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Climatic and tectonic effects on the origin and evolution of the Dereiçi travertines (the Başkale Basin, Eastern Türkiye), and neotectonic implications

Yeşilova Çetin

Geological Quarterly

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2022

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Vol. 66, No. 3

art. no. 27

EN

The Başkale Basin is located in the easternmost part of Türkiye, within a tectonically active area, and located at the intersection of Europe, Asia and the Middle East. In this study, the Dereiçi travertines, one of the most important products of neotectonism in the basin, were investigated sedimentologically, mineralogically and geochemically. To understand the neotectonic evolution of the travertine succession, the sequence was studied from bottom to top as regards morphology, lithofacies and U/Th dates. Crystalline crust, coated gas bubbles, shrub, paper-thin raft and palaeosol lithofacies have been detected in the Dereiçi travertines, which are morphologically of layer type, two ridge types and terrace type. The Dereiçi travertines commenced to precipitate at the intersection of the Işıklı and Ilıcak faults at 255.56 ±9.01 ka, and their deposition continues today. Travertine deposition paused twice between 198.31 ±18–143.07 ±1.5 ka and 96.73 ±8.34–61.59 ±5.4 ka, when palaeosol development took place. According to field and laboratory studies, the Dereiçi travertines developed under climate and tectonic control. The Işıklı and Ilıcak faults played active roles in the development of the travertines. As the travertine ages are linked to movement on both faults, the age of the Işıklı Fault should be 255.56 ±9.01 ka or earlier, and that of the Ilıcak Fault should be 143.07 ±1.5 ka or earlier.

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Reflections on the 230Th/U dating of dirty material

Geyh M. A.

Geochronometria

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2001

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Vol. 20

9-14

EN

High correlation coefficients between the activity ratios of the uranium and thorium isotopes common for the "isochron" approach of 230Th/U dating of dirty material mask the requirement to check for closed-system conditions of uranium in addition to the detrital correction of 230Th/U ages. The difficulty to calculate standard deviations of 230Th/U dates derived by the "isochron" approach complicates the problem. The methodical reasons are discussed. Closed-system conditions are checked by the 234U/ 238U - 230Th/ 238U AR plot which can also be used to carry out least-squares fitted detrital correction of 230Th/U ages of dirty material.

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Dating of the Holstejnskä Cave deposits and their role in the reconstruction of semiblind Holśtejn Valley Cenozoic history (Czech Republic)

Kadlec Jaroslav, Hercman Helena, Nowicki Tomasz, Głazek Jerzy, Vit Jan, Śroubek Pavel, Diehl Jimmy F., Granger Darryl

Geologos

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2000

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Vol. 5

57--64

EN

Large sections in cave deposits are exposed in the Holśtejnska Cave in the Moravian Karst (Czech Republic). The study of the genesis and age of these cave deposits poses a clue to the reconstruction of this cave system and of local paleohydrographic history. The time of deposition was determined by U-series dating of speleothems, 10Be and 26Al dating of quartz pebbles, radiocarbon dating of charcoal, measurement of paleomagnetic record in both clastic sediments and speleothems and by archeological evidence.