The Zhob ophiolite comprises the Naweoba, Omzha and Ali Khanzai blocks, which are surrounded by the sediments of the Alozai Group and Loralai Formation. The Ali Khanzai Block contains metamorphic, ultramafic, gabbroic...The Zhob ophiolite comprises the Naweoba, Omzha and Ali Khanzai blocks, which are surrounded by the sediments of the Alozai Group and Loralai Formation. The Ali Khanzai Block contains metamorphic, ultramafic, gabbroic, volcanic and volcaniclastic rocks with associated chert. The Zhob manganese deposits found in the Ali Khanzai Block, occur in banded, lenticular and massive forms within red to brown coloured metachert. Braunite and pyrolusite are the main constituent manganese-bearing minerals with minor hausmannite, hematite and barite while quartz is the major gangue mineral with some carbonate minerals. Geochemical evidence from the major oxides indicates that the manganese mineralization and associated metachert at Zhob were formed by hydrothermal activity with little contribution from contemporaneous volcanic materials and this is confirmed by high Fe/Mn and low Co/Zn ratios and trace element patterns. These deposits formed along with seafloor spreading centres and were later obducted as part of Ali Khanzai Block of Zhob ophiolite.展开更多
Zhob valley ophiolite comprises Khanozai,Muslim Bagh,and Zhob chromitite occurrences located in Pakistan.These occurrences occur in massive,disseminated and nodular which exhibit both magmatic and deformational textur...Zhob valley ophiolite comprises Khanozai,Muslim Bagh,and Zhob chromitite occurrences located in Pakistan.These occurrences occur in massive,disseminated and nodular which exhibit both magmatic and deformational texture.The Muslim Bagh and Khanozai chromitites are classified into high-Cr chromitite(Cr#=0.66-0.85)while Zhob chromitite falls into high-Al chromitite(Cr#=0.53-0.58)composition.展开更多
基金the six months,HRD Foreign scholarships of the Centre of Excellence in Mineralogy,University of Balochistan,Quetta,which was approved by the Higher Education Commission,Pakistan under its PSDP development project“Capacity Building and Strengthening of the Centre of Excellence in Mineralogy”partly supported by the Higher Education Commission,Pakistan“National Research Program for Universities(NRPU)Project#3593”to Muhammad Ishaq Kakar。
文摘The Zhob ophiolite comprises the Naweoba, Omzha and Ali Khanzai blocks, which are surrounded by the sediments of the Alozai Group and Loralai Formation. The Ali Khanzai Block contains metamorphic, ultramafic, gabbroic, volcanic and volcaniclastic rocks with associated chert. The Zhob manganese deposits found in the Ali Khanzai Block, occur in banded, lenticular and massive forms within red to brown coloured metachert. Braunite and pyrolusite are the main constituent manganese-bearing minerals with minor hausmannite, hematite and barite while quartz is the major gangue mineral with some carbonate minerals. Geochemical evidence from the major oxides indicates that the manganese mineralization and associated metachert at Zhob were formed by hydrothermal activity with little contribution from contemporaneous volcanic materials and this is confirmed by high Fe/Mn and low Co/Zn ratios and trace element patterns. These deposits formed along with seafloor spreading centres and were later obducted as part of Ali Khanzai Block of Zhob ophiolite.
基金financially supported by the six months,HRD Foreign scholarships of the Centre of Excellence in Mineralogy,University of Baluchistan,Quetta,which was approved by the Higher Education Commission,Pakistan under its PSDP development project“Capacity Building and Strengthening of the Centre of Excellence in Mineralogy”.The research was also partly supported by Higher Education Commission,Pakistan“National Research Program for Universities(NRPU)Project#3593”to M.Ishaq Kakar.The authors are grateful to Editor-in-Chief and reviewers for their constructive comments which improved the manuscript.
文摘Zhob valley ophiolite comprises Khanozai,Muslim Bagh,and Zhob chromitite occurrences located in Pakistan.These occurrences occur in massive,disseminated and nodular which exhibit both magmatic and deformational texture.The Muslim Bagh and Khanozai chromitites are classified into high-Cr chromitite(Cr#=0.66-0.85)while Zhob chromitite falls into high-Al chromitite(Cr#=0.53-0.58)composition.
