Entity_and_Attribute_Overview:
Airborne survey specifications
These items are constant for the entire survey
Project number: 5020
Project name: Chelan, Washington
Survey flown by: LKB Resources, Inc. and Carson Helicopters
Survey flown for: DOE Grand Junction Office
Approx. no. of line miles: 238
Survey height: 400 ft
Altitude method: Draped over terrain
Flight-line spacing: 0.5 mi
Flight-line direction: East-West
Aircraft used: Sikorsky S58T
Airport - arrival: unknown
Airport - departure: unknown
Magnetometer used: ASQ-10 fluxgate
Magnetometer location: mounted on side of helicopter
Radiometric crystal package volume: 2154 (down) & 318 (up) cu. in.
Entity_and_Attribute_Detail_Citation:
Nettleton, L.L., 1971, Elementary Gravity and Magnetics for
Geologists and Seismologists: Society of Exploration Geophysicists
Monograph Series No. 1, p. 83-87.
Dobrin, M.B., 1976, Introduction to Geophysical
Prospecting: New York, McGraw-Hill Book Company,
p. 505-517.
Grasty, R.L., and Holman, P.B., 1974, Optimum Detector Sizes for
Airborne Gamma-ray Surveys: Geological Survey of Canada Paper
74-1, Part B, p. 72-74.
Entity_and_Attribute_Overview:
Aeromagnetics
Each record contains the following 12 attributes:
No name contents
1 line flight line number
2 fid fiducial number (integer)
3 time time (hhmmss)
4 day Julian day flown (integer)
5 year year flown (integer)
6 latitude latitude (decimal degrees)
7 longitude longitude (decimal degrees)
8 radalt radar altimeter reading above ground (meters)
9 totmag corrected magnetic value (nT)
10 resmag residual magnetic value (nT)
11 diurnal ground magnetometer value (nT)
12 geology surficial geology beneath flight line (coded)
Entity_and_Attribute_Overview:
Radiometrics
Each record contains the following 21 attributes:
No name contents
1 line flight line number
2 fid fiducial number (integer)
3 time time (hhmmss)
4 day Julian day flown (integer)
5 year year flown (integer)
6 latitude latitude (decimal degrees)
7 longitude longitude (decimal degrees)
8 radalt radar altimeter reading above ground (meters)
9 resmag residual magnetic value (nT)
10 geology surficial geology beneath flight line (coded)
11 qual quality flags of the radiometrics (integer)
12 app_K apparent Potassium as Potassium 40 (percent potassium)
13 app_U apparent Uranium as Bismuth 214 (parts per million
equivalent uranium)
14 app_Th apparent Thorium as Thallium 208 (parts per million
equivalent thorium)
15 U_Th_ratio ratio of Uranium and Thorium
16 U_K_ratio ratio of Uranium and Potassium
17 Th_K_ratio ratio of Thorium and Potassium
18 total_count total count of radioactivity (counts/second)
19 atmos_BI214 atmospheric Uranium as Bi214 (counts/second)
20 air_temp air temperature (degrees Celsius)
21 air_press air pressure (mmHg)
Entity_and_Attribute_Detail_Citation:
Nettleton, L.L., 1971, Elementary Gravity and Magnetics for
Geologists and Seismologists: Society of Exploration Geophysicists
Monograph Series No. 1, p. 83-87.
Dobrin, M.B., 1976, Introduction to Geophysical
Prospecting: New York, McGraw-Hill Book Company,
p. 505-517.
Parasnis, D.S., 1975, Mining Geophysics: Elsevier Scientific
Publishing Company, Methods in Geochemistry and Geophysics vol. 3,
p. 298-307.
- record for one magnetic or radiometric data point
- The set of all measurements reported for a magnetic or radiometric
data point having the same spatial location.
(Source: Standard aeromagnetic and aeroradiometric data collection procedures as written in the contract for survey collection.)
- line
- flight line number
(Source: often assigned by airborne survey crew)
| Range of values |
|---|
| Minimum: | 1 |
|---|
| Maximum: | 102 |
|---|
| Units: | alphanumeric value |
|---|
- fid
- A fiducial number is a mark which indicates points of
simultaneity. It is a user-defined integer used during
airborne operations to correlate recording devices (magnetometers)
with navigational records (altimeters, camera film, strip charts)
that were recorded at the same time.
(Source: Sheriff, R.E., 1984, Encyclopedic dictionary of exploration geophysics: Tulsa, OK, Society of Exploration Geophysicists, p. 89.)
| Range of values |
|---|
| Minimum: | 37180 |
|---|
| Maximum: | 58342 |
|---|
- time
- time of data point collection. Time is given
in either local time or Greenwich Meridian Time.
Values of 999999 indicate missing data.
