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This paper describes the occurrence of dolostone and the mechanism of dolomitization of the Upper Devonian Golbogazi Formation in the allochthonous Taurus Mountains Aladag unit in Turkey. The Upper Devonian Golbogazi Formation carbonates, with dominant ostracod-bearing mudstone and wackestone, formed tidal and subtidal environments, and some of these rocks were dolomitized from shallow to deep burial. On the basis of the field, the petrographic and geochemical features, four different replaceable and cement dolostone phases have been recognized. The replacive dolostones contain (1) very fine to fine crystalline planar-s dolostone (df1), (2) medium to coarse crystalline planar-s to planar-e dolostone (df2), (3) coarse to very coarse crystalline non-planar-a dolostone (df3), and (4) coarse to very coarse crystalline planar dolostone cement (df4). The replacive dolostones are disordered to moderate the ordered and calcium-rich. They are non-stoichiometric and have 46–59 mol% CaCO3 and 41–54 mol% MgCO3 total contents. The df1 dolostones have MgCO3 contents of 41–54 mol%, the df2 dolostones have 41–53 mol%, the df3 dolostones have 49 mol%, and the df4 dolostones have 49–50 mol%, respectively. The Golbogazi dolostones have δ18O values of −9.44 to −2.20‰ Vienna Pee Dee Belemnite (VPDB) and δ13C values of −1.58 to +2.52 VPDB. Sr, Na, Mn, and Fe concentrations of replacive dolostones are 74–184, 148–593, below detection level (bdl)–619, and 1049–9233 ppm, respectively. The petrographic and geochemical data demonstrate that the replacive dolostones occurred prior to the chemical compaction at shallow to intermediate burial depths from Late Devonian seawater and/or seawater lightly modified by water–rock interaction process and later recrystallized by basinal brines at increasing burial depths and temperature. The North American Shale Composite-normalized rare earth element values of both limestone and dolostone show very similar rare earth element patterns characterized by slightly or considerably negative cerium (Ce) anomalies and a clear depletion in all rare earth element species. The dedolomitization observed in the Golbogazi Formation is thought to occur by the oxidizing effect of the meteoric water in the shallow burial environment during the telodiagenesis.

Calisma alanindaki stratigrafik istif mermer ve sistten ibaret Karbonifer-Triyas yasli Malatya metamorfikleri ile baslar ve Maastrihtiyen yasli Gunduzbey grubu tarafindan uyumsuzlukla ortulur. Gunduzbey grubu, konglomera ve kumtasindan olusan Kizilguney formasyonu ile turbiditik kumtasi arakatkili kirectasi-marn ardalanmasindan olusan Kapullu formasyonundan ibarettir. Istif, Kapullu formasyonunu uyumsuzlukla orten Zorbon, Yukaribanazi ve Gedik formasyonlarini iceren Lutesiyen yasli Yesilyurt grubu ile devam eder. Zorbon formasyonu konglomera aratabakali kumtasi ve camurtasindan olusurken, Yukaribanazi formasyonu olistolit ve konglomera arakatkili kumtasi-seyl ardalanmasindan olusmaktadir. Gedik formasyonu resifal kirectasi, kiltasi ve marndan ibarettir ve kumtasi aratabakali Pliyosen yasli Beylerderesi formasyonu tarafindan uyumsuzlukla ustlenir. Kuvaterner yasli aluvyon bolgedeki kendisinden yasli butun birimleri uyumsuz olarak orter. Gedik formasyonunda sacinimli olarak erken dolomitlesme gelismistir.

This paper describes the occurrence of dolomite and the mechanism of dolomitization of the Upper Triassic-Lower Jurassic Kiziloren Formation in the autochthonous Bolkardagi unit of the middle Taurus Mountains in south western Turkey. Dolomites were analyzed for geochemical, isotopic and crystallographic variation. Dolomites occur as a replacement of precursor carbonate and cement. The dolomite crystals range from

An integrated petrographic and geochemical study of the sandstones of the Maastrichtianaged in the Orhaniye (Kazan-Ankara-Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting. Depending on their matrix and mineralogical content, the Maastrichtian sandstones are identified as lithic arenite/wacke. The Dikmendede sandstones derived from types of provenances, the recycled orogen and recycled transitional. The chemical characteristics of the Dikmendede sandstones, i.e., fairly uniform compositions, high Th/U ratios (>3.0), negative Eu anomalies (Eu/Eu* 0.72–0.99) and Th/Sc ratios (mostly less than 1.0), favor the OUC (old upper continental crust) provenance for the Dikmendede sandstones. The SiO2/Al2O3, Th/Sc (mostly

