Palaeogeography of the NW and central part of the Miechów Depression during the Jurassic as a result of the palaeotectonics development

• Autorzy: Złonkiewicz Z.
• Konferencja: International Congress on the Jurassic System (7 ; 06-18.09.2006 ; Kraków, Poland)
• Języki publikacji: EN

Abstrakty

EN

The Variscan movements elevated mountain ranges and uplands, forming vast massifs along the East European Craton. The structurally complicated Małopolska Massif was located in SE Poland. In the Jurassic the area corresponding to the Laramide Miechów Depression was located on the SW periphery of the Mid-Polish Trough and N periphery of the Tethys. The palaeogeographic development of the area of study was affected by reactivation of Caledonian-Variscan structures in the pre-Permian basement. It may be detected the influence of the Włoszczowa Massif (NW part of the Małopolska M.) as an area of a lesser subsidence. The Pilica Fault (on the NW Włoszczowa Massif edge) limited the pre-Bathonian transgressions to the SE part of the area of study. Also a narrow gulf/graben or isolated basin was temporarily formed in the Lasocin-Strzelce Dislocation Zone at the border of the Holy Cross Mts. and the area of study. Alluvial, deltaic and lagoonal to medium siliciclastic shelf sediments were deposited. Since the Bajocian an inland basin, elongated W-E, was formed parallel to the S border of the Włoszczowa Massif and in the Bathonian an ingression from SE began. Narrow gulfs/grabens and submarine ridges/horsts NNW-SSE elongated formed in the central part of the area of study. They continued further southwards up to the present edge of the Carpathians. By the end of the Middle Jurassic, lagoonal to distal siliciclastic shelf deposits corresponded to several transgression-regression cycles, interrupted by local erosion. The marine deposits of an open carbonate shelf of the Callovian - Early Kimmeridgian cycle covered the area of study and a local zone of maximal subsidence in the Jurassic was formed. The facies zones of various sponge-detrital deposits, mudstones and marls in its NW and central part were elongated NW-SE, and in the SE part they changed their direction to WNW-ESE. The fractioned Włoszczowa Massif subsided within grabens in the extending Lasocin-Strzelce Dislocation Z. The local subsidence zone, crossed the Włoszczowa Massif. It penetrated and deepened further in SE directionin the basin of Carpathian Foreland. The Late Oxfordian and Early Kimmeridgian regression resulted in temporal formation of a shallow water carbonate platform. It passed over the Mid-Polish Trough, migrating southwards, and the fine-grained shoal deposits and oolitic barriers reached, but did not crossed, the area of study. The shallowest facies of the platform, located SW to the Holy Cross Mts., was underlain by the northern element of the Włoszczowa Massif. A narrow zone of deeper marly facies, still preserved, split the carbonate platform. That pattern might be detected also in deposition of marls and lumachelles of the following transgression, which commenced in the Kimmeridgian between the Hypselocyclum and Divisum chrons.

Słowa kluczowe

EN

Miechów Depression; Włoszczowa Massif; Lasocin-Strzelce Dislocation Zone; palaeogeography; palaeotectonics

• Wydawca: Państwowy Instytut Geologiczny - Państwowy Instytut Badawczy
• Czasopismo: Volumina Jurassica
• Rocznik: 2006
• Tom: Vol. 4, no. 1
• Strony: 72--72

Twórcy

autor

Złonkiewicz Z.

• Polish Geological Institute, Holy Cross Branch, ul. Zgoda 21, PL-25953 Kielce, Poland,