(Source: self evident)
a range of time of day values has no meaning
because the timeframe can span several days or weeks.
- day
- Julian day, where Jan. 1 = 1 and
Dec. 31 = 365 or 366 (leap year)
(Source: self evident)
| Range of values |
|---|
| Minimum: | 255 |
|---|
| Maximum: | 255 |
|---|
- year
- year of data point collection
(Source: self evident)
| Range of values |
|---|
| Minimum: | 1979 |
|---|
| Maximum: | 1979 |
|---|
- latitude
- latitude - geographic coordinate
(Source: self evident)
| Range of values |
|---|
| Minimum: | 47.7494 |
|---|
| Maximum: | 48.0001 |
|---|
| Units: | decimal degrees |
|---|
- longitude
- longitude - geographic coordinate
(Source: self evident)
| Range of values |
|---|
| Minimum: | -120.0222 |
|---|
| Maximum: | -119.8574 |
|---|
| Units: | decimal degrees |
|---|
- radalt
- radar altimetry reading, in meters
An aircraft navigational system in which short electromagnetic waves
are transmitted, and the energy scattered back by reflection
is detected. From this measurement, the distance between the aircraft
and the ground is calculated and recorded as radar altimetry.
Values of -999.9 indicate missing data.
(Source: Sheriff, R.E., 1984, Encyclopedic dictionary of exploration geophysics: Tulsa, OK, Society of Exploration Geophysicists, p. 89.)
| Range of values |
|---|
| Minimum: | 57.6 |
|---|
| Maximum: | 462.1 |
|---|
| Units: | meters |
|---|
- totmag
- Raw magnetic value with base magnetometer corrections applied.
Because the magnetic field of the earth varies diurnally,
a stationary base magnetometer is maintained on the ground
during airborne surveying. The base magnetometer records
changes in the magnetic field (in nanoTeslas) as a function
of time. The magnetic changes may have an amplitude of 20
to 50 nanoTeslas. If changes are more severe, as would
occur from a magnetic storm, surveying is discontinued or
the data recorded are not used.
Diurnal variations are then removed from the airborne magnetic
data based on the common time.
Records containing missing data were usually deleted.
(Source: see: Nettleton, L.L., 1971, Elementary Gravity and Magnetics for Geologists and Seismologists: Society of Exploration Geophysicists Monograph Series No. 1, p. 83-87. A description of magnetometers and how they measure the total magnetic field can be found in: Dobrin, M.B., 1976, Introduction to Geophysical Prospecting: New York, McGraw-Hill Book Company, p. 505-517.)Frequency of measurement: The magnetometer has a recharging interval of 0.5 seconds. The data were recorded at 1 second intervals.
| Range of values |
|---|
| Minimum: | 53836.4 |
|---|
| Maximum: | 55018.6 |
|---|
| Units: | nanoTeslas |
|---|
- resmag
- residual magnetic value
The total magnetic value minus a geomagnetic reference field (GRF),
which is a long-wavelength regional magnetic field. The most commonly
used reference field is determined from a model developed by the
International Association of Geomagnetism and Aeronomy (IAGA). The
International Geomagnetic Reference Field (IGRF), is a predictive model
adopted at the beginning of a model period (e.g. in 1989 for 1990-1995).
After the model period, a revised definitive model is adopted, the DGRF.
This is the preferred model to use for removing regional magnetic fields.
For this survey, the field removed is IGRF 1975.
Some contractors add a constant to the residual value in order to
avoid negative values. This constant can vary from one data set to
another.
Values of -9999.9 indicate missing data.
(Source: Nettleton, L.L., 1971, Elementary Gravity and Magnetics for Geologists and Seismologists: Society of Exploration Geophysicists Monograph Series No. 1, p. 83-87.)
| Range of values |
|---|
| Minimum: | 53954.40 |
|---|
| Maximum: | 55039.10 |
|---|
| Units: | nanoTeslas |
|---|
- diurnal
- Base magnetometer values used to correct the total magnetic
value.
Because the magnetic field of the earth varies diurnally,
a stationary base magnetometer is maintained on the ground
during airborne surveying. The base magnetometer records
changes in the magnetic field (in nanoTeslas) as a function
of time called the diurnal. The magnetic changes may have an
amplitude of 20 to 50 nanoTeslas. The diurnal is monitored
during the survey and if changes are severe, as would
occur from a magnetic storm, surveying is discontinued or
the data recorded are not used.
Diurnal variations are then removed from the airborne magnetic
data based on the common time.
Values of -9999.9 indicate missing data.
