The elevation with the Lichnice Castle (
visit link) allows to overview a broad area stretching across the southwestern foothills of the Iron Mountains. Geological basement of this site is formed by the oldest metamorphic rocks, generally called gneisses.
A prominent tectonic structure called the Železné hory Fault stretches in northwest–southeast direction along the foothills of the Iron Mountains. The block of the Iron Mountains was uplifted along this fault by at least 600–800 m. This process can be also described as an event during which the Iron Mountains rose by hundreds of metres above the surrounding landscape. This event lasted millions of years. As the mountains were rising, the stream network was changing, too. In this case, the Chrudimka and Doubrava rivers shifted their channels.
Deep-reaching faults are usually associated with the ascent of metal-bearing fluids. Ore deposits with mineral accumulations enriched in zinc, lead, silver, copper and barium were formed. These deposits were exploited as early as in the Celtic period. By any means, iron ore mining and occurrences of iron-bearing minerals pre-determined the name of the mountains.
The search in quest of the Proterozoic can be therefore best started at the Lichnice Castle: gneiss outcrops of the Lovetínská Gorge are indeed unique, and were also used for the construction of the castle walls. The gneisses were formed by metamorphism of sedimentary and volcanic rocks more than 550 million years ago. The Lichnice Castle provides a view over the prominent crest of the Iron Mountains between Chvaletice and Slavíkov. This great view makes this site one of the most attractive within the Iron Mountains National Geopark. Proterozoic rocks fill one's sight completely.
The no-service information stand consists of a wooden structure with five panels generally expanding the theme of the Proterozoic. These panels refer to nine geosites in the Iron Mountains with installed information panels reporting on closely accessible phenomena related to the period “preceding the trilobites?.
Blocks of rocks from the territory of the Iron Mountains are scattered around the wooden structure, totalling 10 accessible samples from 7 sites. They include weakly metamorphosed sediments, volcanics, gneisses and metabasic rocks. The blocks are mostly polished, and always provided with an information pillar. The pillars comment on the origin and composition of the rocks, and bear colour photomicrographs.
Source and more information: (
visit link)
=========================================================
Geopark Lichnice s tématem STAROHORY – PROTEROZOIKUM se sestává z drevostavby, ve které je instalováno pet tabulí s obecným rozvedením tématu starohory. Na nich jsou i odkazy na devet geotopu v Železných horách, kde byly zabudovány informacní tabule s odkazy na blízké fenomény souvisejícími s obdobím, ve kterém „ješte nežili trilobiti“. V okolí drevostavby jsou rozmísteny horninové bloky z území Železných hor, které zahrnují 10 dostupných ukázek ze 7 lokalit. Jedná se slabe metamorfované sedimenty, vulkanity, ruly a metabazika. Horninové bloky jsou vetšinou nalešteny a vždy opatreny pylonem s komentárem o puvodu a složení horniny, který je opatren i barevnou mikrofotografií.