
==========================================================================================
GENERAL
==========================================================================================

Project:      Heli EM Survey
Client:       MRT
Client Rep:   Bob Richardson
Survey By:    GEO Instruments
GEO Number    2113
Survey date:  January 2001 - May 2002
Survey Base:  Sheffield, Cradle Mt, Zeehan, Marrawah


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DATA ACQUISITION
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              AIRBORNE SURVEY SPECIFICATIONS

              Area A:                        Dolcoath
              Survey flown:                  January 2001 - April 2002
              Traverse line spacing:         200 metres
              Traverse line direction:       000 / 180 degrees
              Tie line spacing:              2000 metres approx
              Tie line direction:            090 / 270 degrees approx
              Survey height:                 EM towed Bird at 30m agl

              Area B.C,D:                    Meredith,Mt Reid Volcanics, Balfour
              Survey flown:                  January 2001 - April 2002
              Traverse line spacing:         200 metres
              Traverse line direction:       090 / 270 degrees
              Tie line spacing:              2000 metres approx
              Tie line direction:            000 / 180 degrees
              Survey height:                 EM towed Bird at 30m agl

              Electromagnetic System         Hummingbird 5 frequency EM system
              Resolution:                    1ppm
              Recording Interval:            0.1 sec (approx. 3.5 metres sampling)
              Data acquisition:              Geo Instruments Model G2002 system
                                             Geotech Hummingbird system
              Aircraft:                      AeroSpatiale Squirrel helicopter AS350BA

              MAGNETOMETER
              Type:                          Geometrics G822A Caesium vapour
              Resolution:                    0.001 nT
              Recording interval:            0.1 sec (approx. 3.5 metres sampling)
              Installation:                  Magnetometer sensor mounted in HEM bird.

              NAVIGATION
              Flight path navigation:        Real time satellite
                                             Differential GPS system
              Navigation equipment:          Fugro OMNISTAR GPS receivers
              Flight path record:            WGS84 Easting/ Northing coordinates

              Radar altimeter:               Collins Alt50
              GPS base station locations:    Fugro OMNISTAR(Real Time DGPS)


              HUMMINGBIRD COIL SPECIFICATIONS:

              Bird 1 - Between Julian day 31, 2001 to day 44, 2001
              Channel             :     1       2       3       4       5
              --------------------------------------------------------------
              Freq (Hz)           :     7000    6600    980     880     34000
              Orientation         :     CX      CP      CX      CP      CP
              Coil Separation (m) :     6.26    6.26    6.01    6.01    4.93


              Bird 2 - Between Julian day 310, 2001 Flight 1 to day 67, 2002, Flight 93
              Channel             :     1       2       3       4       5
              --------------------------------------------------------------
              Freq (Hz)           :     7000    6600    980     880     34000
              Orientation         :     CX      CP      CX      CP      CP
              Coil Separation (m) :     6.26    6.26    6.01    6.01    4.93


              Bird 3 - After Julian day 67, 2002, Flight 94 onwards
              Channel             :     1       2       3       4       5
              --------------------------------------------------------------
              Freq (Hz)           :     7000    6600    980     880     34000
              Orientation         :     CX      CP      CX      CP      CP
              Coil Separation (m) :     6.25    6.25    6.03    6.03    4.79


              TEST LINES:

              Dolcoath Line 082
              Start:              426183E, 5407428N  AGD66 Zone 55
              End:                426200E, 5411253N  AGD66 Zone 55

              Meredith
              Start:              410095E, 5399000N  AGD66 Zone 55
              End:                396279E, 5399000N  AGD66 Zone 55

              Mt Read
              Start:              363198E, 5361109N  AGD66 Zone 55
              End:                362989E, 5360756N  AGD66 Zone 55

              Balfour
              Start:              362981E, 5360736N  AGD66 Zone 55
              End:                363415E, 5363284N  AGD66 Zone 55


==========================================================================================
DATA PROCESSING
==========================================================================================

              MAGNETIC DATA
              The magnetic data has been corrected for regional gradient by
              subtraction of IGRF model 2001.9 and secular variation model
              1995-2000. Diurnal variations have been removed. System parallax
              has been removed. Tieline levelling has been applied.
              Microlevelling has been applied. The mean diurnal value and
              the IGRF base value have been added to the data.


              ELECTROMAGNETIC DATA
              The electromagnetic data has been filtered to remove the effects of
              sferics and other noise sources.  Data have been corrected for system
              drift by subtraction of background zero levels determined from high
              altitude callibration data.  System parallax has been removed.
              Apparent resistivities have been calculated using the Inversion techniques
              using the Geosoft HEM module.
              Inphase and quadrature channels have been levelled to remove residual
              flight line features in apparent resistivities.
              Microlevelling has been applied.

