Evolution of Cretaceous to Eocene alluvial and carbonate platform sequences in central and south Jordan

ABSTRACT The Cretaceous to Eocene succession in central and south Jordan is characterised by passive continental margin depositional sequences, which pass upward from alluvial/paralic to carbonate shelf and pelagic ramp settings. Detailed section logging and outcrop mapping have produced robust lithostratigraphic and lithofacies schemes that can be correlated throughout the region and in the subsurface. These schemes are set in a sequence-stratigraphic context in relation to the evolution sedimentation on the Arabian and Levant plates. Three major megasequences are described (Kurnub, Ajlun and Belqa), and these are further subdivided into large-scale depositional sequences separated by regional sequence boundaries that represent maximum flooding surfaces. There is close correspondence between maximum flooding surfaces recording major sea-level rise with those derived for the Arabian and Levant plates, although there are some discrepancies with the precise timing of global sea-level fluctuations. An upward change from braided to meandering stream fluvial environments in central and south Jordan during the Early Cretaceous, reflects a decreasing geomorphological gradient of the alluvial plain, declining siliciclastic sediment flux, and increased floodplain accommodation, associated with a regional Late Albian (second-order) rise in relative sea-level. The Late Albian to Early Cenomanian marine transgression across the coastal alluvial plain marks a major sequence boundary. During Cenomanian to Turonian times a rimmed carbonate-shelf was established, characterised by skeletal carbonates showing small-scale, upward-shallowing cycles (fourth- to fifth-order parasequences) ranging from subtidal to intertidal facies, arranged into parasequence sets. Rimmed carbonate shelf sequences pass laterally to coeval coastal/alluvial plain facies to the south and east. Eustatic (third-order) fluctuations in relative sea level during the Cenomanian and Early Turonian resulted in deposition of ammonite-rich wackestones and organic-rich marls, during high sea-level stands (maximum flooding surfaces). Progradational sabkha/salina facies passing landwards to fluvial siliciclastics were deposited during an Early Turonian sea-level low stand, marks a regional sequence boundary, above which a highstand carbonate platform was established. A second-order, regional rise in sea level and marine transgression during the Early Coniacian marks a Type 2 sequence boundary, and subsequent drowning of the rimmed carbonate shelf by Late Coniacian times. Sedimentation during the Santonian to Maastrichtian was characterised by a hemi-pelagic chalk-chert-phosphorite lithofacies association, deposited in shallow to moderate water depths on a homoclinal ramp setting, although thicker coeval sequences were deposited in extensional rifts. The marked change in sedimentation from rimmed carbonate shelf to pelagic ramp is attributed to Neo-Tethyan mid-oceanic rifting, tilting, intracratonic deformation and subsidence of the platform; this is reflected in changes in biogenic productivity and ocean currents. Oceanic upwelling and high organic productivity resulted in the deposition of phosphorite together with giant oyster banks, the latter developing within oxygenated wave-base on the inner ramp. Chalk hardgrounds, sub-marine erosion surfaces, and gravitational slump folds indicate depositional hiatus and tectonic instability on the ramp. In the Early Maastrichtian, deeper-water chalk-marl, locally organic-rich, was deposited in density-stratified, anoxic basins, that were partly fault controlled. Pulsatory marine onlap (highstand sequences) during the Eocene is manifested in pelagic chalk and chert with a paucity of benthic macro-fauna, indicating a highly stressed, possibly hypersaline, and density-stratified water column. Comparison with global and regional relative sea-level curves enable regionally induced tectonic factors (hinterland uplift and ocean spreading) to be deduced, against a background of global sea-level rise, changing oceanic chemistry/productivity and climatic change.

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The biostratigraphic record of Cretaceous to Paleogene tectono-eustatic relative sea-level change in Jamaica

10.31233/osf.io/m5uzk ◽

2018 ◽

Author(s):

David Patrick Gold ◽

James P. G. Fenton ◽

Manuel Casas-Gallego ◽

Vibor Novak ◽

Irene Pérez-Rodríguez ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Carbonate Platform ◽

