Main maps

1. Base map
The topographical base and the presented area of the map will be identical with the Carpatho-Balkan-Dinaride map (Szádeczky-Kardoss et al., 1976). We already have the permission to storage the old map in digital form from the copyright holder.

2. Naming conventions
Local transcription (in case of Cyrillic and Greek names and special characters not available in English transcription).

3. Layers for orientation
Geographic grid
         One-degree latitude and longitude grid.
         Coastlines, lakes and rivers.
         Settlements (> 100,000) and state boundaries.

4. Geological content
4.1. Subdivision
The Main maps are composed of Units (see below). The Units are separated by Boundaries. The subdivision created for "Map of Alpine metamorphism" is used also for the "Map of Variscan and pre-Variscan metamorphism".

4.2. Data reliability
The content of the Main maps (both the Boundaries and the Units) are considered and presented in three reliability levels:
         —Interpreted, supposed,
         —Unknown (indicated by question-marks and by gray colour).

4.3. Generalisation
        The suggested minimum size of distinct objects are 2 to 3 mm on the Main maps. That refers to geological objects of 2 to 3 km in real size.
        — Complicated Boundaries and spotted occurrences of a Unit need simplification.
        — Occurrences of Units with small size (lamellae, remnants of nappes) require enlargement to the suggested minimum size.

4.4. Categories according to the age of metamorphism
        The time scale of Harland et al., 1989 is considered.
        Horizontal stripes: uncertanity or results of two age groups.
        Vertical stripes: two distinct and identified metamorphic phases.
4.4.1. Map of Alpine metamorphism
        — Early-Middle Jurassic ages (from 210 to 160 Ma mica or amphibole K/Ar or Rb/Sr cooling or formation ages),
        — Late Jurassic-Early Cretaceous (ages between 160 and 110 Ma),
        — Late Cretaceous (ages between 110 and 65 Ma),
        — Tertiary (ages < 65 Ma),
        — No Alpine metamorphism,
        — Supposed (no borerhole reached metamorphic formations, but the given area is evidently a part of a unit),
        — Unknown (usually below thick unmetamorphosed cover).

        Point-like symbols
        — If a Unit contains scattered geochronological results which are considerably younger/older than the characteristic metamorphic age of the Unit, these individual data points (or a generalised cluster of them) can be placed on the map (see Legend). Such a scenario is not uncommon, for example Tertiary ages occur (mainly along shear zones) in many areas dominated by Cretaceous metamorphism.

4.4.2. Map of pre-Alpine metamorphism
        — Pre-Variscan ( > ca. 400 Ma),
        — Variscan 400-300 Ma,
        — Permo-Triassic (ages between 300 and 210 Ma),
        — No Pre-Alpine metamorphism,
        — Unknown (below thick sedimentary cover or overprinted by high grade Alpine metamorphism).

4.5. Categories according to metamorphic grade (within the age categories)
        Areal symbols
        — Subgreenschist facies metamorphism,
        — Greenschist facies metamorphism,
        — Amphibolite facies metamorphism (lower-upper, where the Authors make distinction),
        — Blueschist facies metamorphism.
        Point-like symbols
        — Occurrence of eclogite facies metamorphism,
        — Occurrence of granulite facies metamorphism.