Pučinski taložni prijelaz iz krede u paleogen (otok Svetac, Jadransko more)

undergraduate thesis

• Title (english): Pelagic sedimentary transition from Cretaceous to Paleogene (Svetac Island, Adriatic Sea)
• Author: Lovro Suić
• Mentor: Damir Bucković (mentor)
• Committee member: Damir Bucković (predsjednik povjerenstva)
• Committee member: Aleksandar Mezga (član povjerenstva)
• Committee member: Dražen Kurtanjek (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Geology); Zagreb
• Defense date and country: 2024-09-10, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Geology

Abstract

Pučinski karbonati stratigrafskog raspona mastriht-paleocen na srednjojadranskom otoku Svetac jedini su dosad pronađeni izdanci koji dokumentiraju pučinsko taloženje tijekom prijelaza krede u paleogen unutar Jadranskog bazena. Istraženi sljed naslaga debljine oko 3 m izgrađuje bogat i raznolik planktonski biofacijes što omogućava njegovo datiranje i odredbu biostratigrafskih zona. Najdonji dio slijeda sastoji se od 1.5 m debelog pelagičkog biomikrita bogatog planktonskim foarminiferama mastrihtove Abatomphalus mayaroensis zone. Zatim slijede dvaju interkalacija floatstona, oko <0.5 m debljine svaki, u čijim su intraklastima, koji plutaju u biomikritnom matriksu, pronađene i identificirane planktonske foraminifere mastrihta. U matriksu prve interkalacije su samo planktonske foraminifere mastrihta, dok su u matriksu druge interkalacije mješane planktonske foraminifere mastrihta i paleocena. Ta tranzicija nije kontinuirana, ali smatra se da je povezana s dva odvojena događaja pretaloživanja u Jadranskom bazenu. Na njima leži pelagički biomikrit 1 m debljine u kojemu je bogatstvo planktonskih foraminifera paleocena karakteristično za paleocensku P3 zonu. Dva metra dalje, nakon pokrivenog izdanka, nalaze se eocenski pelagički biomikriti s planktonskim foraminiferama koje ukazuju na eocensku E9 zonu zbog plutajućih Discocyclina u matriksu. Smatra se da je taloženje ovih dvaju interkalacija tijekom prijelaza mastriht-paleocen u dubokom moru na kosini Jadranskog bazena povezano s reaktivacijom transverzne rasjedne zone.

Abstract (english)

The pelagic carbonates, ranging from Maastrichtian to Paleocene, found on the Adriatic island of Svetac, are the only outcrops discovered so far that document offshore sedimentation during the Cretaceous-Paleogene transition within the Adriatic Basin. The investigated sedimentary sequence consists of a rich and diverse planktonic biofacies, which allows for its dating and determination of biostratigraphic zones. The lowermost part of the sequence consists of a 1.5 m thick pelagic biomicrite rich in planktonic foraminifera from the Maastrichtian Abatomphalus mayaroensis zone. This is followed by two intercalations of floatstone, which contain Maastrichtian planktonic foraminifera within the intraclasts floating in the biomicrotic matrix. In the matrix of the first intercalation, only Maastrichtian planktonic foraminifera are present, while in the second intercalation there is a mix of Maastrichtian and Paleocene planktonic foraminifera. This transition is not continuous, but is considered to be associated with two separate re-depositional events in the Adriatic Basin. Above, lies a 1 m thick pelagic biomicrite containing Paleocene planktonic foraminifera, characteristic of the Paleocene P3 zone. Nearby, there are Eocene pelagic biomicrites with planktonic foraminifera indicating the Eocene E9 zone, with Discocyclina in the matrix. It is thought that the deposition of these intercalations is associated with the reactivation of the transverse fault zone.

• Keywords: Jadranska platforma i bazen; kreda; paleogen; planktonske foraminifere
• Keywords (english): Adriatic Platform and Basin; Cretaceous; Palaeogene; planktonic foraminifera
• Language: croatian
• URN:NBN: urn:nbn:hr:217:033827
• Study programme: Title: Geology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) geologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) geologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2025-02-04 13:55:13