Distal turbidite fan/lobe succession of the Late Oligocene Zuberec Fm. – architecture and hierarchy (Central Western Carpathians, Orava–Podhale basin)

Abstract

A part of the Upper Oligocene sand-rich turbidite systems of the Central Carpathian Basin is represented by the Zuberec Formation. Sand/mud-mixed deposits of this formation are well exposed in the northern part of the basin, allowing us to interpret the turbidite succession as terminal lobe deposits of a submarine fan. This interpretation is based on the discrimination of three facies associations that are comparable to different components of distributive lobe deposits in deep-water fan systems. They correspond to the lobe off-axis, lobe fringe and lobe distal fringe depositional subenvironments, respectively. The inferences about the depositional paleoenvironment based on sedimentological observations are verified by statistical analyses. The bed-thickness frequency distributions and vertical organization of the facies associations show cyclic trends at different hierarchical levels that enable us to reconstruct architectural elements of a turbidite fan. First, small-scale trends correspond with shift in the lobe element centroid between successive elements. Differences in the distribution and frequency of sandstone bed thicknesses as well as differences in the shape of bed-thickness frequency distributions between individual facies associations reflect a gradual fining and thinning in a down-dip direction. Second, meso-scale trends are identified within lobes and they generally correspond to the significant periodicity identified by the time series analysis of the bed thicknesses. The meso-scale trends demonstrate shifts in the position of the lobe centroid within the lobe system. Both types of trends have a character of a compensational stacking pattern and could be linked to autogenic pro-*Corresponding Author: Dušan Starek: Earth Science Institute SAS, Geological Division, Dúbravská cesta 9, 842 36 Bratislava; Email: dusan.starek@savba.sk Tomáš Fuksi: Earth Science Institute SAS, Geological Division, Dúbravská cesta 9, 842 36 Bratislava cesses. Third, a largescale trend documented by generally thickening-upward stacking pattern of beds, accompanied by a general increase of the sandstones/mudstones ratio and by a gradual change of percentage of individual facies, could be comparable to lobe-system scale. This trend probably indicates a gradual basinward progradation of lobe system controlled by allogenic processes related to tectonic activity of sources and sea-level fluctuations.

Turbidite sedimentology, biostratigraphy and paleoecology: A case study from the Oligocene Zuberec Fm. (Liptov Basin, Central Western Carpathians)

“…Paleocurrent measurements point to the main transport of the material from SW and W which is generally consistent with the measurements of paleocurrents in the Orava-Podhale part of the CCPB (cf. Marschalko & Radomski 1960;Starek 2001;Starek & Fuksi 2017a). Uniform paleotransport mode suggests that the Liptov and Orava-Podhale sub-basins formed one sedimentary area without distinctive segmentation during the Oligocene.…”

Statistical characterization of a confined submarine fan system: The Pennsylvanian Lower Atoka Formation, Ouachita Mountains, USA

“…Statistical methods based on bed-by-bed measurements have become increasingly insightful in understanding several key aspects of submarine fan systems. These aspects include the discrimination of the fan subenvironments (Carlson & Grotzinger, 2001;Chen & Hiscott, 1999a;Clark & Steel, 2006;Felletti & Bersezio, 2010b;Fryer & Jobe, 2019;MacDonald, 1986;Malinverno, 1997;Sylvester, 2007), quantification or semi-quantification of the degree of confinement (Felletti & Bersezio, 2010a;Fryer & Jobe, 2019;Liu et al, 2018;Marini et al, 2016;Sinclair & Cowie, 2003;Tőkés & Patacci, 2018), objective detection of stratigraphic patterns (Chen & Hiscott, 1999a;Amy et al, 2000;Wilkinson et al, 2003;Sumner et al, 2012;Burgess, 2016a;, and separation of the influence of potential control mechanisms (Weltje & Boer, 1993;Stow et al, 2002;Dennielou et al, 2006;Starek & Fuksi, 2017;Burgess et al, 2019).…”

“…Currently, studies with integrated statistical analyses either utilize only a small number of outcrops (Starek & Fuksi, 2017;Palozzi et al, 2018;Bourli et al, 2019) or only partially address these aspects of depositional systems (Pantopoulos et al, 2013(Pantopoulos et al, , 2018 The purpose of this study is to integrate the established statistical methods, improve them by testing against a well-understood submarine fan system, and enhance the understanding of the depositional system and control mechanisms. This study uses a large (> 2,500 m measured sections) outcrop dataset from the Pennsylvanian, synorogenic lower Atoka submarine fan succession of the Ouachita Mountains in the United States, where the structural-depositional framework is well-documented (Houseknecht, 1986;Coleman, 2000;Arbenz, 2008;Hou et al, 2020).…”

“…Statistical methods based on bed‐by‐bed measurements have become increasingly useful in understanding several key aspects of submarine fan systems. These aspects include the discrimination of the fan subenvironments (MacDonald, 1986; Malinverno, 1997; Chen & Hiscott, 1999a; Carlson & Grotzinger, 2001; Clark & Steel, 2006; Sylvester, 2007; Felletti & Bersezio, 2010a; Pantopoulos et al ., 2018; Fryer & Jobe, 2019), quantification or semi‐quantification of the degree of confinement (Sinclair & Cowie, 2003; Felletti & Bersezio, 2010b; Marini et al ., 2016; Liu et al ., 2018; Tőkés & Patacci, 2018; Fryer & Jobe, 2019), objective detection of stratigraphic patterns (Chen & Hiscott, 1999b; Amy et al ., 2000; Wilkinson et al ., 2003; Sumner et al ., 2012; Burgess, 2016a,b) and separation of the influence of potential control mechanisms (Weltje & Boer, 1993; Stow et al ., 2002; Dennielou et al ., 2006; Starek & Fuksi, 2017; Burgess et al ., 2019). Currently, studies with integrated statistical analyses either utilize only a small number of outcrops (Starek & Fuksi, 2017; Palozzi et al ., 2018; Bourli et al ., 2019) or only partially address these aspects of depositional systems (Pantopoulos et al ., 2013, 2018).…”

“…(d) the Kernel Density Estimations (KDE) of the periodicities by different methods show consistent results, based on all ordered sections of the lower Atoka. Inspired by Li et al (2019) andStarek & Fuksi (2017).…”