Source rock characteristics and biostratigraphy of the Lower Silurian (Telychian) organic-rich shales at Akyaka, central Taurus region, Turkey

Varol, Osman; Demirel, İsmail Hakkı; Rickards, R. B.; Günay, Y.

doi:10.1016/j.marpetgeo.2006.07.003

Cited by 14 publications

(3 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lower Paleozoic graptolite-bearing rocks were mainly deposited in marine environments, and are important source rocks globally, especially shale gas deposits in the Wufeng-Longmaxi (also known as Wufeng-Lungmachi) sediments from China (Zou et al, 2010;Zou et al, 2012;Dai et al, 2014;Luo et al, 2016;Zou et al, 2016;Luo et al, 2017;Luo et al, 2018). These organic matter (OM)-rich facies were also identified as true or potential hydrocarbon source rocks in the Anadarko basin in the USA (Wang and Philp, 1997), North Africa and Arabian Peninsula (Jones and Stump, 1999;Lüning et al, 2000), Taurus region of Turkey (Varol et al, 2006), the Czech Republic (Suchý et al, 2002), and the Siberian platform (Makarov and Bazhenova, 1981). More recently, such shales have been recognized as potential targets for unconventional shale gas deposits in the Norwegian-Danish Basin (Schovsbo et al 2011(Schovsbo et al , 2014Pool et al 2012), and Baltic basin of Central Europe (Littke et al, 2011;Karcz et al, 2013;Yang et al 2017).…”

Section: Introduction and Previous Studiesmentioning

confidence: 99%

Graptolites as fossil geo-thermometers and source material of hydrocarbons: An overview of four decades of progress

Luo

Goodarzi²,

Zhong

et al. 2020

Earth-Science Reviews

View full text Add to dashboard Cite

Section: Introduction and Previous Studiesmentioning

confidence: 99%

Graptolites as fossil geo-thermometers and source material of hydrocarbons: An overview of four decades of progress

Luo

Goodarzi²,

Zhong

et al. 2020

Earth-Science Reviews

View full text Add to dashboard Cite

“…The deposition of the black shales with some lydite bands could also be related to the middle shelf environment. These sediments build up the lower part of the Bozyazı-Tekmen section in the southern Central Taurides and the Korudağ section in the SE Anatolian Autochthon (Varol et al, 2006;Kozlu et al, 2012a). The lydite-dominated succession, on the other hand, that occurs in the sections of the Geyikdağ Unit of the E Taurides is considered as deposited in shelf-edge zones.…”

Section: Late Hirnantian-earliest Ludlow (Figure 9b)mentioning

confidence: 99%

Thuringian affinity of the Silurian–Lower Devonian succession from the Eastern Taurus, Turkey

