Conference:
EEDEN, State of the art, 16-18 November 2000, Lyon, France, p. 52.
Author:
Speranta-Maria Popescu.
Abstract:
High-resolution pollen analysis has been performed on the Lupoaia section, which runs from lignite V to lignite XIII (thickness: 123m) of the western Dacic Basin (Motru area). This area belongs to a Zanclean paleo-delta, which was built by a tributary of the paleo-Danube. Paleomagnetic measurements have been successively realized by by Radan & Radan (1986) and van Vught (2000), which are in good agreement. Paleoclimatic interpretations of the pollen diagrams supports that the two successive normal chrons belong to the C3n.3n and C3n.2n, that is in agreement with mammal remains in the area.
Pollen flora is very rich and shows repetitive and almost regular alternations of: (1) thermophilous trees and altitudinal trees; (2) subtropical swamps forest phases and open vegetation phases. The first alternations have been forced by eccentricity (100 kyrs) as also the repetitive lignite-clay clusters correspond to changes in temperature. The second ones have been forced by precession (20 kyrs) and are expanded by swampy (Taxodiacea forests) assemblages competing with marshy (herbaceous mainly Cyperaceae) assemblages in relation with changes in moisture (monsoon influence?). Such assemblages exist today in the Mississippi delta.