Rola mechanizmów tektonicznych w procesach powstawania złoża siarki w Machowie
Abstract
THE ROLE OF TECTONIC FACTORS IN PROCESSES OF FORMATION OF THE MACHÓW SULFUR DEPOSIT
Summary
The results of studies carried out in the Machów mine in the years 1975-1982 and interpretation of air photos made it possible to reconstruct tectonics of the deposit and succession of tectonic movements which affected Miocene strata. The studies showed three stages of tectonic movements most important for origin of the sulfur deposit include:
1) Movements from the turn of the Badenian and Sarmatian, involving antithetic rotation of block and giving rise to a system of tectonic traps for subsequently formed deposit.
2) Transcurrent movements which had taken place after the Sarniatian (after sedimentation of the Krakowiec Clays), making possible migration of hydrocarbons to previously formed traps tightly sealed with the overlaying clays.
3) Quaternary and recent movements, leading to rejuvenation of all the faults in the downthrust stress field. The movements resulted in opening of fault fissures and, therefore, made possible inflow of oxigen-rich surface waters, necessary for oxidation of H2S to sulfur.
Two systems of faults were differentiated: a) that comprising sets of N-S and W-E oriented faults, and b) that comprising sets of NW-SE and NE-SW oriented faults. Faults of the sets N-Sand NW-SE are normal, with antithetically rotated downthrown limbs, and those of the sets W-E and NE-SW - transcurrent and downthrown- transcurrent in character.
Tectonic styles of the deposit series and overlaying rocks (clays) differ due to differences in susceptibility of the rocks to deformation. The origin of folds and reversed faults in the Krakowiec Clays may be explained in terms of a horizontal compression, related to transcurrent movements along faults in the series of chemical sediments.
In the Machów mine, zones richest in sulfur are related to antithetically rotated limbs of NW-SE and N-S oriented faults and also to the neighborhood of transcurrent (NE-SW and W-E oriented) faults.
Summary
The results of studies carried out in the Machów mine in the years 1975-1982 and interpretation of air photos made it possible to reconstruct tectonics of the deposit and succession of tectonic movements which affected Miocene strata. The studies showed three stages of tectonic movements most important for origin of the sulfur deposit include:
1) Movements from the turn of the Badenian and Sarmatian, involving antithetic rotation of block and giving rise to a system of tectonic traps for subsequently formed deposit.
2) Transcurrent movements which had taken place after the Sarniatian (after sedimentation of the Krakowiec Clays), making possible migration of hydrocarbons to previously formed traps tightly sealed with the overlaying clays.
3) Quaternary and recent movements, leading to rejuvenation of all the faults in the downthrust stress field. The movements resulted in opening of fault fissures and, therefore, made possible inflow of oxigen-rich surface waters, necessary for oxidation of H2S to sulfur.
Two systems of faults were differentiated: a) that comprising sets of N-S and W-E oriented faults, and b) that comprising sets of NW-SE and NE-SW oriented faults. Faults of the sets N-Sand NW-SE are normal, with antithetically rotated downthrown limbs, and those of the sets W-E and NE-SW - transcurrent and downthrown- transcurrent in character.
Tectonic styles of the deposit series and overlaying rocks (clays) differ due to differences in susceptibility of the rocks to deformation. The origin of folds and reversed faults in the Krakowiec Clays may be explained in terms of a horizontal compression, related to transcurrent movements along faults in the series of chemical sediments.
In the Machów mine, zones richest in sulfur are related to antithetically rotated limbs of NW-SE and N-S oriented faults and also to the neighborhood of transcurrent (NE-SW and W-E oriented) faults.