Caribbean Region ◽

Level Curve ◽

Relative Sea Level ◽

Carbonate Production ◽

Platform Drowning ◽

Relative Sea Level Rise ◽

Strong Control

The island of Jamaica forms the northern extent of the Nicaraguan Rise, an elongate linear tectonic feature stretching as far as Honduras and Nicaragua to the south. Uplift and subaerial exposure of Jamaica during the Neogene has made the island rare within the Caribbean region, as it is the only area where rocks of the Nicaraguan Rise are exposed on land. Biostratigraphic dating and palaeoenvironmental interpretations using larger benthic foraminifera, supplemented by planktonic foraminifera, nannopalaeontology and palynology of outcrop, well and corehole samples has enabled the creation of a regional relative sea-level curve through identification of several depositional sequences. This study recognises ten unconformity-bounded transgressive-regressive sequences which record a complete cycle of relative sea level rise and fall. Sequences are recognised in the Early to ‘Middle’ Cretaceous (EKTR1), Coniacian-Santonian (STR1), Campanian (CTR1), Maastrichtian (MTR1-2), Paleocene-Early Eocene (PETR1), Eocene (YTR1-3) and Late Eocene-Oligocene (WTR1). These transgressive-regressive cycles represent second to fourth order sequences, although most tie with globally recognised third order sequences. Comparisons of the Jamaican relative sea-level curve with other published global mean sea-level curves show that local tectonics exerts a strong control on the deposition of sedimentary sequences in Jamaica. Large unconformities (duration >1 Ma) are related to significant regional tectonic events, with minor overprint of a global eustatic signal, while smaller unconformities (duration <1 Ma) are produced by global eustatic trends. The relatively low rates of relative sea-level rise calculated from the regional relative sea-level curve indicate that carbonate production rates were able to keep pace with the rate of relative sea-level rise accounting for the thick successions of Maastrichtian carbonates and those of the Yellow and White Limestone Groups. Carbonate platform drowning within the White Limestone Group during the Oligocene to Miocene is attributed to environmental deterioration given the low rates of relative sea-level rise.

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Assessment of Sea Level Rise at West Coast of Portugal Mainland and Its Projection for the 21st Century

10.20944/preprints201902.0113.v1 ◽

2019 ◽

Author(s):

Carlos Antunes

Keyword(s):

Time Series ◽

Sea Level Rise ◽

Sea Level ◽

21St Century ◽

West Coast ◽

Satellite Altimetry ◽

Tide Gauge ◽

The West ◽

Relative Sea Level ◽

Global Sea Level

Data collected at the Cascais tide gauge, located on the west coast of Portugal Mainland, have been analyzed and sea level rise rates have been updated. Based on a bootstrapping linear regression model and on polynomial adjustments, time series are used to calculate different empirical projections for the 21st century sea level rise, by estimating the initial velocity and its corresponding acceleration. The results are consistent to an accelerated sea level rise, showing evidence of a faster rise than previous century estimates. Based on different numerical methods of second order polynomial fitting, it is possible to build a set of projection models of relative sea level rise. Appling the same methods to regional sea level anomaly from satellite altimetry, additional projections are also built with good consistency. Both data sets, tide gauge and satellite altimetry data, enabled the development of an ensemble of projection models. The relative sea level rise projections are crucial for national coastal planning and management since extreme sea level scenarios can potentially cause erosion and flooding. Based on absolute vertical velocities obtained by integrating global sea level models, neo-tectonic studies and permanent Global Positioning System (GPS) station time series, it is possible to transform relative into absolute sea level rise scenarios, and vice-versa, allowing the generation of absolute sea level rise projection curves and its comparison with already established global projections. The sea level rise observed at the Cascais tide gauge has always shown a significant correlation with global sea level rise observations, evidencing relatively low rates of composed vertical land velocity from tectonic and post-glacial isostatic adjustment, and residual synoptic regional dynamic effects rather than a trend. An ensemble of sea level projection models for the 21st century is proposed with its corresponding probability density function, both for relative and absolute sea level rise for the west coast of Portugal Mainland.

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Redating the earliest evidence of the mid-Holocene relative sea-level highstand in Australia and implications for global sea-level rise

PLoS ONE ◽

10.1371/journal.pone.0218430 ◽

2019 ◽

Vol 14 (7) ◽

pp. e0218430 ◽

Cited By ~ 4

Author(s):

Amy J. Dougherty ◽

Zoë A. Thomas ◽

Christopher Fogwill ◽

Alan Hogg ◽

Jonathan Palmer ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Relative Sea Level ◽

Global Sea Level

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No evidence from the eastern Mediterranean for a MIS 5e double peak sea-level highstand

Quaternary Research ◽

10.1017/qua.2017.111 ◽

2018 ◽

Vol 89 (2) ◽

pp. 505-510 ◽

Cited By ~ 1

Author(s):

