During the Łate Cretaceous to Palaeogene, the Magura Basin was supplied by clastic material from source areas situated on the northern and southern margins of the basin, which do not outcrop on the surface at present. The northern source area is traditionally connected with the Silesian Ridge, whereas the position of the southern one is still under discussion. A source area situated SE of the Magura Basin supplied the Eocene pebbly para-conglomerates containing partly exotic material. The studied clastic material contains fragments of crystalline rocks, and frequent clasts of Mesozoic to Palaeogene deep and shallow-water limestones. Numerous mica schists, scarce volcanites and granitoids as well as gneisses, quartzites and cataclasites were found in the group of crystalline exotic pebbles. Monazite ages of “exotic” mica-schist pebbles from the Tylicz, Zarzecze and Piwniczna-Mniszek sections document the Variscan 310±10 Ma age of metamorphic processes. The provenance of these exotic rocks could be connected with a remote source area located SE of the Magura Basin, which could be the NW part of the Dacia Mega Unit. The idea is strongly supported by palaeotransport directions from the SE, the absence of material derived from the Pieniny Klippen Belt, the presence of shallow water limestones, typical facies of the Median Dacides belt and metamorphic age distribution proved by monazite dating.
. (2012) -Heavy min er als from Oligocene sand stones of the Menilite For ma tion of the Skole Nappe, SE Po land: a tool for prov e nance spec i fi ca tion. Geol. Quart., 56 (4): 803-820, doi: 10.7306/gq.1056Heavy min er als from sand stones be long ing mostly to the Boryslav Sand stone and Kliva Sand stone mem bers of the lower part of the Menilite For ma tion (Oligocene) in the north ern part of the Skole Nappe, Pol ish Carpathians are characterized. In the study area, the sed iments were de pos ited in the Rzeszów and Łańcut chan nel zones run ning from the north ern mar gin of the ba sin. The most fre quent heavy min er als in the sand stones ex am ined in clude zir con, tour ma line, rutile, staurolite, kyan ite and gar net. Sin gle grains of an da lu site, sillimanite, ap a tite, epidote, brookite and chrome spinel oc cur in some sam ples. The very small con tent of ap a tite is re lated to long, con tinen tal weath er ing in the source area, which is re ferred to the Pa leo zoic sed i men tary cover of the Małopolska Block and the east ern most part of the Up per Silesian Block. Dif fer ent pres er va tion states, mor phol ogy, de gree of round ness and col our va ri et ies sug gest that the heavy min er als stud ied de rive from var i ous petrographic types in clud ing meta mor phic, ig ne ous and sed i men tary rocks. How ever, the Car bon if er ous and Perm ian con glom er ates and sand stones seem to be the most prob a ble source rocks. Dorota Salata and Al fred Uchman, In sti tute of Geo log i cal Sci ences, Jagiellonian Uni ver sity,
Tour ma line pop u la tions stud ied from the Campanian-Maastrichtian part of the Ropianka (Up per Cre ta ceous-Paleocene) and Menilite (Oligocene) for ma tions of the Pol ish Carpathians, rep re sent a mix ture of first-cy cle and polycyclic grains. The tour ma lines of the de pos its stud ied dis play very strong re sem blance in terms of op ti cal fea tures and chem i cal com po si tion. They be long mostly to the schorl-dravite se ries with a mi nor con tri bu tion of tour ma lines of foititic or Mg-foititic com po si tion. Euhedral tour ma lines orig i nated from metasedimentary rocks, while the rounded grains crys tal lised in Li-poor gra nitic rocks or in pegmatites, Al-poor and Al-rich metasedimentary rocks. Most of the tour ma lines stud ied crys tal lised dur ing a sin gle igne ous or meta mor phic event. How ever, tour ma lines form ing in evolv ing chem i cal con di tions as well as polymetamorphic grains (hav ing a meta mor phic de tri tal core and meta mor phic overgrowths) are also pres ent. The chem i cal com po si tion of the meta mor phic tour ma lines stud ied in di cates their for ma tion in me dium-grade meta mor phic con di tions. This is sup ported by the crystallisation tem per a ture of the gar net-bi o tite in clu sion pres ent in one of rounded meta mor phic tour ma lines from the Ropianka For ma tion. The euhedral grains de rive from meta sedi ments, di rectly from a mas sif lo cated close to the Skole Basin. The scar city of euhedral grains in the tour ma line pop u la tions stud ied sug gests that their source rocks were poor in these min er als. The di rect sources of rounded tour ma lines (most prob a bly polycyclic grains), may have been Pa leo zoic and Me sozoic sed i men tary rocks of the Skole Ba sin fore land or crys tal line rocks of re mote source ar eas. The ini tial ig ne ous and metamor phic host rocks of the tour ma lines may have been crys tal line do mains of the Bo he mian Mas sif and/or the crys tal line base ment of Brunovistulicum.
