marine geology

Spatial variability of wave signatures and profile morphotypes of beaches in estuaries and bays across different tidal regimes

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Map showing the Ría de Vigo and Pittwater estuaries with the locations of eight studied beaches and wave measurement sites.

This study compares sandy beaches within estuaries and bays in a microtidal system (Pittwater, Sydney) and a mesotidal system (Ría de Vigo, Spain) to understand how waves, tides and sediment shape beach profiles. Swell waves dominate wave energy in both settings, but their relative contribution decreases further from the estuary entrance, where wind and infragravity … Read more…

Nature Communications: Deep-sea hiatus record reveals orbital pacing by 2.4 Myr eccentricity grand cycles

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Astronomical forcing of Earth’s climate is embedded in the rhythms of stratigraphic records, most famously as short-period (10^4–10^5 year) Milankovitch cycles. Astronomical grand cycles with periods of millions of years also modulate climate variability but have been detected in relatively few proxy records. Here, we apply spectral analysis to a dataset of Cenozoic deep-sea hiatuses … Read more…

Marine Geology: Tidal dynamics drive ooid formation in the Capricorn Channel since the Last Glacial Maximum

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Relative sea-level changes can dramatically alter coastal geomorphology and coastlines, which, in turn, can fundamentally alter tidal regimes. The Great Barrier Reef (GBR) has undergone around 120 m of relative sea level (RSL) rise since the Last Glacial Maximum, ∼20,000 years ago (ka). Ooid grains (sand sized carbonate sediment) that formed in shallow water (>5 m depth) … Read more…