Additional palynological data on the age of the Razhcha Formation, Osogovo Mts., West Bulgaria
1997; Volume: 27; Issue: 1-2 Linguagem: Inglês
10.52321/geolbalc.27.1-2.36
ISSN2535-1060
Autores Tópico(s)Geological and Geochemical Analysis
ResumoAdditional palynological data on the age of the Razhcha Formation, Osogovo Mts, West BulgariaThe age of the low-grade metamorphic rocks of the Razhcha Formation (various types of schists and quartzites) have been questionable for long time.Primarily it was supposed to be Precambrian based on scarce acritarch findings on the territory of the Republic Macedonia.The palynological assemblage reported by Lakova et al. ( 1995) from the sample 242 at the locality Rasovo, Gucshevo area, West Bulgaria, determined the age of the Ra zhcha Formation within the time interval from Wen lockian to Early Devonian.The age detennination was proposed mainly on the occurrence of relatively longerranging acritarch species.A recently undertaken study on the trilete miospores from the same assemblage of sample 242 has enabled a further age specilication.The palynological preparations contain the species Emphani.\porites zavalla/us Richardson, Street.Hassan & Stteemans.1982, a coarsely sculptured Emphunisporites, which is a very characteristic biostratigraphic marker.The time span of this miospore species is restricted at the end of Lochkovian.It is an index-species of the latest Lochkovian Breccmisporites breconensis-Emplwnisporites ~a vallatu.~•Assemblage Miospore Zone introduced by Richardson & McGregor (1986) andrecognized in Belgium.south Wales, Po\and (Turnau, Jakubowska.1989) and the subsuface of the Moesian Platform in Romania.Undeterminable zonate miospores are also present.It is to be mentioned that in the sporomorph evolution the iru;oming of zona (prominent equatorial cingulum) occurred not earlier than the beginning of Lochkovian (Richardson, 1996).
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