(Source: see: Nettleton, L.L., 1971, Elementary Gravity and Magnetics for Geologists and Seismologists: Society of Exploration Geophysicists Monograph Series No. 1, p. 83-87. A description of magnetometers and how they measure the total magnetic field can be found in: Dobrin, M.B., 1976, Introduction to Geophysical Prospecting: New York, McGraw-Hill Book Company, p. 505-517.)Frequency of measurement: The base magnetometer has a recharging interval of 0.5 seconds. The data were recorded at 2-4 second intervals.
| Range of values |
|---|
| Minimum: | 50780.2 |
|---|
| Maximum: | 50845.0 |
|---|
| Units: | nanoTeslas |
|---|
- geology
- Geologic identification codes or numeric codes indicating the rock
types immediately beneath the flight line. These codes were determined by
plotting the flight lines on a surficial geologic map. A description
of the codes can be found in the GJBX- or GJO- report for this
quadrangle listed in the Cross Reference section above.
Values of -99 indicate missing data.
(Source: original publication)
values are not quantified
- apparent potassium
- the apparent content of potassium in the surface
rock and soil
Values of -99.9 indicate missing data.
(Source: Duval, J. S., 1990, Modern aerial gamma-ray spectrometry and regional potassium map of the conterminous United States: Journal of Geochemical Exploration, vol. 39, no. 1-2, p. 249-253.)Frequency of measurement: The data were recorded at 1-2 second intervals.
| Range of values |
|---|
| Minimum: | -0.5 |
|---|
| Maximum: | 5.0 |
|---|
| Units: | percent potassium |
|---|
- apparent uranium
- the apparent content of uranium in the surface
rock and soil
Values of -99.9 indicate missing data.
(Source: Duval, J. S., 1990, Modern aerial gamma-ray spectrometry and regional potassium map of the conterminous United States: Journal of Geochemical Exploration, vol. 39, no. 1-2, p. 249-253.)Frequency of measurement: The data were recorded at 1-2 second intervals.
| Range of values |
|---|
| Minimum: | -2.6 |
|---|
| Maximum: | 8.9 |
|---|
| Units: | parts per million equivalent uranium (ppm eU) |
|---|
- apparent thorium
- the apparent content of thorium in the surface
rock and soil
Values of -99.9 indicate missing data.
(Source: Duval, J. S., 1990, Modern aerial gamma-ray spectrometry and regional potassium map of the conterminous United States: Journal of Geochemical Exploration, vol. 39, no. 1-2, p. 249-253.)Frequency of measurement: The data were recorded at 1-2 second intervals.
| Range of values |
|---|
| Minimum: | -2.7 |
|---|
| Maximum: | 12.6 |
|---|
| Units: | parts per million equivalent thorium (ppm eTh) |
|---|
- total count
- the gross effect of the content of uranium, thorium,
and potassium in the surface rock and soil
Values of -9999.9 indicate missing data.
(Source: Pitkin, James A., 1968, Airborne measurements of terrestrial radioactivity as an aid to geologic mapping: U.S. Geological Survey Professional Paper 516-F, 29 p.)Frequency of measurement: The data were recorded at 1-2 second intervals.
| Range of values |
|---|
| Minimum: | 13.0 |
|---|
| Maximum: | 2248.0 |
|---|
| Units: | counts per second |
|---|
- atmospheric bismuth 214
- the atmospheric content of equivalent uranium
determined by measuring the amount of its decay product bismuth 214.
Values of -99.9 indicate missing data.
(Source: Duval, J. S., 1990, Modern aerial gamma-ray spectrometry and regional potassium map of the conterminous United States: Journal of Geochemical Exploration, vol. 39, no. 1-2, p. 249-253.)Frequency of measurement: The data were recorded at 1-2 second intervals.
| Range of values |
|---|
| Minimum: | 0.0 |
|---|
| Maximum: | 0.1 |
|---|
| Units: | parts per million |
|---|
- air temperature
- temperature of the air in degrees Celsius
Values of -999.9 indicate missing data.
(Source: self evident)
| Range of values |
|---|
| Minimum: | 18.3 |
|---|
| Maximum: | 29.6 |
|---|
- air pressure
- pressure of the air measured in millimeters
of mercury (mmHg)
Values of -999.9 indicate missing data.
(Source: self evident)
| Range of values |
|---|
| Minimum: | 642.0 |
|---|
| Maximum: | 726.8 |
|---|
- qual
- quality flags indicating the relative quality
of the radiometric data. A description of the codes can be found
in the GJBX- or GJO- report for this quadrangle listed in the
Cross Reference section above.
Values of -9999 indicate missing data.
(Source: original publication)
values are not quantified
- U-Th ratio, U_K ratio, and Th_K ratio
- The calculated ratios of uranium, thorium, and
potassium.
Values of -99.9 indicate missing data.
(Source: self evident)
ranges of values were not determined
