J. (2012) -Prov e nance of Up per Cre ta ceous quartz-rich sand stones from the North Sudetic Synclinorium, SW Po land: constraints from de tri tal tour ma line. Geol. Quart., 56 (2): 315-332, doi: 10.7306/gq.1024Up per Cre ta ceous quartz arenites that fill the North Sudetic Synclinorium on the north ern pe riph ery of the Variscan Bo he mian Mas sif show high compositional but low tex tural ma tu rity. They have been in ter preted for years as de rived largely from nearby gran ite plutons, i.e. as first-cy cle sed i ments. A dif fer ent prov e nance was re vealed on the ba sis of a com bined light and heavy min eral anal y sis, and par ticu larly a de tri tal tour ma line study, given that tour ma line is a sen si tive in di ca tor of gra nitic/meta mor phic/sed i men tary (multi-re cy cling) or i gin. Cenomanian, Turonian, Coniacian and Santonian sand stones con tain abun dant an gu lar tour ma line grains, to gether with zir con and rutile, and subordinately staurolite, gar net, ana tase, kyan ite, sillimanite and monazite. The suc ces sive -Cenomanian to Santoniantour ma line pop u la tions are sim i lar with re gard to shape, col our and chem i cal com po si tion. The lat ter points un am big u ously to var i ous meta mor phic rocks with a pre dom i nant group of Al-rich metapelites (Al-rich, F-poor dravite). It is con cluded that, in the Late Cre taceous, large Sudetic gran ite plutons such as the Karkonosze and Strzegom-Sobótka mas sifs were not ex posed but were bur ied un der a thick siliciclastic cover. These re sults cou pled with pub lished ap a tite fis sion-track data from the gra nitic Karkonosze Pluton and the gneissic/migmatitic Góry Sowie Mas sif re veal that Late Cre ta ceous quartz arenites of the North Sudetic Synclinorium re flect grad ual exhu ma tion of the sur round ing mas sifs, but do not re cord the fi nal ex po sure of crys tal line rocks. Since the lat est Turonian, this ex hu ma tion cor re sponded to the Late Cre ta ceous in ver sion ep i sode in Cen tral Eu rope. The tex tural im ma tu rity of Up per Cre ta ceous sand stones is mis lead ing in terms of their re cy cled or i gin, and it is in her ited from im ma ture clastic source rocks.
AB ST R ACT : Sudoite, an aluminium-rich di-trioctahedral chlorite, is known primarily from highgrade diagenetic/ low-temperature metamorphic Al-rich rocks and from hydrothermal deposits in Alrich terrains. This contribution reports a rare occurrence of pore-lining sudoite in Permian red beds from the eastern part of the Southern Permian Basin. Sudoite is a ubiquitous mineral in aeolian sandstones of the Eastern Erg, a large dune field buried in the subsurface of the Fore-Sudetic Monocline, SW Poland. Sudoite crystals are arranged in a honeycomb texture and often associated with high-porosity intervals. It is concluded that sudoite crystallized at the expense of early diagenetic dioctahedral smectite at a temperature lower than 180ºC under the influence of hot, Mgrich and K-poor fluids, which migrated from a basement and/or deep part of the basin upward through permeable aeolian sandstones and mixed with colder pore solutions. Tosudite was a likely intermediate phase in the smectite to sudoite conversion.
Biernacka, J., 2015. What can be learned from the K-Ar ages of illite from Rotliegend sand stones of the Fore-Sudetic Monocline, SW Po land? Geo log i cal Quar terly, 59 (2): 257-270, doi: 10.7306/gq.1210The avail able K-Ar ages of authigenic illite from Rotliegend ae olian sand stones of the Fore-Sudetic Monocline, SW Po land, in clud ing those from six sam ples ex am ined in the pres ent study, are crit i cally re viewed in terms of their geo log i cal mean ing and com pared with the K-Ar ages of illite from the re main ing part of the South ern Perm ian Ba sin in Europe. The ma jor ity of ages fall in the range be tween 195 and 150 Ma, i.e. they cor re spond to Ju ras sic times. The re sults may be grouped in sev eral time in ter vals, which are al most iden ti cal to those iden ti fied for Rotliegend sand stones of Cen tral and West ern Eu rope, and which are ten ta tively in ter preted as pulses of in tense illite growth. Short-last ing illitisation is re corded only at places. More often, illitisation pro ceeded as a multi-stage pro cess, which in the north ern part of the Fore-Sudetic Monocline might have lasted un til the Cre ta ceous. The K-Ar ages of authigenic illite gen er ally co in cide with the mod elled time of gas gen er a tion from Car bon if er ous rocks and the fill ing of res er voirs in the area of the Fore-Sudetic Monocline. Pos si bly, the same un der lying pro cesses trig gered illitisation and hy dro car bon ex pul sion, or hy dro car bon mi gra tions trig gered fluid flows and illite crystallisation.
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