Wpływ wietrzenia dolnojurajskiego na złoża rud Zn i Pb w triasie śląsko-krakowskim

Abstract

INFLUENCE OF LOWER JURASSIC WEATHERING UPON ZN AND PB ORE DEPOSITS IN THE SILESIAN-CRACOW TRIASSIC Summary The article deals with the up-to-date problem of genesis and age of the Triassic zinc and lead ore deposits occurring in the Silesian-Cracow area. The materials analysed, taken from numerous bore holes, made possible to investigate in the detail the problem of influence of the Lower Jurassic weathering process upon the zinc and lead deposits of the area discussed. This led to the following conclusions: 1. On account of a making destruction process at the Lower Jurassic time, the age of the Triassic deposits should be accepted as a pre-Jurassic one. 2. A considerable amassment of limonite ores being an oxidation product of zinc and lead deposits in the continental Liassic formations speaks of a fact that some rich ore zones have been formed already at the Triassic time. 3. On account of the pre-Jurassic age of the zinc-lead ores occurring in the Silesian-Cracow region, their genesis cannot be related to the Alpine metallogeny cycle and to the faults of that period.