ANAM: Programs for Reduction and Quantitative Interpretation of
Magnetic Anomaly data
Program Name |
Function |
emag/emagf |
Calculate COEF matrix to prepare for Magnetization Intensity Mapping.
emagf takes the surface undulation into consideration with the
resolution of terrain data, while emag approximates the source
into blocks with source grid size. Here emagf requires the source
grid size be a multiple of the grid size of terrain data.
|
Parameters: |
log filename input magnetic anomaly data filename (*1)
source altitude data filename source location parameters (*2)
truncation of source effect (km) source bottom configuration (*3)
ambient field direction magnetization direction
COEF matrix output filename
AMAG initial model output filename |
|
amag/amagc |
Execute Magnetization Intensity Mapping, making use of COEF matrix
from emag/emagf process as far as specified loop count or until
converge..
|
Parameters: |
log filename input magnetic anomaly data filename
with removing linear trend or not
COEF matrix input filename AMAG model in/out filename
auxiliary output filename
[amag] number of loops
/ [amagc] convergency torelance (*5)
|
|
cmag/cmagf |
Calculate synthetic magnetic anomaly distribution on the specified
surface caused by the result of Magnetization Intensity Mapping.
cmagf takes the surface undulation into consideration with the
resolution of terrain data, while cmag approximates the source
into blocks with source grid size. Here cmagf requires the source
grid size be a multiple of the grid size of terrain data.
|
Parameters: |
log filename calculation altitude input filename
AMAG model input filename source altitude data filename
truncation of source effect (km) source bottom configuration (*3)
ambient field direction magnetization direction
output data filename |
|
plamag |
Draw contour map of the result of Magnetization Intensity Mapping
on an A4 sheet.
Surrounding source zone is masked, and the range of drawing can be limited.
|
Parameters: |
log filename input AMAG data filename
ref. obs.anomaly data filename
no. of grids [S,N] to limit drawing range
no. of grids [W,E] to limit drawing range
output PS filename paper orientation
contour interval (A/m) size of drawing
supplementary items (scale bar, meridians and parallels,
coastlines etc.) |
|
plamagc |
Draw color-graded contour map of the result of Magnetization Intensity
Mapping on an A4 sheet.
Surrounding source zone is masked, and the range of drawing can be limited.
|
Parameters: |
log filename input AMAG data filename
ref. obs.anomaly data filename
no. of grids [S,N] to limit drawing range
no. of grids [W,E] to limit drawing range
output PS filename paper orientation
color-grading interval (A/m) median value of grading (A/m)
contour-line interval (A/m) size of drawing
supplementary items (scale bar, meridians and parallels,
coastlines etc.) |
|
tmcorr |
Correction of the effect of terrain uniform magnetization
for observed magnetic anomaly GRID data.
|
Parameters: |
log filename observed magnetic anomaly data filename (*1)
with removing linear trend (y) or only DC level (n)
topography data filename truncation distance of source effect (km)
source bottom configuration ambient field direction
magnetization direction terrain corrected output filename
auxiliary output filename |
|
tmcfix |
Correction of fixed terrain magnetization effect
for observed magnetic anomaly GRID data.
|
Parameters: |
log filename observed magnetic anomaly data filename (*1)
topography data filename truncation distance of source effect (km)
source bottom configuration ambient field direction
magnetization direction magnetization intensity
terrain corrected output filename |
|
lcecorr |
Correction of the railway loop-current effect
for observed magnetic anomaly GRID data.
|
Parameters: |
log filename observed magnetic anomaly data filename (*1)
loop location data filename ambient field direction
range of loop-current estimation
LCE corrected output filename auxiliary output filename |
|
aaptdp |
Point-dipole source modeling for observed magnetic anomaly GRID data.
