Sea Level Variations during the Late Quaternary and Coastal Evolution along the Northern Kerala ...

203 Pages·2011·8.88 MB·English

by  Haneesh Kumar

SEALEVELVARIATIONSDURING THELATEQUATERNARY
ANDCOASTALEVOLUTIONALONG THENORTHERN
KERALA~ SOUTH WESTOFINDIA
COCHINUNIVERSITYOFSCIENCEANDTECHNOLOGY
fO'l t'~ jladl.atft.ltfl.t.~Qtoft'~ !b~~'l~~ of
DOCTOROFPHILOSOPHY
la
M.riD.Gcolou
tJNDERTHEFACULTYOFMARINESCIENCES
CENTRE'OREARTHSCIENCESTUDIES
THlRUVANANTHAPURAM-69S031
dtta-, ~@@~
CERTIFICATE
This is to certify that this thesis entitled "SEA LEVEL VARIATIONS DURING THE
LATE QUA-rERNARY AND COASTAL EVOLUTION ALONG THE NORTHERN
KERALA, ~OUTH WEST OF INDIA", is an authentic record of the research work
carried out by Mr.Haneeshkumar.V under my supervision and guidance at the Marine
Science Division, Centre for Earth Science Studies, Thiruvananthapuram- 695 031 in
partial fulfil.ment of the requirements for the Ph.D. Degree of Cochin University of
Science and Technology, under the Faculty of Marine Sciences and no part thereof has
beenpresented for the award ofany degree in any University.
.'
Thiruvananthapuram D .M. Samsuddin
6May 2001 Research Supervisor &
Scientist Ell,.Marine Science Division
Centre for Earth Science Studies
Akkulam, Thiruvananthapuram 695 031
SEA LEVEL VARIATIONS DURING THE LATE QUATERNARY AND
COASTAL EVOLUTION ALONG THE NORTHERN KERALA,
SOUTHWEST OF INDIA
CONTENTS
PREFACE i
ACKNOWLEDGEMENTS v
LISTOF TABLES vii
LISTOF FIGURES viii
LISTOFPLATES xi
CHAPTER 1 INTRODUCTION
1.1 BACKGROUND 1
1.2 INTERNATIONALSTATUS 1
1.3 NATIONALSTATUS 4
1.3.1 East Coast 4
1.3.2 West Coast 6
1.3.2.1 Kerala scenario 7
1.4 OBJECTIVESOF THESTUDY 9
1.5 PHYSIOGRAPHY 10
1.6 GEOLOGYOF KERALA 10
1.7 CONTINENTALSHELFAND BATHYMETRY 12
1.8 CLIJ\1ATE 13
'''A
1.9 13
VE CLII\1ATE
1.10 FLUVIAL INPUTS 14
1.11 STUDYAREA 14
CHAPTER 2 COASTAL GEOMORPHOLOGY
2.1 BACKGROUND 16
2.2 NATUREOF THE KERALACOAST 16
2.3 J\1ETHODOLOGY 17
2.4 TRANSECT ELEVATION SECTIO~S 17
2.4.1 Punjavi Transect 21
2.4.2 Onakkunnu Transect 21
2.5 J\10RPHOLOGICAL FEATURES 22
2.5.1 Coastal Landfonns 23
2.5.1.1 Fluvial and estuarine landfonns 23
2.5.1.2 Marine landfonns 23
2.6 ORIGIN OF BEACH RIDGES 24
2.7 MORPHOLOGICAL EVIDENCESON SEA LEVEL
CHANGES 26
CHAPTER 3 COASTAL PLAIN SEQUENCES
3.1 BACKGROUND 33
3.2 METHODOLOGY 34
3.3 SEDIMENTARYFACIES 37
3.3.1 Sedimentary Facies-Punjavi Transect 44
3.3.2 Sedimentary Facies-Onakkunnu Transect 64
3.4 MINEROLOGICALCOMPOSITION 86
3.4.1 Heavy Mineral Composition 88
3.4.2 Heavy Mineral Provenance 88
3.4.3 Red Sands and Environmental Significance 90
CHAPTER 4 CONTINENTAL SHELF SEQUENCES
4.1 BACKGROUND 96
4.2 METHODOLOGY 98
4.3 SEDIMENTARY FACIES 98
4.3.1 Sedimentary Facies-Punjavi Transect 102
4.3.2 Sedimentary Facies-Onakkunnu Transect 115
4.4 CALCIUM CARBONATEAND ORGANIC MATTER
DISTRIBUTION 123
4.5 SIGNIFICANCEOF ORGANIC MATTERAND
CALCIUM CARBONATE 127
4.6 TEXTURALCONTROLOVERORGANIC MATTER
VARIATION 128
4.7 PRODUCTIVITYAND ORGANIC l\lATTERCONTENT 129
4.7 SEDIMENTATION RATEANDORGANIC MATTER
CONTENT 129
4.8 CALCIUM CARBONATE\'ERSUSORGANIC
MATTERDISTRIBUTION 130
4.10 NATUREOF SEDIl\:IENTACCUl\1ULATION PATTERN 130
CHAPTERS CORRELATION AND CHRONOLOGY
5.1 BACKGROUND 135
5.2 SEDIMENTOLOGICALAND MINERALOGICAL
EVIDENCES 137
5.3 RELICTSEDIMENTARY ENVIRONl\1ENT 142
5.4 CHRONOLOGICAL EVIDENCES 146
5.5 LATEQUATERNARYCOASTAL EVOLUTION
AND SEA LEVELCHANGES 150
5.5.1 Sea Level Variations: 36 kyr to 7 kyr 153
5.5.2 Regressive Episodes since 6000 YBP 155
5.5.3 Shoreline Positions ofNorthern Kerala
over Time (36 kyr to Present) 158
CHAPTER 6 SUMMARY AND CONCLUSIONS 161
REFERENCES
PREFACE
Coastal evolution during Quaternary is mainly related to sea level changes, and have
direct bearing on climatic oscillations. From IGCP 61 to IGCP 274, the concept ofa
singleuniform world-wide sea level curve transformed into site-specific regional sea level
curve. Significant contributions have been made world over to determine various
episodes ofmarine transgression and regression and efforts are going on for achieving
precision in establishing the sea level curvefrom a regionalperspective. During the last
