Gravity import file formats (R27)
Contents
1. datum Gravity datum for the station data Tip Note the datum field here is the only way of specifying the theoretical gravity model for the data Scintrex import file notes Library Help Top Preparing Scintrix data import Prepare the Scintrex import files as follows 1 Ensure that you have unique 4 digit station numbers 2 Set the Line field to the survey number Note INTREPID ignores some fields in the gravity observation data file See the Scintrex CG3 Autogravimeter manual for a full explanation of this file As you acquire more survey data over the course of the survey you can incorporate it into the gravity dataset Append each additional Scintrex file to the previous file using a text editor Gravity import data Just dump the data straight from the meter Can cope with different versions of the meter for example V 4 7 5 2 Each group of data has a header that includes Line User Meter Number Date For a given line Meter Date and User if there are multiple groups these are concatenated into a logical loop for the current gravity meter loop set Lines Nos 1 9 are reserved for Base Station observations or to tie into the AGSO network These readings are detected on input and concatenated around the gravity line data for the same date Up to 9 base in outs are supported for the same day using this convention Grid style survey design This is supported where Line Number is usually North2. LCR_G AFFB LCR_D LCR_DD LCR_DD_MVR 3 Gravimeter number G132 4 Observer HReith 5 Nominal scale factor 1 000214 CALRUN 2 Calibration loop number 323 01 3 Time difference from UTC 11 Library Help Top 2012 Intrepid Geophysics lt 4 Back gt INTREPID User Manual Gravity import file formats R27 6 Library Help Top 4 Back gt Keyword Field Field Description Example or Possible values station number 1 Station number of reading 80900143 2 Year 1996 3 Month 11 4 Day 18 5 Time 0 345138889 6 Dial reading 2925 549 T Digital voltmeter reading This is used 0 for fine adjustment INTREPID applies a scale factor depending on the meter type and adds the result to the dial reading 8 Distance from top of meter in mm delta 0 H 9 Barometric pressure 0 10 Temperature 0 11 Comments between large trees More readings More loops More gravimeters Library Help Top Contact our technical support service if you require support for other gravimeters 2012 Intrepid Geophysics 4 Back gt INTREPID User Manual Gravity import file formats R27 7 Library Help Top 4 Back gt Scintrex import file format Import file overview Library Help Top This format requires three files Gravity data from the meter The data for the CG3 and CG5 are in different format See Gravity data from meter CG3 Gravity data from
3. 896 0 000 0 0 0 0 0 MERYULA 96040001 1996 11 19 9 08 00 2852 179 0 000 0 0 0 0 0 0 hill curve 96040002 1996 11 19 9 12 00 2853 598 0 000 0 0 0 0 0 0 x cobar a p 0 0 called 9601 in gps Library Help Top 2012 Intrepid Geophysics lt 4 Back gt INTREPID User Manual Gravity import file formats R27 3 Library Help Top 4 Back gt Structure of the import file The following table describes these fields For lines commencing with a keyword the keyword is field 1 so the remaining fields commence at number 2 Keyword Field Field Description Example or Possible values SURVEY 1 Survey header 2 Survey number 9604 3 Descriptive title Cobar Detailed Traverses NSW POSITION 1 Gravity station definition 2 Coordinate reference 3 Ellipsoid ANS 4 Datum AGD66 5 Height datum AHD 6 Projection Geodetic 7 Position accuracy distance units orm 0 8 Elevation accuracy m 0 02 station number 1 Station number 96040001 2 Longitude or X coordinate 03 07 3 3 Latitude or Y coordinate 31 31 26 36739 4 Altitude m 252 996 5 Name of station Boyles tank More station positions More station position blocks Library Help Top 2012 Intrepid Geophysics 4 Back gt INTREPID User Manual Gravity import file formats R27 4 Library Help Top lt 4 B
4. It is optional to give a LINE number If you do you produce a line or profile database rather than a random point data base Station must correspond with the Gravity station number in the data file You can enter either geodetic or projected coords in Scintrex format Examples of GPS files NAME LATITUDE LONGITUDE HEIGHT 1321 37 75000000 148 45000000 100 000 9 37 64748908 148 06730520 112 710 2012 Intrepid Geophysics 4 Back gt INTREPID User Manual Gravity import file formats R27 8 Library Help Top Station Easting Northing Elevation 14 463244 316 5770311 886 77 386 15 463272 101 5770323 312 76 829 16 463299 808 5770334 751 76 198 Control station information These files have the extension ABS The Control station file has the following format Station number tie in observed gravity Absolute Datum You can have as many control stations as you like Example of Control Station file 1000 979269 241 IGSN71 11000 979269 241 IGSN71 The units are the same as chosen in the Mode box Gravity observation data file for SC3 DAT This file contains the gravity data as recorded lt 4 Back gt 266 5 276 3 30 8 119 5 8 hr 12 Wen 10 00 41 10 03 28 10 06 35 10 08 37 10 10 26 10 13 00 10 16 06 10 18 25 10 21 02 10 22 45 Example SCINTREX V5 0 AUTOGRAV Field Mode R4 4 Ser No 610353 Line 9750 E Grid 1 Job 892 Date 98 02 05 Operator GREF 0 mGals Tilt x sensit GCAL