Each time a fitting window is selected, one source model is fitted
automatically, and its effect is removed from the observed magnetic anomaly.
|
Parameters: |
log filename observed magnetic anomaly data filename (*1)
ambient field direction areaname label for model anomaly
model anomaly output filename areaname label for residual data
residual data output filename
how to define window (UTM coordinates / mesh-count)
[repeated until blank line]
data specifying window |
|
galtf |
Interpolate observation altitude of StdLIN data into GRID data.
|
Parameters: |
log filename input StdLIN data filename
effecting radius (km) (new) areaname label
map projection coordinate number (*4) location parameters (*2)
output data filename |
|
galts |
Generate GRID data of smoothed observation altitude from StdLIN data.
|
Parameters: |
log filename input StdLIN data filename
smoothing radius (km) (new) areaname label
map projection coordinate number (*4) location parameters (*2)
output data filename |
|
emeq |
Calculate CMUP matrix to prepare for Altitude Reduction by Equivalent
Anomaly method [Equivalent source surface is defined as a
certain distance below the specified reduction-to surface, and the magnetic
anomaly distribution on the source surface is derived from observed data by
an inversion analysis, then the magnetic anomaly distribution on the
specified surface is calculated as a continuation operation].
|
Parameters: |
log filename input magnetic anomaly data filename (*1)
reduction-to altitude data filename
distance of source surface below the reduction-to surface (m)
truncation of source effect (km) CMUP matrix output filename
AMEQ model initializing output filename |
|
ameq/ameqc |
Execute Altitude Reduction by Equivalent Anomaly method, making use of
CMUP matrix from emeq process as far as specified loop count or
until converge.
|
Parameters: |
log filename input magnetic anomaly data filename
CMUP matrix input filename AMEQ model in/out filename
[ameq] number of loops
/ [ameqc] convergency tolerance (*5)
|
|
cmeq |
Calculate magnetic anomaly distribution on the specified reduction-to
surface, from the Equivalent Anomaly distribution AMEQ derived by
ameq/ameqc process.
|
Parameters: |
log filename reduction-to altitude data filename
AMEQ model input filename truncation of source effect (km)
reduction result data output filename |
|
emeqs |
Calculate CMUPS matrix to prepare for Altitude Reduction by Equivalent
Source Magnetization method [Equivalent source surface is
defined as a certain distance below the specified reduction-to surface, and
the magnetization distribution on the source surface is derived from
observed data by an inversion analysis, then the magnetic anomaly
distribution on the specified surface is forward calculated].
|
Parameters: |
log filename input magnetic anomaly data filename(*1)
reduction-to altitude data filename
distance of source surface below the reduction-to surface (m)
truncation of source effect (km) ambient field direction
magnetization direction CMUPS matrix output filename
AMEQS model initializing output filename |
|
ameqs/ameqsc |
Execute Altitude Reduction by Equivalent Source Magnetization method,
making use of CMUPS matrix from emeqs process as far as specified
loop count or until converge.
|
Parameters: |
log filename input magnetic anomaly data filename
CMUPS matrix input filename AMEQS model in/out filename
[ameqs] number of loops
/ [ameqsc] convergency tolerance (*5)
|
|
cmeqs |
Calculate magnetic anomaly distribution on the specified reduction-to
surface, from the Equivalent Source Magnetization distribution AMEQS
derived by ameqs/ameqsc process.
|
Parameters: |
log filename reduction-to altitude data filename
AMEQS model input filename truncation of source effect (km)
reduction result data output filename |
|
rpmeqs |
Calculate reduction-to-pole magnetic anomaly distribution on the
specified reduction-to surface, translating the Equivalent Source
Magnetization AMEQS derived by ameqs/ameqsc process into vertical,
and also assuming vertical ambient magnetic field direction.
|
Parameters: |
log filename reduction-to altitude data filename
AMEQS model input filename truncation of source effect (km)
calculated reduction-to-pole data output filename |
|
edeq |
Calculate CFUP matrix to prepare for Altitude Reduction from StdLIN line
data by Equivalent Anomaly method [Equivalent source
surface is defined as a certain distance below the specified reduction-to
surface, and the magnetic anomaly distribution on the source surface is
derived from observed StdLIN data by an inversion analysis, then the
magnetic anomaly distribution on the specified surface is calculated as a
continuation operation].
|
Parameters: |
log filename StdLIN line data filename
reduction-to altitude data filename
distance of source surface below the reduction-to surface (m)
truncation of source effect (km) CFUP matrix output filename
ADEQ model initializing output filename |
|
adeq/adeqc |
Execute Altitude Reduction from StdLIN line data by Equivalent Anomaly
method, making use of CFUP matrix from edeq process as far as
specified loop count or until converge.
|
Parameters: |
log filename StdLIN line data filename
CFUP matrix input filename ADEQ model in/out filename
[adeq] number of loops
/ [adeqc] convergency tolerance (*5)
|
|
cdeq |
Calculate magnetic anomaly distribution on the specified reduction-to
surface, from the Equivalent Anomaly distribution ADEQ derived by
adeq/adeqc process.
