Reconciliation of fossil assemblages and sedimentological data with the pal
eogeography of east-central Europe during the Middle Miocene has yielded a
new interpretation about paleotemperature. The Pannonian basinal system of
the Paratethys represents an unconventional and complex setting for cool wa
ter carbonate-siliciclastic sedimentation and volcanism, The Middle Miocene
Badenian Stage of Hungary is represented by four carbonate microfacies wit
hin the Pannonian basinal system. Algal rudstones and floatstones, composed
mostly of rhodolites, and bioclastic packstones, grainstones, and wackesto
nes, accumulated in distinct basins within a regional framework of synrift
tectonism, volcanism, and siliciclastic sedimentation. The diachronous natu
re of these deposits reflect the repeated connection and disconnection of t
he Paratethys.
Minimum sediment accumulation rates varied widely within the local basins o
f deposition (39-40 mm/1000 yr to < 1 mm/1000 Sr). A temperate type carbona
te basinal system is suggested by variations in faunal diversity, Heterozoa
n foramol biological associations dominated by red algal sediments, limited
development of Porites patch reefs, a relatively high paleolatitude, and h
igher global sea-level position for the Middle Miocene. Tectonism and the a
ccompanying changes in paleogeography, oceanic circulation, and upwellings
of colder water during drowning events may account for the paleoclimate rep
resented by the cool-water carbonate sediments of the Paratethys during the
Middle Miocene.