mineralogical and sedimentological studies ofinnershelf and beach sediments along thecoast

212 Pages·2014·9.98 MB·English

by  Terry Mechado

MINERALOGICAL AND SEDIMENTOLOGICAL STUDIES OF
INNERSHELF AND BEACH SEDIMENTS ALONG THE
COAST BETWEEN PARAVUR AND KOVALAM,
SOUTH KERALA, INDIA
Thesis submitted to the
COCHIN UNIVERSITY OF SCIENCE AND TECHNOLOGY
for the degree of
DOCTOR OF PHILOSOPHY
in Marine Geology under the
FACULTY OF MARINE SCIENCES
TERRY MACHADO
CENTRE FOR EARTH SCIENCE STUDIES
THIRUVANANTHAPURAM-695 031
April 1995
To My Dad and Mom
Xavier and Princy
DECLARATION
I do hereby declare that this Thesis contains results of research
carried out by me under the guidance of Prof. P. Seralathan. Marine Geology
Division, School of Marine Sciences, Cochin University of Science & Technology
and has not previously formed the basis of the award of any degree, diploma,
associateship, fellowship or other similar title of recognition.
Terry Machado
Centre for.. Earth Science Studies
Thiruvananthapuram -695 031
Thiruvananthapuram
April 12, 1995.
CERTIFICATE
This is to certify that this Thesis is an authentic record of research
work carried out by Mr.Terry Machado under my supervision and guidance in
the Centre for Earth Science Studies for Ph. D. Degree of the Cochin University
of Science and Technology and no part of it has previously formed the basis
for the award of any other degree in any University.
:7 /L LlSiE:; '
Prof. P. Seralathan
(Research Guide)
Marine Geology Division
School of Marine Sciences
Cochin University of Science 8c Technology
Kochi - 682 016
Kochi
April 12, 1995.
CONTENTS
CONTENTS
LIST OF FIGURES
LIST OF PLATES
LIST OF TABLES
ACKNOWLEDGEMENT
PREFACE
CHAPTER I INTRODUCTION
I.1. OBJECTIVES
I.2. GEOLOGY OF THE HINTERLAND
I.3. DRAINAGE 12
|.4. CLIMATE 14
I.5. FIELD OBSERVATION 8- SAMPLE COLLECTION 16
CHAPTER II GEOMORPHOMETRY 18
I|.1 INTRODUCTION 18
|l.2 METHODS 22
|I.2.1 Morphometrics of beaches 22­
||.2.2. Beach Sediment Transport study
Using Fluorescent Tracers 23
II.2.3. Wave Refraction Studies 26
II.3. RESULTS 26
Beach profiles 26
||.4 DISCUSSION 29
Erosional Phase of SW monsoon 29
Accretionary phase 31
Tracer Experiments 33
Wave Refraction Studies 36
Bathymetry and innershelf morphology 37
CHAPTER III GRANULOM ETRY 40
III.1 INTRODUCTION 40
II|.2 METHODS 43
I|I.3 RESULTS 44
||I.3.A. INNERSHELF 44
||I.3.A.1. Sediment distribution 44
l|l.3.a.2. Size Parameters
46
IIl.3.B. BEACH 50
lII.3.B.1. Size Parameters
50
l|I.4 DISCUSSION 54
l|I.4.A SEDIMENTATION PROCESSES 61
CM Diagram 62
Sediment transport in the Innershelf 63
Micro morphology of sediment grains 67
CHAPTER IV MINERALOGY 69
lV.1 INTRODUCTION 69
|V.2 METHODS 71
|V.2.A Heavy mineral quantification 71
IV.2.B Varietal studies
72
|V.2.C Electron Microprobe Analysis 76
|V.3 RESULTS 77
lV.3.A Heavy mineral content in the innershelf
sediments 77
IV.3.B Varietal studies
81
|V.3.C Electron Microprobe Analysis of Garnet
IV.4 DISCUSSION
IV.4.A Innershelf
|V.4.B Beach
OGGGm_L_L_b
CHAPTER V GEOCHEMISTRY a9
V.1 INTRODUCTION 89"
V.2 METHODS 91
V.3 RESULTS 92
V.4 DISCUSSION 96
CHAPTER VI SUMMARY AND CONCLUSIONS 106
REFERENCES 110
List of figures
Fig. 1.1. Location of the study area
Fig. 1.2. Geology of the hinterland
Fig. 1.3. Drainage map of the hinterland
Fig. 1.4. Wind Rose for Trivandrum for different seasons
Fig. 1.5. Location of sampling stations 8. echo-profiles shown in Plate 1.
Fig. 2.1. Location of beach profiling stations 8. tracer study sites
Fig. 2.2. Annual variation in breaker angel and littoral drift
Fig. 2.3. Refraction patternicvaves during fair weather season
Fig. 2.4. Refraction pattern:tvaves during SW monsoon season
Fig. 2.5. Beach profile at Panathura ( Prof. # 22)
Fig. 2.6. Beach profile at Perumathura (Prof. # 50)
Fig. 2.7a. Tracer distribution map at Panathura
