TY - JOUR
T1 - Mineralogical and geochemical characterization of listwaenite from the Semail Ophiolite, Oman
AU - Nasir, Sobhi
AU - Al Sayigh, Abdul Razak
AU - Al Harthy, Abdulrahman
AU - Al-Khirbash, Salah
AU - Al-Jaaidi, Omar
AU - Musllam, Abdullah
AU - Al-Mishwat, Ali
AU - Al-Bu'saidi, Salim
N1 - Funding Information:
The authors would like to express their thanks to the Sultan Qaboos University for financial support. Thanks to all staff member at the Museum of Natural History, London for their cooperation and provision of the chemical analyses. S. Nasir thanks the DAAD for a short scholarship, which enabled him to stay 3 months at the Institute of Mineralogy, Würzburg, Germany. Thanks to Ulrich Schüssler, Würzburg for his assistant and discussion. Martin Okrusch is thanked for thorough reviews and discussions that have greatly improved the manuscript. Kirsten Druppel is thanked for supplying an excel spreadsheet for mass balance calculation.
PY - 2007/10/25
Y1 - 2007/10/25
N2 - The late Cretaceous-lower Tertiary hydrothermal alteration of serpentinized peridotite in the Semail ophiolite has formed two distinct types of listwaenite. Type I is characterized by the presence of calcite (Type IA) or dolomite (Type IB)+fuchsite±spinel. Type II is dominated by silicate minerals (quartz, chlorite, fuchsite)±calcite+dolomite±magnetite±apatite±plagioclase. Most listwaenites occur as veins along thrust fault zones within the ophiolite mélange. High Cr and Ni contents, abundant occurrence of Cr-spinel within a matrix of red-brown ferruginous carbonates within a micro-vein network of goethite, and the relics of mesh texture indicate an ultramafic protolith. Type I and II listwaenites represent different stages of hydrothermal alteration. The mineralogical and chemical distinctions of both types are the response to the extent of the reactions between the protoliths and the solutions leading to different stages of metasomatic replacement. The hydrothermal fluids involved in the formation of Type I listwaenite were enriched in Ca, Mg, and CO2, whereas Type II listwaenite bodies were formed from a hydrothermal fluid enriched in SiO2. REE and trace elements in both listwaenite types were extracted in part from adjoining peridotite. No Au anomaly in the study areas has been detected.
AB - The late Cretaceous-lower Tertiary hydrothermal alteration of serpentinized peridotite in the Semail ophiolite has formed two distinct types of listwaenite. Type I is characterized by the presence of calcite (Type IA) or dolomite (Type IB)+fuchsite±spinel. Type II is dominated by silicate minerals (quartz, chlorite, fuchsite)±calcite+dolomite±magnetite±apatite±plagioclase. Most listwaenites occur as veins along thrust fault zones within the ophiolite mélange. High Cr and Ni contents, abundant occurrence of Cr-spinel within a matrix of red-brown ferruginous carbonates within a micro-vein network of goethite, and the relics of mesh texture indicate an ultramafic protolith. Type I and II listwaenites represent different stages of hydrothermal alteration. The mineralogical and chemical distinctions of both types are the response to the extent of the reactions between the protoliths and the solutions leading to different stages of metasomatic replacement. The hydrothermal fluids involved in the formation of Type I listwaenite were enriched in Ca, Mg, and CO2, whereas Type II listwaenite bodies were formed from a hydrothermal fluid enriched in SiO2. REE and trace elements in both listwaenite types were extracted in part from adjoining peridotite. No Au anomaly in the study areas has been detected.
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U2 - 10.1016/j.chemer.2005.01.003
DO - 10.1016/j.chemer.2005.01.003
M3 - Article
AN - SCOPUS:34848922137
VL - 67
SP - 213
EP - 228
JO - Geochemistry
JF - Geochemistry
SN - 0009-2819
IS - 3
ER -