminate current search.

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Trace header editing

Single trace header item modification

Move mouse pointer to table cell with header item value that you are going to change and press left mouse button.

Name and value of selected item will be shown on screen

Fill in edit field by new item value and press Update button

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Trace headers changing by expression

Headers of selected traces (See: “Selection of traces to be displayed” article) can be changed by means mathematical expressions.

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Check header to be changed in the selection panel, then in data panel click table header corresponding to it in the data panel:

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Then fill in “Expression” field with expression text. The following variables have a special meaning:

Variable Description

N Ordinal trace number in SEG-Y file L Last trace number in SEG-Y file

Function that returns arbitrary trace header item value is also defined:

Н(p,f), where p – item position in the header, f – format (2-integer*2, 4-integer*4)

For example: H(21,4) returns CDP number. Toolbar buttons:

Inserts value of item currently selected in the selection panel

Inserts current trace number in the expression

Insert last trace number

Clears expression field

Update file with new values

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Repeat all above for each item you want to change and then press button.

The following dialog will be shown:

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Hardcopy window

To show this window select “Hardcopy” tab.

Печать изображения

To print seismic image select “Print” tab.

Press “Setup” button to choose printer and page size. Standard “Print setup” dialog will be shown. Use it to setup your parameters. Information about selected printer will be shown in “Printer Info” panel.

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It is possible only part of seismic section, for that you need to fill in Print Region form:

Tmin Minimal Time (ms) Tmax Maximal Time (ms) From tr. Start from this trace То tr. Stop at this trace

Use “min” and “max” buttons to set minimal or maximal possible values. Press “All” button to print (export) whole section, and “View” button to print Seismic View image.

To place text label (one string) from “Label” edit control to printout set mark into checkbox. “File name” button puts current file name into edit control, and “Clear” button empties the control.

If image size is bigger then page size then it will be spitted into several parts.

Print preview panel shows as image is divided into pages. If you changed display mode, scaling, etc, then current changes also will be reflected in the preview panel.

To print the image, press “Print” button. The button label changes to “Abort Print”. Printing progress will be shown in progress bar at the bottom of the window..

To cancel printing, press “Abort Print” button.

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Экспорт изображения сейсмики в формате Windows Bitmap (.bmp) Select “Export” tab in “Hardcopy” window

Fill “Bitmap Dpi” field with "dot per inch" value for your bitmap image In “Color Mode” select image type: 256-color (color 8-bit) or black and white (b/w -1 bit).

Then press “Export” button. When standard “File Save” dialog appears, use it to specify output file. “Close” button discards dialog.

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Processing

Processing is applied to trace before it will be shown on screen. Here is the processing modules list:

 band pass filter

 automatic gain control (AGC)

 data inversion (negation) Processing parameters setup

To set the processing parameters press button or select “Processing”  “Parameters” menu item, after that “Processing” dialog appears. Enter parameters needed. To accept the parameters press “Apply” or “OK” button. “OK” also closes the dialog. “Close” button discards any changes and closes the dialog.

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Processing panel

.

Use the panel to toggle corresponding processing.

Processing panel item Description

Inversion Data inversion (Negation) Filter Band pass filter

Agc or Norm Automatic gain control or Normalization Weight Use Trace Weighting Factor trace header item

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Band pass filter

Enter filter cut frequencies as it is shown in the picture and check “Use filter”, if you want to use the filter.

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Automatic gain control (AGC)

In “Use Normalization” mode maximum amplitude value is calculated for trace and each sample is divided to its value.

In “Use AGC” mode “Window length” parameter sets AGC window length. AGC module moves the window down the trace sample-by-sample and calculates a scale factor at each location. The scale factor is equal to the RMS amplitude in the window.

Enter “Window length” and check “Use AGC”, if you want to use the AGC.

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Inversion

This module replaces each sample in trace to inversed value (multiply by minus one).

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Power Spectrum window

To show the Spectrum window press button or select menu: “View”  “Spectrum”.

(amplitude - %, frequency - Hz)

Use the following check boxes to control spectrum charts curves:

Check Box Description

Whole Section Whole section summary spectrum

Range Spectrum of selected region (see Selection table) Current Trace Spectrum of current reace

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To calculate rectangular region spectrum fill “Selection” table from keyboard

When it is done press button.

