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Multinational Andean Project Products Update
MAP CD-ROM
The creation of MAP CD continues apace, with an alpha version anticipated
for the week of July 4. It will comprise a startup screen, skeletal
documentation in HTML format, and an Arc/Info library and Surview (shapefile)
implementation for several themes. Themes that will appear on the alpha
CD are: bedrock geology, metal deposits, geochemisty, geochronology,
paleontology, transportation and drainage. These layers have been compiled
for the purpose of testing and will be replaced with final versions
once editing is complete.
The alpha version is for review purposes only. Over the next three months
more layers will be added, and supporting documentation will be written.
All feedback and suggestions for improvement are welcome. Please contact
Dr. Andrew Makepeace at amakepeace@gsc.nrcan.gc.ca
Metallogenic Map
• All of the latest deposits and edits have been incorporated into
the map for all countries.
• All of the geology edits have been made for all countries, except
a few minor questions.
• Additions to northwest Argentina topography are complete.
• The map will probably need to be reformatted to fit on a smaller
sheet as it is too big for the offset printer. It will be shrunk down
from 65” long to 62.5”, and the title of the map at the top
of the sheet needs to be moved or dropped.
• Legend containing borders, roads, towns, lakes, etc. has been
added.
• Dozens of minor edits were discovered at the meetings in Toronto
and have been corrected.
• Frontispiece has been created according to specifications provided
by Chile.
• Dr. Eduardo Zappettini and Dr. Moyra Gardeweg will be be visiting
Vancouver on the week of June 25th to help with final edits to the map.
Work to be done:
• Arrange printing contract.
• Geology for southeast Peru.
• Geology edits along Peru/Chile border.
• Renumber the deposits from north to south and west to east.
• Generate a series of maps of each bedrock unit for inclusion
in the memoirs.
MAP Sample Database Update
MAPdb is fast approaching completion, and is on track for the final
version being complete and ready for final testing in July or August
2001. Congratulations and thanks are due to all four participating countries
for supplying us with almost all the sample location data that was missing
from the previous version of the database and highlighted at the last
Executive Council Meeting (Toronto). In the last two months there have
been a series of additions resulting from suggestions by the participating
countries and colleagues in Canada. These include the replacement of
questionable Spanish geological terms by ones agreed upon by the Executive
Council, addition of a layout to help users add their own maps to the
map viewer and plotter, addition of detection limits fields for all
chemical components (major and trace elements), and the addition of
a geochronology graphing scheme. The geochronology graph allows users
to inspect graphically the growing number of ages in the database and
has four different age ranges: the entire geological time scale, the
Phanerozoic, the Cenozoic, and the late Quaternary (0 to 100,000 years).
Sample ages are plotted against the percentage error in the age, to
provide a graphical indication of the data quality. Geochronology plots
have the same functionality as the chemical plots in the previous version
of MAPdb, allowing users to search the database graphically and highlight
(identify) individual samples using a cross-hair. A screen capture of
the Cenozoic geochronology plot, with 53 samples plotted, is shown above.
Still to be completed is the addition of a trace element plot and, of
course, the input of all remaining data. If prospective users have any
questions, comments or suggestions for revisions, contact Dr. Mark Stasiuk
at mstasiuk@nrcan.gc.ca as soon as possible.
MAP Samples Update
• No new samples for radiometric dating will be accepted by MAP,
due to the long time required for analytical results to be produced.
• Samples from Peru are to be sent to ALS Chemex Laboratories for
whole rock major and trace element (including rare earth element) analyses,
and thin sections will be made. One batch of 137 samples is ready to
go, and a recently received batch of 42 samples may be approved soon
for geochemical analysis. However, these samples cannot be dated radiometrically
at this time as part of the MAP project.
• Due to the reduced need for a sample coordinator as MAP analytical
activity comes to a close, Dr. Jennifer Getsinger will be leaving MAP
and the GSC at the end of June, after a busy 2-year contract. Remaining
sample data handling and laboratory liaison will be covered by Stasiuk
and Ms. Brenda Marie Brannstrom.
• Mr. Mike Villeneuve (GSC Geochronology Lab, Ottawa) has sent
to Vancouver final reports on some recently analysed MAP radiometric
dating samples, which are being distributed to the countries. For Chile,
the report includes 9 U/Pb zircon dates, with one confirmation from
a U/Pb titanite date; 1 preliminary U/Pb zircon date; 1 unsuitable (no
zircons); and 1 Ar/Ar biotite date. For Argentina, the report includes
1 preliminary U/Pb zircon date, while 7 Ar/Ar dates are still in process.
All radiometric dating work is completed for Bolivia, with final results
reported for 29 Ar/Ar samples, including some that had previously been
put on hold, and later approved for re-analysis.
• The MAP Sample Standards (Geochemical Reference Materials) Project
has been successful in producing three new standards for South America:
a rhyolite from Peru, andesite from Chile, and basalt from Argentina.
Sample bottles are in the process of distribution to the countries.
It was originally intended to create a set of five standards, including
a dacite from Bolivia and basaltic andesite from Chile; however, unforeseen
difficulties have prevented timely collection of suitable sample material
in these countries. Countries are encouraged to continue developing
custom geochemical reference materials on their own when conditions
are more favourable, using the MAP standard set and production process
as a model.
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