FAQs - Frequently Asked Questions

— Why the Main maps do not show the thickness isolinies of the covering non-metamorphic sequences?
It is planned in a later phase.

— Why the Main maps do not show the lithology?
(i) The lithology is available already on several maps (on large scale: Machel' et al., 1973 and Szádeczky-Kardoss et al., 1976 and on numerous small scale geological maps published by the national geological surveys).
(ii) At the first developing phase of the Met-Map (in 2001) the main aim is the map-like presentation of the new results and the contrasting metamorphic ages of the Units. The lithology has minor role in this context and an additional pattern may impede the readability of the maps.
(iii) Additional small maps (taken partly from publications) can contain the lithology of the most important key-areas.

— Why the intrusive rocks are presented on the Main maps?
The Met-Map has basically a geodynamic aspect. Because the magma generation is related to major crustal-scale processes, and the emplacement depth of igneous intrusions is often similar to the depth of metamorphism, the major bodies are indicated. The separation from volcanic rocks will be sometimes artificial.

— Why the contact metamorphism is not presented on the Main maps?
(i) The contact formations are usually complex and small in size, their presentation on a 1:1,000,000 map is difficult or impossible.
(ii) The formation and discovery of the contact zones is controlled by many factors and their existence is not very relevant in a geodynamic context.

— Why the Alpine and the Pre-Alpine metamorphism are on separate maps?
It is not a lucky solution, but in this way we can avoid to create a too dense, unreadable map. In a later phase they should be integrated in several smaller, more detailed areas.

— Why the European foreland is not presented?
Since the compilation of the first 'Map of Metamorphites of the Carpatho-Balkan-Dinaride Area' (Szádeczky-Kardoss et al., 1976) the majority of the new results were generated in the area of the Alpine orogen. The aim of the new Met-Map is to present these data.

— Why the Paleogene and the Neogene cooling events are not distinguished by areal colors?
It is obvious, that there was a fundamental change in the geodynamic scenario during the Paleogene. The actual age category of "Tertiary" is planned to be shared into two parts in a later developing stage. At the actual version the sporadic age data can be presented by point-like symbols (see Legend).

— Why the Cretaceous is subdivided into two age categories?
We have to consider how big is the age difference between the "classic" Eoalpine ages around 80 Ma and the older Cretaceous age group clustering around 140-120 Ma. This time span is as long as the whole Miocene + Oligocene + a part of the Eocene. The bimodality of the Alpine Cretaceous ages was already pointed out by Frank et al. (1987), suggesting a boundary at 95 Ma. The new division considers the boundary at 110 Ma. Both subdivisions are a bit artificial, because the exact geodynamic scenario is not yet known and the transition between the Late Jurassic-Early Cretaceous and the Late Cretaceous processes may have a time shift through the Met-Map area between the Alps and Hellenids. The advantages of the 110 Ma age boundary: (i) in the most studied Alpine areas all the basement formations underwent greenschist, amphibolite or eclogite facies "Eoalpine" metamorphism falls into the younger age category and (ii) the majority of the lower grade metamorphosed, mainly Paleozoic, metasedimentary formations (Upper Austroalpine and analogues) falls into the older Cretaceous age category. (iii): This older age category will contain also the HP metamorphic "Meliatic" and "Vardar" formations. This 150±10 Ma age group should be separated and indicated later with an other symbol.

— Why the areas covered by unmetamorphosed formations are also presented?
The Carpathian arc surrounds the Pannonian Basin System which occupies a significant part of the area of Met-Map. These covered areas carry essential information about pattern of metamorphism and thus, for the understanding of the evolution of the whole Carpathian-Dinaric realm.

— Why the Met-Map does not apply the color code of the 'Metamorphic Map of the Alps' (Frey et al., 1999)?
This would be a logic and elegant decision, but (i) the Met-Map considers the basement of the sedimentary basins that need other colors than the exposed areas, (ii) it does not show the lithology, and (iii) the Met-Map introduces other age categories (see Legend).