No abstract

Coal seams in the Upper Silesian Coal Basin vanish within the Carboniferous Upper Silesian Sandstone Series and below an unconformity marking the Carboniferous top surface. Changes in the geochemical, mineralogical, petrological and palynological characteristics of gangue rocks associated with the vanished seams record what happened. The observed changes could have been caused by (1) coal-seam paleofire, (2) peat combustion, (3) igneous intrusion, (4) metasomatism and/or (5) weathering. Multifaceted research on samples collected at the Jas-Mos mining area, a part of the operating Jastrzębie-Bzie Coal Mine that are representative of different geological settings in the northern and southern parts of the mining area, point to intra-deposit paleofire as the most plausible reason for the disappearance. Biomarkers enabled recognition of differences in heating duration and oxygen access. Coal seams in the south burned quickly with abundant oxygen supply. Seams in the north pyrolyzed for an extended time under conditions of limited oxygen. Though other methods used proved less sensitive, all confirmed low (100–150 °C) paleotemperature heating. Overall, the reason for the local disappearance of the coal seams, making their exploitation difficult and unprofitable, can be assigned to a variety of different processes in a complex overlapping history of variable weathering, heating due to local endogenic fires and, probably, earlier peat combustion.

. Land slide sus cep ti bil ity map ping in the Beskid Niski Mts., West ern Carpathians (Dukla com mune, Po land). Geo log i cal Quar terly, 60 (3): 586-596, doi: 10.7306/gq.1275 Land slides are one of the most prom i nent pro cesses de grad ing the Beskidy Mts. slopes. Sus cep ti bil ity as sess ment is based on the de tailed map ping of the Dukla com mune (235 km 2 ) at the scale 1:10,000 in frames of the pro ject Land slide Coun teract ing Sys tem. The ter rain af fected by land slides is 19.59 km 2 , which is 8.34% of the re searched area. The larg est num ber of land slides can be found in the Beskid Dukielski Mts. area, where nearly 78% of all land slide ar eas are con cen trated. Anal y sis of land slide-caus ing fac tors was per formed us ing the in dex of en tropy method. The fol low ing five fac tors were con sid ered: lithol ogy, slope in cli na tion, slope as pect, dis tance to faults, and dis tance to drain age. The most im por tant role in the de vel opment of mass move ments in the study area is played by slope in cli na tion (0.0079) and li thol ogy of siliciclastic flysch (0.0066). The method ap plied also con trib uted to de vis ing a land slide sus cep ti bil ity map of con sid er able ac cu racy at 90.5%. The analy ses of the land slide fac tors have proven that un der stand ing of ge ol ogy and land forms is not only of cog ni tive sig nif i cance, but adds to prac ti cal ap pli ca tions in spa tial man age ment. The stud ies con firmed use ful ness of large-scale map ping of landslides and ap ply ing sta tis ti cal meth ods and GIS tech niques in the spa tial anal y sis of landform trans for ma tions. The ob tained land slide sus cep ti bil ity map can be a ba sis for as sess ing land slide risk. High and very high land slide sus cep ti bil ity classes cover nearly 50% of the study area.

No abstract

The deep‐seated spontaneous coal‐seam fire occurred in the southwestern part of the Upper Silesian Coal Basin (S Poland), confirmed by oxygenated compounds emission to over‐ and underlying rocks. The fire was dated at 19.2–19.8 Ma using the 39Ar‐40Ar method and palaeomagnetism. It was initiated in the Carpathian foreland thanks to a normal faulting in response to thrust‐loaded deflections of the Carpathian foreland lithosphere during collision of tectonic plates (Alcapa and stable Europe). The orogenic loading caused this normal faulting in the foreland and triggering the flexural mechanism of foredeep subsidence and forebulge uplift. Thanks to the dating of rocks affected by the spontaneous coal fire initiated during the rapid uplift of coal‐bearing rocks, when they became exposed to the aeration zone, the age of these mountain‐building processes in the Carpathians has been precisely defined.