Fig. 2.7b. Tracer distribution map at Panathura
Fig. 2.8a. Tracer distribution map at Kovalam
Fig. 2.8b. Tracer distribution map at Kovalam
Fig. 2.9a. Tracer distribution map at Ava
Fig. 2.9b. Tracer distribution map at Ava
Fig. 3.1 Distribution of sand in the innershelf region
Fig. 3.2 Distribution of silt in the innershelf region
Fig. 3.3 Distribution of clay in the innershelf region
3.4 Distribution of mean size in the innershelf sediment
Fig.
3.5 Distribution of skewness in the innershelf sediment
Fig.
3.6 Distribution of kurtosis in the innershelf sediment
Fig.
3.6A Distribution of sandzmud ratio in the innershelf sediment
Fig.
Fig. 3.7 Frequency distribution of mean size it; innershelf sediment
Fig. 3.8 Frequency distribution of standard deviation its innershelf sediment
Fig. 3.9 Frequency distribution of skewness in innershelf sediment
Fig. 3.10 Frequency distribution of kurtosis in innershelf sediment
Fig. 3.11 Mean size Vs. standard deviation cross plot for innershelf
sediment
Fig. 3.12 Mean size Vs. skewness cross plot for innershelf sediment
Fig. 3.13 Mean size Vs. kurtosis cross plot for innershelf sediment
Fig. 3.14 Standard deviation Vs. skewness cross plot for innershelf
sediment
Fig. 3.15 Standard deviation Vs. kurtosis cross plot for innershelf sediment
Fig. 3.16 Skewness Vs. kurtosis cross plot for innershelf sediment
Fig. 3.17 Bar chart showing variation of grain size of beach sediments
(Monsoon)
Fig. 3.18 Bar chart showing variation of grain size of beach sediments
(Post monsoon)
Fig. 3.19 Mean size Vs. standard deviation cross plot for beach sediment
Fig. 3.20 Mean size Vs. skewness cross plot for beach sediment
Fig. 3.21 Mean size Vs. kurtosis cross plot for beach sediment
Fig. 3.22 Standard deviation Vs. skewness cross plot for beach sediment
Fig. 3.23 Standard deviation Vs. kurtosis cross plot for beach sediment
Fig. 3.24 Skewness Vs. kurtosis cross plot for beach sediment
Fig. 3.25 CM diagram for innershelf sediment
Fig. 3.26 Sediment transport direction derived from McLaren's model
Fig. 4.1 Varietal index cross plot for SPi Vs. ZMi
Fig. 4.2 Varietai index cross plot for SPi Vs. GAi
Fig. 4.3 Distribution of total heavy mineral in inner shelf sediment
/
Fig. 4.4 Distribution of opaques in innershelf sediment
4.5 Distribution of ilmenite in innershelf sediment
Fig.
Fig. 4.6 Distribution of magnetite in innershelf sediment
4.7 Distribution of siilimanite in innershelf sediment
Fig.
4.8
Fig. Distribution of P)/1-ax£n25 in innershelf sediment
Fig. 4.9 Distribution of kyanite in innershelf sediment
4.10 Distribution of rutiie in innershelf sediment
Fig.
Fig. 4.11 Distribution of aragonite in innershelf sediment
Fig. 4.12 Distribution of garnet in innershelf sediment
4.13 Distribution of monazite in innershelf sediment
Fig.
4.14 Distribution of zircon in innershelf sediment
Fig.
Fig. 4.15 Ternary plots garnets from southern and northern sectors
Fig. 4.16 Pie diagrams showing the distribution of different rock types (13 the
hinterland
Fig. 4.17 Bar chart showing the concentration of heavy minerals in the
coarser (>125p) and finer (<125p )fraction of inner shelf
sediment.
Fig. 4.18 Variation of some selected heavy minerals in the beaches of study
area.
DISTRIBUTION PATTERN OF SOME MAJOR ELEMENTS:
Fig.5.1 SiO,
Fig.5.2 A|,O,
Fig.5.3 F e20,
Fig.5.4 CaO
Fig.5.5 MgO
Fig.5.6 TiO2
Fig.5.7 K20
FREQUENCY CLASS INTERVAL:
Fig.5.8 SiO2
Fig.5.9 Al,O,
Fig.5.1O Fe,O3
Fig.5.11 CaO
Fig.5.12 Na2O
Fig.5.13 K20
Fig.5.14 TiO,
DISTRIBUTION PATTERN OF SOME TRACE ELEMENTS:
Fig.5.15 Mn
Fig.5.16 Cu
Fig.5.17 Co
Fig.5.18 Cr
Fig.5.19 Ni
Fig.5.2O Cd
Fig.5.21 Pb
Fig.5.22 Zn
Fig.5.23 Ti
Fig.5.24 Th
Fig.5.25 u
FREQUENCY CLASS INTERVAL
Fig.5.26 Cd
Fig.5.27 Zn
Fig.5.28 Ni
Fig.5.29 Co
Fig.5.3O Mn
Fig.5.31 Pb
Fig.5.32 - Cu
Fig.5.33 Cr
Fig.5.34 Be
Fig.5.35 Th
Fig.5.36 U
Fig.5.37 V
Fig.5.38 Ti