Mineralogie křemenných žil ložiska cínových rud Hřebečná u Abertam v Krušných horách (Česká republika)

An extraordinary rich mineral assemblage (more than 35 determined mineral species) has been discovered in quartz greisen mineralization found at dump material of the abandoned Mauritius mine. This mine is situated about 1 km N of the Hřebečná village, 16 km N of Karlovy Vary, Krušné hory Mountains, Czech Republic. The studied mineralization with its textural and mineralogical character differs significantly from the usual fine-grained greisens mined in this area. The primary mineralization is represented by coarse-grained quartz and fluorapatite with sporadic zircon, monazite-(Ce), xenotime-(Y) and very rare cassiterite. Besides common sulphides (arsenopyrite, chalcopyrite, pyrite, sphalerite, tetrahedrite-group minerals), Bi-sulphosalts (aikinite, bismuthinite, berryite, cuprobismutite, emplectite, wittichenite) were determined. Members of the tetrahedrite group also contain increased amounts of Bi - in addition to Bi-rich tennantite-(Zn) and tennantite-(Fe), microscopic zones represented by the not approved Bi-dominant analogue of tennantite („annivite-(Zn)“) were also found. The primary mineralization was intensively affected by supergene processes. Chalcopyrite and sphalerite are replaced by Cu sulphides - especially anilite and digenite, and more rarely by geerite, spionkopite and covellite. Some of the fluorapatite grains in the vein quartz were decomposed and mrázekite, mixite, libethenite, pseudomalachite, hydroxylpyromorphite, metatorbernite as well as rare dzhalindite crystallized in the resulting cavities. However, the most abundant supergene phases are the minerals of the alunite supergroup - crandallite, goyazite, plumbogummite, svanbergite and waylandite. The detailed descriptions, X-ray powder diffraction data, refined unit-cell parameters and quantitative chemical composition of individual studied mineral phases are presented.

Bud blight (Gemmamyces piceae) in the eastern part of the Krušné hory Mountains

A survey was carried out in 2013–2019 on the life cycle of the bud blight Gemmamyces piceae (Borthw.) Casagrande and the trend assessment in the infestation of the Colorado blue spruce Picea pungens Engelm. stands. Four ecologically different plots were chosen in the Fláje region in the Eastern part of the Krušné hory Mountains. The pycnidia were formed at the beginning of June on buds infested the previous year. Later, in the second half of June, they formed on the spring attack buds. Conidia occurred in the first week of July on the buds of the old infestation, or later in the case of the spring attack buds, in the middle of July. The production of conidia lasted till the end of September. Ascospores occurred in the middle of July and were produced until the end of September. The ability of host trees to sprout became continually weaker, along with the defoliation progress. A distinct decline in the sprouting ability was noticed on stands with a dense crown canopy and on stands with competition of broad-leaved trees – with an admixture of birch.

Monitoring of recent mass movement activity in anthropogenic slopes of the Krušné Hory Mountains (Czech Republic)

Recent mass movements currently comprise one of the main morphogenetic processes in the extensive anthropogenic relief of the foreground of the Krušné Hory Mountains in the Czech Republic. These mass movements result in several types of deep-seated slope failures, depending on the type of movement and the water saturation of the landslide material. This paper presents the results of a detailed geomorphic survey and orthophotograph analysis combined with geodetic monitoring data in an area affected by open-pit coal mining. An interdisciplinary approach has enabled an in-depth review of both the dynamics and development of recent slope failures. The article describes deep-seated landslide complex in this part of the foothills of the Krušné Hory Mountains. At the study site, mass movements occur in thick colluvial mantle and weathered Tertiary claystones. The main factors influencing their development include rainfall culminations, groundwater flowing from the valley of Šramnický Brook and former slope failures. All of the slope failures that have occurred here have originated at former slope failure sites.

Dendrogeomorphological analysis of mass movement dynamics in the Jezeří Chateau area

The object of this study is the dendrogeomorphological research of 35 severely tilted trees (Fagus sylvatica) in a natural hazard area around Jezeří Chateau in the Krušné Hory Mountains. The paper studies the dynamics of mass movement in a geologically and geomorphologically problematic area, where mining expanded high up onto the southeast-facing slopes of the Krušné Hory Mountains. Growth disturbances – eccentricities of annual rings and sudden growth changes – were examined and described for the period from 1900 to 2006. Significantly low mass movement “rates” can be observed during the 1940s and 1990s, high mass movement “rates” were identified during the first decade of the 1900s, the end of 1950s and during the 1970s.

The influence of climate effects and fluctuations in groundwater level on the stability of anthropogenic foothill slopes in the Krušné Hory Mountains, Czechia

At the beginning of the 1980s, leveling circuits Z2b 11 and Z2b 3 (later also Z2b 12) were monitored as a means of confirming the hypothesis concerning the Krušné Hory Mountains uplift. Contemporary geodetical monitoring focuses on side slopes formed by Quaternary sediments and Tertiary clystones. The stability of these anthropogenic slopes is implicated by hillside inclination, geological and geomorphological settings as well as climatic factors. The main objective of this study is to geomorphologically interpret the geodetical monitoring of the ČSA open-pit mine’s hazardous side slopes and, in addition, to prove the influence of climatic factors on slope stability.