I= PETROLOGY AND GEOCHEMISTRY OF THE PANJAL VOLCANICS IN THE AZAD KASHMIR AND KAGHAN AREAS OF THE NW HIMALAYA
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Title of Thesis
PETROLOGY AND GEOCHEMISTRY OF THE PANJAL VOLCANICS IN THE AZAD KASHMIR AND KAGHAN AREAS OF THE NW HIMALAYA

Author(s)
Mohammad Sabir Khan
Institute/University/Department Details
University of the Punjab
Session
1994
Subject
Geography
Number of Pages
270
Keywords (Extracted from title, table of contents and abstract of thesis)
panjal volcanics, geological setting, kahuta, jhelum valley, physiography, himalaya, kaghan, azad kashmir, neelum valley

Abstract
In the northwest Himalaya of Pakistan, the panjal volcanics of the Kahuta, Muzaffarabad and Kaghan areas form an elongate exposure of the Permian to Triassic basalts. The Panjal volcanics wrap around the apex of the Hazara-Kashmir syntaxis. The basaltic exposure runs northwest-southeast and dips to the northeast.

The panjal volcanics structurally lie between the Panjal Thrust and the Main Boundary Thrust at the upper and lower structural levels, respectively. The Agglomeratic slates and the Panjal volcanics were formed in two phases In the first phase Agglomeratic slates were deposited in Late Carboniferous and were followed by the second phase eruptions of basaltic lavas that. took place during Permian to Triassic. The feeders to basaltic lavas in the northwest Himalaya of Pakistan have been dated at 284± to 262± 1 Ma by previous workers.

The volcanics are characterized by massive lava flows and pillow lavas with intercalations of limestone and bedded chert. The volcanics are metamorphosed to lower greenschist facies during Himalayan orogeny. The Panjal volcanics are variably vesicular and altered to chlorite, epidote, Fe-oxides, sodic plagioclase, actinolite and calcite. Petrographic and chemical data of the less altered volcanics indicate that they were originally pyroxene and plagioclase phyric tholeiites.

The Panjal volcanics were analysed for major, minor and trace elements to investigate their nature, origin and tectonic setting. Whole rock analyses (120) of the Panjal volcanics from the Kahuta, Muzaffarabad and Kaghan areas were plotted ill various discrimination diagrams. The geochemical data indicate that the Panjal volcanics are dominantly tholeiitic to mildly alkalic hasalts.

REE (La, Sm and Yb), Ti%, Zr and Y data suggest that the source rocks (Garnet lherzolite and lherzolite) for the Panjal volcanics have undergone variable degrees (13 to 28%) of partial melting. Geochemical variations in the Panjal volcanics indicate that these rocks have been effected by fractional crystallization, mantle heterogeneity and with some degrees of crustal contamination. The Panjal volcanic rocks are characterized by their higher Zr/Y (3.8 to 4.12) and Ti/Y (331 to 352) ratios than the N-MORB. In contrast, the trace elements (Zr/Nb = 2.6 to 33, Zr/Y = 3.8 to 4.12 and Ti/Y = 331 to 352) and chondrite normalized light rare earth elements (La/Yh)= 3.29 to 11.16, (Ce/Yb )= 2.83 to 8.62 and (La/Sm )= 1.96 to 41 data indicate within-plate to P-type mid ocean ridge basalts. The geochemical data plotted in tectono-magmatic discriminant diagrams also suggest a within plate to P-type mid ocean ridge environment.

The geology, geochemistry and tectonics of the Panjal volcanics show that the lava flows were erupted during the Permian-Triassic rifting and initiation of incipient ocean along the northern margin of India.

Download Full Thesis
5731.55 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
166.79 KB
2 1 Introduction 1
177.75 KB
  1.1 Scopoe Of Suty 1
  1.2 Location And Accessibility 2
  1.3 Phsiography 2
  1.4 Geological Setting 4
  1.5 Purpose Of Invetigation 7
  1.6 Purpose Of Investigation 8
  1.7 Method Of Study 11
3 2 General Geology 12
541.04 KB
  2.1 Geological Description 12
  2.2 Stratigraphy Of The Kahuta Area 23
  2.3 Stratigraphy Of The Muzaffarabad And Kaghan Area 22
  2.4 Structure Of The Area 37
4 3 Geology Of The Panjal Vocanics 41
674.14 KB
  3.1 General Statement 41
  3.2 Agglomeratic Slates In The Kahuta Area 42
  3.3 Agglomeratic Slates In The Jhelum Valley 46
  3.4 Agglomeratic Slatels In The Neelum Valley 47
  3.5 Agglomeratic Slates In The Kaghan Valley 50
  3.6 Panjal Volcanics Int The Kahuta Area 50
  3.7 Panjal Volcanics In The Jhelum Valley 55
  3.8 Panjal Volcanics In The Neelum Valley 59
  3.9 Panjal Volcanics In The Kaghan Valley 63
  3.10 Limestone/ Dolomits In Jhelum And Neelum Valleys 64
  3.11 Limestone/ Dolomite In The Kaghan Area 66
  3.12 Basisc Intrusive Bodies 67
5 4 Petrography Of The Panjal Volcanic Rocks 70
670.67 KB
  4.1 General Statement 70
  4.2 Petrography 72
6 5 Gechemistry And Petrogrenesis Of The Panjal Volcanic Rocks 88
2213.44 KB
  5.1 Genral Statement 88
  5.2 Normative Mineralogy Of The Panjal Volcanies 88
  5.3 Geochemsitry 90
  5.4 Alternatio And Metamorphism Of The Panjal Volcanic 114
  5.5 Petrogenesis Of The Panjal Volcanics 129
7 6 Tectono-Magamtic Envrionment Of The Panjal Volcanics 170
731.74 KB
  6.1 General Statement 170
  6.2 Discussion 171
  6.3 Geochemical Comparios Of The Panjal Volcanics With MORB 45 o N, P-TYPE MORB, OIT And Continetal Flood Basalts 197
  6.4 Conclusions 210
8 7 References 213
519.62 KB