Geochemical characteristics of ophiolitic rocks from the southern margin of the Sivas basin and their implications for the Inner Tauride Ocean, Central-Eastern Turkey

Abstract

Number of dismembered ophiolite bodies crop out between Sivas and Malatya on the top of the Eastern Tauride platform in the central-eastern Turkey. One of which at the southern margin of the Sivas basin in the Tecer Mountain area comprises melange and the lower part of an oceanic lithospheric section on top of the Tauride platform. The mantle tectonites are characterized by variably serpentinized harzburgites and dunites, and are intruded by numerous isolated dykes. The gabbroic cumulates consist of olivine gabbro, gabbro and gabbronorite. The major and trace element geochemistry of the mafic cumulate rocks suggests that the primary magma was compositionally similar to those observed in modern island-arc tholeiitic sequences. The isolated dykes are exclusively basaltic in composition and display geochemically two distinct subgroups: Group I is represented by high TiO 2 (.87-1.47 wt.%) and other incompatible elements, whereas Group II is characterized by low TiO 2 (.36-.66 wt.%) and other incompatible elements. The Group I isolated diabase dykes have flat to slightly LREE-depleted profiles (La/Yb N = .32-.79), whereas the Group II isolated diabase dykes are more depleted in general and have a LREEdepleted character (La/Yb N = .19-.49). This suggests that the isolated dykes were derived from an island arc tholeiitic magma (Nb/Y = .02-.05) with different degrees of partial melting (Group II > Group I) and relatively high oxygen fugacity in intra-oceanic subduction zone. The ophiolitic rocks in the study area may well be compared with the Divriği ophiolite to the southeast. All the evidence suggests that the isolated dykes in the Tecer Mountain area differ from the alkaline isolated dykes cutting the Divriği ophiolite. Since the late stage dykes (~76 Ma) in the Divriği area are alkaline, the tholeiitic isolated dykes in the present study should have been emplaced prior to the alkaline dykes during Late Cretaceous SSZ-spreading (~90 Ma) within the Inner Tauride Ocean.

Successive phases of serpentinization and carbonation recorded in the Sivas ophiolite (Turkey), from oceanic crust accretion to post-obduction alteration

“…We did not observe any bastites with an oblique extinction. Therefore, we propose that the protolith of the ophicalcites is harzburgite, consistent with literature (Parlak, 2016;Kavak et al, 2017).…”

The Pre‐Obduction to Post‐Obduction Evolution of the Sivas Ophiolite (Turkey) and Implications for the Precollisional History of Eastern Anatolia

“…This basin lies over the Kırşehir block to the west, the İAESZ to the north, while to the south it covers an important ophiolitic body, referred to as the Sivas ophiolite (Figure ; Guezou et al, ; Temiz, ). The evolution of this ophiolite remains poorly studied and was assigned either to the İAESZ (e.g.Poisson et al, , Temiz, ) or to the Inner Tauride Suture Zone (ITSZ; e.g., Guezou et al, ; Kavak et al, ).…”

Textural and Geochemical Properties of Tectonites in the BeyşehirHoyran Ophiolite: An Example from South of Beyşehir (Konya)

“…Dünyanın en bilinen (Troodos, Umman, Toros Ofiyolitleri vb. ) ofiyolitlerinin petrolojik ve jeokimyasal özellikleri ofiyolitlerin SSZ ortamına benzer özellikler sunduğunu göstermektedir (Robertson and Woodcock 1981 a,b;1982;Pearce et al 1984;2002;Collins and Robertson, 1997;Dilek and Whitney 1997;Dilek et al 1999;Elitok 2001;Robertson 2002;Çelik and Delaloye 2003;Parlak and Robertson 2004;Vergili and Parlak 2005;Bağcı et al 2006;Çelik, 2007;Çelik and Chiaradia 2008;Elitok and Druppel 2008;Robertson et al2013;Kavak et al 2017). Buna ek olarak, birçok SSZ ofiyolitinin yeni oluşan bir yay ortamında yitimin başlangıcından kısa bir süre sonra oluştuğu bilinmektedir (Stern and Bloomer, 1992).…”