Press button to fill the table with current seismic section boundaries. Also you can select the region by mouse in seismic window – button

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Appendices

Expressions

Special variables and header item value function The following variables have a special meaning:

Variable Description

N Ordinal trace number in SEG-Y file L Last trace number in SEG-Y file

Function that returns arbitrary trace header item value is also defined:

Н(p,f), where p – item position in the header, f – format (2-integer*2, 4-integer*4)

For example: H(21,4) returns CDP number.

Expression Syntax

Expressions have pretty much the same syntax as they would have on paper, with the following exceptions:

 Each expression must end with a semicolon. This is because the expression string can actually contain multiple expressions. The semicolon is used to mark the end of the expression. In our case semicolon at the end of the expression can be omitted.

Examples: o 4*x+5;

o y=5+2;g=4+6;

o y=r*sin(a);x=r*cos(a);

 The asterisk '*' must be used to multiply.

Examples:

o y=5*6; Valid

o g=(x+1)*(x-1); Valid o g=(x+1)(x-1); Invalid

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More than one expression may be contained within an expression string. As shown above, each expression must end with a semicolon, even if only one expression is in the string. The value of an expression string is the value of the last expression in the string.

Examlples:

 g=7; Value: 7

 k=z+1; Value: z+1

 r=4;k=6;o=9+r-k; Value: 9+r-k

Some functions may take reference parameters. These parameters are

references to other variables. You can mix reference parameters with normal parameters. The order of the normal parameters must remain the same and the order of the reference parameters must remain the same.

Examples:

 min(1,2,3,4,&mval); &mval is a reference to a variable mval

 min(1,2,&mval,3,4); You may mix them inside like this.

 min(1,2,(&mval),3,4); You may not nest reference parameters in any way Expressions may also be nested with parenthesis.

Examples:

 y=sin(x-cos(5+max(4,5,6*x)));

 6+(5-2*(x+y));

Expressions may also have whitespace characters and comments.

Whitespace characters such as newlines, linefeeds, carriage returns, spaces, and tabs are ignored. Comments begin with the less than-sign '<' and end with the greater than-sign '>'. Comments may be nested as well.

Example:

<Set the x value> x = d * cos(r); <Set the y value> y = d * sin(r);

t = x; x = y; y = x;

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If a variable is used in an expression, but that variable does not exist, it is considered zero. If it does exist then its value is used instead.

ExprEval Internal Functions (by Brian A. Vanderburg II) The following functions are provided with ExprEval:

Function Min.Arg s Max . Args Min. Ref Arg s Max . Ref Args Result/Comment

abs(v) 1 1 0 0 Absolute value of v. abs(-4.3) returns 4.3 mod(v,d) 2 2 0 0 Remainder of v/d.

mod(5.2,2.5) return 0.2 ipart(v) 1 1 0 0 The integer part of v._{ipart(3.2) returns 3} fpart(v) 1 1 0 0 The fractional part of v._{fpart(3.2) returns 0.2} min(v,...) 1 Non_e 0 0 The minimum number passed._{min(3,2,-5,-2,7) returns -5} max(v,...) 1 Non_e 0 0 The maximum number passed._{max(3,2,-5,-2,7) returns 7} pow(a,b) 2 2 0 0 The value a raised to the power b.

pow(3.2,1.7) returns 3.21.7

sqrt(a) 1 1 0 0 The square root of a. sqrt(16) returns 4 sin(a) 1 1 0 0 The sine of a radians._{sin(1.5) returns around 0.997}

sinh(a) 1 1 0 0 The hyperbolic sine of a._{sinh(1.5) returns around 2.129} asin(a) 1 1 0 0 The arc-sine of a in radians._{asin(0.5) returns around 0.524} cos(a) 1 1 0 0 The cosine of a radians.

cos(1.5) returns around 0.0707

cosh(a) 1 1 0 0 The hyperbolic cosine of a. cosh(1.5) returns around 2.352

acos(a) 1 1 0 0 The arc-cosine of a in radians._{acos(0.5) returns around 1.047} tan(a) 1 1 0 0 The tangent of a radians._{tan(1.5) returns around 14.101}

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atan(a) 1 1 0 0 The arc-tangent of a in radians._{atan(0.3) returns about 0.291}

atan2(y,x) 2 2 0 0 The arc-tangent of y/x, with quadrant correction._{atan2(4,3) returns about 0.927} log(a) 1 1 0 0 The base 10 logarithm of a._{log(100) returns 2}

pow10(a) 1 1 0 0 10 raised to the power of a. pow10(2) returns 100 ln(a) 1 1 0 0 The base e logarithm of a.

ln(2.8) returns around 1.030 exp(a) 1 1 0 0 e raised to the power of a._{exp(2) returns around 7.389} logn(a,b) 2 2 0 0 The base b logarithm of a._{logn(16,2) returns 4}

ceil(a) 1 1 0 0 Rounds a up to the nearest integer._{ceil(3.2) returns 4} floor(a) 1 1 0 0 Rounds a down to the nearest integer._{floor(3.2) returns 3} rand() 0 0 0 0 Returns a number between 0 up to but not

including 1.

random(a,b) 2 2 0 0 Returns a number between a up to and including b.

srand(a) 1 1 0 0

Seeds the random number generator with a value.

