Palaeodrainage systems at the basal unconformity of the Bohemian Cretaceous Basin: roles of inherited fault systems and basement lithology during the onset of basin filling

Abstract

This study presents a synthesis of currently available data on the distribution of Cenomanian-age palaeodrainage systems in the Bohemian Cretaceous Basin, filled by fluvial and estuarine strata, and an interpretation of their relationships to the basement units and fault systems. Much of the progress, compared to previous studies, was made possible by a recent basin-scale evaluation of Cenomanian genetic sequence stratigraphy. Several local palaeodrainage systems developed in the basin, separated by drainage divides of local importance and one major divide -the Holice-Nové Město Palaeohigh -which separated the drainage basins of the Tethyan and Boreal palaeogeographic realms. The locations and directions of palaeovalleys were strongly controlled by the positions of inherited Variscan basement fault zones, whereas the bedrock lithology had the subordinate effect of narrowing or broadening valleys on more vs. less resistant substratum, respectively. The intrabasinal part of the palaeodrainage network followed the slopes toward the Labe (Elbe) System faults and was strongly dominated by the conjugate, NNE-trending, Jizera System faults and fractures. Outlet streams -ultimate trunk streams that drained the basin area -are interpreted to have followed the Lužice Fault Zone toward the Boreal province to the Northwest, and the Železné hory Fault Zone toward the Tethyan province to the Southeast. At both the northwestern and southeastern ends of the Bohemian Cretaceous Basin, shallow-marine or estuarine conditions are proven to have existed during the early Cenomanian. Direct evidence for syn-depositional subsidence during the early to mid-Cenomanian, fluvial to estuarine phase is very rare, and the onset of deposition by fluvial backfilling of the palaeodrainage systems was driven mainly by the long-term rise in global sea level. Subtle surface warping, mostly without detectable discrete faulting, is inferred to have been a response to the onset of the palaeostress regime that later, with further stress accumulation, led to subsidence in fault-bounded depocentres of the Bohemian Cretaceous Basin and uplift of new source areas. •

Pseudoasterophyllites cretaceusfrom the Cenomanian (Cretaceous) of the Czech Republic: A possible link between Chloranthaceae andCeratophyllum

“…Its age is bracketed above by ammonites of the late Cenomanian Calycoceras guerangeri and Metoicoceras geslinianum zones in the Korycany and Pecínov members of the formation (Čech, 2011). Palynological data indicate a late middle Cenomanian age for these beds (Pacltová, 1977(Pacltová, , 1978, and sequence stratigraphic analyses by Uličný & al. (2009) indicate that they belong to the CEN 4 cycle of late middle Cenomanian age.…”

“…Geological and sequence stratigraphic analyses indicate that the Peruc-Korycany Formation represents a series of paleovalley infills (Uličný & Špičáková, 1996; Uličný & al., 2009). These successions comprise deposits of a variety of continental (braided rivers, meandering streams and floodplains, and anastomosed fluvial systems) and coastal environments (tidally influenced braided rivers, supratidal salt marshes, tidal flats, ebb-tidal deltas, estuaries, and lower shoreface) (Uličný & al., 1997).…”

Provenance of Upper Cretaceous quartz-rich sandstones from the North Sudetic Synclinorium, SW Poland: constraints from detrital tourmaline

“…Ulièný et al (2009b) doc u mented a pe ne plain in the northwest ern Bo hemian Mas sif with the deep est val leys less than 90 m be low the sur round ing ter rain; in some places kaolinite-rich regoliths up to sev eral tens of metres thick are still pre served un der Cre taceous rocks. Al though such thick regoliths are not pre served in the Pol ish part of the Sudetes, their for mer oc cur rence in the Late Cre ta ceous is highly prob a ble (Migoñ and LidmarBergström, 2002).…”

“…The pre dom i nance of subangular quartz and an gu lar tour ma line grains in di cates rel atively short trans port and con tra dicts mul ti ple re cy cling. Variscan crys tal line rocks did oc cur at the sur face in some parts of the Bo he mian Mas sif in the Late Cre ta ceous (e.g., Gierwielaniec and Turnau-Morawska, 1961;Gorczyca-Ska³a, 1977;Ulièný et al, 2009b). In the Sudetes, they con sti tuted the base ment of a part of the Cenomanian and Turonian de pos its.…”

Synsedimentary seismotectonic features in Triassic and Cretaceous sediments of the Intrasudetic Basin (U Devíti křížů locality) – regional implications

“…This is also ev i denced by biogenic struc tures, in clud ing trace fos sils such as Thalassinoides and Arenicolites, and root casts, which in di cate a shallow-ma rine, nearshore en vi ron ment (cf. Mikuláš and Prouza, 1999;Ulièný et al, 2009). These struc tures oc cur in the sandstones be low a thin, up to 0.3 m thick con glom er ate bed (Fig.…”