		AIRBORNE GEOPHYSICAL DATA

			CD-ROM

Survey name:                    Block "RAU"
Location:                       Yukon Territory
Job No.:                        7067
Client:                         ATAC Resources Ltd.
Survey date:                    August 12, 2007
Survey company name:            Geotech Ltd.

No. of Traverse lines:          37
No. of Tie lines:               4
Total line-km:                  149.73
Archive creation date:          January, 2007

Aircraft type:                  Astar 350 B2+, registration C-GTFX
Base of operation:              Mayo, YK

Airborne Magnetometer
Model:				Geometrics
Type:				Cesium-vapour
Sample Interval:		10 Hz (0.1 seconds); 2-3 metres
Sensitivity:			0.02 nT
Mount:                          Towed bird, 15 metres below helicopter
Height above ground:            180 metres  (nominal)

Airborne EM
Model:				Geotech Ltd.
Type:				VTEM
Number of channels:		25 (0.12-7.828 ms) off-time.
Sample Interval:		10 Hz (0.1 seconds); 2-3 metres
Mount:                          Towed ring, 35 metres below helicopter
Transmitter Loop diameter:	26.2 m
Transmitter Number of turns:	4
Current:                        201 Amp
Peak Dipole moment:             427400 NIA
Receiver Loop diameter:		1.1 m
Receiver number of turns:	100
Receiver effective area:	113.1 m2
Height above ground:		160 metres

Twenty-five time gates, from 120 microsecond to 7828 microsecond,
as following,

VTEM Decay Sampling scheme (Microseconds)
     Time gate	Start	End    Width
	120	110	131	21
	141	131	154	24
	167	154	183	29
	198	183	216	34
	234	216	258	42
	281	258	310	53
	339	310	373	63
	406	373	445	73
	484	445	529	84
	573	529	628	99
	682	628	750	123
	818	750	896	146
	974	896	1063	167
       1151	1063	1261	198
       1370	1261	1506	245
       1641	1506	1797	292
       1953	1797	2130	333
       2307	2130	2526	396
       2745	2526	3016	490
       3286	3016	3599	583
       3911	3599	4266	667
       4620	4266	5058	792
       5495	5058	6037	979
       6578	6037	7203	1167
       



Mean terrain clearance:         195 m nominal
Navigation type:		NovAtel's WAAS, OEM4-G2-3151W GPS receiver
				(on the tail of the helicopter)
Radar altimeter: 		Terra TRA3000/TRI-40


Block:                          RAU
Traverse line direction:        N0E / N180E
Traverse line spacing (m):      100
Tie line direction:             N90E/ N270E
Tie line spacing (m):           1000


                AIRBORNE GEOPHYSICAL DIGITAL ARCHIVES


There are two (2) main directories:

	Data		contains databases, grids and maps, as described below.

	Report		contains a copy of the report and appendices in PDF format.



Database in Geosoft GDB format, containing the following channels:

        X:              X positional data (metres  WGS84, utm zone 8 north)
        Y:              Y positional data (metres  WGS84, utm zone 8 north)
	Z:		GPS antenna elevation (metres - ASL)
	Radar:		Helicopter terrain clearance from radar altimeter (metres - AGL)
	Radarb:		EM Loop terrain clearance from radar altimeter (metres - AGL)
	DEM:		Digital elevation model (metres)
	Gtime1:		GPS time (seconds of the day)
	Mag1:		Raw Total Magnetic field data (nT)
	Basemag:	Magnetic diurnal variation data (nT)
	Mag2:		Total Magnetic field diurnal variation corrected data (nT)
	Mag3:		Leveled Total Magnetic field data (nT)
	SF[10]:		dB/dt 120 microsecond time channel (pV/A/m4)
	SF[11]:		dB/dt 141 microsecond time channel (pV/A/m4)
	SF[12]:		dB/dt 167 microsecond time channel (pV/A/m4)
	SF[13]:		dB/dt 198 microsecond time channel (pV/A/m4)
	SF[14]:		dB/dt 234 microsecond time channel (pV/A/m4)
	SF[15]:		dB/dt 281 microsecond time channel (pV/A/m4)
	SF[16]:		dB/dt 339 microsecond time channel (pV/A/m4)
	SF[17]:		dB/dt 406 microsecond time channel (pV/A/m4)
	SF[18]:		dB/dt 484 microsecond time channel (pV/A/m4)
	SF[19]:		dB/dt 573 microsecond time channel (pV/A/m4)
	SF[20]:		dB/dt 682 microsecond time channel (pV/A/m4)
	SF[21]:		dB/dt 818 microsecond time channel (pV/A/m4)
	SF[22]:		dB/dt 974 microsecond time channel (pV/A/m4)
	SF[23]:		dB/dt 1151 microsecond time channel (pV/A/m4)
	SF[24]:		dB/dt 1370 microsecond time channel (pV/A/m4)
	SF[25]:		dB/dt 1641 microsecond time channel (pV/A/m4)
	SF[26]:		dB/dt 1953 microsecond time channel (pV/A/m4)
	SF[27]:		dB/dt 2307 microsecond time channel (pV/A/m4)
	SF[28]:		dB/dt 2745 microsecond time channel (pV/A/m4)
	SF[29]:		dB/dt 3286 microsecond time channel (pV/A/m4)
	SF[30]:		dB/dt 3911 microsecond time channel (pV/A/m4)
	SF[31]:		dB/dt 4620 microsecond time channel (pV/A/m4)
	SF[32]:		dB/dt 5495 microsecond time channel (pV/A/m4)
	SF[33]:		dB/dt 6578 microsecond time channel (pV/A/m4)
	BF[10]:		B-field 120 microsecond time channel (pV*ms/A/m4)
	BF[11]:		B-field 141 microsecond time channel (pV*ms/A/m4)
	BF[12]:		B-field 167 microsecond time channel (pV*ms/A/m4)
	BF[13]:		B-field 198 microsecond time channel (pV*ms/A/m4)
	BF[14]:		B-field 234 microsecond time channel (pV*ms/A/m4)
	BF[15]:		B-field 281 microsecond time channel (pV*ms/A/m4)
	BF[16]:		B-field 339 microsecond time channel (pV*ms/A/m4)
	BF[17]:		B-field 406 microsecond time channel (pV*ms/A/m4)
	BF[18]:		B-field 484 microsecond time channel (pV*ms/A/m4)
	BF[19]:		B-field 573 microsecond time channel (pV*ms/A/m4)
	BF[20]:		B-field 682 microsecond time channel (pV*ms/A/m4)
	BF[21]:		B-field 818 microsecond time channel (pV*ms/A/m4)
	BF[22]:		B-field 974 microsecond time channel (pV*ms/A/m4)
	BF[23]:		B-field 1151 microsecond time channel (pV*ms/A/m4)
	BF[24]:		B-field 1370 microsecond time channel (pV*ms/A/m4)
	BF[25]:		B-field 1641 microsecond time channel (pV*ms/A/m4)
	BF[26]:		B-field 1953 microsecond time channel (pV*ms/A/m4)
	BF[27]:		B-field 2307 microsecond time channel (pV*ms/A/m4)
	BF[28]:		B-field 2745 microsecond time channel (pV*ms/A/m4)
	BF[29]:		B-field 3286 microsecond time channel (pV*ms/A/m4)
	BF[30]:		B-field 3911 microsecond time channel (pV*ms/A/m4)
	BF[31]:		B-field 4620 microsecond time channel (pV*ms/A/m4)
	BF[32]:		B-field 5495 microsecond time channel (pV*ms/A/m4)
	BF[33]:		B-field 6578 microsecond time channel (pV*ms/A/m4)
	PLM:		Power line monitor

	Electromagnetic B-field and dB/dt data is found in array channel format
        between indexes 10  33, as described above.



Grids in Geosoft GRD format, with grid cell size of 10 metres, as follow,

        MOR_magfin:	Total Magnetic field (nT)
        MOR_DEM :	Digital elevation model (Metres)

	A Geosoft .GRD file has a .GI metadata file associated with it,
	containing grid projection information.



Maps at 1:20,000 scale in Geosoft MAP format, as follow,

        Rau_Magfin:	Total Magnetic Field contours and colour image
        Rau_EMLP:    	VTEM B-field profiles, Time Gates 0.234 
        		7.828 ms  in linear - logarithmic scale
        Rau_DBDT:    	VTEM dB/dT profiles, Time Gates 0.234 
        		7.828 ms  in linear - logarithmic scale




Database 7067MOR_Wform.gdb in Geosoft GDB format, containing the following channels:

	Time:		Sampling rate interval, 10.416 microseconds
	Volt:		output voltage of the receiver coil (volt)



Google Earth file 7067_RAU.kmz showing the flight path of the block.

	Free version of Google Earth software can be downloaded from,
	http://earth.google.com/download-earth.html




Flown and processed by:			Geotech Ltd.
                                        245 Industrial Parkway North
                                        Aurora, Ontario, L4G 4C4
					Phone: 905.841.5004
					Fax:   905.841.0611
                                        www.geotech.ca

                                        January, 2008.