1 In sti tute of Geo log i cal Sci ences, Jagiellonian Uni ver sity, Oleandry 2a, 30-063 Kraków, Po land Salata D. and Uchman A. (2013) Con ven tional and high-res o lu tion heavy min eral anal y ses ap plied to flysch de pos its: compar a tive prov e nance stud ies of the Ropianka (Up per Cre ta ceous-Paleocene) and Menilite (Oligocene) for ma tions (Skole Nappe, Pol ish Carpathians). Geo log i cal Quar terly, 57 (4): 649-664, doi: 10.7306/gq.1119Con ven tional and high-res o lu tion anal y ses of heavy min er als from the grav ity flow-de pos ited sand stones of the Campanian-Maastrichtian in ter val of the Ropianka (Up per Cre ta ceous-Paleocene) and Menilite (Oligocene) for ma tions of the Pol ish Carpathians dis play sim i lar com po si tions in terms of min eral spe cies. Zir con, tour ma line, rutile, gar net, staurolite and kyan ite be long to the main con stit u ents in both for ma tions. Ap a tite is com mon in the Ropianka Fm., while the Menilite Fm. al most lacks this min eral. Fur ther more, in di vid ual hornblende grains were found in the Ropianka Fm., while an da lu site is pres ent only in the Menilite Fm. The Ropianka Fm. is rel a tively richer in zir con, tour ma line, gar net and ap a tite, while the Menilite Fm. con tains more staurolite and kyan ite. Zir con and tour ma line col our and mor pho log i cal va ri et ies are sim i lar in both for ma tions. The sim i lar i ties of the heavy min eral as sem blages stud ied sug gest or i gin of these min er als from lithologically sim i lar rocks. Neg a tive cor re la tions be tween the zir con + tour ma line + rutile (ZTR) val ues and the con tent of gar net and staurolite in the Ropianka Fm. may in di cate, to a large ex tent, first-cy cle de liv ery of gar net and staurolite to the forma tion. Neg a tive, but low, cor re la tion valid only for ZTR and gar net and pos i tive cor re la tions for ZTR and staurolite and kyanite in the Menilite Fm. sug gest de liv ery of these min er als from sed i men tary rocks or/and pa limp sest sed i ments. The data ob tained on min eral re la tion ships and their mor phol ogy sug gest mixed first-cy cle and re cy cled prov e nance of the heavy miner als stud ied. Ad di tion ally, the first-cy cle ma te rial in put seems to be larger dur ing the Ropianka Fm. sed i men ta tion, while dur ing the de po si tion of Menilite Fm. the con tri bu tion of ma te rial de liv ered from ero sion of re cy cled sed i ments ap pears more prom i nent. The heavy min eral ev i dence sug gests a change at the north ern mar gin of the Skole Ba sin from an im ma ture passive mar gin with a high re lief dur ing sed i men ta tion of the Campanian-Maastrichtian part of the Ropianka Fm. to a ma ture pas sive mar gin with a low re lief dur ing sed i men ta tion of the Menilite Fm.
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