Magnetobiostratigraphic data are presented from three Early/Middle Triassic HanBulog Limestone successions from Kqira, northern Albania. A total of 206 standard palaeomagnetic samples were obtained for thermal demagnetization and statistical analysis from the 42, 10 and 5 m thick sections. The reversal-bearing characteristic component, carried by haematite and magnetite, defines a composite sequence of six main polarity intervals (Kqln to Kq3r) in which are embedded four short polarity intervals, one at the base of Kqln and three towards the top of Kqlr. The early acquisition of the characteristic remanence is supported by the lateral correlation of magnetozones between sections. The Early/Middle Triassic boundary, approximated by the first occurrence of the conodont Chiosella timorensis, falls close to the Kqlr/Kq2n polarity transition. This is in good agreement with recently published magnetobiostratigraphic data from the coeval Chios (Greece) sections. The palaeomagnetic pole calculated from the Kqira characteristic directions lies close to the Triassic portion of the apparent polar wander path for Laurussia (in European coordinates). However, a 40-45" clockwise rotation of the external zone of the Albano-Hellenic Belt to the south of the Scutari-Pec Line is thought to have occurred since the Early-Middle Miocene. The Kqira pole acquires a West Gondwana affinity when restored for the Neogene clockwise rotation. If the clockwise rotation was entirely related to Neogene tectonics, the Kqira area was evidently associated with West Gondwana and located at 12-16"N of the western Tethys margin.
Magnetostratigraphic and biostratigraphic data for the Middle Triassic (Anisian) were obtained from the Han-Bulog facies in the Nderlysaj section from the Albanian Alps and the Dont and Bivera formations in the Dont-Monte Rite composite section from the Dolomites region of northern Italy. The Nderlysaj section is biochronologically bracketed between the late Bithynian and early Illyrian substages (i.e., late-early and early-late Anisian), whereas the Dont-Monte Rite section comprises the late Pelsonian and the early Illyrian substages. The data from Nderlysaj and Dont-Monte Rite, in conjunction with already published data, allow us to construct a nearly complete composite geomagnetic polarity sequence tied to Tethyan ammonoid and conodont biostratigraphy from the late Olenekian (late-Early Triassic) to the late Ladinian (late-Middle Triassic). New conodont data require revision of the published age of the Vlichos section (Greece).
The sedimentary succession of the Permian to Middle Triassic of the Albanian Alps is described, as part of the eastern Adria passive margin towards the Tethys. A carbonate ramp deepening towards NE in present day coordinates developed during the Middle Permian and was affected by block faulting with the deposition of carbonate breccia. The Early Triassic was characterized by intense terrigenous deposition with several cobble conglomerate units up to 80 m-thick, and by oolitic carbonate shoals. The fine clastic deposition ended gradually during the earliest Anisian and a wide calcarenitic ramp occupied the area, with small local carbonate mounds. Basinward, the red nodular limestone of the Han Bulog Formation was interbedded with calcarenitic material exported from the ramp. Drowning to more open conditions occurred towards the end of the Pelsonian. Subsequently, cherty limestone and tuffitic layers spread over the entire area. Towards the end of the Ladinian, with the end of the volcanic activity, red pelagic limestone was deposited locally for a short period. By the latest Ladinian most of the area returned to shallow-water conditions, with a peritidal carbonate platform. In the Theth area, in contrast, a basin with black organic-rich dolostone and limestone developed which seems to be unique in that part of the Adria passive margin. The occurrence of cobble conglomerate units in the Lower Triassic testifies to very active block faulting and high accommodation, not yet described for the area.
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