Barbara Mauz ◽

Zhixiong Shen ◽

Noureddine Elmejdoub ◽

Giorgio Spada

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Eastern Mediterranean ◽

Small Scale ◽

Double Peak ◽

Oxygen Isotope Stage ◽

Average Value ◽

Global Sea Level ◽

Facies Succession ◽

Mis 5E

AbstractTo understand past and future sea-level variability, it is important to know if during an interglacial the eustatic sea level is constant or oscillates by several meters around an average value. Several field sites within and outside the tropics have been interpreted to suggest such oscillations during Marine Oxygen Isotope Stage (MIS) 5e (129–116 ka). Here, we present our analysis of one such non-tropical site, Hergla, where a facies succession indicates two foreshore deposits above each other, previously interpreted as MIS 5e sea-level highstand amplified by a second rise. Our study, based on field, microfacies, and optical age Bayesian statistics shows a sea-level rise forming the upper foreshore strata that coincided with the global sea-level rise of the MIS 5a interstadial. The site does therefore not provide evidence for the MIS 5e double peak. We conclude from our analysis that the facies-based proxy is insensitive to small-scale sea-level oscillation. Likewise, uncertainties associated with age estimates are too large to robustly infer a short-term sea-level change.

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A global analysis of subsidence, relative sea-level change and coastal flood exposure

10.5194/egusphere-egu21-14985 ◽

2021 ◽

Author(s):

Daniel Lincke ◽

Robert J. Nicholls ◽

Jochen Hinkel ◽

Sally Brown ◽

Athanasios T. Vafeidis ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Global Analysis ◽

Relative Sea Level ◽

Sea Levels ◽

Coastal Flood ◽

Global Issue ◽

Flood Exposure ◽

Relative Sea Level Rise ◽

Global Sea Level

<p>Climate-induced sea-level rise and vertical land movements, including natural and human-induced subsidence in sedimentary coastal lowlands, combine to change relative sea levels around the world's coast. Global-average coastal relative sea-level rise was 2.5 mm/yr over the last two decades. However, as coastal inhabitants are preferentially located in subsiding locations, they experience an average relative sea-level rise up to four times faster at 7.8 to 9.9 mm/yr. This first global quantification of relative sea-level rise shows that the resulting impacts, and adaptation needs are much higher than reported global sea-level rise measurements would suggest. Hence, coastal subsidence is an important global issue that needs more assessment and action. In particular, human-induced subsidence in and surrounding coastal cities can be rapidly reduced with appropriate policy measures for groundwater utilization and drainage. This offers substantial and rapid benefits in terms of reducing growth of coastal flood exposure due to relative sea-level rise.</p>

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Sedimentation strategies provide effective but limited mitigation of relative sea-level rise in the Mekong delta

Communications Earth & Environment ◽

10.1038/s43247-021-00331-3 ◽

2022 ◽

Vol 3 (1) ◽

Author(s):

Frances E. Dunn ◽

Philip S. J. Minderhoud

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Anthropogenic Activities ◽

Mekong Delta ◽

Relative Sea Level ◽

Sediment Delivery ◽

Limited Effectiveness ◽

Relative Sea Level Rise ◽

Present Context ◽

Global Sea Level

AbstractThe Mekong delta is experiencing rapid environmental change due to anthropogenic activities causing accelerated subsidence, sea-level rise and sediment starvation. Consequentially, the delta is rapidly losing elevation relative to sea level. Designating specific areas for sedimentation is a suggested strategy to encourage elevation-building with nature in deltas. We combined projections of extraction-induced subsidence, natural compaction and global sea-level rise with new projections of fluvial sediment delivery to evaluate the potential effectiveness of sedimentation strategies in the Mekong delta to 2050. Our results reveal that with current rates of subsidence and sediment starvation, fluvial sediments alone can only preserve elevation locally, even under optimistic assumptions, and organic sedimentation could potentially assume a larger role. While sedimentation strategies alone have limited effectiveness in the present context, combined with enhanced organic matter retention and interventions reducing anthropogenic-accelerated subsidence, they can considerably delay future relative sea-level rise, buying the delta crucial time to adapt.

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Assessment of Sea Level Rise at West Coast of Portugal Mainland and Its Projection for the 21st Century

Journal of Marine Science and Engineering ◽

10.3390/jmse7030061 ◽

2019 ◽

Vol 7 (3) ◽

pp. 61 ◽

Cited By ~ 5

Author(s):

