published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

The objective of this project is to apply the Optical Stimulated Luminescence (OSL) technique to date the palaeo sediment from Mu Us Desert, part of the Inner Mongolia in northern China and reconstruct the palaeo environment. Five OSL samples were collected from Dagouwan, Salawusu River Valley at Inner Mongolia by Dr S. H. Li and his team in 2009. Extraction of 150μm to 180μm silt-size feldspar from collected dune sand, lacustrine facies and fluvial facies samples and running of luminescence dating therefore to obtain the age from 50ka to 90ka. Climate proxies - magnetic susceptibility, grain size, fossil vertebrates and fossil pollens have been analyzed and it is concluded that significant climate change occurred within this period, which change from domination of warm, humid and rainy summer monsoons (before 70ka) to cold, wind, windy strengthened dry winter wind and back to warm and humid again after 55ka. / published_or_final_version / Applied Geosciences / Master / Master of Science

Materials deposited in low-temperature environments are characterized by their small particle size. The activity of microorganisms in aqueous sedimentary environments may have effective impacts on the geochemical parameters, which consequently change the original mineralogical records. The characterization of the fine environmental materials, especially those related to the microbial mediation is usually overlooked, but is essential for studies in the field of environmental microbiology or records of environmental change. The Kamchatka volcanic hot springs have been extensively studied for their microbiology because of their unique geological setting and applications to our understanding of life in the extreme environment. In those hot springs, minerals commonly appear with various morphologies. The hot springs have been existed for 40,000 years. Authigenic minerals, such as clay minerals, silica, sulfur, sulfide, and sulfate were characterized. Two types of silica and silicified biota were observed. Elemental sulfur crystals were observed although they are thermodynamically unstable. Pyrite and gypsum showed high diversities in morphologies and crystal sizes. Single forms of pyrite crystals included: cube, pyritohedron, octahedron, and sphericities. Prismatic, prismatic pseudo-hexagonal, fibrous, tubular, lenticular and twinned gypsum crystals were observed. The co-existence of diverse crystal habits of gypsum implies a long-term interaction between hot spring geochemistry and the metabolisms of the microbial community. The morphology of gypsum in hot springs was compared with that of gypsum with hydrothermal genesis in Lower Cambrian black shale. The crystallization of gypsum in the black shale of the Lower Cambrian, which shows similar but less varied morphology, was influenced by post-depositional hydrothermal fluids. I suggest that the high diversities of the morphology and crystal size of gypsum in those hot springs represent the continuous mediation of microorganism, which could be used as mineral ecophysiological records of life not only on Earth, but on Mars. Comparatively, the Pearl River Delta sedimentary environments are characterized by low-temperature and different mineralogical assemblages. Based on lithological records and dating data, C/N and organic carbon isotope are used to identify alterations between terrestrial and marine depositional environments in borehole transect that build up seven stages of sedimentary records. Secondly, element intensities taken by X-ray fluorescence core scanner and %Fe(III) variation implied different sedimentary environment records (terrestrial and marine) in HKUV15. Detrital minerals and authigenic minerals (gypsum, opal, and pyrite) were observed and characterized by scanning electron microscope. Diatom and coccolithophorid genera were identified. Most of mineralogical and biological records showed depositional environments consistent with geochemical records. In the Pearl River Delta sedimentary samples, the microbial mediated mineralization only contributed a small fraction to the mineral assemblages, while in the hot springs, the microbial mediation had more influences on the nucleation of authigenic minerals, which was reflected by the high diversity of crystal size and morphology of sulfates, sulfides, and siliceous minerals. / published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

published_or_final_version / Geography and Geology / Master / Master of Philosophy