              34K CALIBRATION CORRECTION
              A systematic error was introduced in Bird #2 due to a change in the spacing
              between the 34Khz receive coil and position on the Calibration jig of the
              34kHz Q-Coil.
              Due to this, a measurement error in the distance between the 34k reciever coil
              and the Q coil during the calibration of the 34K channel, a special correction
              was applied to the data from Bird #1:

              from Flight  #1 11th Nov 2001 DOY 315
              to   Flight #93  8th Mar 2002 DOY 67

              From analysis of the Q coil response between the correct spacing and the
              incorrect spacing; The data were multiplied by the ratio 65/56. This correction
              was applied during the levelling phase in an intermediate processing step. The
              result gives the correct offset for the Q coil response at the correct spacing.
              This correction has not been applied to the raw data fields '_ppm' in the
              database. Please refer to Appendix 5 of the Operations and Processing Report for
              examples of this correction.


              GRIDDING - Electromagnetics-   Inphase & quad
              Algorithm:                     Minimum Curvature
              Grid mesh size:                40 x 40 metres
              Grid filter:                   None

              GRIDDING - Electromagnetics-   Resistivities & Conductivity
              Algorithm:                     Minimum Curvature
              Grid mesh size:                40 x 40 metres
              Grid filter:                   none

              GRIDDING - Magnetics:
              Algorithm:                     Minimum Curvature
              Grid mesh size:                40 x 40 metres
              Grid filter:                   None

              GRIDDING - Digital Terrain:
              Algorithm:                     Minimum Curvature
              Grid mesh size:                40 x 40 metres
              Grid filter:                   3x3 mean


              LINE NUMBERING
              Line numbers are in the form 'TLLLA' where
              T = Line type (1 = traverse, 7 = tie)
              LLL = Line sequence number
              A = Line attempt number

              eg: 10021 is traverse line 2 attempt 1
                  70482 is tie lie 48 attempt 2


              BIBLIOGRAPHIC REFERENCE
              Surveyed by:                   GeoInstruments Pty Ltd
              Geo Instruments job number:    2113
              Processed by:                  GeoInstruments Pty Ltd
              Grid production by:            GeoInstruments Pty Ltd




==========================================================================================
EM DATA:
==========================================================================================
Nomenclature for field name / processing relationship:

'_ppm'        Raw data:
'_F_L'        Filtered and levelled data.
'_F_LD'       Filtered, levelled and microlevelled data.
'_AResistINV' Apparent Resistivity ohms/m calculated using the INVERSION technique.
'_ACondINV'   Apparent Conductivity uS/m calculated using the INVERSION technique.


==========================================================================================
GRIDDED DATA FILES:
==========================================================================================
Files:        Extensions as for processed data above.
Format:       ER Mapper
Cell size:    40 metres


==========================================================================================
FINALS:
==========================================================================================
Datum:        AGD66
Projection:   TMAMG
Zone:         55