5. You can replace the number with the operator name in the processing report using a text editor if required Library Help Top 2012 Intrepid Geophysics lt 4 Back gt INTREPID User Manual Gravity import file formats R27 10 Library Help Top lt 4 Back gt Gravity da ta format Station Grav SD Tilt x Tilt y Temp E T C Dur Rej Time 1000 N 4205 608 0 047 0 1 0 06 0 070 40 O 10 00 41 Field Description Station Station number field We recommend that you follow the four digit AGSO convention A maximum of five digits is possible for the station number Do not use zero as the first digit The Scintrex gravimeter will place a decimal and letter after the digit survey number following its line naming convention INTREPID only imports the four digit number Grav Dial reading of the Scintrex gravimeter in mGal is present when the tilt correction parameter is set consult the CG3 operators manual for details INTREPID ignores this symbol SD If there is only one reading for the station INTREPID uses this value to report Tilt x Tilt y Temp ETC Dur Rej Time error and calculate the observed gravity error obsgerror field in the dataset If there are several readings INTREPID ignores this field INTREPID does not use these fields The Scintrex meter can automatically apply an Earth tide correction ETC to the dial reading consult the CG3 operators manual for details If the gravimeter appl
6. geodetic data These can be in decimal degree format or degree minute second format easting northing Coordinates of the gravity station projected data You must specify the projection in the Gravity tool during import INTREPID converts the data to geodetic Network control station file ABS Library Help Top This file defines the network control station data This can be An absolute station where the absolute gravity value has been determined by pendulum or interferometry experiments or A network control station with value relative to some standard or an arbitrarily assigned value Example 80999998 9793892 6 ISOGAL80 Format INTREPID uses the station on the first line as the network control station Any stations on following lines are for reference or for use in other work by editing the file to bring them to the top The fields are space delimited and there is no first line with field names 2012 Intrepid Geophysics 4 Back gt INTREPID User Manual Gravity import file formats R27 12 Library Help Top lt 4 Back gt The data has the following format stationnumber controlstation datum Field Description stationnumber Station number identical to the corresponding four digit station number in the gravity observation data and gravity station location file controlstation Gravity value for the station in the same units as the gravity observation data file
7. 1 6400 428 Tilt y sensit GCAL 2 0 Deg Latitude TEMPCO 0 1235 mGal mK Deg Longitude Drift const 0 55 GMT Difference Drift Correction Start Time 11 40 40 Cal after x samples Date 98 01 26 On Line Tilt Corrected Station Grav SD Tilt x Tilt y Temp E T C Dur Rej 1000 N 4205 608 0 047 0 L 0 06 0 070 40 0 1025 N 4205 540 0 053 5 2 0 06 0 069 40 0 1050 N 4206 589 0 044 1 4 0 06 0 068 40 0 1075 N 4207 339 0 054 3 4 0 05 0 067 40 1 1100 N 4207 744 0 041 0 2 0 05 0 066 40 0 1125 N 4207 791 0 049 2 1 0 06 0 065 40 0 1150 N 4207 725 0 046 2 1 0 05 0 064 40 0 1175 N 4207 617 0 042 7 4 0 05 0 063 40 0 1200 N 4207 479 0 052 1 8 0 05 0 061 40 0 1225 N 4207 466 0 054 2 3 0 05 0 061 40 0 Library Help Top 2012 Intrepid Geophysics lt 4 Back gt INTREPID User Manual Gravity import file formats R27 9 Library Help Top lt 4 Back gt File header format SCINTREX V5 0 AUTOGRAV Field Mode R4 4 Ser No 610353 Line 9750 E Grid 1 Job 892 Date 98 02 05 Operator 1 Field Description Ser No The serial number of the gravimeter INTREPID uses this to define a GMLS Date Day month and year of the gravity station reading Line INTREPID uses this field if the Gravity station location file GPS file uses it See GPS data input below Grid INTREPID does not use this field Operator Operator number We recommend that you document the name of the operator associated with this number
