Petrochemistry and age of garnet-bearing xenoliths and their host volcanic rocks of Central Anatolia, Turkey: Implications for the evolution of magma-hydrothermal systems

IF 2.6 3区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Chemie Der Erde-Geochemistry Pub Date : 2024-11-01 DOI:10.1016/j.chemer.2024.126165

Aslıhan Korkmaz Eryılmaz , Elif Varol , G. Deniz Doğan-Külahcı , Sibel Erkül , Chris Harris

{"title":"Petrochemistry and age of garnet-bearing xenoliths and their host volcanic rocks of Central Anatolia, Turkey: Implications for the evolution of magma-hydrothermal systems","authors":"Aslıhan Korkmaz Eryılmaz , Elif Varol , G. Deniz Doğan-Külahcı , Sibel Erkül , Chris Harris","doi":"10.1016/j.chemer.2024.126165","DOIUrl":null,"url":null,"abstract":"<div><div>The Hisarlıkaya volcanic rocks (HVR) are located southwest of Ankara, and presents a complex magmatic and metamorphic evolution. Understanding its petrogenesis provides crucial insights into the geological processes and magma evolution in Central Anatolia. This paper presents mineral chemistry, whole-rock major, trace element and Sr-Nd-O isotope, 40Ar-39Ar age of host volcanic rocks for magmatism and U-Pb dating of garnet for crystallization of contact metamorphosed rocks to constrain the magma source and the metasomatic processes in the contact zone of magma intrusion. The HVR samples have SiO2 from 60 to 64 wt%, Al2O3 (16–18 wt%), MgO (1.1–2.4 wt%), high concentrations of Large Ion Lithophile Elements (LILEs) and Light Rare Earth Elements (LREEs), and low concentrations of High Field Strength Elements (HFSEs) and Heavy Rare Earth Elements (HREEs), and high Sr/Y (70–90) and La/Yb (43–55) ratios. The HVR consists of trachytes and trachyandesites, displaying calc-alkaline characteristics with adakitic features with these geochemical properties. Initial 143Nd/144Nd, 87Sr/86Sr ratios, and δ18O values of HVR rocks are between 0.51263–0.51271, 0.70537–0.70542, and 8.60–9.20 ‰, respectively. These features together with geothermobarometric estimates suggest that the crystallization depth of the HVR's plagioclases and amphiboles was ∼25–30 km. Magmatism was initiated by partial melting of hydrated lithospheric mantle wedge in the Early Cretaceous followed by magmatic underplating and eruption of more felsic magma derived partly from the thickened lower crust.</div><div>These volcanic rocks contain xenoliths of quartzite, hornfels, and garnet-bearing skarn presumed to be from the contact zone. These were metamorphosed during earlier subduction and were subsequently assimilated and extruded by HVR magma. The 40Ar-39Ar plateau age of the HVR is 20.25 ± 0.10 Ma and the U-Pb dating of two garnet crystals from the skarn xenoliths are determined to be 22.08 ± 0.18 Ma to 21.30 ± 0.17 Ma, indicating that mineralization in the hydrothermal-metasomatic alteration zone is older and/or approximately contemporaneous with magmatism.</div></div>","PeriodicalId":55973,"journal":{"name":"Chemie Der Erde-Geochemistry","volume":"84 4","pages":"Article 126165"},"PeriodicalIF":2.6000,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemie Der Erde-Geochemistry","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0009281924000904","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}

引用次数: 0

Abstract

The Hisarlıkaya volcanic rocks (HVR) are located southwest of Ankara, and presents a complex magmatic and metamorphic evolution. Understanding its petrogenesis provides crucial insights into the geological processes and magma evolution in Central Anatolia. This paper presents mineral chemistry, whole-rock major, trace element and Sr-Nd-O isotope, ⁴⁰Ar-³⁹Ar age of host volcanic rocks for magmatism and U-Pb dating of garnet for crystallization of contact metamorphosed rocks to constrain the magma source and the metasomatic processes in the contact zone of magma intrusion. The HVR samples have SiO₂ from 60 to 64 wt%, Al₂O₃ (16–18 wt%), MgO (1.1–2.4 wt%), high concentrations of Large Ion Lithophile Elements (LILEs) and Light Rare Earth Elements (LREEs), and low concentrations of High Field Strength Elements (HFSEs) and Heavy Rare Earth Elements (HREEs), and high Sr/Y (70–90) and La/Yb (43–55) ratios. The HVR consists of trachytes and trachyandesites, displaying calc-alkaline characteristics with adakitic features with these geochemical properties. Initial ¹⁴³Nd/¹⁴⁴Nd, ⁸⁷Sr/⁸⁶Sr ratios, and δ¹⁸O values of HVR rocks are between 0.51263–0.51271, 0.70537–0.70542, and 8.60–9.20 ‰, respectively. These features together with geothermobarometric estimates suggest that the crystallization depth of the HVR's plagioclases and amphiboles was ∼25–30 km. Magmatism was initiated by partial melting of hydrated lithospheric mantle wedge in the Early Cretaceous followed by magmatic underplating and eruption of more felsic magma derived partly from the thickened lower crust.

