MILIOLIDAE - Acta Palaeontologica Polonica

MILIOLIDAE FROM MIOCENE OF POLAND 15
Lower Tortonian
Zone with Orbulina suturalis. - The Lower Tortonian deposits abounding
in the Miliolidae occur only in the northern and southern marginal
zones, being rare in the central part of the Precarpathian Foredeep. The
miliolids from the clayey-marly formations of Karsy and Korytnica near
J~drzejow make a typical example of the assemblages of the northern
coastal facies. They are mainly numerous Quinqueloculina species, such
as Q. alexandri QS and MS, Q. anagallis, mostly MS, Q. buchiana, mostly
QS, Q. dichotoma QS and MS, Q. lentica QS and MS, Q. parakneriana,
mostly QS, Q. peregrina MS, Q. pseudobuchiana QS and MS and abundant
Cycloforina badenensis, C. reticulata, C. vermicularis, Lachlanella incrassata,
L. schroekingeri and Sigmoilopsis foeda. A similar miliolid
assemblage is met with in the bottom portion of the clayey deposits in
the Miocene of the Holy-Cross Mts, between Tarnobrzeg and Chmielnik
(bore holes: Mlyny 1, Budy 1 and Grabki Duze N8). The miliolid fauna
of the southern coastal region of the Lower Tortonian is exemplified by
the assemblage from the clayey sediments of Benczyn near Wadowice,
composed chiefly of the same species as the assemblages from Korytnica
and Karsy area. Species known from Korytnica - Quinqueloculina
anagallis QS, Q. buchiana QS and MS, Q. haidingeri MS, Q. lentica QS,
Q. parakneriana QS, Q. pseudobuchiana QS, Siphonaperta mediterranensis,
Sigmoilopsis foeda, Sinuloculina consobrina and Sigmoilinita tenuishave
also been found in the clay deposits of the bottom portion of the
Lower Tortonian in bore-hole L~ki Dolne-1 near Tarnow.
Special attention should be given to the fact that the Miliolidae are
very rare in the Heterostegina sands of the Cracow-Miech6w region and
in marly and sandy limestones or limestones of the Miech6w region and
the Holy-Cross Mts, although these also constitute coastal facies of the
Lower Tortonian. The Miliolidae are lacking or represented by only few
common species, like Sigmoilinita tenuis or Sinuloculina consobrina, in
the microfaunal assemblages consisting chiefly of planktoni~ foraminifera
in the central part of the Foredeep.
Zone with Uvigerina costai. - In the upper layers of the Lower
Tortonian the assemblage of miliolids becomes impoverished all over the
area of the occurrence of the Miocene deposits and it shows no differentiation
into shallower and deeper facies. The microfauna of the salt clays
of Wieliczka, where the Miliolidae are relatively more numerous than in
other localities but all the same limited to a small number of species,
is a typical exemplary assemblage of this zone. It contains, above all,
numerous specimens of Quinqueloculina akneriana QS and very rare MS,
Q. triangularis QS and rare MS, a small number of Q. haidingeri QS and
MS, and typical species of these layers: Q. pygmaea, Q. regularis,