by Tse Sui-fai, Peter. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 161-169). / ABSTRACT --- p.ii / ACKNOWLEDGEMENT --- p.iv / TABLE OF CONTENTS --- p.vi / LIST OF TABLES --- p.ix / LIST OF FIGURES --- p.x / LIST OF PLATES --- p.xi / Chapter CHAPTER I --- INTRODUCTION / Chapter 1.1 --- Scope of the problem --- p.1 / Chapter 1.2 --- Occurrence of urban sediments in an urban setting --- p.6 / Chapter 1.3 --- Nature of urban sediments --- p.9 / Chapter 1.4 --- Importance of studying urban sediment --- p.9 / Chapter 1.5 --- Objectives of this research --- p.10 / Chapter 1.6 --- Structure of this research --- p.10 / Chapter CHAPTER II --- LITERATURE REVIEW / Chapter 2.1 --- Hydrological problems related to urbanisation --- p.13 / Chapter 2.2 --- Importance of the urban sediment on the environment --- p.15 / Chapter 2.2.1 --- Road surface sediments --- p.20 / Chapter 2.2.2 --- Gully pot or catchment sediments --- p.22 / Chapter 2.2.3 --- Sewer sediments --- p.24 / Chapter 2.3 --- Studies on the characteristics of urban sediments --- p.25 / Chapter 2.3.1 --- Particle size and volatile content --- p.26 / Chapter 2.3.2 --- Surface features identification by using the SEM --- p.27 / Chapter 2.3.3 --- Studies in sub-tropical humid areas --- p.28 / Chapter 2.4 --- Problems raised from the previous studies and directions --- p.29 / Chapter CHAPTER III --- STUDY AREA - FO TAN CATCHMENT / Chapter 3.1 --- Introduction --- p.31 / Chapter 3.1.1 --- Hong Kong --- p.32 / Chapter 3.2 --- Fo Tan Catchment --- p.38 / Chapter 3.2.1 --- Geology --- p.44 / Chapter 3.2.2 --- Landuse --- p.48 / Chapter 3.2.3 --- Road surface and traffic characteristics --- p.49 / Chapter 3.2.4 --- Stormwater drainage network --- p.54 / Chapter 3.2.5 --- A unique hydrological year --- p.55 / Chapter 3.3 --- Conclusion --- p.59 / Chapter CHAPTER IV --- METHODOLOGY / Chapter 4.1 --- Rationale for the research method --- p.60 / Chapter 4.1.1 --- Introduction --- p.60 / Chapter 4.1.2 --- Operationalisation of the concept --- p.62 / Chapter 4.1.2.1 --- Street surface sediments --- p.62 / Chapter 4.1.2.2 --- Gully pot sediments --- p.63 / Chapter 4.1.2.3 --- Sewer sediments --- p.63 / Chapter 4.1.2.4 --- Channel deposits --- p.64 / Chapter 4.1.3 --- Study area---Fo Tan --- p.64 / Chapter 4.2 --- Empirical data and their collection --- p.64 / Chapter 4.2.1 --- Sampling sites --- p.64 / Chapter 4.2.2 --- Sample collection --- p.65 / Chapter 4.2.2.1 --- Street surface sediments --- p.66 / Chapter 4.2.2.2 --- Gully pot sediments --- p.66 / Chapter 4.2.2.3 --- Channel deposits --- p.67 / Chapter 4.2.3 --- Sample treatment --- p.67 / Chapter 4.3 --- Analyses of samples --- p.68 / Chapter 4.3.1 --- Particle size distribution --- p.68 / Chapter 4.3.1.1 --- Dry sieving analysis --- p.69 / Chapter 4.3.2 --- Volatile solids --- p.69 / Chapter 4.3.3 --- Surface characteristics of sediment grains --- p.70 / Chapter 4.3.3.1 --- The use of scanning electron microscope (SEM) --- p.70 / Chapter 4.3.3.2 --- Preparation of samples --- p.71 / Chapter 4.3.4 --- Data analysis and presentation --- p.73 / Chapter 4.4 --- Conclusion --- p.74 / Chapter CHAPTER V --- PHYSICAL CHARACTERISTICS OF URBAN SEDIMENTS / Chapter 5.1 --- Introduction --- p.75 / Chapter 5.2 --- Results --- p.76 / Chapter 5.2.1 --- Composition of the street surface sediments --- p.76 / Chapter 5.2.2 --- Street surface sediment loading --- p.79 / Chapter 5.2.3 --- Loading rate with slope factor --- p.86 / Chapter 5.2.4 --- Street sediment loads in different landuse areas --- p.86 / Chapter 5.2.5 --- Particle size distribution of the sediments --- p.88 / Chapter 5.2.5.1 --- Particle sizing for different sites in the same environment --- p.88 / Chapter 5.2.5.2 --- Particle size distribution for different sampling dates --- p.89 / Chapter 5.2.5.3 --- Particle size distribution in different environments --- p.89 / Chapter 5.2.5.5 --- Phi study --- p.91 / Chapter 5.2.6 --- Bivariate scattergram analysis --- p.96 / Chapter 5.3 --- Discussion --- p.100 / Chapter CHAPTER VI --- VOLATILE SOLIDS ANALYSIS / Chapter 6.1 --- Introduction --- p.105 / Chapter 6.2 --- Results --- p.108 / Chapter 6.2.1 --- The mean volatile solids in different environments --- p.108 / Chapter 6.2.2 --- The relationship between phi median and volatile solids content --- p.109 / Chapter 6.2.3 --- Particle size distribution on the volatile solids content --- p.110 / Chapter 6.3 --- Discussion --- p.111 / Chapter 6.3.1 --- Effects of road surface characteristics --- p.111 / Chapter 6.3.2 --- Effects of traffic flow --- p.112 / Chapter 6.3.3 --- Effects of landuse pattern --- p.114 / Chapter 6.4 --- Particle size and volatile solids: a synthesis --- p.114 / Chapter 6.5 --- Conclusion --- p.119 / Chapter CHAPTER VII --- SCANNING ELECTRON MICROSCOPIC STUDY / Chapter 7.1 --- Introduction --- p.120 / Chapter 7.2 --- Results --- p.125 / Chapter 7.2.1 --- Quantitative analysis of the surface features on grains from different depositional environments --- p.125 / Chapter 7.2.2 --- Description of the texture of the samples --- p.130 / Chapter 7.2.3 --- Texture interpretation --- p.142 / Chapter 7.3 --- Discussions --- p.143 / Chapter 7.3.1 --- Surface texture description and its relationship to landuse pattern --- p.143 / Chapter 7.3.2 --- Sediment transport in an urban setting: a synthesis --- p.146 / Chapter CHAPTER VIII --- CONCLUSION / Chapter 8.1 --- Findings of this research --- p.152 / Chapter 8.2 --- Future directions --- p.157 / Chapter 8.2.1 --- Equipment used in reducing urban sediments --- p.157 / Chapter 8.2.2 --- Sweeping practices of the street surface --- p.158 / Chapter 8.2.3 --- The use of SEM in urban sediments --- p.159 / Chapter 8.3 --- Conclusions --- p.160 / REFERENCES --- p.161 / APPENDICES --- p.170

Bibliography: leaves 280-288. / xix, 288, [36] leaves, [15] leaves of plates : ill. (some col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study examines the medium sized sedimentary manganese deposit of Dounan, Yunnan Province of China, to determine the sedimentary environments controlling the distribution of ores and rocks, and to establish the relationships between ore mineralization and changes in the sedimentary environment. The thesis also aims to work out the sequence of events after the primary ore is formed, to determine which processes lead to secondary enrichment of the ore. / Thesis (Ph.D.)--University of Adelaide, Dept. of Geology and Geophysics, 1994

published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

published_or_final_version / Applied Geosciences / Master / Master of Science

published_or_final_version / Earth Sciences / Master / Master of Philosophy