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  • 7/28/2019 2dloadFromSMT

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    2D SEISMIC DATA LOADING

    2D data is usually provided by vendors on 8 mm tape in SEGY format. The following 5 steps allow the user to read the tapeafter dumping the contents to disk. Reading the headers becomes necessary because, oftentimes, one must find the line andshot point numbers, and X-Y coordinates from the SEGY file. User the SEGY Viewer to dump the tape.

    1. Some basic information is often available from the seismic line that we want to load. Data may be printed on the labelattached to the tape, on base maps, or on a hard copy of the 2D seismic line.

    2. Insert the tape in the tape drive. From the Kingdom Suite, double click on the SEGY Viewer icon and the Viewer screen

    will appear.3. Left click on File, then left click Read Exabyte Tape.4. The Define Load Parameters dialog box appears. Since we will dump more than one 2d SEGY file, to differentiate the

    files, give the first SEGY data set a unique 4 letter code. In the box next to Output File Prefix double click in the box, thedefault SEGY will be highlighted. Type inSeg1.

    5. In the box at the bottom of the Define Load Parameter Screen, under Drives, select the drive where the folder Schoolresides by left clicking on the arrow to activate the pull down list of drives. In the box above, double click on the folderschool, double click on the subdirectory Data, double click on 2D. Click OK. The tape drive will start to read thetape and dump the file(s) to disk. (For very large volumes, this process could take several hours.)

    This process is used if basic information on the 2d data is unknown. If all pertinent information is known, the files can be readinto the software directly, omitting this intervening step.

    EXAMINING THE SEGY FILES

    1. From the menu bar at the top of the Viewer screen, left click File, then left click Open. Under the Look in box, left click onthe arrow and from the pull down list, click on the drive where the SEGY file was stored. In the Directories box above,double click on the School, Data, then 2D. Double click on the file name where it appears again in the File Name box.Left click OK.

    2. Three new screens appear. Seg1*.sgy SEGY Text Header (EBCIDIC), Seg1*.sgy SEGY Binary Header (Normal), andSeg1*.sgy Trace Header No 1 (SEGY Standard Format).

    3. Look at the contents of the SEGY Text Header by left clicking on the title bar. Note the contents. C1 indicates comment1, C2 is comment 2, etc. In C1, the Client is Fairfield Ind.; C2 indicates the line number., C4 indicates the CDP location isin byte 21, C5 reveals the X coordinate in byte 73, and CDP-Y coordinate in byte 73, etc.

    4. Bring the SEGY Binary Header screen forward by left click on its title bar. Note some information.Line number 75535 (a different line number, assume line 2)No. of data traces/record: 100Sample interval: 4 (4 milliseconds)Number of samples/trace: 1750 (.004 x 1951-1 = 7.0 seconds of data)Format code(1=flt32,2=int32,3=int16, 5=int8) 1 (floating 32 bit data)CDP fold: 1Measurement system(1=metric, 2=feet): 2

    Iconize this screen by left clicking on down arrow, upper right side of title bar.

    GETTING AROUND IN THE TRACE HEADER SCREENS1. You are looking at the first trace header of the main body of data. Left click on the thin down arrow button - to see Trace

    Header No 2. Left click on thin up button - back up to Trace Header No 1.2. Left mouse click on the heavy down arrow next to the box with 10 - the screen now shows Trace Header No. 11. (If you

    changed the number in this box to 50, you could see every 50th

    trace header). Left click on the heavy up arrow next to thebox with 10 - back up to Trace Header No. 1.

    3. Left click on the heavy down arrow with the heavy bar. You have moved to the last trace header, Trace Header No 281.Note that word 01=281. This word equals the trace number. Words 05 and 21 also equal the trace number. Words 73and 77, 81 and 85 contain the x and y coordinates.

    STARTING 2D/3DPAK1. From the Kingdom Suite, double mouse click on the Kingdom-Seismic big red S icon. The Kingdom Suite screen

    appears.2. Left click on Project (See item 5. Note), left click on Open. The Open screen appears.3. Under Drives, select the drive where the folder School resides by left clicking on the arrow to activate the pull down list of

    drives, then left click on drive X. In the Directories box above, double click on the folder School .4. In the large box to the left, left click on school.prj. It is repeated in the small File Name block. Left click OK.

    Dhh/mre: 1/9/2008

    5. Note: If this was the last project that was active, the path?\school\school.prj will be listed in the Project pull downmenu. If it is, left click on the project path to start up the project.

    Seismic Micro-Technology, Inc.

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    2D SEISMIC DATA LOADING

    METHOD 1 - LOADING 2D LINE - SEGY TRACES & COORDINATES SEPARATELY (Load Line 2)Use this method if the coordinate information is not in the trace headers and you have separate coordinate data files.

    1. From the Kingdom Suite-Basemap bar, left click on Surveys. Left click on Load SEGY Traces. A pop-up menu willappear to the right. Left click on Load SEGY Traces..

