published_or_final_version / Applied Geosciences / Master / Master of Science

published_or_final_version / Applied Geosciences / Master / Master of Science

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

published_or_final_version / Applied Geosciences / Master / Master of Science

published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

published_or_final_version / Applied Geosciences / Master / Master of Science

published_or_final_version / Applied Geosciences / Master / Master of Science

published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

The Trans-North China Orogen (TNCO) has been recognized as a continent-continent collisional belt along which the Eastern and Western Blocks amalgamated to form the North China Craton. However, controversy has surrounded the timing and tectonic processes involved in the collision between the two blocks, ranging from the westward-directed subduction with final collision at ~2.5 Ga, through the west-dipping subduction with two collisional events at ~2.1 Ga and ~1.85 Ga, to the eastward-directed subduction with final collision at ~1.85 Ga. This project aims to present detailed lithostratigraphic, geochronological and isotopic data for the low-grade supracrustal successions in the TNCO to examine current models and to establish a reasonable scenario for the tectonic evolution of the TNCO in the Paleoproterozoic. The low-grade supracrustal successions include the Hutuo and Yejishan Groups in the middle sector of the TNCO and the Songjiashan, Lower Zhongtiao, Upper Zhongtiao, Danshanshi and Songshan Groups in the southern sector. Lithostratigraphic data indicate that the Songjiashan, Lower Zhongtiao Groups and lower parts of the Hutuo and Yejishan Groups are composed of metaclastic rocks, carbonates and metavolcanic rocks, interpreted as back-arc basin deposits, whereas the Upper Zhongtiao, Danshanshi, Songshan Groups and the upper parts of the Hutuo and Yejishan Groups consist only of metaconglomerates and metasandstones, interpreted as foreland basin deposits. To constrain the provenance and maximum depositional ages for these low-grade supracrustal successions, the LA-MC-ICP-MS technique was applied to analyze U-Pb and Hf isotopic compositions for detrital zircons from them. For the Hutuo and Yejishan Groups, we found major age peaks at ~2.5 and ~2.2 Ga and minor amounts of 2.8-2.6 Ga detrital zircons, which are consistent with ages of the lithological units in the middle sector of the TNCO. On the other hand, for the Songjiashan, Lower Zhongtiao, Upper Zhongtiao, Danshanshi and Songshan Groups, detrital zircons from them have the major age population of 2.85-1.95 Ma and the minor age population of 3.6-3.1 Ga, of which the former is comparable with ages of the lithological units in the southern sector of the TNCO and the latter was derived from the Paleoarchean and Mesoarchean crust of the Eastern Block. The maximum depositional ages of the low-grade supracrustal successions have also been well constrained in this study. For the back-arc basin deposits, their maximum depositional ages were constrained between ~2.15 and ~2.10 Ga. For the foreland basin deposits, the presence of ~1.85 Ga detrital zircons indicates that they were deposited after this time. Taken together, we present a brief scenario for the evolution of the sedimentary basins in the TNCO. At 2.15-2.10 Ga, a series of back-arc basins developed behind an “Andean-type” arc that were subsequently incorporated into the TNCO during the collision of the Eastern and Western Blocks. At ~1.85 Ga, the two blocks collided along the TNCO, resulting in the crustal thickening followed by rapid exhumation/uplift, which shifted the back-arc basins to foreland basins. Such a shift in the late Paleoproterozoic supports the model that the collision between the Eastern and Western Blocks occurred at ~1.85 Ga. / published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

A gap exists between people and geological treasures which they have failed to recognised, in particular their scientific, educational, cultural, and aesthetic values. In general, comprehensive treatment on conservation of geoheritage is missing in the local context. Identification of geoheritages may be the first step to bridge the gap, but there is no workable definition to start with. Some overseas authorities may give guidance to identify the targets, so an inventory of significant geoheritages can be established to facilitate their protection and monitoring. The need for conservation of geoheritages is generally overlooked. There are specific authorities and legislation to protect cultural heritages and biodiversity, but not so for geoheritages, even for those within the Geopark, which may fall victim to rapid economic development, a more potential impact than the natural processes of weathering and erosion. A similar conservation vacuum is also observed with many stone monuments which share the same fate as geoheritages. On the other hand, a close relationship exists among the biological, cultural/historical and geological aspects of a site to justify inclusion of geoheritages in the current conservation regime. An integral management approach could be an effective strategy for conserving these aspects within the same location. Appreciating geoheritages in the field brings nice surprises to the curious, which underpins that geology can be made an interesting and lively study. The theoretical discussions have been applied to a case study on Po Toi. A fieldtrip worksheet was designed to serve as an example for students and other interested members of the public who are encouraged to retrace the steps of the author in an enjoyable learning experience. / published_or_final_version / Applied Geosciences / Master / Master of Science