In this paper we describe a fossil graben and associated normal faults and joints. The graben occurs in the section of the Vistulian (Weichselian) and Holocene sediments in an archaeological excavation site at Brzezie, in the central part of the Polish Carpathian Foredeep (Wieliczka-Gdów Upland, western part of the Sandomierz Basin). Normal faults strike mostly NNE-SSW and dip steeply about 65 - 850. Some of them, namely master normal faults, bound the fossil graben. The joints form orthogonal pattern and are closely spaced close to the faults. They developed simultaneously with faulting. Normal faulting took place during the Vistulian - Mesoholocene (Neoholocene?) time, according to age of the archaeological artefacts which were found in the faulted sediments. The faulting was probably finished during the Neolithic or even later, during the Bronze Age. The NNE-striking normal faults connected with graben formation could have been produced by reactivation of a NE-striking sinistral regional fault in the basement.

The paper aims at reconstructing Pleistocene slope processes and transformation of tectonic relief in two sections across the northern margin of the Krzeszowice Graben. The investigations are based on the analysis of deposits present on the slopes of fault-line scarps. The lithology and stratigraphy of these deposits was reconstructed based on analysis of outcrops and boreholes. Detailed lithological logs were prepared, along with grain size analyses, and determination of CaCO3, Fe2O3 and Corg contents in fine-grained sediments. The studied fault-line scarps were transformed by Pleistocene denudation. The type and intensity of these processes were different in the sections studied. In the Będkowice area, accumulation prevailed; the fault-line scarp became covered with sediments. In the Karniowice area, in turn, periglacial processes caused degradation of the fault-controlled slope. In the lower part of the fault-line scarp, the intensity of degradation processes was limited by repeated presence of sediment cover which preserved the substratum. Differences in the intensity and type of Pleistocene denudation can be explained by different heights of fault-line scarps, controlled by tectonic structure and neotectonic movements.