From a river valley to a ria: Evolution of an incised valley (Ría de Ferrol, north‐west Spain) since the Last Glacial Maximum

Sedimentology ◽  
2019 ◽  
Vol 66 (5) ◽  
pp. 1930-1966 ◽  
Author(s):  
Víctor Cartelle ◽  
Soledad García‐Gil
Keyword(s):  
Last Glacial Maximum ◽  
River Valley ◽  
Glacial Maximum ◽  
Incised Valley ◽  
North West ◽  
Last Glacial ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Sedimentary evolution of a bedrock-conditioned incised valley since the Last Glacial Maximum: the Ría de Arousa (NW Spain)

2020 ◽  
Author(s):  
Víctor Cartelle ◽  
Soledad García-Gil ◽  
Iria García-Moreiras ◽  
Castor Muñoz-Sobrino ◽  
Natalia Martínez-Carreño
Keyword(s):  
Sea Level ◽  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Nw Spain ◽  
Incised Valley ◽  
Last Glacial ◽  
Sedimentary Evolution ◽  
River Mouths ◽  
The Last Glacial Maximum ◽  
The Last Glacial

<p>Coastal sedimentary environments are dynamic systems in continuous change responding to different temporal and spatial scales. Their sedimentary record offers invaluable data to unveil the effect of different drivers, such as relative sea-level rise, on their evolution.</p><p>The Ría de Arousa is located on the Atlantic coast of Galicia (NW Spain) and represents the largest of the so-called “Galician Rias”, with a total area of 230 km2. It corresponds to a mesotidal tide-dominated incised valley characterized by a complex physiography with numerous smaller bays, islands and peninsulas.</p><p>The identification of elements of sedimentary architecture was used to study the sedimentary evolution of this incised valley since the Last Glacial Maximum (ca 20 kyr BP to present). This approach was based on the combined analysis of seismic and sedimentary facies, complemented with radiocarbon, geochemical and pollen data.</p><p>During the lowstand of the Last Glacial Maximum, a river basin occupied the deep axial valley whose physiography was controlled by the rocky basement morphology and the presence of preserved older sedimentary units. The postglacial transgression changed the base level of rivers, flooding the valley and leading to the formation of an estuary. Facies distribution during this phase (Late Pleistocene) was characterized by large tidal sandbanks and sandflats in the outer area and a bayhead delta at the river mouths. As the transgression proceeded, during the Early Holocene, the system evolved into a tide-dominated estuary. Tidal sandbanks and sandflats occupied large extensions in the axis of the valley, flanked by mudflats. The presence of a small group of islands in the middle area of the incised valley gave way to the existence of an ancient strait during most of the postglacial transgression (Late Pleistocene and Holocene), modulating the relative influence of hydrodynamic conditions and probably leading to tidal currents amplification due to the local morphological narrowing. These structural highs favored the formation of a rock-bounded tidal inlet in the middle of the valley, characterized by scarce deposition and erosional processes.</p><p>During the Middle and the Late Holocene, most of the incised valley became drowned, and wave influence increased. A wave ravinement surface is identified, which was developed around 8 cal kyr BP coeval with the initiation of large storm fans associated with rocky barriers.</p><p>Finally, a maximum flooding surface is recognized at ca 5 cal kyr BP while the slow rise of sea level forced river mouths to retreat to its present position and marine processes became dominant in the basin.</p>

Continental/Cordilleran ice interactions: a dominant cause of westward super-elevation of the last glacial maximum continental ice limit in southwestern Alberta, Canada

2001 ◽  
Vol 30 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Edward C. Little ◽  
Lionel E. Jackson ◽  
Thomas S. James ◽  
Stephen R. Hicock ◽  
Elizabeth R. Leboe
Keyword(s):  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Last Glacial ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Reconstructions of the past distribution of Testudo graeca mitochondrial lineages in the Middle East and Transcaucasia support multiple refugia since the Last Glacial Maximum

2021 ◽  
pp. 10-17
Author(s):  
Oguz Turkozan
Keyword(s):  
Middle East ◽  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Testudo Graeca ◽  
Last Glacial ◽  
The Past ◽  
Precipitation Seasonality ◽  
Multiple Refugia ◽  
The Last Glacial Maximum ◽  
The Last Glacial

A cycle of glacial and interglacial periods in the Quaternary caused species’ ranges to expand and contract in response to climatic and environmental changes. During interglacial periods, many species expanded their distribution ranges from refugia into higher elevations and latitudes. In the present work, we projected the responses of the five lineages of Testudo graeca in the Middle East and Transcaucasia as the climate shifted from the Last Glacial Maximum (LGM, Mid – Holocene), to the present. Under the past LGM and Mid-Holocene bioclimatic conditions, models predicted relatively more suitable habitats for some of the lineages. The most significant bioclimatic variables in predicting the present and past potential distribution of clades are the precipitation of the warmest quarter for T. g. armeniaca (95.8 %), precipitation seasonality for T. g. buxtoni (85.0 %), minimum temperature of the coldest month for T. g. ibera (75.4 %), precipitation of the coldest quarter for T. g. terrestris (34.1 %), and the mean temperature of the driest quarter for T. g. zarudyni (88.8 %). Since the LGM, we hypothesise that the ranges of lineages have either expanded (T. g. ibera), contracted (T. g. zarudnyi) or remained stable (T. g. terrestris), and for other two taxa (T. g. armeniaca and T. g. buxtoni) the pattern remains unclear. Our analysis predicts multiple refugia for Testudo during the LGM and supports previous hypotheses about high lineage richness in Anatolia resulting from secondary contact.

WASATCH RANGE, UT GLACIER RECONSTRUCTIONS FOR THE LAST GLACIAL MAXIMUM AND LATEGLACIAL

2017 ◽  
Author(s):  
Brendon J. Quirk ◽  
◽  
Jeffrey R. Moore ◽  
Benjamin J. Laabs ◽  
Mitchell A. Plummer ◽  
...  
Keyword(s):  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Last Glacial ◽  
The Last Glacial Maximum ◽  
The Last Glacial

EXAMINING PALEODRAINAGE EVOLUTION SINCE THE LAST GLACIAL MAXIMUM, NORTHERN CHANNEL ISLANDS, CALIFORNIA, USA

2018 ◽  
Author(s):  
Howasta S. Tahiry ◽  
◽  
Jillian M. Maloney ◽  
Shannon A. Klotsko ◽  
Amy E. Gusick ◽  
...  
Keyword(s):  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Channel Islands ◽  
Last Glacial ◽  
Northern Channel Islands ◽  
The Last Glacial Maximum ◽  
The Last Glacial
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