Trace fossils from the Lower and Middle Jurassic marginal marine deposits of the Sorthat Formation, Bornholm, Denmark

Bulletin of the Geological Society of Denmark

Petersen, K.S.¹  Símonarson, L. A.:¹  Böcher, J.¹  Israelson, C.¹  Funder, S, Bennike, O.¹ 

[1] Late Pliocene Greenland – The Kap København Formation in North Greenland. Bulletin of the Geological Society of Denmark, Vol. 48, pp. 117–134. Copenhagen.

关键词: Pliocene;    Praetiglian;    Tiglian;    palaeoenvironments;    sea-level change;    Greenland;   

学科分类：地球科学(综合)

来源: Dansk Geologisk Forening

【 摘 要 】

The Lower to Middle Jurassic Sorthat and Bagå Formations of the Baltic island of Bornholm, Denmark, are a predominantly fluviatile unit. On the south coast of the island at Korsodde, however, an interval within the Sorthat Formation contains a diverse trace fossil assemblage indicating a marine incursion. Study of this interval revealed 15 ichnotaxa, among which one is new: Bornichnus tortuosus nov. igen. et isp. Several of the trace fossils present are generally considered characteristic of the lower shoreface to offshore environments (e.g. Teichichnus and Asterosoma). However, the low degree of bioturbation and ichnodiversity, and sedimentological features, indicate an environment influenced by salinity fluctuation, probably a tidally influenced delta. Five ichnofabrics are defined that describe this setting and which may be indicative of marginal-marine environments that are influenced by salinity fluctuations.

【 授权许可】

Unknown