IGCP Board; 10th session; Report of the ... - unesdoc - Unesco

interest in geohistory analysis. The prerequisite
to this approach is a good calibration of sections
to the geochronologic scale. Several participants
of the Project are interested in automatic
image analysis for the study of morphology.
Recently, Zhang Yun and H.J, Hofmann
have obtained promising results by image analysis
of lamina profiles of Precambrian stromatolite
taxa.
Activities planned. Five participants in the Project
will conduct a short course on "New Concepts
and Methods in Stratigraphy" on 21-25
June, 1982, in Calgary, Canada, immediately
preceding the Annual Convention of the American
Association of Petroleum Geologists. The
international meeting for 1982 will take place on
22-23 November at the University of Geneva in
Switzerland. Its theme will be "Theory, application
and comparison of stratigraphical correlation
methods". A final meeting before completion
of the Project is planned for December
198 3 in India.
No. 154 GLOBAL EXCHANGE AND PROCES­
SING OF INFORMATION IN GEOCHEMISTRY
H. de la Roche, BRGM, B.P. 6009, 45060
Orléans; J. M. Stussi, CRPG, B.P. 20;
54501 Vandoeuvre-les-Nancy, France.
Description. The main topics of the Project
are: (1) to identify, in the framework of a defined
scientific project, the problems encountered
in exchanges of geochemical and additional data
(location, geology, petrography); (2) to appraise
the opportunity and possibility of defining
standards for communication and automatic processing
of these data. This experiment is conducted
through a scientific programme of "Comparative
geochemistry of two-mica granites and
associated rocks from various orogens".
The Project aims at the following results: (1) in
applied sciences and technology: identification
of the problems encountered in data exchanges
between existing geochemical files and data
banks, and research for solutions (from logistic,
technical, economic, and psychological
points of view); setting up a network of geochemical
data banks; (2) in theoretical sciences:
geochemical and metallogenic characteristics of
two-mica granites and associated rocks in relation
with their typology and location in an orogen,
in order to appraise the notion of geochemical
provinces; interregional and intercontinental
geochemical correlations.
Summary of activities. The activities of the
Project have been focused essentially on bilateral
contacts between centres expecting interesting
developments in this field. A retrospective
file of geochemical and additional data of the
granites in northern Portugal has been computerized
and at present is operative. The generation
of a Spanish data bank and the development
46
of the thematic files in Bulgaria have aroused a
renewal of interest in the Project. Hence, interesting
perspectives of exchanges and processing
can be expected. With regards to the French
Hercynian, the stage correlations between isopic
segments of the orogen are reached mainly with
the graphical presentation of the chemical typology
of the granites. The chemical data are identified
as pertinent markers for correlation and
make it possible to avoid the difficulties encountered
by the usually empiric and regional petrographical
designations.
The existence of the computerized and published
data of the granites in Central Europe gives, at
present, the possibility with the French and Portuguese
operative files, of exchanges and processing
of data which have derived from three major
regional units of the same European Hercynian.
The typological map of the French granites is,
in this respect, an important achievement and
the interorogenic data exchanges are being developed
with Australia.
Activities planned. The Project so far has worked
on the geotechnical data of two-mica granites
and associated rocks. It will extend its investigation
to all types of granites and, moreover,
also to metallogenic, structural, and isotopic
data thereof which are pertinent to the refinement
of the different types of intra- and interorogenic
correlations. From the point of view of computerization,
the integration of such data in existing,
operative data banks requires the creation of an
information system for efficient and rational usage.
At the meeting scheduled for 1982 in Orléans,
France, a tentative discussion will be arranged
for the elaboration of information and communication
standards liable to fulfil this objective.
No. 156 PHOSPHORITES
P.J. Cook, Research School of Earth Sciences,
Australian National University, P.O. Box 4,
Canberra ACT 2600, Australia.
J.H. Shergold, Bureau of Mineral Resources,
P.O. Box 378, Canberra ACT 2601, Australia.
Description. Project 156 is a multidisciplinary
research programme to investigate the nature
and distribution of sedimentary phosphate deposits.
The study provides a clearer understanding of
the processes relating to the genesis of recent
and ancient phosphorites as well as useful palaeogeographic,
palaeo-oceanographic and stratigraphie
information. It also provides a better
understanding of the relationship between phosphorites
and other forms of mineralization, and
phosphorites and petroleum-source rocks. It
assiste in the development of an international
phosphate resource data base and a code of nomenclature.
It contributes to the search for
this important food mineral, both through the
development of new ideas, and by providing geologists
(especially those in developing countries)
with the opportunity to familiarize themselves
with phosphate deposits in other countries.