Gondwana 15 – North meets South
Congress - 14th - 18th July/2014
In process of forming the database, the second draft of Gondwana Map did not suffer meaningful changes from the previous version. The maps were going through the process of generalization, especially Brazil, which was still being simplified. The change was the unification of Cenozoic’s units. The African continent was the most worrisome about the difficulty of getting data. The polygons were classified by the age and the type of rock. The colors represent the protolith’s age according to IUGS International Chronostratigraphic Table using a 35% of transparency in the colors. The available data on our database was not enough to implement all the legend information. In order to allow a preliminary visualization of the reconstruction, the software GPlates using Seton et al. (2012) model in 150 Ma with fixed Africa’s plate was chosen. Despite the map’s work scale being 1:5M, it was presented in the polyconic projection on the scale 1:10M for the visualization of the work in progress.
During the IGCP628 session, the draft version 1.2 of the new map of Gondwana was presented, which the main focus was the discussion of the legend and the geology. Therefore, some relevant questions have been raised: a) the use of maps in bigger scales than 1:1M due to the time it takes to make compilation; b) the attributes that will be used to represent on map which will define the legend; c) to define the information that will be represented on the map, for example, the units smaller than the map’s age should be shown; d) the best age to represent Gondwana in the reconstruction.