ASGP (2009), vol. 79: 1-11

TRACE FOSSILS FROM SILURIAN AND DEVONIAN TURBIDITES OF THE CHAUVAY AREA, SOUTHERN TIEN SHAN, KYRGYZSTAN

Michał WARCHOŁ (1) & Stanisław LESZCZYŃSKI (2)

1) Institute of Geological Sciences, Polish Academy of Sciences, ul. Senacka 1, 31-002 Kraków, Poland, e-mail: ndwarcho at cyf-kr.edu.pl
2) Institute of Geological Sciences, Jagiellonian University, ul. Oleandry 2a, 30-063 Kraków, Poland, e-mail: stan.leszczynski at uj.edu.pl

Warchoł, M. & Leszczyński, S., 2009. Trace fossils from Silurian and Devonian turbidites of the Chauvay area, southern Tien Shan, Kyrgyzstan Annales Societatis Geologorum Poloniae, 79: 1-11.

Abstract: The siliciclastic turbidite successions (Pul’gon and Dzhidala Formations) that crop out in the eastern part of the Chauvay River valley, are marked on geological maps as a belt of terrigenous deposits of Silurian–Devonian age. They resemble deposits of overbank areas and depositional lobes of deep sea fans, and display common trace fossils particularly on lower surfaces of sandstone beds. Sixteen ichnotaxa representing four morphological groups have been distinguished. The trace fossil assemblages suggest their affiliation to the Nereites ichnofacies. Various branched, preturbidite forms predominate in both examined units, although the assemblages of individual units differ slightly in composition. In the Pulg’on Formation, small, densely distributed burrows commonly occur on lower surfaces of sandstone beds. Shallow burrowing depth together with relatively low diversity trace fossil assemblages indicate lowered oxygenation of the sea floor.