two decades, studies to understand the nature of Holocene sea level fluctuation and
chronometric transgressional and regressional history ofwestern and eastern coasts of
Indiawere undertaken by many authors.
TheKerala coast is one ofthe least explored asfar as reconstruction ofsea level history
and coastal evolution are concerned. Most of the investigation on late Quaternary
sediments were based 011 studies on independent sequences either exposed inland or on
the shelfareas. However, no effort has been 111ade to derive a comprehensive picture of
coastal evolution and climatic changes along this part ofthe coast by integrating the
coastal andshelfsequences. In the present investigation, an attempt is made to document
various episodes oftransgression and regression during the late Quaternaryperiodfro111
thestudyofcoastal andshelfsequences extendingfrom the inlandacross the beach to the
shelf domain. Shore parallel beach ridges with alternating swales and occurrence of
strand line deposits on the shelf make the northern Kerala coast an ideal natural
laboratory for documenting the morpho-dynamic response ofthe coast to the changing
sea level. The present study is confined to two shore-normal east-west trending transects,
viz. Punjavi and Onakkunnu in the northern Kerala coast. These coastal plain transects
wereextendedfurther to the offshore up to the shelfedge.
The thesis is addressed in six chapters with further subdivision and sectionalization. In
thefirst chapter, significance ofthe work is introduced. Briefreview ofliterature includes
sections on national and international endeavors on Quaternary research. climate,
drainage, geology, physiography, nature ofthe continental shelfand bathymetry ofthe
studyarea are alsopresented. The studyarea is introducedin this chapter.
Morphologic setup ofthe study area derivedfrom the Survey ofIndia toposheets, satellite
images and air photos is dealt in the second chapter. Along the transects referred to
hitherto, plane table mapping was carried out in 1:2250 and J:5000 scale and reduced
levelswith respect to the Present Mean Sea Level (PMSL) ofdifferent sets ofbeach ridges
and swales were established. An attempt is made to infer the transgressional and
regressional history ofthe areafrom the perspective oforigin ofbeach ridges.
To understand variations in sedimentaryfacies, twenty three core samples varying in
depth between 7 and 11 metre were collectedfrom the coastal plain. The third chapter
dealswith the characteristic lithologicfeatures ofthe coastalplain sequences. down-core
variation ofthe grain size and heavy mineralsuite. Granulometric signatures are used to
reconstruct the past depositional environment. Morpho-stratigraphic disposition ofthe
coastal plain deposits are also inferred. Down-core variations in heavy' mineral
association is discussed in this chapter. III the light of their stability, dispersal and
provenance, an attempt is also made to elucidate the post-depositional transformation of
thesedeposits.
Shelf sequences are discussed in the fourth chapter. Textural attributes were used to
categorize the sediments into various types. An attempt is made here to gain insight into
the nature of modern/relict sedimentation. Climatic control over the sediment
accumulation pattern is inferred based distribution of organic matter. calcium
011
carbonate and radio-carbon dates. Rat~ ofsedimentation and the preservation potential
oforganic matteron the shelfsediment is also discussed.
Thefifth chapterdeals with correlation and chronologicalframework ofcoastal andshelf
sequences. Here, an attempt is made to derive evolutionaryphases ofthe northern ~erala
coast, by collating results from coastal geomorphology, correlation of sedimentary
11
sequencesand radio-carbon dates ofthe strandplain and adjoining shelfsequences. The
sixth chapter summarizes the salient points and the conclusions arrived at from the
presentinvestigation.
In connection with this thesis, following research papers/abstracts have beenpublishedin
differentnational/internationaljournals.
