from the Oligocene Siebengebirge Volcanic Field (Germany): Implications for the Origin of Intracontinental...UNIVERSITA«T BONN, POPPELSDORFER SCHLOSS, 53115 BONN, GERMANY 2 OMYA DEVELOPMENT AG, BASLERSTRASSE 42, 4665...MINERALOGIE, ZU«LPICHER STR. 49A/B, 50674 KO«LN, GERMANY 5 INSTITUT FU«R MINERALOGIE, UNIVERSITA«T MU«NSTER...MU«NSTER, CORRENSSTRASSE 24, 48149 MU«NSTER, GERMANY RECEIVED JUNE 27, 2011; ACCEPTED JULY 11, 2012 ADVANCE...volcanic provinces in Central Germany, such as the Eifel, Rho«n, Vogelsberg, Westerwald, and Eger Rift complexes |