Software created for the Paleomagnetism Laboratory - IAG/USP
NOTICE: all the programs here available for download are more or
less experimental and may contain errors. Always use them with caution,
and contact me if you find any
problem.
Susceptibility, Magnetization and Anisotropy
Beeing inter-related measurements, the basic strategy is to keep all information
on a single file (s.f.), in text format for easier editing (e.g.: EXAMPLE.ALL
- the .ALL extension is not mandatory). Thhe s.f. is hierarchically organized
like a book index, and is unique for each sample collection. To handle
this s.f. :
-
The program ENTRAR.EXE (Quickbasic/DOS source:
ENTER.BAS) is a sort of dedicated editor, that creates the initial "skeleton"
of a new collection, inserting details about sampled sites, cylinders/blocks
and prepared samples, besides calculating the field corrections from the
solar and magnetic compasses readings. Optionally, it can be used to add
data to an already created collection or to "enter" measurements manually.
Usage: ENTRAR data-file.
-
The program LISTAR.EXE (Quickbasic/DOS source:
LISTAR.BAS) extracts selected information from the s.f. and sends it to
an output file (or the printer alias, PRN). Usage: LISTAR output-file
options data-file.
-
The program ARQUIVAR.EXE (TurboPascal/DOS source:
ARQUIVAR.PAS) imports to the s.f. all the measurements of susceptibility,
magnetization and anisotropy (s.m.a.) obtained in one of the preexistent
laboratory data formats (OBS.: for pos-s.f. measurement software this stage
is unnecessary, because results are send directly to the s.f.) Usage: ARQUIVAR
measurement-files data-file.
Unfortunately, the s.m.a. measuring programs cannot be available here.
Those that are not proprietary (i.e., came with the equipment) need modifications
in the hardware to work properly (ex. : MINISEP
system), making then unusable for non-customized equipment. So analysis
software comes next.
Magnetization analysis:
-
The program ANALISAR.EXE (Quickbasic/DOS source:
ANALISAR.BAS) interactively allows to determination of those vetorial components
isolated during a series of demagnetizations, and records them in the s.f..
Uses principal component analysis. Usage: ANALISAR data-file.
-
The program MEDIADIR.EXE (Quickbasic/DOS source:
MEDIADIR.BAS) interactively computes the site mean of those components
(directions) generated by the program ANALISAR, also recording them in
the s.f.. Usage: MEDIADIR data-file.
-
The program MEDIAPOL.EXE (Quickbasic/DOS source:
MEDIAPOL.BAS) interactively averages the virtual geomagnetic poles (VPGs)
associated with those site means generated by the program MEDIADIR. Usage:
MEDIAPOL
data-file.
Anisotropy analysis:
-
The program MED-ANI.EXE (Quickbasic/DOS source:
MED-ANI.BAS) interactively computes site means from a set of measured anisotropies.
Usage: MED-ANI data-file.
Rock Magnetism
The strategy here is not exactly as described above: the files are still
in text format, but are different for each equipment. The differentiation
occurs by file extension (e.g.: EXAMPLE.BAR
for the Bartington susceptibility vs. temperature system and EXAMPLE.VSM
for the Molspin vibrating sample magnetometer).
For the Bartington susceptibility vs. temperature MS2 & MS2WFP system:
-
The program BART.EXE (Quickbasic/DOS source: BART.BAS)
coordinates the recording of thermomagnetic curves. Usage: BART
(and follow the instructions, step by step).
-
The program ANA-BART.EXE (Quickbasic/DOS source:
ANA-BART.BAS) allows the determination of all Curie points from the curves
obtained, using the (experimental) approach of the maximum of curvature.
Usage: ANA-BART data-file[.BAR].
For the Molspin vibrating sample magnetometer (VSM-NUVO):
-
The program MEDE-VSM.EXE (Quickbasic/DOS source:
MEDE-VSM.BAS) controls the attainment of remanescence and/or hysteresis
curves. The initial configurations come in the VSM.INI (text) file, for
easy edition. To subtract the effect of the sample holders, just measure
them in advance as: PA1, PA2 etc in the .VSM file whose name is informed
inside VSM.INI. Usage: MEDE-VSM (and follow the instructions, step
by step).
-
The program ANA-VSM.EXE (Quickbasic/DOS source:
ANA-VSM.BAS) allows the determination of the susceptibility, hysteresis
and remanescence parameters for (the saturated fraction of) those curves
present in a .VSM file, recording them in the same file. Usage: ANA-VSM
data-file[.VSM].
-
The program DAY-VSM.EXE (Quickbasic/DOS source:
DAY-VSM.BAS) plots the Day diagram (Mrs/Ms vs. Hcr/Hc) for those parameters
just recorded by the program ANA-VSM. Usage: DAY-VSM data-file[.VSM].