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Micropalentological Analysis And Sequence Stratigraphy Through Upper Tournaisian Substage In Aladag Unit (central Taurides, Turkey)Dinc, Aksel Tugba 01 December 2009 (has links) (PDF)
The purpose of this study is to investigate the Upper Tournaisian substage within the Carboniferous carbonate deposits of the Aladag Unit in the Hadim region (Central Taurides) based on foraminiferal diversity and to study the meter scale
cyclicity in order to explain the sequence stratigraphic evolution of the carbonate
succession.
In this study, a 27.01 m thick stratigraphic section consisting of limestones and
shales was measured and 89 samples, collected along this section, were analyzed.
Micropaleontological analyses are based on benthic foraminifera. According to
the benthic foraminiferal assemblages, two biozones were identified as Zone Ut1
and Zone Ut2 within the Upper Tournaisian. Zone Ut1 is characterized by a poor
foraminiferal assemblage while the Zone Ut2 consists of a diverse Upper
Tournaisian foraminiferal fauna.
In order to construct a sequence stratigraphic framework and appreciate
depositional environmental changes, microfacies studies were carried out. Seven
microfacies types were recognized and depending on the stacking patterns of these
microfacies types, two fundamental types of cycles, A and B, were identified.
Through the measured section, twenty-five shallowing-upward meter scale cycles and two sequence boundaries were determined. Quantitative analysis of benthic
foraminifera was used to demonstrate the biological response to cyclicity. Since
foraminifers are very sensitive to sea level changes, the abundance of benthic
foraminifera displays a good response to sedimentary cyclicity.
In order to apply a worldwide sequence stratigraphic correlation, the sequence
boundaries and the meter scale cycles of this study were compared with those
described in South China and Western European platform and the Moscow
Syneclise. An Early Tournaisian transgression was followed by a major fall in
relative sea level during the Late Tournaisian. Two sequence boundaries
recognized in the measured section correspond to global sea level falls in the Late
Tournaisian.
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Micropaleontological Analysis And Facies Evolution Across The Tournaisian-visean Boundary In Aladag Unit (central Taurides, Turkey)Peynircioglu, Ahmet Ali 01 December 2005 (has links) (PDF)
This study aims to enlighten microfacies evolution and micropaleontological properties of the Tournaisian & / #8211 / Visean boundary in Aladag Unit (Central Taurides, Turkey). Two sections comprising dark shale and dark limestone alternations, including a fairly dolomitized part towards their top are measured. The microfacies analysis suggests a subtidal depositional environment.
Foraminiferal assemblages were distinguished at Section AP and biozonation was documented. The biozonation separates the measured section into three zones, described as A, B and C. Zone A is scarce foraminifera fauna, and mainly contains Earlandia sp. Zone B is defined by appearance of a diversified foraminifera fauna and the first appearance of Lugtonia monilis (Malakhova, 1955) with Eoparastaffella sp. (morphotype 1). Zone C is defined according to the first appearance of Eoparastaffella simplex (Vdovenko, 1964) (morphotype 2) and foraminifers Laxaendothyra ex. gr. laxa. Tournaisian & / #8211 / Visean boundary is defined at the 60th sample, due to appearance of Eoparastaffella simplex (Vdovenko, 1964) (morphotype 2).
Seven microfacies types in section AP, and six microfacies types in section PA are identified and, the intensely sampled part of the measured section AP is separated into 13 shallowing upward meter-scale cycles. These cycles, showing
subtidal character are detected by both repetitions of microfacies and changes in abundance of foraminifers.
A contrasting evaluation of the Tournaisian & / #8211 / Visean boundary of Taurides with Guangxi, South China and Dinant, Belgium is presented. The Chinese stratotype contains a diverse, more complete fauna of Tournaisian - Visean foraminifera, while the Belgium and Turkish sections are scarcer and most probably facies controlled.
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Chondrichthyan Diversity within the Burlington-Keokuk Fish Bed of Southeast Iowa and Northwest Illinois (Mississippian: Osagean)Hoenig, Matthew Michael James 17 December 2019 (has links)
No description available.
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