Carlos Antunes

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

21St Century ◽

West Coast ◽

Satellite Altimetry ◽

Tide Gauge ◽

Relative Sea Level ◽

Mean Sea Level ◽

Relative Sea Level Rise ◽

Global Sea Level

Based on the updated relative sea level rise rates, 21st-century projections are made for the west coast of Portugal Mainland. The mean sea level from Cascais tide gauge and North Atlantic satellite altimetry data have been analyzed. Through bootstrapping linear regression and polynomial adjustments, mean sea level time series were used to calculate different empirical projections for sea level rise, by estimating the initial velocity and its corresponding acceleration. The results are consistent with an accelerated sea level rise, showing evidence of a faster rise than previous century estimates. Based on different numerical methods of second order polynomial fitting, it is possible to build a set of projection models of relative sea level rise. Applying the same methods to regional sea level anomaly from satellite altimetry, additional projections are also built with good consistency. Both data sets, tide gauge and satellite altimetry data, enabled the development of an ensemble of projection models. The relative sea level rise projections are crucial for national coastal planning and management since extreme sea level scenarios can potentially cause erosion and flooding. Based on absolute vertical velocities obtained by integrating global sea level models, neo-tectonic studies, and permanent Global Positioning System (GPS) station time series, it is possible to transform relative into absolute sea level rise scenarios, and vice-versa, allowing the generation of absolute sea level rise projection curves and its comparison with already established global projections. The sea level rise observed at the Cascais tide gauge has always shown a significant correlation with global sea level rise observations, evidencing relatively low rates of vertical land velocity and residual synoptic regional dynamic effects. An ensemble of sea level projection models for the 21st century is proposed with its corresponding probability density function, both for relative and absolute sea level rise for the west coast of Portugal Mainland. A mean sea level rise of 1.14 m was obtained for the epoch of 2100, with a likely range of 95% of probability between 0.39 m and 1.89 m.

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Climate Change and Changing Coasts

The Korean Journal of International and Comparative Law ◽

10.1163/22134484-12340078 ◽

2017 ◽

Vol 5 (1) ◽

pp. 36-60 ◽

Cited By ~ 1

Author(s):

Clive Schofield

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Climate Change Impacts ◽

Coastal Ecosystems ◽

Small Island ◽

Small Island Developing States ◽

Relative Sea Level ◽

The Pacific ◽

Global Sea Level

Sea level rise has provoked widespread concerns that low-lying parts of coastal States including parts or even the entirety of small island developing States face a looming threat of erosion and inundation. Concerns over the potential impacts of sea level rise on the location of baselines along the coast and therefore on the scope of national claims to maritime jurisdiction have also been raised. The article outlines climate change impacts on the oceans before briefly reviewing projections of sea level rise. A number of the complexities and uncertainties which make prediction of the scale and speed of global sea level rise problematic are highlighted. The importance of assessing relative sea level against the contrasting responses of coasts with diverse geophysical characteristics and distinct coastal ecosystems is emphasised. Potential impacts on island coastlines in the Pacific are then considered and implications maritime claims discussed.

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Submergence, nutrient enrichment, and tropical storm impacts on Spartina alterniflora in the microtidal northern Gulf of Mexico

Marine Ecology Progress Series ◽

10.3354/meps13342 ◽

2020 ◽

Vol 644 ◽

pp. 33-45

Author(s):

JM Hill ◽

PS Petraitis ◽

KL Heck

Keyword(s):

Gulf Of Mexico ◽

Sea Level Rise ◽

Sea Level ◽

Spartina Alterniflora ◽

Anthropogenic Impacts ◽

Interactive Effects ◽

Relative Sea Level ◽

Hurricane Disturbance ◽

Submergence Stress ◽

Relative Sea Level Rise

Salt marshes face chronic anthropogenic impacts such as relative sea level rise and eutrophication, as well as acute disturbances from tropical storms that can affect the productivity of these important communities. However, it is not well understood how marshes already subjected to eutrophication and sea level rise will respond to added effects of episodic storms such as hurricanes. We examined the interactive effects of nutrient addition, sea level rise, and a hurricane on the growth, biomass accumulation, and resilience of the saltmarsh cordgrass Spartina alterniflora in the Gulf of Mexico. In a microtidal marsh, we manipulated nutrient levels and submergence using marsh organs in which cordgrasses were planted at differing intertidal elevations and measured the impacts of Hurricane Isaac, which occurred during the experiment. Prior to the hurricane, grasses at intermediate and high elevations increased in abundance. After the hurricane, all treatments lost approximately 50% of their shoots, demonstrating that added nutrients and elevation did not provide resistance to hurricane disturbance. At the end of the experiment, only the highest elevations had been resilient to the hurricane, with increased above- and belowground growth. Added nutrients provided a modest increase in above- and belowground growth, but only at the highest elevations, suggesting that only elevation will enhance resilience to hurricane disturbance. These results empirically demonstrate that S. alterniflora in microtidal locations already subjected to submergence stress is less able to recover from storm disturbance and suggests we may be underestimating the loss of northern Gulf Coast marshes due to relative sea level rise.

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