Coastal Response to Changes in Sea Level Since the Last 4500 BP On the East Coast of Tamil Nadu, India

Geomorphology, clay mineral composition, and radiocarbon dates from Muttukadu to Marakkanam estuaries and the tidal zone along the east coast of Tamil Nadu, India, have been used to reconstruct coastal evolution between approximately 4500 and 1100 B P. Formation of alternate oyster beds with intervening tidal clay units indicate fluctuation in the sea level may be a consequence of changes in the Mid-Holocene sedimentation pattern and coastal configuration. 14C dates from Muttukadu indicate a rapid relative sea-level rise (RSL) subsequent to 3500 BP and tidal flat sedimentation between 3475 and 3145 BP. Marine conditions along the east coast area returned around 1900 B P. Comparison of dates with other sites, e.g. Muttukadu, Mammallapuram, and Marakkanam, points toward short removal of marine conditions, ample sediment supplies in the tidal zones, and neotectonic activity. Reactivation of the north–south trending fault line occurred not earlier than approximately 1050 B P. Our study indicates that Middle to Late Holocene coastal sedimentation and the chronology of the tidal zone formation have been strongly influenced by local factors. These have provided considerable scope for internal reorganization with changing coastal processes.

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Postglacial relative sea-level change, Port au Port area, west Newfoundland

Canadian Journal of Earth Sciences ◽

10.1139/e85-107 ◽

1985 ◽

Vol 22 (7) ◽

pp. 1039-1047 ◽

Cited By ~ 23

Author(s):

I. A. Brookes ◽

D. B. Scott ◽

J. H. McAndrews

Keyword(s):

Sea Level ◽

Late Holocene ◽

High Water ◽

Relative Sea Level ◽

Radiocarbon Dates ◽

Ice Load ◽

Bay Area ◽

Port Area ◽

Minimum Age ◽

Late Wisconsinan

We first report pollen and foraminifera analyses and radiocarbon dates from two cores taken from salt-marsh deposits bordering Port au Port Bay, southwestern Newfoundland. Results show that relative sea level (RSL) stood at 2.8 m below present higher high-water level (HHWL) at 2770 ± 300 years BP and at −1.8 m at 2365 ± 175 years BP at the core sites. They permit calculation of a rate of late Holocene RSL change from western Newfoundland. We then report other available dates bearing on the earlier RSL record of this area.A date of 5800 ± 200 years BP fixes the age of minimum RSL in Port au Port Bay at 11–14 m below present. A date of 9350 ± 120 years BP from St. George's provides a minimum age for the passage of sea level below present there. A date of 12 600 ± 140 years BP from Stephenville fixes a sea level at 29 m above present, whereas one of 13 600 ± 110 years BP from Abrahams Cove dates the marine limit at 44 m. These geographically restricted data closely constrain a curve of postglacial RSL change in the Port au Port Bay – northern St. George's Bay area. The form of the curve supports a recent model predicting sea-level response to wastage of a limited late Wisconsinan ice load in the wider region.

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Interpretation of radiocarbon dates from the upper surface of late-Holocene peat layers in coastal lowlands

The Holocene ◽

10.1191/0959683606hl895ra ◽

2006 ◽

Vol 16 (1) ◽

pp. 51-61 ◽

Cited By ~ 19

Author(s):

M. P. Waller ◽

A. J. Long ◽

J. E. Schofield

Keyword(s):

Plant Communities ◽

Late Holocene ◽

A Priori ◽

Radiocarbon Dates ◽

Coastal Lowland ◽

The North ◽

Clastic Sediments ◽

The North Sea ◽

Underlying Processes ◽

Coastal Lowlands

Marine/brackish clastic sediments replace freshwater peats in the stratigraphic column of many coastal lowland areas bordering the North Sea during the late Holocene. Radiocarbon dates are routinely used to provide a chronology for this shift. We examine the assumptions underpinning this approach. The results of investigations from 13 sites in the Rye area of Romney Marsh, southeast England, are reported. Dates from apparently gradational contacts of a highly humified, laterally persistent, peat layer range from 3170-2840 cal. yr BP to 1290-1050 cal. yr BP. Multiple inundations or prolonged gradual inundation are nevertheless rejected, as discrete post-peat bodies of sediment are absent and because peat growth appears to have slowed-down or ceased at many sites in advance of inundation. Additionally in the Rye area, sharp contacts are widespread and the pollen assemblages rarely indicate the occurrence of transitional plant communities. A review of the dating evidence from other coastal lowland regions reveals that multiple dating of the upper surface of peat beds invariably produces diachronous results. As a consequence time transgressive processes feature prominently as causal mechanisms underlying this shift. However, many of the dating difficulties recognized in the Rye area appear to apply to other regions. We conclude that radiocarbon dates from the upper surface of peat layers should in most instances only be regarded as limiting ages for the deposition of the overlying clastic sediments. New chronologies need to be built without a priori assumptions as to the underlying processes, ideally through the direct dating of the clastic sediments.

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Depositional Setting and Cementation Pattern of Al-Mejarma Beachrocks, Saudi Arabia: A Proxy for the Late Quaternary Red Sea Coastal Evolution

Journal of Marine Science and Engineering ◽

10.3390/jmse9091012 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1012

Author(s):

Ibrahim Ghandour ◽

Hamad Al-Washmi ◽

Athar Khan ◽

Ammar Mannaa ◽

Mohammed Aljahdali ◽

...

Keyword(s):

Saudi Arabia ◽

Sea Level ◽

Red Sea ◽

Late Holocene ◽

High Energy ◽

Coarse Grained ◽

Coastal Evolution ◽

Depositional Setting ◽

Middle And Late Holocene ◽

Holocene Sea Level

This study utilizes lithofacies characteristics, petrographic, XRD, and stable isotope data of Al-Mejarma beachrocks, Red Sea, Saudi Arabia, to interpret its depositional setting, origin of cement, and coastal evolution. The beachrock is 1.15 m thick, medium to very coarse-grained sandstone with scattered granules. It shows massive to graded bedding, horizontal, ripple, and shore parallel to slightly oblique planar cross-laminations, with a remarkable absence of bioturbation. It was deposited by shore-parallel longshore currents in a relatively high-energy beach environment. The framework comprises quartz, feldspars, and lithic fragments admixed with biogenic remains of algae, mollusca, foraminifera, corals, and echinoids. They are cemented by high magnesium calcite in the form of isopachous rims and pore-filling blades, and rarely, as a meniscus bridge. The mean values of δ18OVPDB and δ13CVPDB are 0.44‰ and 3.65‰, respectively, suggesting a seawater origin for the cement. The framework composition, facies geometry, and association with back-barrier lagoon impose a deposition as a shoreface-beach barrier through two stages corresponding to the middle and late Holocene. The first stage attests landward migrating sediment accumulation and rapid marine cementation. The sediments stored offshore during the early and middle Holocene humid periods migrated landward from offshore and alongshore by onshore waves and longshore drift during the middle and late Holocene sea-level highstand. They were cemented to form beachrock and subsequently emerged as the late Holocene sea-level fell.

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Fluvial Sedimentology and Paleoecology of Holocene Alluvial Deposits, Red River, Manitoba

Géographie physique et Quaternaire ◽

10.7202/032948ar ◽

2007 ◽

Vol 47 (2) ◽

pp. 193-210 ◽

Cited By ~ 8

Author(s):

Erik Nielsen ◽

W. Brian McKillop ◽

Glen G. Conley

Keyword(s):

Late Holocene ◽

Red River ◽

Present Position ◽

Lake Agassiz ◽

Alluvial Deposits ◽

Radiocarbon Dates ◽

The North ◽

Mollusc Species ◽

History Of ◽

Overbank Sedimentation

ABSTRACT Stratigraphie and paleoecological analyses at five sections, together with age determinations based on 19 previously published and 21 new radiocarbon dates, provide a detailed late Holocene history of the Red River, Manitoba. Ecological information, such as age frequency analysis, relative abundance, diversity and association of species was drawn from 19 mollusc species. These data indicate that the Red and Assiniboine rivers cut the valleys they occupy today within a thousand years of the regression of Lake Agassiz. In the south, up to 14 m of alluvium has accumulated during the last 7000 years. A decrease in the sedimentation rate at 1400 BP is coincident with the shift in the position of the Assiniboine from the valley of the La Salle River to its present position. Overbank sedimentation did not start in the northern part of the area until ca. 5200 BP. Initial rapid sedimentation rates in this area are attributed to increased precipitation and a brief eastward excursion of the Assiniboine River into the Red. In spite of increased precipitation, flood frequencies remained low in the north until 1400 BP. Increased overbank sedimentation after 1400 BP is attributed to the northward shift in the position ot the Assiniboine.

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Holocene sea-level history and coastal evolution of the north-western Fenland, eastern England

Proceedings of the Geologists Association ◽

10.1016/j.pgeola.2014.12.001 ◽

2015 ◽

Vol 126 (1) ◽

pp. 72-85 ◽

Cited By ~ 5

Author(s):

David S. Brew ◽

Benjamin P. Horton ◽

Graham Evans ◽

James B. Innes ◽

Ian Shennan

Keyword(s):

Sea Level ◽

Coastal Evolution ◽

The North ◽

North Western ◽

Holocene Sea Level

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Seasonal Variability of Sea Level and Sea-surface Temperature on the North-east Coast of New Zealand

Estuarine Coastal and Shelf Science ◽

10.1006/ecss.1997.0286 ◽

1998 ◽

Vol 46 (2) ◽

pp. 307-318 ◽

Cited By ~ 18

Author(s):

R.G. Bell ◽

D.G. Goring

Keyword(s):

New Zealand ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Sea Level ◽

Seasonal Variability ◽

East Coast ◽

Sea Surface ◽

North East ◽

The North

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Accelerated flooding along the U.S. East Coast: On the impact of sea‐level rise, tides, storms, the Gulf Stream, and the North Atlantic Oscillations

Earth s Future ◽

10.1002/2014ef000252 ◽

2014 ◽

Vol 2 (8) ◽

pp. 362-382 ◽

Cited By ~ 98

Author(s):

Tal Ezer ◽

Larry P. Atkinson

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

North Atlantic ◽

Gulf Stream ◽

East Coast ◽

The North ◽

The North Atlantic ◽

The Impact ◽

The U.S

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Late Holocene Coastal Plain Stratigraphy and Sea-Level History at Hanalei, Kauai, Hawaiian Islands

Quaternary Research ◽

10.1006/qres.1996.0005 ◽

1996 ◽

Vol 45 (1) ◽

pp. 47-58 ◽

Cited By ~ 21

Author(s):

R. Scott Calhoun ◽

Charles H. Fletcher

Keyword(s):

Sea Level ◽

Coastal Plain ◽

Radiocarbon Dating ◽

Late Holocene ◽

Hawaiian Islands ◽

Relative Sea Level ◽

North Shore ◽

The North ◽

And Sea Level ◽

Whole Earth

AbstractFluvial, marine, and mixed fluvial-marine deposition on the coastal plain of Hanalei Bay on the north shore of Kauai, Hawaii, records a middle- to late-Holocene fall of relative sea level. Radiocarbon dating of the regression boundary preserved in the stratigraphy of the coastal plain documents a seaward shift of the shoreline beginning at least 4800–4580 cal yr B.P. and continuing until at least 2160–1940 cal yr B.P. Marine sands stranded in the backshore and coastal plain environment are buried by fluvial floodplain and channel sands, silts, and muds. In places, erosion at the regression contact exposed older marine sands thus increasing the hiatus at the regression disconformity. The shoreline regression is best explained as the result of a fall in relative sea level. The age and elevation of the cored regression boundary at sites that have not been influenced by erosion are consistent with a middle- to late-Holocene highstand of relative sea level as predicted by geophysical models of whole Earth deformation related to deglaciation.

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Late Holocene Sea-Level Change on Rota and Guam, Mariana Islands, and Its Constraint on Geophysical Predictions

Quaternary Research ◽

10.1006/qres.1993.1071 ◽

1993 ◽

Vol 40 (2) ◽

pp. 189-200 ◽

Cited By ~ 20

Author(s):

Hajime Kayanne ◽

Teruaki Ishii ◽

Eiji Matsumoto ◽

Nobuyuki Yonekura

Keyword(s):

Sea Level ◽

Late Holocene ◽

Sea Level Change ◽

Mariana Islands ◽

Present Level ◽

Sea Level Changes ◽

Radiocarbon Dates ◽

Level Change ◽

Sea Level Variations ◽

Holocene Sea Level

AbstractHolocene emergent reefs and notches are well distributed on Rota and Guam. Relative sea-level changes at these islands are reconstructed based on geomorphological observations and borings on present and emergent reefs, together with 54 radiocarbon dates. Sea level rose gradually to a maximum of 1.8 m between 6000 and 4200 yr B.P. and reached its highest level by 4200 yr B.P. on both islands. After 3200 yr B.P. abrupt uplift caused emergence of the reef. By subtracting the tectonic effect, we obtained the sea-level change in the Marianas: sea level reached its present level by 4200 yr B.P. and has remained almost stable since then. Reconstructed late Holocene sea-level change in the Mariana Islands provides constraints on geophysical models of sea-level variations.

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