Facies and Facies Architecture of the Ivanić Grad Formation (Upper Pannonian) - Sava Depression, NW Croatia

Abstract

Four facies were distinguished within the Ivanić Grad Formation of the Sava Depression: massive marl facies (F1), thick-bedded to massive sandstone facies (F2), thin-bedded sandstone facies (F3) and thin bedded sandstone, siltite and marl facies (F4). Interpretation of the depositional mechanisms confirmed the presence of two basic sedimentary processes. Hemipelagic deposits are represented by finegrained detritus. The lithification of these produced a massive marl (facies - F1). Sand detritus was transported into the depression by turbidite currents (facies - F2- F4), and formed a narrow elongated sedimentary body. By comparing the facies defined on the basis of core samples, the spontaneous-potential curve (SP) and the resistivity curve (Ra) of identical intervals, four facies associations were defined on well log diagrams: channel filling (FA), depositional lobe (FB), lateral and distal turbidites (FC) and massive marls (FD).