==========================================================================================
LOCATED DATA FORMAT:
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------------------------------------------------------------------------------------------
Field         Field Name          Description
------------------------------------------------------------------------------------------
Column  1     LineNo_TLLLA        line number (TLLLA)
Column  2     FlightNo            flight
Column  3     Julian_Day          julian_day  (YYYYDDD)
Column  4     Fid_geo             fiducial- Geoinstruments acqusition system
Column  5     Fid_humm            fiducial- HEM acqusition system
Column  6     Time_hh             time (decimal hours)
Column  7     AGD66TMAMG55_East   AGD66 easting  (metres, TMAMG Zone 55)
Column  8     AGD66TMAMG55_North  AGD66 northing (metres, TMAMG Zone 55)
Column  9     GDA94MGA55_East     GDA94 easting  (metres, MGA Zone 55)
Column 10     GDA94MGA55_North    GDA94 northing (metres, MGA Zone 55)
Column 11     AGD66GEODETIC_LAT   AGD66 longitude (decimal degrees, GEODETIC)
Column 12     AGD66GEODETIC_LONG  AGD66 latitude  (decimal degrees, GEODETIC)
Column 13     GDA94GEODETIC_LAT   GDA94 longitude (decimal degrees, GEODETIC)
Column 14     GDA94GEODETIC_LONG  GDA94 latitude  (decimal degrees, GEODETIC)
Column 15     Mag_Raw             Raw uncompensated magnetics (nanoTeslas)
Column 16     GPSalt_Raw          Raw GPS height (metres)
Column 17     Radalt_Raw          Raw radar altimeter (metres)
Column 18     Diurnal             Diurnal magnetics (nanoTeslas)
Column 19     IGRF                IGRF magnetics (nanoTeslas)
Column 20     TMI_Corrected       Diurnal & IGRF corrected magnetics (nanoTeslas)
Column 21     TMI_Levelled        Levelled magnetics (nanoTeslas)
Column 22     TMI_Final           Final magnetics microlevelled (nanoTeslas)
Column 23     GPSalt_Final        Final GPS height (metres, AHD)
Column 24     Radalt_Final        Final Radar altimeter (metres)
Column 25     DTM_Final           Final digital terrain model (metres, AHD)
Column 26     cx7Ki_PPM           Raw cx7Ki (ppm)
Column 27     cx7Kq_PPM           Raw cx7Kq (ppm)
Column 28     cp6Ki_PPM           Raw cp6Ki (ppm)
Column 29     cp6Kq_PPM           Raw cp6Kq (ppm)
Column 30     cx980i_PPM          Raw cx980i (ppm)
Column 31     cx980q_PPM          Raw cx980q (ppm)
Column 32     cp880i_PPM          Raw cp880i (ppm)
Column 33     cp880q_PPM          Raw cp880q (ppm)
Column 34     cp34ki_PPM          Raw cp34ki (ppm)
Column 35     cp34kq_PPM          Raw cp34kq (ppm)
Column 36     cx7Ki_F_L           Filtered & Levelled cx7Ki (ppm)
Column 37     cx7Kq_F_L           Filtered & Levelled cx7Kq (ppm)
Column 38     cp6Ki_F_L           Filtered & Levelled cp6Ki (ppm)
Column 39     cp6Kq_F_L           Filtered & Levelled cp6Kq (ppm)
Column 40     cx980i_F_L          Filtered & Levelled cx980i (ppm)
Column 41     cx980q_F_L          Filtered & Levelled cx980q (ppm)
Column 42     cp880i_F_L          Filtered & Levelled cp880i (ppm)
Column 43     cp880q_F_L          Filtered & Levelled cp880q (ppm)
Column 44     cp34ki_F_L          Filtered & Levelled cp34ki (ppm)
Column 45     cp34kq_F_L          Filtered & Levelled cp34kq (ppm)
Column 46     cx7Ki_F_LD          Final Levelled cx7Ki (ppm)
Column 47     cx7Kq_F_LD          Final Levelled cx7Kq (ppm)
Column 48     cp6Ki_F_LD          Final Levelled cp6Ki (ppm)
Column 49     cp6Kq_F_LD          Final Levelled cp6Kq (ppm)
Column 50     cx980i_F_LD         Final Levelled cx980i (ppm)
Column 51     cx980q_F_LD         Final Levelled cx980q (ppm)
Column 52     cp880i_F_LD         Final Levelled cp880i (ppm)
Column 53     cp880q_F_LD         Final Levelled cp880q (ppm)
Column 54     cp34ki_F_LD         Final Levelled cp34ki (ppm)
Column 55     cp34kq_F_LD         Final Levelled cp34kq (ppm)
Column 56     cp34k_AResistINV    Apparent cp34k Resistivity (ohms/m) INVERSION technique.
Column 57     cp6k_AResistINV     Apparent cp6k  Resistivity (ohms/m) INVERSION technique.
Column 58     cp880_AResistINV    Apparent cp880 Resistivity (ohms/m) INVERSION technique.
Column 59     cx7K_AResistINV     Apparent cx7K  Resistivity (ohms/m) INVERSION technique.
Column 60     cx980_AResistINV    Apparent cx980 Resistivity (ohms/m) INVERSION technique.
Column 61     cp34k_ACondINV      Apparent cp34k Conductivity (uS/m) INVERSION technique.
Column 62     cp6k_ACondINV       Apparent cp6k  Conductivity (uS/m) INVERSION technique.
Column 63     cp880_ACondINV      Apparent cp880 Conductivity (uS/m) INVERSION technique.
Column 64     cx7k_ACondINV       Apparent cx7K  Conductivity (uS/m) INVERSION technique.
Column 65     cx980_ACondINV      Apparent cx980 Conductivity (uS/m) INVERSION technique.


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LOCATED DATA FILES:
==========================================================================================

              Final:           ASCII ASEG_GDF located data
              Archive Media:   Exabyte

              Area1_Dolcoath_Granite.dat
              Area1_Dolcoath_Granite.dfn
              Area1_Dolcoath_Granite_Lines_Report.txt

              Area2_Meredith_Granite.dat
              Area2_Meredith_Granite.dfn
              Area2_Meredith_Granite_Lines_Report.txt

              Area3_MtRead_Volcanics.dat
              Area3_MtRead_Volcanics.dfn
              Area3_MtRead_Volcanics_Lines_Report.txt

              Area4_Balfour.dat
              Area4_Balfour.dfn
              Area4_Balfour_Lines_Report.txt

              TAS_HEM_Readme.txt

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