Index of /mrtdoc/airborne/sheffield1981/releveld/AGD66/ASCII

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Sheffield
ECSI Project b1042 - FLown 1981

Sheffield survey was flown by DIGHEM Pty Ltd. The client company is unknown.
The survey has been restored from ECS archives and reloaded into a data base.
There were two channels magnetics, radar altimeter. There are no tie lines in
the data set.

The original data was provided in two parts representing a western sheet area
and an eastern sheet area. The overlap area contained the same parts of
traverses but with different sets of located points. When these two sections of
overlap were merged, they formed a zig-zag pattern which is patently incorrect.
Thus for the merge area, the western line was treated as fact and the second
version of the line was added only where it didn't overlap - ie it was only
added where it extended the western version of the line. This arrangement
applied to approximately seven lines that occurred in the overlap area. For
other lines in the overlap area, there was no significant addition to the length
of the western version of the line.

Radar altimeter is believed to have been recorded in feet above ground level.
RADALT has been converted to metres and output into the ASCII located data file.
The original altimeter (feet) has been stored in channel MAGR but not output on
to the ASCII file.

Once a single data base was achieved for the total area. magnetics channel MAG
was microlevelled and stored in MAGL. RADALT and MAGR have been carried through
untouched.

The format of the ASCII file is:
record length 64

Field  Start Character 	Length in	Description
Type	Position	Characters

Line		1	6		Line Number
Fiducial	8	6		Sample Number
*		14	1		Recovered Point Marker
X		16	9		X - AGD66 AMG Zone 55 metres
Y		26	10		Y - agd66 AMG Zone 55 metres
MAG		37	8		Original tie levelled magnetics nTesla
MAGL		46	8		Microlevelled magnetics nTesla
RADALT		55	8		Radar Altimeter metres

This processing has been done by ECS International under the auspices of Mineral
Resources Tasmania. FOr further information contact R. Richardson, MRT,
PO Box 56 Rosny Park, Tasmania, 7018.
Phone 03 62338324
Fax   03 62 338338
E-mail rrichard@mrt.tas.gov.au