|
Parameters: |
log filename reduction-to altitude data filename
ADEQ model input filename truncation of source effect (km)
reduction result data output filename |
|
edeqs |
Calculate CFUPS matrix to prepare for Altitude Reduction from StdLIN line
data by Equivalent Source Magnetization method [Equivalent
source surface is defined as a certain distance below the specified
reduction-to surface, and the magnetization distribution on the source
surface is derived from observed StdLIN data by an inversion analysis, then
the magnetic anomaly distribution on the specified surface is forward
calculated].
|
Parameters: |
log filename StdLIN line data filename
reduction-to altitude data filename
distance of source surface below the reduction-to surface (m)
truncation of source effect (km) ambient field direction
magnetization direction CFUPS matrix output filename
ADEQS model initializing output filename |
|
adeqs/adeqsc |
Execute Altitude Reduction from StdLIN line data by Equivalent Source
Magnetization method, making use of CFUPS matrix from edeqs process
as far as specified loop count or until converge.
|
Parameters: |
log filename StdLIN line data filename
CFUPS matrix input filename ADEQS model in/out filename
[adeqs] number of loops
/ [adeqsc] convergency tolerance (*5)
|
|
cdeqs |
Calculate magnetic anomaly distribution on the specified reduction-to
surface, from the Equivalent Source Magnetization distribution ADEQS
derived by adeqs/adeqsc process.
|
Parameters: |
log filename reduction-to altitude data filename
ADEQS model input filename truncation of source effect (km)
reduction result data output filename |
|
rpdeqs |
Calculate reduction-to-pole magnetic anomaly distribution on the
specified reduction-to surface, translating the Equivalent Source
Magnetization ADEQS derived by adeqs/adeqsc process into vertical,
and also assuming vertical ambient magnetic field direction.
|
Parameters: |
log filename reduction-to altitude data filename
ADEQS model input filename truncation of source effect (km)
calculated reduction-to-pole data output filename |
|
calmas |
Calculate theoretical magnetic anomaly distribution on the
specified observation surface, caused by a symple source model (rectangular
block, horizontal rectangle with infinitesimal thickness, vertical line
segment with infinitesimal thickness, point with infinitesimal volume or
any combination of them).
|
Parameters: |
log filename observation altitude data filename
calculated result output filename
how to specify position (0: Coord. values / 1: Distance from SW
corner) ambient field direction
[may be repeated]
Model type (1:Block, 2:hRect, 3:vLine, 4:Point)
Northing (km) (Median and NS size for Block/hRect)
Easting (km) (Median and EW size for Block/hRect)
Depth (km) (Top and bottom for Block/vLine)
[for other than Block]
effective thickness/sectional area/volume
Magnetization (A/m)
magnetization direction
[at the end] 0 [: Model type] |
|
(*1) |
If observation altitude of input GRID data is undefined,
additional altitude data input will be required. |
(*2) |
"location parameters" include Northing and Easting of Southwest
corner, mesh interval and number of mesh to the North, and to the East.
|
(*3) |
"source bottom configuration" is selected from Flat Bottom or
Constant Thickness model, with specification of its depth or thickness.
|
(*4) |
If the map projection is not UTM, information of the origin will
be required. |
(*5) |
The process is finalized if the percentage of improvement in RMS
mismatch is less than the specified value (default: 2%) for 5 continuous
iterations, or if the RMS misfit becomes less than 0.1 nT. |
Standard Format of GRID data file v2005
1. One file consists of 1 set of GRID data, or multiple sets of GRID data.
The 2nd set or further behind of multiple sets of GRID data is restricted
in usage, and is valid only for cases below.
(1) 1st set GRID data indicates a distribution of any physical quantity
on a curved surface, and the altitude distribution of the surface is
given by 2nd set GRID data.
(2) The file consists of a series of independent GRID data, and they are
not used for other than illustrating each distribution.
2. The unit for the physical quantity (grid data) is, in principle,
nT for magnetic field, m for altitude, 0.01 A/m for magnetization, mGal
for gravity, or others as derived from them. And it is recommended to use
the value of positive 99999 in effective digits for representing null
value (the lack of valid data).
3. Every data line in GRID data file may not exceed 80 bytes excluding LF
code. And it is recommended to be 79 bytes or less excluding LF.