Return value is unknown randomize() 0 0 0 0

Seed the random number generator with a value based on the current time.

Return value is unknown

deg(a) 1 1 0 0 Returns a radians converted to degrees. deg(3.14) returns around 179.909 rad(a) 1 1 0 0 Returns a degrees converted to radians.

rad(180) returns around 3.142 recttopolr(x,y) 2 2 0 0

Returns the polar radius of the rectangular co-ordinates.

recttopolr(2,3) returns around 3.606 recttopola(x,y) 2 2 0 0

Returns the polar angle (0...2PI) in radians of the rectangular co-ordinates.

recttopola(2,3) returns around 0.588 poltorectx(r,a) 2 2 0 0

Returns the x rectangular co-ordinate of the polar co-ordinates.

poltorectx(3,1.5) returns around 0.212 poltorecty(r,a) 2 2 0 0 Returns the y rectangular co-ordinate of the polar co-ordinates.

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if(c,t,f) 3 3 0 0

Evaluates and returns t if c is not 0.0. Else evaluates and returns f.

if(0.1,2.1,3.9) returns 2.1

select(c,n,z[,p]) 3 4 0 0

Returns n if c is less than 0.0. Returns z if c is 0.0. If c is greater than 0.0 and only three arguments were passed, returns z. If c is greater than 0.0 and four arguments were passed, return p.

select(3,1,4,5) returns 5

equal(a,b) 2 2 0 0 Returns 1.0 if a is equal to b. Else returns 0.0_{equal(3,2) returns 0.0} above(a,b) 2 2 0 0 Returns 1.0 if a is above b. Else returns 0.0_{above(3,2) returns 1.0} below(a,b) 2 2 0 0 Returns 1.0 if a is below b. Else returns 0.0_{below(3,2) returns 0.0} avg(a,...) 1 Non_e 0 0 Returns the average of the values passed._{avg(3,3,6) returns 4}

clip(v,min,max) 3 3 0 0

Clips v to the range from min to max. If v is less than min, it returns min. If v is greater than max it returns max. Otherwise it returns v.

clip(3,1,2) returns 2 clamp(v,min,max

) 3 3 0 0

Clamps v to the range from min to max, looping if needed. clamp(8.2,1.3,4.7) returns 1.4 pntchange(side1o ld, side2old, side1new, side2new, oldpnt) 5 5 0 0

This is used to translate points from different scale. It works no matter the orientation as long as the sides are lined up correctly.

pntchange(-1,1,0,480,-0.5) returns 120 (x example) pntchange(-1,1,480,0,-0.5) returns 360 (y example) poly(x,c1,...) 2 Non e 0 0

This function calculates the polynomial. x is the value to use in the polynomial. c1 and on are the coefficients.

poly(4,6,9,3,1,4) returns 2168

same as 6*44_{+ 9*4}3_{+ 3*4}2_{+ 1*4}1_{+ 4*4}0

and(a,b) 2 2 0 0

Returns 0.0 if either a or b are 0.0 Else returns 1.0

and(2.1,0.0) returns 0.0 or(a,b) 2 2 0 0

Returns 0.0 if both a and b are 0.0 Else returns 1.0

or(2.1,0.0) returns 1.0

not(a) 1 1 0 0 Returns 1.0 if a is 0.0 Else returns 0.0 not(0.3) returns 0.0

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,...) e

is evaluated. Then test is evaluated. As long as the test is not 0.0, the action statements (a1 to an) are evaluated, the inc statement is evaluated, and the test is evaluated again. The result is the result of the final action statement.

for(x=0,below(x,11),x=x+1,y=y+x) returns 55.0 (if y was initially 0.0)

many(expr,...) 1 Non_e 0 0

This function treats many subexpressions as a single object (function). It is mainly for the 'for' function.

for(many(j=5,k=1),above(j*k,0.001),many(j=j+ 5,k=k/2),0)