Academic Journals Database
Disseminating quality controlled scientific knowledge

Shallow water carbonate platforms (Late Aptian, Southern Apennines) in the context of supraregional to global changes

ADD TO MY LIST
 
Author(s): A. Raspini

Journal: Solid Earth Discussions
ISSN 1869-9537

Volume: 3;
Issue: 2;
Start page: 901;
Date: 2011;
VIEW PDF   PDF DOWNLOAD PDF   Download PDF Original page

ABSTRACT
A preliminary study based on the comparison of recently published δ13C record of the Late Aptian Monte Tobenna and Monte Faito sections (Southern Italy) with reference carbon isotope curves reveals how sea-level fluctuations played a fundamental role in regolating the carbonate sedimentation in the inner lagoonal environments of the Apenninic platform and the occurrence of some peculiar facies during a time of increasing volcano-tectonic activity and trophic levels of the water. During the lowering of the sea level, microbial carbonates were a common product of the shallow marine ecosystem in a general context of deterioration of the inner lagoon environmental conditions. When trophic levels were too high, due to the decisive contribution of a supraregional dictator (e.g. increase of the precipitation rate), and the environmental conditions were unsuitable for the main carbonate producers of the inner lagoonal settings, the Orbitolina (Mesorbitolina parva and Mesorbitolina texana) level formed, just before the minimum accommodation space on the platform was reached and fresh/brackish water environments spread. In deposits underlying the orbitolinid-rich facies of the carbonates studied, Salpingoporella dinarica alga is widespread, possibly due to the seawater's chemical composition that could have encouraged the development of its low-Mg calcite skeleton. On the contrary, during periods of sea level rise (and early highstand) no or minor microbial carbonates formed in the shallow lagoonal settings that were not influenced by the paleoenvironmental changes mostly induced by the mid-Cretaceous volcanism, and therefore easily remained in a healthy state.

Tango Rapperswil
Tango Rapperswil

     Save time & money - Smart Internet Solutions