In this master's thesis I performed sedimentological and biostratigraphical analysis of Jurassic limestones on Mt. Matajur. The succession was correlated with Dinaric Carbonate Platform, Julian High and Slovenian Basin. Investigated area is located on the northern slope of Mt. Matajur. Structurally, it belongs to the External Dinarides, most likely to the highest Trnovo Nappe. The area of Mt. Matajur paleogeographically belongs to the transitional zone between the northern margin of the Dinaric Carbonate Platform and the Julian High.
The Matajur section starts with Lower Jurassic platform limestone of Lithostratigraphic unit 1. Prevailing grains are ooids and bioclasts. Some oncoids may occur as well. Sedimentation took place in lagoon, with occasional emersion on one side and deposition of high energy sediments on the other side. Age of lithostratigraphic unit 1 was determined on the basis of foraminifers. Lithostratigraphic unit 2 comprises hemipelagic limestones, breccias and calcarenites beds. It starts with a breccia layer, followed by bedded and nodular micritic limestone, intercalated with calcarenite beds. The unit ends with a large section of limestone breccias. Clasts in breccias are in the lower part mostly lithoclasts from Lithostratigraphic unit 1 and 2 and bioclasts in the upper part of the unit. Grain in matrix are mostly ooids. Sedimentation occurred on submerged plateau, which was still connected to the Dinaric Carbonate Platform in the hinterland. Age of the Lithostratigraphic unit 2 is Middle Jurassic. Lithostratigraphic unit 3 comprises nodular and micritic limestones with chert. Some calcarenites and limestone breccias with “Tubiphytes” are present in the lower part. The most common grains are pelagic crinoids Saccocoma sp. based on these, the unit in Late Jurassic in age. Lithostratigraphic unit 4 comprises Upper Jurassic and Lower Cretaceous micritic Biancone Limestone. Matajur section ends with Upper Cretaceous limestone breccia of the Upper flyschoid formation.
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