Sachanski¹,

Kozlu²,

Göncüoğlu³

2015

Turkish J Earth Sci

View full text Add to dashboard Cite

Lederschiefer Formation grades conformably into graptolitic shales with chert beds from the lower part of the Lower Graptolite Shale Formation (25-30 m; from Akidograptus ascensus to Oktavites spiralis biozones). This alternation grades upwards into black shales of the upper unit of the formation (8-10 m; from Oktavites spiralis to Neodiversograptus nilssoni biozones). Phosphate concretions are common and usually concentrated at certain levels. The Ockerkalk Formation (15-50 m; from Lobograptus progenitor to Istrograptus transgrediens biozones) consists of platy to thick-bedded limestones and intercalated thin shale layers. Orthocone nautiloids occur in the lower part of the formation while for the Abstract: The Silurian-Lower Devonian succession in the Değirmentaş-Halevikdere section (E Taurides) shows considerable lithostratigraphic similarities to the three-partite subdivision, initially documented in the same stratigraphic interval in Saxo-Thuringia and later in other peri-Gondwanan terrains. The Llandovery-Wenlockian part of the studied section (ca. 40 m) is characterized by black graptolitic shales. The Llandoverian part is dominated by radiolarian ribbon cherts (ca. 20 m). The Rhuddanian Akidograptus ascensus, Parakidograptus acuminatus, and Cystograptus vesiculosus biozones have been recognized in its lower part, while in the upper part of the succession, the lowermost Telychian Rastrites linnaei Biozone has been documented. The Telychian Spirograptus turriculatus and Streptograptus crispus biozones, as well as the Sheinwoodian Cyrtograptus rigidus/Monograptus belophorus Biozone, have been identified within this succession. Graptolites of the Homerian (Colonograptus deubeli + Col. praedeubeli and Col. ludensis biozones) are only found in the Pekmezköy and Gürleşen areas, in the black shales, immediately before the first ocher-colored limestone, which is characteristic for the Ockerkalk Formation in the Thuringian facies. The dominantly ocher-colored shale-limestone alternation in the Değirmentaş-Halevikdere section is ca. 50 m in thickness. The lower Ludlowian part is enriched by nautiloids, while in the Pridolian part crinoids are abundant. It is covered by 60-m-thick black shales and siltstones, corresponding to the Upper Graptolite Shale Formation in the Thuringian. The Silurian-Devonian boundary is located in the lower part of this unit on the basis of lobolith findings. The depositional model proposed here accounts for the migration of the considered peri-Gondwana terrains from high to low paleogeographic latitudes that has triggered changes not only in the ocean water thermohaline circulation but also in the wind-driven downwelling or upwelling systems. These changes are responsible for the progressive transition from an oxic regime to an anoxic one in the deep oceanic depositional environments (outer continental shelf, slope, and ocean basin settings) and the deposition of light and dark sediments there.

show abstract

“…and ends in reefal limestones of the Upper Miocene Mut Formation and Quaternary alluvium deposits. Following a regional uplift and glaciation in the Late Ordovician (Göncüoglu and Kozlu, 2000), the second phase of sedimentation begins with uppermost Ordovician units (the lower unit of Monod et al [2003], consisting of sandstones of fluvial to shallow marine origin, is followed by Silurian transgressive sediments (Egripınar and Hırmanlı formations of Demirtaşlı [1983] composed by dark grey limestone and black shales rich in both graptolites and organic matter [Varol et al, 2006]). …”

Section: Depositional History and Stratigraphymentioning

confidence: 99%

Hydrocarbon Source Rock Assessments of the Late Jurassic Black Shales (Tokmar Formation) in the Central Taurus Region of Turkey

Oyal¹,

Yurtsever

Demirel

2010

Petroleum Science and Technology

View full text Add to dashboard Cite

The hydrocarbon source rock potential and the thermal maturity of the Late Jurassic Tokmar Formation in the Boguntu area of the central Taurus region have been investigated. Tokmar Formation includes organic matter-rich dark grey shales alternating with carbonates that were deposited under dysoxic to anoxic marine conditions prevailed in the Late Jurassic. A total of 14 samples have been analyzed by Leco and Rock-Eval pyrolysis for determination of their hydrocarbon source rock characteristics and organic maturity. The total organic carbon content of the samples range from 0.26 to 1.53 wt%. The actual Rock-Eval pyrolytic yields (S 1 C S 2 peak values) are between 0.25 and 3.63 mg HC/g rock. The calculated hydrogen index and oxygen index values imply that the main organic matter types are Type II and Type III kerogens. T max versus hydrogen index values indicate that the Boguntu samples are thermally mature and took place in the oil generation window.

show abstract

Source rock characteristics and biostratigraphy of the Lower Silurian (Telychian) organic-rich shales at Akyaka, central Taurus region, Turkey

Cited by 14 publications

References 50 publications

Graptolites as fossil geo-thermometers and source material of hydrocarbons: An overview of four decades of progress

Graptolites as fossil geo-thermometers and source material of hydrocarbons: An overview of four decades of progress

Thuringian affinity of the Silurian–Lower Devonian succession from the Eastern Taurus, Turkey

Hydrocarbon Source Rock Assessments of the Late Jurassic Black Shales (Tokmar Formation) in the Central Taurus Region of Turkey

Contact Info

Product

Resources

About