Portal de Periódicos da CAPES

Development of the Holocene foredune plain in the Narva-Joesuu area, eastern Gulf of Finland.

2012; Polish Geological Institute; Volume: 56; Issue: 1 Linguagem: Inglês

10.7306/gq.1077

2082-5099

Alar Rosentau, Argo Jõeleht, Jüri Plado, Raivo Aunap, Merle Muru, Kari O. Eskola,

Geological formations and processes

The morphogenesis and in ner struc ture of the Ho lo cene foredune plain in the Narva-Joesuu area, east ern Gulf of Fin land, were stud ied us ing op ti cally stim u lated lu mi nes cence (OSL) dat ing, ground-pen e trat ing ra dar (GPR) study and in ter pre ta tion of air borne LIDAR el e va tion data.The re sults show that the Narva-Joesuu foredune plain con sists of ca. 100 par al lel coastal foredune ridges built of well-sorted fine sand un der lain by gently (~7°) sea ward-dip ping sandy beach de pos its.The dis tal part of the plain, which con sists of at least 15 ridges, formed dur ing the re gres sive phase of the Ancylus Lake/Early Litorina Sea, serv ing as a bar rier for the la goon be hind it.A larger por tion of ridges, with an av er age progradation rate of 0.26 m a -1 , formed un der con di tions of fall ing rel a tive sea level dur ing the Litorina re gres sion and was sep a rated from the older foredune suc ces sion by a hi a tus re lated to the Litorina trans gres sion at 8.5-7.3 cal.ka BP.In the high est cen tral part of the plain the foredune growth was in ter rupted by foredune in sta bil ity and a re-blow ing ep i sode dated to 5.4 ± 0.9 ka BP which may cor relate with a larger re gional cool ing at 5.8-5.1 cal.ka BP in the North At lan tic and cen tral Eu rope.Dur ing the last 3000 years, the foredune progradation rate de creased to 0.19 m a -1 , most prob a bly be cause of de cel er ated land-up lift and in creased human im pact due to coastal pro tec tion.