Outline of tectonics of the outer zone, the Carpathian foretrough

Abstract

The edge trough in the East Carpathians includes an inner zone that developed adjacent to the Carpathian geosyncline, a deep trough filled with thick Miocene and Pliocene sediments. The Miocene beds have been extensively folded and overthrust. The edge trough also includes an outer zone which is the depressed edge of the platform covered by Tortonian and Sarmatian sediments. The structure and geologic history of the platform part of this trough is based on much borehole data and detailed geologic and geophysical surveys. The stratigraphy is discussed and thicknesses of the Tortonian and lower Sarmatian for different localities are given in Table 1. Figure 1 shows the structure of the outer zone; contours are drawn on top of the Tiras (gypsum-anhydrite) formation. Several zones of rapidly varying thickness in the Tortonian and lower Sarmatian sediments correspond to major northwest striking basement faults, which are responsible for the block structure of much of the outer zone. These basement faults, firs...