I= PETROTECTONICS, PETROLOGY AND GENESIS OF URANIUM MINERALISATION OF THE SIWALIK GROUP OF THATTI NASRATI AND SHAVAH-SHANAWAH AREA
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Title of Thesis
PETROTECTONICS, PETROLOGY AND GENESIS OF URANIUM MINERALISATION OF THE SIWALIK GROUP OF THATTI NASRATI AND SHAVAH-SHANAWAH AREA

Author(s)
Azizullah
Institute/University/Department Details
University Of Punjab Lahore
Session
1997
Subject
Geology
Number of Pages
275
Keywords (Extracted from title, table of contents and abstract of thesis)
petrotectonics, petrology, uranium mineralisation, siwalik group, thatti nasrati, shavah-shanawah, pliocene, pleistocene, chinji, nagri, dhok pathan, soan

Abstract
The Himalayan Malayan molasses sediments of the Siwalik Group, which range in age from Pliocene to Pleistocene is the Thatti-Nasrati and Shanawah-Godi Khel of Trans Indus areas were studied in order to understand their nature, origin chemical and petrotectonic investigations helped to understand the genesis of uranium mineralization in the Dhok Patthan Formation of the study area.

The Siwalik Group is comprised of four formations i.e. Chinji, Nagri, Dhok Pathan and Soan. The Rawalpindi Group is absent in this area. The Chinji age. This formation consists of maroon and reddish brown colored shale and subordinate sandstone horizons. The thickness of the Chinji Formation varies from 1160 m to 1400 m. The nagri formation is marked by a thick sequence of massive sandstone with a lot of palaeochannels. Shales are present as rare thin patches. The thickness of the Nagri Formation varies from 1050m to 2075m. The Dhok Pathan Formation exhibits excellent development of cyclic deposition of shale and sandstone. the thickness of this formation varies from 950m to 1200m. The soan formation consists of conglomerates sandstone, siltstone and shale horizons. The thickness of this formation varies from 300 to more than 500m.

A number of uranium bearing mineralized horizons are present in the upper part of the Dhok Pathan Formation. These horizons have secondary uranium mineral carnotite in the study area. Uranium mineralization is widely distributed throughout the Siwaliks. A few uranium deposits of small size source nor indeed the control of mineralization were properly understood. The size, of the discovered deposits are very small as compared to the regional surface showings.

The study of lateral and vertical accretion deposits, presence of scouring, channel abandonment behaviour, facies association and channel fill of the Siwalik Group sow that it was deposited by a braided river system. The Siwalik Group of the Shinghar-Surghar ranges were deposited from 12.M.a to 0.5M.a as compared to the siwaliks of the potwar plateau, where these sedimentation rates of the siwalik group were generally higher in the trans-indus ranges than that of the potwar plateau area. The entire molasse sequence covering the time span of 12M.a to 0.5 M.a is conformable. There was no tectonic activity other than subsidence of the basin till folding began about 0.5 Ma, which stopped the siwalik sedimentation in the study area. These molassic sediments were deposited by high velocity streams are indicated by the presence of pebbles, cobbles and boulders. Poor sorting and angularity of fragments as well as their compositional immaturity suggests that the sediments are texturally as well as compositionally immature. Within uranium bearing horizons the sandstone is subarkose to lithic arenite. The mineralized palaeochannels contain bentonitized volcanic clasts, which still retain 11 ppm uranium such volcanic clasts provided the indigenous and subtropical climatic conditions as it contains plant fragments and vanadium rich minerals. In some areas the formation contains considerable amount of humic acid and pyrite, formed during diagenesis. These served as important reductants for uranium deposition.

Studies based on nature, origin and conditions of deposition coupled with petrographic, chemical and petrotectonic investigations strongly suggest a potential for sandstone type uranium deposit in the Dhok pattan formation of the thatti nasrati and shanawah godi kehl area.

