Visualisation of Geological Observations on Web 2.0 Based Maps - Maps for the Future Children Education and Internet - page 170

Language) files were created for data exchange purposes. The following section
gives a detailed description of the re-shaped document structure, which can be
considered as fields or collections (queries) of the final database.
14.2.1 Database of the Geological Observations
The geologist, who is responsible for the documentation, uses numbers and letters
to create a code for each registered outcrop during mapping. It is the way of
documentation now and it was the same a hundred years ago. During these many
years, the codes naturally change and one code may often occur repeatedly, thus in
creating the new database it was a primary requirement to work out a unique and
easily understandable naming method for the database entries.
The mapping is carried out at large scale (1:10,000) state topographic maps. The
projection of these maps is the official Hungarian National Grid (EOV) system, but
the coordinates can be recorded or transformed into latitudes and longitudes on
standard WGS84 datum.
The database is represented by several main, sub- and code tables (Fig. 14.4 ).
The main tables contain genuine data, like the observation points themselves, or the
maps of the region concerned. Sub-tables contain details of the observations, like
the measurements and photos taken, or the samples and fossils collected. The code
tables store the repeatedly occurring data, such as the objects measured (e.g. fault
plane), the names of the fossils, and the observers.
Each record in the “observations” main data table is identified by a unique key in
the “op_id” field, which links this table with other sub-tables in the database. It was
considered that the database would be better understandable for the geologists, if
the unique identifiers are designed to contain real names and numbers. These kinds
of identifiers are called natural keys. To produce a natural key field, a 4-letter code
of the documented area was put together with the monogram of the documenter and
the number of the observation point (e.g.: LAB3-AG051 is the natural key for the
51st site of G´sp´r Albert on the map, which is coded as LAB3). The area codes are
also natural keys, since they are abbreviations of the name of the topographic maps.
For example, the code LAB3 is the third sub-sheet of the map called “L´batlan”,
named after a little village in the area.
The rules of the documentation are strict. From the formatting of the identifica-
tion numbers to the applicable characters in the string data of the geological
descriptions, are all strictly defined. Without the restricting VBA (Visual Basic
Applications) codes, hardly a few documenters would keep themselves to the
formalities. These codes (macros) are built in the model Word document, and
they also handle the link to the database.
The field documentation is slightly different, since these codes are not compati-
ble with the mobile applications of the data recording device. Thus the data, which
were recorded in the field, go through a syntax-controller program before the
processing.