8. INTREPID User Manual Gravity import file formats R27 1 Library Help Top lt 4 Back gt Gravity import file formats R27 Top In this chapter AGSO import file format Scintrex import file format AGSO import file format A single flat ASCII file structure Has the advantage that all the data is in one place and will survive the test of time for archival purposes All data including positions control stations and calibrations are included in this file Examples of the AGSO format can be found in your INTREPID installation in sample_data cookbooks gravity land AGSO_Week1 amp 2 DAT Description The import file consists of lines of text describing gravity stations and the sequence of readings taken at them The lines of the contain a number of fields separated by commas Lines commencing with the keywords SURVEY POSITION GRAVITY GRAVIMETER determine the structure of the file These lines identify and contain data common to blocks of individual station data or readings Each individual reading or station specification is on a separate line following one of these keyword lines Lines starting with are comment lines INTREPID ignores them You can force INTREPID to ignore a line by placing a at the start Note For an example of calibration data see Gravimeter calibration R29 Here is part of a gravity import file An example import file SURVEY 9604 Cobar Detailed Traverses New South Wales Gravity Stat
9. South co ordinate and Station number is East West The Program currently ignores N S and E W annotations except for reporting 2012 Intrepid Geophysics 4 Back gt INTREPID User Manual Gravity import file formats R27 13 Library Help Top Library Help Top 4 Back gt GPS data input Must supply GPS locations for all stations except fixed nodes and base IN OUT nodes for a loop This is a free format multi column ASCII file that has a mandatory header Three normal conventions for the header labels are Station Easting Northing Elevation Station longitude latitude Elevation Station line longitude latitude Elevation Where Station and Line can be interchanged and either Easting and Northing or longitude and latitude can be interchanged e Ifthe Station Line convention is used the user is assumed to be following a grid style gravity survey Where Station is E W line is N S If station only GPS data convention is used the station number is derived by the Gravity line 10 000 station number For example Line 9750 Station 1000 becomes station 97501000 for the GPS data and for internal processing INTREPID lists line and station separately in 16 Final values in Gravity corrections T54 Tie In to National Grid Data A GPS data record is edited to create the tie in link to an AGSO or National Grid where an absolute or control value is available This accomplished using an optional a
10. ack gt Keyword Field Field Description Example or Possible values GRAVITY 1 Control Gravity Reference 2 Gravity datum Potsdam ISOGAL65 ISOGAL80 IGSN71 station number 1 Station number 80900143 2 Control gravity value 9793892 6 3 Accuracy of gravity value 0 1 4 Name of station Cobar Airport More control stations More control station blocks GRAVIMETER 1 Gravimeter Loop Set 2 Gravimeter type Scintrex LCR_G LCR_G_AFFB LCR_D LCR_DD LCR_DD_MVR 3 Gravimeter number G132 4 Observer HReith 5 Nominal scale factor 1 000214 LOOP 2 Loop number 323 01 3 Time difference from UST 11 Library Help Top 2012 Intrepid Geophysics 4 Back gt INTREPID User Manual Gravity import file formats R27 5 Library Help Top 4 Back gt Keyword Field Field Description Example or Possible values station number 1 Station number of reading 80900143 2 Year 1996 3 Month 11 4 Day 18 5 Time fraction of day 0 345138889 6 Dial reading 2925 549 7 Digital voltmeter reading This is used 0 for fine adjustment INTREPID applies a scale factor depending on the meter type and adds the result to the dial reading 8 Distance from top of meter in mm delta 0 H 9 Barometric pressure 0 10 Temperature 0 11 Comments between large trees More readings More loops More gravimeters CALIBRATION 1 Calibration Data For Gravimeter 2 Gravimeter type LCR_G
11. ddition to the station A convention of aliasing an AGSO style station number after a slash is used for example 1570 956359 The first number is the internal station number The number following the slash is the AGSO style station number for the same location This is supported for all the GPS data input variations The required control stations values can be input using the third ASCII file The convention is Station Value Gravity Datum one observation per record in free format For example 88001236 975630IGSN71 93216321 977544IGSN71 Other Issues Treatment of internal loop repeat readings It is now optional to use reports to make adjustments to the short term linear drift Calibration The concept of calibrating or checking the calibration of a Scintrex meter is more complicated than for the older style LaCoste amp Romberg meters The Intrepid calibration option is geared for the L amp R first order correction It is more usual to follow Scintrex s recommended calibration procedures and re calibrate the instrument on a range and store the first order fixes internal to the meter 2012 Intrepid Geophysics 4 Back gt