The objective of this study is to determine the sedimentary properties of dolomites in terms of petrography and geochemistry, which belong to the Dedebeleni (Jurassic) formation existing at the surroundings of Beyreli Village of Hadim District lying at the southeast of Konya City. Jurassic-aged Dedebeleni formation, locating Central Taurus composed of limestone, mudstone, dolomitic limestone and dolomite. Dedebeleni formation microfacies: wackestone, packstone, crystalline limestone and dolosparite.The Sr content in the Dedebeleni formation (73 to 88 ppm in the early dolomites, and 58 to 77 ppm in the late dolomites, respectively) are compatible with the Sr concentration shallow-deep burial dolomites. The Na content in the Dedebeleni formation (148 ppm in the early dolomites, and 74 to 148 ppm in the late dolomites, respectively) are compatible with the Na concentration shallow-deep burial dolomites. The investigated dolomites suggest to occur from normal sea water or weakly evaporative sea water δO18 compositions (‰ -2,37 to -3,35) in the early diagenetic dolomites of Dedebeleni formation. The δO18 compositions (‰ -4,39 to -5,9) of late diagenetic dolomites in the Dedebeleni formation propose to occur from basinal brines at elevated temperatures. The δC13 values (early dolomites: ‰ +1,29 ile +2,65; late dolomites: ‰ +0,79 ile +3,14) in the dolomites of Dedebeleni formation stress to occur biogenic and non-biogenic. As a result, the Dedebeleni formation dolomites have been formed as early diagenetic at the shallow-burial environment and as the late diagenetic at the medium burial environment, Bu çalışmanın amacı Konya güneybatısındaki Hadim ilçesinin Beyreli Köyü çevresinde yer alan Dedebeleni formasyonuna (Jura) ait dolomitlerin petrografik ve jeokimyasal bakımdan sedimanter özelliklerinin belirlenmesine yöneliktir. Orta Toroslarda bulunan Jura yaşlı Dedebeleni formasyonu kireçtaşı, çamurtaşı, dolomitik kireçtaşı ve dolomitten oluşmaktadır. Dedebeleni formasyonu mikrofasiyesi: vaketaşı, istiftaşı, kristalin kireçtaşı ve dolosparit şeklindedir. Dedebeleni formasyonu Sr içeriği (erken dolomitler 73-88 ppm ve geç dolomitler 58-77 ppm) sığ ve derin gömülme dolomitleriyle tutarlıdır. Yine, Dedebeleni formasyonu Na içeriği (erken dolomitler 148 ppm ve geç dolomitler 74-148 ppm) de sığ ve derin gömülme dolomitleriyle tutarlıdır. Dedebeleni formasyonu erken diyajenetik dolomitlerinin δO18 izotopik bileşimleri ‰ -2,37 ile -3,35 normal deniz suyu ya da evaporatif hafif konsantre (yoğun) deniz suyundan oluşumu önermektedir. Geç diyajenetik dolomitlerin izotopik bileşimleri ise ‰ -4,39 ile -5,9 yükseltilmiş sıcaklıklarda havzasal tuzlu sulardan oluşumu önermektedir. Dedebeleni formasyonu dolomitlerindeki δC13 değerleri erken diyajenetik; ‰ +1,29 ile +2,65; geç diyajenetik; ‰ +0,79 ile +3,14 biyojenik ve non-biyojenik kaynağı ifade etmektedir. Sonuç olarak Dedebeleni formasyonuna ait dolomitler sığ gömülme ortamında erken diyajenetik ve orta gömülme ortamında geç diyajenetik olarak oluşmuştur.

The stratigraphic sequence in the Beykoyu-GokceyazI area, central Turkey, starts with the Palaeocene–lower Eocene Guneydagi Formation, including limestone interbedded with calcirudite, calcarenite, and marl. An angular unconformity separates the unit from the overlying Beykoyu Formation, which has two members: Kabaktepe gypsum and Kayalidagtepe stromatolitic limestone. A Miocene lacustrine environment is inferred for the deposition of the Beykoyu Formation, based on the existence of blue-green algae (Schizothrix sp., Scytonema sp., and Phormidium sp.) as well as green algae (Chara sp.), lacustrine Gastropoda (Planorbarius sp.), and lacustrine ostracodes. The sequence continues with the upper Pliocene–Holocene Kuskuncuk Formation, containing alternations of conglomerate, sandstone, and mudstone, with caliche bands in some levels, which were deposited in alluvial fan and braided stream environments. Quaternary alluvium is the youngest unit in the sequence.

The stratigraphic sequence in the study area starts with the Carboniferous–Triassic Malatya Metamorphics, which are composed of marble and schist and covered unconformably by the Maastrichtian Gunduzbey Group. The group includes the Kizilguney Formation with conglomerate and sandstones, and the Kapullu Formation containing limestone–marl alternations, with turbiditic sandstone intercalations. The sequence continues with the Lutetian Yesilyurt Group, which includes the Zorbon, Yukaribanazi, and Gedik Formations, unconformably overlying the Kapullu Formation. The Zorbon Formation is composed of conglomerate interbedded with sandstone and mudstone, whereas the Yukaribanazi Formation consists of sandstone and shale alternations with intercalations of conglomerates and olistoliths. The Gedik Formation is composed of reefal limestone, claystone, and marl, and underlies the Pliocene–Quaternary Beylerderesi Formation formed of conglomerate interbedded with sandstone. Holocene alluvium unconformably overlies all units in the region.