Geochemistry, petrogenesis and tectonic significance of the basic volcanic units of the Zildat ophiolitic mélange, Indus suture zone, eastern Ladakh (India)

Ahmad, Talat; Islam, R.; Khanna, P. P.; Thakur, V. C.

doi:10.1080/09853111.1996.11105287

Cited by 43 publications

(17 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Parh group of volcanic rocks of northwestern Baluchistan are interpreted to be precursors of Deccan Traps and represent lavas from the Reunion hotspot (Wazir Khan et al, 1999). In the Tethyan ophiolites, island arc volcanics are associated with OIB type-hotspot lavas (Islam et al, 2003;Ahmad et al, 1996). This resemblance between the Archaean and younger island arc-plume basalts, adakites, boninites and other volcanic rocks from the Tethys and Pacific shows that the geodynamic processes operating in the Archaean and Mesozoic might not be much different except in the velocity and frequency of subduction and the size of the plates; the Archaean Era was dominated by faster Wilson cycles and frequent plume impingements and slab-wedge melting processes comparable with those of the Cenozoic Era.…”

Section: Discussionmentioning

confidence: 99%

Geochemistry of the NeoArchaean high-Mg basalts, boninites and adakites from the Kushtagi–Hungund greenstone belt of the Eastern Dharwar Craton (EDC); implications for the tectonic setting

Naqvi

Khan

Manikyamba

et al. 2006

Journal of Asian Earth Sciences

105

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Geochemistry of the NeoArchaean high-Mg basalts, boninites and adakites from the Kushtagi–Hungund greenstone belt of the Eastern Dharwar Craton (EDC); implications for the tectonic setting

Naqvi

Khan

Manikyamba

et al. 2006

Journal of Asian Earth Sciences

105

View full text Add to dashboard Cite

“…These ophiolitic rocks consist of chaotic blocks of schistose basic volcanics, agglomerates, amygdaloidal basalt, chlorite schist, deformed conglomerate schist, glaucophane schist, slates and large lenses of pe lagic limestones dispersed in a turbiditic matrix (Thakur and Misra, 1984;Sinha and Upadhyay, 1990). The basaltic rocks show predominantly OIB-E-MORB and minor N-MORB trace-element characteristics (Honegger et al, 1989, Ahmad et al, 1996 Harris et al ., 1988). Dashed rectangles show the outlines of study areas in eastern Ladakh ( Fig .…”

Section: Geological Settingmentioning

confidence: 99%

“…Concentrations of Ce, Sm and Gd were measured using the separated REE fraction of a rock standard of matching matrix. The accu racy and precision are described in Ahmad et al (1996). The chemical data are shown in Tables 1, 2 and 3. Elemental mobility A series of binary plots, showing inter-element relationships, use Si02, MgO, K20 and Zr for the enclaves and mafic dykes (Fig.…”

Section: Ladakh Granitoidmentioning

confidence: 99%

Geochemistry and geodynamic implications of magmatic rocks from the Trans-Himalayan arc.

et al. 1998

Self Cite

View full text Add to dashboard Cite

Present study aims at understanding the genetic and tectonic relationship between the enclaves and enclosing granitoids, acidic volcanics and mafic dykes of the Ladakh plutonic complex . Similar rocks from Lhasa Block (Tibet) are also studied and compared. In terms of Si02 abundance , the enclaves vary in composition from basic to acidic but are predominantly andesitic-basalt . Mafic dykes intruding the Ladakh plutonic complex are of predominantly andesitic-basalt composition. Granitoids and acidic volcanics from Ladakh and Lhasa blocks are compositionally granodiorite, quartz monzonite and granite . They are predominantly meta-aluminous with slight peraluminous characters. The acidic volcanics, however, have K20/Na2O > 1. All these rocks show calc-alkaline characteristics with high A1203 abundance , their rare earth elements (REE) and multi-element patterns depict enrichment of large ion lithophile elements (LILE)-light REE (LREE) and depletion of high field strength elements (HFSE) including Nb , P and Ti.

show abstract

“…The residue was dissolved in 1N HNO 3 and 100 ml solution was then ready for analysis. Precision for the major oxides was always better than 1.5%, for P 2 O 5 , MnO and trace elements it was better than 5%, and for REE better than 10% (Ahmad et al 1996).…”

Section: Analytical Techniquesmentioning

confidence: 83%

Petrography, geochemistry and regional significance of crystalline klippen in the Garhwal Lesser Himalaya, India

et al. 2011

View full text Add to dashboard Cite

Uphalda gneisses (UG) is a crystalline klippe located near Srinagar in Garhwal Himalaya. These gneisses are compared with Debguru porphyroids (DP) (≈Ramgarh group) of Garhwal-Kumaun Himalaya and Baragaon mylonitic gneisses (BMG) of Himachal Himalaya. Petrographic study reveals that the deformation of UG was initiated at higher temperature (above 350 • C) and continued till lowering of temperature and deformation led to the mylonitization.Geochemically, these granitic gneisses (UG, DP and BMG) exhibit similar composition. Features such as high molecular A/CNK value (>1), presence of normative corundum and absence of normative diopside, enhanced Rb/Sr, Rb/Zr ratios, enrichment of Th and containing rounded zircons support their crustally-derived S-type granitic nature. The linear plot in major oxides is interpreted in terms of fractional crystallization processes. Mantle normalized multi-element spider diagram of UG illustrates depletion of Ba, Nb, Sr, P and Ti and enrichment of Th and show similarities with DP and BMG.Similarities were observed in lithology, petrographic characters and chemical composition of UG, DP, BMG and Ulleri augen gneisses (Nepal). Comparison with the rocks of Higher Himalayan crystallines (≈Vaikrita), suggests that these rocks (UG) are not transported from Higher Himalaya as understood earlier. This study however proposes that, these gneissic bodies represent an older basement occurring as a tectonic sliver which emplaced within the cover sequence as wedges at different structural levels. This is a regional phenomena observed throughout the Lesser Himalayan region.

show abstract

Geochemistry, petrogenesis and tectonic significance of the basic volcanic units of the Zildat ophiolitic mélange, Indus suture zone, eastern Ladakh (India)

Cited by 43 publications

References 2 publications

Geochemistry of the NeoArchaean high-Mg basalts, boninites and adakites from the Kushtagi–Hungund greenstone belt of the Eastern Dharwar Craton (EDC); implications for the tectonic setting

Geochemistry of the NeoArchaean high-Mg basalts, boninites and adakites from the Kushtagi–Hungund greenstone belt of the Eastern Dharwar Craton (EDC); implications for the tectonic setting

Geochemistry and geodynamic implications of magmatic rocks from the Trans-Himalayan arc.

Petrography, geochemistry and regional significance of crystalline klippen in the Garhwal Lesser Himalaya, India

Contact Info

Product

Resources

About