Naslov
Seismic-scale basin-fill architecture in the Late Neogene Lake Pannon SW Pannonian basin, Croatia

Autori
Špelić, Marko ; Sztanó, Orsolya

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, ostalo

Izvornik
34th IAS Meeting of Sedimentology Rome / Abstract book / - Rim : Sapienza Universty Rome, 2019, 1087-1087

ISBN
978-88-944576-2-9

Skup
34th IAS International Meeting of Sedimentology

Mjesto i datum
Rim, Italija, 10.09.2019. - 13.09.2019

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Lake Pannon, Late Miocene, Pliocene, seismic geomorphology, clinoforms

Sažetak
The vast and deep Lake Pannon has been gradually filled in during the Late Miocene to Pliocene. Driving mechanism was large sediment input, exceeding creation of accommodation, and manifested by the large-scale clinoforms of shelf-margin progradation. Despite various studies by means of seismic stratigraphy, sedimentology and palaeontology, factors controlling basins fill architecture in various parts of Pannonian basin system are still controversial. The study of the clinoform succession, the shelf-edge trajectory in particular provides understanding of base- level variations, local structural movements and the spatial distribution of paleoenvironments.The study area is situated in Eastern part of the Drava basin. 3D seismic cubes were analysed in the time domain, covering the mapped area of more than 140 km. Standard procedures – well to seismic tie via VSP and checkshots data ; stratigraphic reports ; seismic stratigraphy techniques – were used, time-structure and RMS amplitude maps were constructed. Numerous horizons were mapped, from which two generations of clinoforms can be distinguished: a large and a small set. The first generation consists of sigmoidal clinoforms, indicating a water depth of ca. 610 m. The shelf-margin trajectory is flat until maximum regression was reached. The second generation is of small oblique ones pointing to a depth of ca. 190 m. These downlap on the old ones, but gradually their height is increasing as overtaking the old ones with parallel development of a sigmoidal geometry.The prograding slope reached the area after 6.8 Ma, but before the start of basin inversion at about 5.3 Ma ago, so no major structural complication is expected. Stratal stacking patterns and the shelf-margin trajectory reveal changes of lacustrine base-level. A clinoform progradation with flat trajectory to maximum regression points to steady base level. Afterwards flooding occurred with a base level rise of 200 m. This event generated accommodation for the smaller set of clinoforms, which continued progradation during the next period of steady base level. In Lake Pannon similar events of base-level rise are common, yet usually far less than 100 m. Seismic-scale deltaic clinoforms in the topsets of shelf-margin clinoforms were described only from a few other locations.This is the first detailed seismic study to document shelf-slope progradation in the SW part of the Pannonian basin system. Moreover, it is suggesting that, steady and rising base level were alternating during the progradation, but in this case, a higher than usual rise is documented. The Croatian Hydrocarbon Agency and Ministry of Economy, Entrepreneurship and Crafts provided data. Cooperation was supported via Hungarian- Croatian bilateral project (Stratigraphy and correlation of Upper Miocene-Pliocene sediments along the Croatian-Hungarian border and TÉT_16- 1- 2016-0004), the TEMPUS Foundation and Hungarian NKFI 116618. The academic license of Petrel Schlumberger is also acknowledged.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA