The İstanbul–Zonguldak Tectonic Unit, which is devoid of Devonian–Carboniferous magmatism, is a continental fragment of Far East Avalonia. It was deformed by thrusting due to the collision with the Sakarya terrane with Minoa origin during the Carboniferous, and forms the Variscan foreland. The tectono-magmatic evolution of Devonian–Carboniferous, thus consumption evolution of the Rheic Ocean in Far East Avalonia, is poorly known. Diabase and basaltic andesite dykes show Late Devonian to Late Carboniferous igneous crystallization ages in the İstanbul–Zonguldak Tectonic Unit (NW Turkey). They have aphanitic to vitrophyric textures. U–Pb dating on igneous zircons from diabase and basaltic andesite dykes yielded Late Devonian age of ca. 381.3 ± 1.8 Ma (2σ) and Late Carboniferous ages of ca. 306.1 ± 3.3 to 301.5 ± 1.1 Ma (2σ), respectively. Geochemically, Late Devonian magmatism shows tholeiitic affinities and contains subduction and with-in plate components, but Late Carboniferous magmatism displays calc–alkaline signatures and includes subduction components. The Late Devonian dykes intruded into the continental block during the rifting of the Pripyat–Dnieper–Donets Basin in Baltica as a result of the north-subducting Rheic Ocean. While it proceeded to subduct under Far East Avalonia along the magmatic arc that was similar to the Hanseatic arc in East Avalonia, Late Carboniferous dykes emplaced into it in an arc-related setting. Also, Late Carboniferous magmatism that is related to magmatic arc displays that the collision of the İstanbul–Zonguldak Tectonic Unit and Sakarya terrane, described as the Variscan orogeny in the Pontides did not form during the Carboniferous.

不含泥盆纪-石炭纪岩浆作用的伊斯坦布尔-宗古尔达克构造单元是远东阿瓦隆大陆的一部分。在石炭纪期间，由于与具有Minoa起源的Sakarya地相的碰撞而使冲断作用变形，并形成了Variscan前陆。泥盆纪-石炭纪的构造-岩浆演化，即远东阿瓦隆地区的变质海的消费演化，是鲜为人知的。辉绿岩和玄武质安山岩岩脉在伊斯坦布尔–宗古尔达克构造单元（土耳其西北部）显示出晚泥盆世至石炭纪晚期的火成岩时代。它们具有仿生至玻璃质的质地。辉绿岩和辉绿岩和玄武质安山岩脉上的锆石的U–Pb年代大约为泥盆纪晚期。381.3±1.8 Ma（2σ）和大约石炭纪晚期。306.1±3.3至301.5±1.1 Ma（2σ）。从地球化学上看，晚泥盆世岩浆作用表现为高亲和力，包含俯冲和板内成分，但晚期石炭纪岩浆表现出钙-碱性特征，并包括俯冲成分。由于北俯冲的大洋，在波罗的海的普里皮亚季-第聂伯-顿涅茨盆地裂陷期间，泥盆纪晚期堤防侵入了大陆块。当它沿着与东阿瓦隆地区的汉萨同化弧类似的岩浆弧在远东阿瓦隆地区下俯冲时，晚石炭纪脉石在一个与弧有关的环境中被置入其中。同样，与岩浆弧有关的晚石炭纪岩浆活动表明，在石炭纪期间并未形成伊斯坦布尔－宗古尔达克构造单元和萨卡里亚地体的碰撞，这被称为庞德的瓦里斯坎造山运动。泥盆纪晚期岩浆活动显示出亲缘关系，并包含俯冲和板内成分，但石炭纪晚期岩浆活动显示钙-碱性特征，并包括俯冲成分。由于北俯冲的大洋，波罗的海的普里皮亚季-第聂伯-顿涅茨盆地发生裂陷时，泥盆纪晚期堤防侵入了大陆块。当它沿着与东阿瓦隆地区的汉萨同化弧类似的岩浆弧在远东阿瓦隆地区下俯冲时，晚石炭纪脉石在一个与弧有关的环境中被置入其中。同样，与岩浆弧有关的晚石炭纪岩浆活动表明，在石炭纪期间并未形成伊斯坦布尔－宗古尔达克构造单元和萨卡里亚地体的碰撞，这被称为庞德的瓦里斯坎造山运动。泥盆纪晚期岩浆活动显示出亲缘关系，并包含俯冲和板内成分，但石炭纪晚期岩浆活动显示钙-碱性特征，并包括俯冲成分。由于北俯冲的大洋，在波罗的海的普里皮亚季-第聂伯-顿涅茨盆地裂陷期间，泥盆纪晚期堤防侵入了大陆块。当它沿着与东阿瓦隆地区的汉萨同化弧类似的岩浆弧在远东阿瓦隆地区下俯冲时，晚石炭纪脉石在一个与弧有关的环境中被置入其中。同样，与岩浆弧有关的晚石炭纪岩浆活动表明，在石炭纪期间并未形成伊斯坦布尔－宗古尔达克构造单元和萨卡里亚地体的碰撞，这被称为庞德的瓦里斯坎造山运动。