4. Data in GRID data file may not include multi-byte characters, and
control codes other than LF shall not be used.
Each set of GRID data is constructed as follows.
a) Comment: Before 1st Header, arbitrary lines of comment can be placed.
Comment line has "#" on the 1st column and is 80 byte long at most.
b) 1st Header (Areaname and information of map projection) [fixed format]
FORMAT(a8, i4,4x, 2i8, 2i8)
area: 8 byte string representing Areaname or else, not starting with "#".
nc: coordinate number of map projection (usually UTM zone number)
0 : Japanese transverse Mercator coordinates
1-60 : UTM coordinates zone number
61 : North pole UPS coordinates
62 : South pole UPS coordinates
65 : UTM coordinates with non-standard central meridian
70 : Mercator projection
71 : Lambert conformal conic projection (1 standard parallel)
72 : Lambert conformal conic projection (2 standard parallels)
100 : Lambert Azimuthal Equal-Area Projection
(from the sphere with surface area equal to the earth)
109 : Lambert Azimuthal Equal-Area Projection
(from the sphere with equatorial radius equal to the earth)
199 : Latitude/Longitude in minutes are regarded as distance in km
These numbers above are for the Bessel ellipsoid (Tokyo datum).
For GRS ellipsoid (WGS-ITRF), add 200 to the corresponding projection.
ig, kg : Latitude and Longitude (in minutes) of origin
[neglected for nc = 1 to 62]
i1, i2 : Latitudes (in minutes) of standard parallels
[valid only when nc = 72]
In general, coordinate values are X (Northing) = Y (Easting) = 0 at the
origin. However, in UTM (nc = 1 to 60, or 65) X = 0, Y = 500,000 (m), and
in UPS (nc = 61 or 62) X = Y = 2,000,000 (m), at the origin.
c) 2nd Header (Grid information, null value and altitude) [free format]
FORMAT(2i12, 2i6, 2i6, 1x,f7.1, 1x,f7.0) (as standard)
ixs, iys : Northing and Easting (in m) of Southwest corner of GRID [integer]
mszx,mszy: mesh size (in m) towards North and East [integer]
mxn, myn : mesh count (including both ends) towards North and East [integer]
vnul : special value representing the lack of valid data [real]
alt : observation altitude (in m) [real]
(If the value = 0., the distribution of observation surface is
given as 2nd set GRID data, and if negative (-1.), the altitude
of observation is undefined. For the 2nd set GRID data (i.e.,
altitude data) this is filled with -1., though meaningless.)
d) GRID data body [free format]
FORMAT((f7.1, 9(1xd,f7.1))) (as standard)
All grid data are listed out in the order that starts from Southwest corner
toward North, and on arriving North end proceeds to next East row.
Next expression is the equivalent FORTRAN statement reading this data.
read(10,*) ((f(i,k),i=1,mxn),k=1,myn)
However, for the output programming, line break operation between rows
do 1 k=1,myn
write(10,'((f7.1,9(1x,f7.1)))') (f(i,k),i=1,mxn)
1 continue
is recommended.
StdLIN line data Format (example)
# Areaname: Kobe-Kyoto
# Survey Date: 1995.12.07-12.27
&A-01
2079.0222N 8116.2764E 277.8m -45.1nT
2079.0405N 8116.3164E 278.5m -44.6nT
2079.0588N 8116.3564E 279.1m -44.4nT
.......
2087.3958N 8134.2559E 275.4m -48.3nT
2087.4158N 8134.2964E 275.4m -53.6nT
& C-2r
2088.2712N 8134.3799E 279.1m -44.9nT
2088.2563N 8134.3384E 279.3m -40.8nT
2088.2407N 8134.2964E 279.6m -40.1nT
.......
Lines starting with '#' are comment information, usually placed only at
the head of the file. (Never be placed among series of line data.)
Lines starting with '&' or '%' indicate the start of line data.
Line name (number) is described in 2nd-9th columns, and the form of
the rest is not restricted. (Starting time and number of data points
included are commonly described.)
In some cases, a line with no data points is defined for explicit
declaration of the end of file.
All other lines are data of individual points, consisting of Latitude
(in minutes), Longitude (in minutes), Altitude (in m), and Residual
magnetic anomaly (in nT) data, with the format (42 columns) of
format(f10.4, 1hN, f11.4, 1hE, f8.1, 1hm, f8.1, 2hnT).