This potential deposit may be similar in characters to those of baghalchur. Nanagar nai and qabul khel areas. As a large number of surface samples of the study area have more than 0.05% chemical U3O8, further integration of data and exploration work particularly core drilling may prove the existence of a uranium deposit.

Download Full Thesis
5268.75 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Content
104.57 KB
2 1 Introduction
128.13 KB
  1.1 The Himalayan Molasses Sediments 1
  1.2 Previous Work 4
  1.3 Geology Of Thatti Nasarrti Shava Shanawah Area 7
  1.4 Uranium Mineralization 11
  1.5 Problems Of The Study Area 11
  1.6 Working Plan 12
3 2 Stratigraphy Of The Study Area And Its Surrounding 18
358.94 KB
  2.1 Zaluch Group 19
  2.2 Mianwali Formation 19
  2.3 Tredian Formation 20
  2.4 Kingriali Formation 21
  2.5 Datta Formation 22
  2.6 Samana Suk Limestone 22
  2.7 Chichali Formation 23
  2.8 Lumshiwal Formation 24
  2.9 Hangu Formation 25
  2.10 Lockhart Limestone 27
  2.11 Patala Formation 27
  2.12 Nammal Formation 28
  2.13 Sakesar Limestone 29
  2.14 Mitha Khatak Formation 30
  2.15 Wiwalik Group 32
4 3 The Siwalik Group 41
131.48 KB
  3.1 Chinji Formation 45
  3.2 Nagri Formation 47
  3.3 Dhok Pathan Formation 50
  3.4 Soan Formation 52
5 4 Sedimentology Of The Siwalik Group Of The Study Area 55
2490.61 KB
  4.1 Gravelly Facies 59
  4.2 Sandy Facies 61
  4.3 Fine Grained Facies 64
  4.4 Description Of The Chinji Formation 69
  4.5 Interpretation Of The Chinji Formation 76
  4.6 Description Of The Nagri Formation 82
  4.7 Interpretation Of The Nagri Formation 91
  4.8 Description Of The Dhok Pathan Formation 96
  4.9 Interpretation Of The Dhok Pathan Formation 103
  4.10 Description Of The Soan Formation 111
  4.11 Interpretation Of The Soan Formation 114
6 5 Structure Of The Study Area 117
234.42 KB
7 6 Description Of Mineralized Horizons Of The Study Area 128
673.68 KB
  6.1 Hard Sandstone Bands 128
  6.2 Carnotite Bearing Sandstone 131
  6.3 Details Of Anomalies 134
8 7 Geochemistry Of Uranium Properties 183
741.52 KB
  7.1 Uranium Properties 183
  7.2 Uranium In Igneous Rocks 186
  7.3 Uranium In Sedimentary Rocks 188
  7.4 Uranium In Metamorphic Rocks 197
  7.5 Uranium In Sedimentary Environments 199
  7.6 Precipitation Conditions Of Uranium During Diagenesis 204
  7.7 Precipitation Of Uranyl Minerals 208
  7.8 Sediment Hosted Mineralization 211
  7.9 Hydrochemical/Geochemical Studies Of The U-Bearing Horizons Of Pakistan 211
  7.10 Regional Hydrochemical Conditions Of U-Bearing Molasses Sediments 215
  7.11 Hydrochemical Characteristics And Uranium-Vanadium Distribution Patterns 223
  7.12 Geochemical Behaviour Of U Within The Siwalik Molasses 225
9 8 Sandstone Type Uranium Deposits / Occurrences Of Pakistan In Perspective Of World Sandstone Type Uranium Deposits 226
367.3 KB
  8.1 Introduction 226
  8.2 Tectonic Setting And Sedimentary Environments 228
  8.3 Distribution 230
  8.4 Host Rock Sedimentary Environments 243
  8.5 Uranium Mineralization 245
  8.6 Model 245
  8.7 Sandstone Type Uranium Deposits/Occurrences Of Pakistan 248
  8.8 Grain Size Distribution 253
  8.9 Pattern Of Stratification 255
  8.10 Palaeocurrent Studies 256