    2. The Load SEGY Traces screen appears. Left click on the down arrow of the Select Survey line. Left click on Create new

    2D survey(s).3. Under Drives, select the drive where the folder School resides by left clicking on the arrow to activate the pull down list ofdrives, then left click on drive X. In the Directories box above, double click on the folder School, double click on thefolder 2D .

    4. The .sgy files appear in the left large box. Left click onSeg1Lin2.sgy. and it appears again in the small box above.5. The Select Seismic Data Type screen appears. We are loading amplitudes so the default data type is correct. Left click

    OK.6. The Input File screen appears. In the Survey Line type the line name2. Left click OK.7. The Kingdom Suite ! message World coordinates must be.. screen appears. (you will do this step later). Left click OK.8. The Define Trace Numbers screen appears. Under Load Trace Numbers, left click on CDP Number in Header button. In

    the Starting Byte: line type 21. Left click on the 32-bit button. Left click OK.9. Set Time Data Bounds screen appears. It confirms that the sample rate is .004, etc. (Note that there is an Advanced

    button here that is not needed in this load). Left click OK.10. Seismic Data Directory appears. VERY IMPORTANT to left click on 8-Bit button. Note how the Space Required value

    changes. Left click OK.

    11. The loading screen appears briefly (depending on how large the file is).12. Kingdom Suite ! screen appears telling us it loaded line 2, it loaded 281 traces, it skipped 0 traces (a good indication that

    the file is clean), and other amplitude data. Left click OK.13. Again, the Kingdom Suite ! message World coordinates must be.. screen appears. Left click OK.14. To load world coordinates, left click Surveys, left click World Coordinates, left click File Input15. The Select Coordinate Files screen appears. Left click on down arrow across from Select Survey and left click on 2.16. Under Drives, select the drive where the folder School resides by left clicking on the arrow to activate the pull down list of

    drives, then left click on drive X. In the Directories box above, double click on the folder School, double click on thefolder 2D .

    17. The file we will input is in UKOAA or .uko format. In bottom left corner, left click on down arrow, left click on UKOOA(*.uko). The .uko files will appear in the large box. Left click on Lin2rev.uko and it repeated in the small box under FileName. Left click OK.

    18. Kingdom Suite ! message asks Do you wish to load SEGY data now? You have already loaded it. Left click NO.19. The Basemap now has seismic line 2 displayed. (shot point 1,11,21, etc.)20. Last step. Left click on Surveys, left click on Assign Shot Points for 2D Surveys. Its screen appears.21. Across from Survey the line number 2 should be in the box. (if not, left click on down arrow and select it.)22. The button next to Define by starting is highlighted. Our trace header indicates that there is one trace per shot point and

    that the starting shot point is 1. Change the Traces per Shot Point to 1. Left click OK. Note that the numbering on theMap has changed (1,10,20,30, etc.).

    METHOD 2 - LOADING 2D LINE - SEGYTRACES & COORDINATES TOGETHER (Load line 3)Use this method if the trace header contains all data.

    1. From the Kingdom Suite-Basemap bar, left click on Surveys. Left click on Load SEGY Traces. A pop-up menu willappear to the right. Left click on Bulk Load 2D SEGY Traces with Coordinates - its screen appears.

    2. The Load SEGY Files from: Disk button is selected. Left click on Browse.3. Under Drives, select the drive where the folder School resides by left clicking on the arrow to activate the pull down list of

    drives, then left click on drive X. In the Directories box above, double click on the folder School, double click on the

    folder 2D .4. The .sgy files appear in the left large box. Left click onSeg4Lin3.sgy. and it appears again in the small box above. Left

    click OK.5. Left click on Setup. Its screen appears. Note that the default in Amplitudes. Left click OK.6. Left click Next.7. The SEGY File Parameters screen appears. Review the defaults. Seismic Line Name is OK. (Seismic Line Name in

    Row 2 is correct - loading line 3).8. In this case the Shot Point is the same as the CDP number which appears in Byte: 21. Double click in the box across

    from Shot Point Starts in Byte: and type in21.

    Dhh/mre: 1/9/2008Seismic Micro-Technology, Inc.

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    2D SEISMIC DATA LOADING

    9. The X-Coordinate Starts in Byte: 73 - the default is correct.10. The Y-Coordinate Starts in Byte: 77 - the default is correct.11. All of the Format buttons indicate 32-bit input data, the default is correct.12. The Seismic Datum Elevation is 0. The default is correct.13. The Datum Velocity is 0. The default is correct.14. Left click Next. The Loaded Information screen appears.15. VERY IMPORTANT Left click on Output Data Format as 8-bit if you want to save room on your hard drive.

    16. Left click on Finish. A loading screen briefly appears. Then the new line appears on the base map.

    (At this point, using method 2, two other lines could be loaded for practice).

    Dhh/mre: 1/9/2008Seismic Micro-Technology, Inc.

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