Haneeshkumar, JI:, Ramachandran, K.K., Samsuddin, M and Suchindan, G.K. 1999.
"Heavy mineral distribution in the Holocene Coastal sediments along the Northern
Kerala, India". Paper presented in the Meeting-cum-Workshop on Quaternary
coastal environments: Records of Rapid changes and responses held at
Bharathidasan University, Tiruchirapalli, October 1999. (Abstract vol. pp 13-15)
Haneeshkumar, JI:, Ramachandran, K.K., Suchindan, G.K, Samsuddin M. and Singh
A.D., 1998. "Morphostratigraphic implications ofHolocene coastallandforms along
the northern Kerala. Paper presented in National symposium on Late Quaternary
Geology and sea level changes, held at Cochin University of Science and
Technology, Kochi. (Abstract vol. p 41)
Suchindan, G.K., Samsuddin, M., Ramachandran, K.K. and Haneeshkumar, JI:, 1996.
Holocene coastal landforms along the northern Kerala coast and their implications
011sea level changes. Paper presented in International seminar on Quaternary sea
level variations, shore line displacement and coastal environment. held at Tamil
University Thanjavur. (Abstract vol. p 72)
Ramachandran, K.K., Samsuddin, M., Haneeshkumar, JI: and Suchindan, G.K., 1996.
Organic matter and CaCO accumulation pattern in the shelfsediments offnorthern
3
Kerala southwest India. (Abstract, International Seminar 'GIO' '96 heldat NIO, Goa
during October, 1996. p 103)
111
Singh A.D., Ramachandran, K.K., Samsuddin, M., Nisha, N.R. and Haneesh Kumar, JI:,
2001. Significance ofPteropods in deciphering the late Quaternary sea-level history
along the south western Indian shelf. Geo-marine letters (Springer-Verlag) (in
press).
IV
LISTOF TABLES
Table. 1.1 Length, catchment area and total run offofdifferent rivers in study area
Table. 2.1 The distance, elevation and the width ofstrandlines ofPunjavi transect
Table. 2.2 The distance, elevation and the width ofstrandlines ofOnakkunnu transect
Table. 3.1 Spot height (m), core length (m) and distance from the beach-Onakkunnu and
Punjavi transect
Table. 3.2 Grain size parameters of sediment samples collected from the coastal plain of
Punjavi transect
Table.3.3 Grain size parameters of sediment samples collected from the coastal plain of
Onakkunnu transect
Table.3.4 Percentage abundance of heavy minerals in the strand plain, beach, nearshore
andriver sediments collected from the coastal plain ofPunjavi transect
Table.3.5 Percentage abundance of heavy minerals in the strand plain, beach, nearshore
andriver sediments collected from the coastal plain ofOnakkunnu transect
Table. 4.1 Details regarding distance from the shore (in km), water depth (in m) and core
length (in cm) ofcore samples collected from the continental shelfarea
Table.4.2 Percentage of sand ,silt, clay, CaC0 and organic matter from the continental
3
shelfofPunjavi transect
Table.4.3 Percentage of sand ,silt, clay, CaC0 and organic matter from the continental
3
shelfofOnakkunnu transect
Table. 5.1 Results ofradio-carbon dating
vii
LISTOFFIGURES
Fig. 1.1 Geological map ofthe northern Kerala.
Fig. 1.2 Map ofthe study area showing locations ofPunjavi and Onakkunnu Transects.
Fig. 2.1 The geomorphic map ofPunjavi transect.
Fig. 2.2 The geomorphic map ofOnakkunnu transect.
Fig. 2.3 Transect elevational sections of Punjavi and Onakkunnu transect showing
location and length ofcores.
Fig. 2.4 Cross section ofTransect Iand 11 showing approximate seaward gradients.
Fig. 3.1 Map showing core locations in the coastal plain area ofPunjavi transect.
Fig. 3.2 Map showing core locations in the coastalplain area ofOnakkunnu transect.
Fig. 3.3 Environmental discrimination of sediment samples collected from the coastal
plain area ofPunjavi transect
Fig. 3.4 Environmental discrimination of sediment samples collected from the coastal
plain areaofOnakkunnu transect.
Fig. 3.5 Log of core P-l showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.6 Log of core P-2 showing (A) vertical distribution of size parameters and (B)
lithologyand size frequency distribution.
Fig. 3.7 Log of core P-3 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.8 Log of core P-4 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.9 Log of core P-5 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.10 Log of core P-6 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.11 Log of core P-7 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.12 Log of core P-8 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.13 Log of core P-9 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.14 Log ofcore P-l0showing (A) vertical distribution ofsize parameters and
(B) lithology and size frequency distribution.
Fig. 3.15 Log of core 0-1 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.16 Log of core 0-2 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.17 Log of core 0-3 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.18 Log of core 0-4 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
Fig. 3.19 Log of core 0-5 showing (A) vertical distribution of size parameters and (B)
lithology and size frequency distribution.
viii