12. ies this correction INTREPID removes it and applies its own Earth tide correction INTREPID does not use these fields Time of gravity reading INTREPID converts hours minutes seconds format into hours Gravity station location file GPSs Library Help Top This file contains station number and location for each survey gravity station and control base station You may only have one record per station in this file If you have multiple GPS readings edit the file to remove the duplicates Example line stationeastingnorthingelevation 9750 1000 743550 401 6584501 617394 38 9750 1025 743570 723 6584515 289394 97 9750 1050 743590 142 6584529 848390 76 9750 1075 743611 931 6584542 455388 19 2012 Intrepid Geophysics 4 Back gt INTREPID User Manual Gravity import file formats R27 11 Library Help Top lt 4 Back gt Format The first line of this file defines the import fields For example line name longitude latitude height or line name easting northing height The fields are separated by free spaces The columns may be in any order The blocks of data must follow the order shown in the header line The following table gives a description of each field Field Description line Set this field to the survey number See GPS data input below name Station number identical to the four digit station number in the gravity observation data file longitude latitude Coordinates of the gravity station
13. ions POSITION UNKNOWN ANS AGD66 AHD GEODETIC 0 000001 0 020 96040001 146 3 7 34588 31 31 26 36739 252 996 96040002 146 2 52 65521 31 31 24 67920 244 491 96040003 146 2 37 63321 31 31 22 87273 241 373 Control Gravity Stations POSITION UNKNOWN ANS AGD66 AHD GEODETIC 0 0001 0 1 50999943 145 50 06 31 30 06 241 06 64910143 145 47 54 31 32 30 217 98 GRAVITY ISOGAL84 80900143 9793892 6 0 1 Cobar Airport Terminal 64910243 9793834 0 0 1 Cobar PM4917 Library Help Top 2012 Intrepid Geophysics lt 4 Back gt INTREPID User Manual Gravity import file formats R27 2 Library Help Top lt 4 Back gt GRAVITY ISOGAL65 50999943 979396 20 0 01 Cobar Police Station 64910143 979403 15 0 01 Cobar Airport on Sign Gravity Survey Data GRAVIMETER LCR_G G132 HReith 1 000214 LOOP 323 01 11 80900143 1996 11 18 08 17 00 2925 549 0 000 0 0 0 0 0 0 BAR AIRPORT 96042009 1996 11 18 13 23 00 2912 391 0 000 0 0 0 0 0 0 96041000 1996 11 18 13 43 00 2912 052 0 000 0 0 0 0 0 0 80900143 1996 11 19 19 12 00 2925 477 0 000 0 0 0 0 0 0 LOOP 325 02 11 80900143 1996 11 20 08 05 00 2925 448 0 000 0 0 96041105 1996 11 20 08 53 00 2927 949 0 000 0 0 80900143 1996 12 01 16 13 00 2925 026 0 000 0 0 0 0 0 0 GRAVIMETER LCR_G G101 PWynne 1 002932 LOOP 324 01 11 80900143 1996 11 19 7 59 00 2866 978 0 000 0 0 0 0 0 96229601 1996 11 19 9 04 00 2852
14. meter CG5 Formatted GPS position data e Control station information Examples of the Scintrex CG3 format can be found under the INTREPID installation in sample_data cookbooks gravity land SCINTREXAMPLE1 DAT SCINTREXAMPLE1 GPS SCINTREXAMPLE1 ABS Earth tides are always removed from the meter data and re calculated by INTREPID Gravity data from meter CG3 For CG3 the data file is in ASCII format These files have the extension DAT Line 0 is reserved for special use to capture base station readings on any one day If you use a Line 0 the basestations do not need to be included in the loop records The loop is reconstructed by looking at the time day etc Line 0 must be first in a sequence Alternatively loops are constructed by using the Line number as a Loop number If the Line number Meter number and day are identical on blocks of data it is assumed that the data all forms part of the same loop Gravity data from meter CG5 For CG5 the data file is in binary format sgd file Under File there is a Dump Check option which will convert the binary sgd file to an ASCII file This allows the user to review the various survey record headers in the data in the event that the meter contains data from different surveys Intrepid supports the import of multiple sgd files via a list of survey files Formatted GPS position data These files have the extension GPS The GPS file must have a header containing standard field names
Download Pdf Manuals
Related Search