These volcanic rocks contain xenoliths of quartzite, hornfels, and garnet-bearing skarn presumed to be from the contact zone. These were metamorphosed during earlier subduction and were subsequently assimilated and extruded by HVR magma. The ⁴⁰Ar-³⁹Ar plateau age of the HVR is 20.25 ± 0.10 Ma and the U-Pb dating of two garnet crystals from the skarn xenoliths are determined to be 22.08 ± 0.18 Ma to 21.30 ± 0.17 Ma, indicating that mineralization in the hydrothermal-metasomatic alteration zone is older and/or approximately contemporaneous with magmatism.

查看原文本刊更多论文

土耳其安纳托利亚中部含石榴石异岩石及其主火山岩的岩石化学和年龄：岩浆-热液系统演变的影响

Hisarlıkaya火山岩（HVR）位于安卡拉西南部，呈现出复杂的岩浆变质演化过程。了解它的岩石成因为了解安纳托利亚中部的地质过程和岩浆演化提供了至关重要的见解。通过矿物化学、全岩主要元素、微量元素和Sr-Nd-O同位素、岩浆作用的寄主火山岩的40Ar-39Ar年龄和接触变质岩结晶的石榴石U-Pb年龄来约束岩浆源和岩浆侵入接触带的交代过程。HVR样品的SiO2含量为60 ~ 64 wt%， Al2O3含量为16 ~ 18 wt%， MgO含量为1.1 ~ 2.4 wt%，大离子亲石元素（LILEs）和轻稀土元素（lree）含量较高，高场强元素（hfse）和重稀土元素（hree）含量较低，Sr/Y（70 ~ 90）和La/Yb（43 ~ 55）含量较高。HVR由粗面岩和粗面山岩组成，具有钙碱性特征和达质特征，具有这些地球化学特征。HVR岩石初始143Nd/144Nd比值为0.51263 ~ 0.51271‰，87Sr/86Sr比值为0.70537 ~ 0.70542‰，δ18O值为8.60 ~ 9.20‰。这些特征与地温压估算表明，HVR斜长石和角闪石的结晶深度为~ 25-30 km。岩浆活动是由早白垩世水合岩石圈地幔楔的部分熔融开始的，随后是岩浆底侵和部分来自下地壳增厚的长英质岩浆的喷发。这些火山岩含有石英岩、角砾岩和含石榴石的矽卡岩捕虏体，据推测来自接触带。它们在早期俯冲过程中变质，随后被HVR岩浆同化和挤压。热液交代蚀变带的40Ar-39Ar高原年龄为20.25±0.10 Ma，两颗卡岩包体石榴石U-Pb定年为22.08±0.18 ~ 21.30±0.17 Ma，表明热液交代蚀变带的成矿时间较早，与岩浆作用大致同生。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Chemie Der Erde-Geochemistry 地学-地球化学与地球物理

CiteScore

7.10

自引率

0.00%

发文量

审稿时长

3.0 months

期刊介绍： GEOCHEMISTRY was founded as Chemie der Erde 1914 in Jena, and, hence, is one of the oldest journals for geochemistry-related topics. GEOCHEMISTRY (formerly Chemie der Erde / Geochemistry) publishes original research papers, short communications, reviews of selected topics, and high-class invited review articles addressed at broad geosciences audience. Publications dealing with interdisciplinary questions are particularly welcome. Young scientists are especially encouraged to submit their work. Contributions will be published exclusively in English. The journal, through very personalized consultation and its worldwide distribution, offers entry into the world of international scientific communication, and promotes interdisciplinary discussion on chemical problems in a broad spectrum of geosciences. The following topics are covered by the expertise of the members of the editorial board (see below): -cosmochemistry, meteoritics- igneous, metamorphic, and sedimentary petrology- volcanology- low & high temperature geochemistry- experimental - theoretical - field related studies- mineralogy - crystallography- environmental geosciences- archaeometry