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B.Sc. (Honours) Thesis

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Chemical and biological indicators in the sediment record, termed proxies, are often used by scientists to reconstruct past environmental and oceanographic settings, on the scale of tens of thousands to millions of years. Sediment records can help us to understand major climate events and are commonly used to predict future climate fluctuations observed within the proxy record. Sediments are composed of biogenic and terrigenous material. The biogenic components are silica or carbonate based. Siliceous organisms include diatoms and radiolaria, while the carbonaceous organisms include foraminifera, pteropoda, cocolithophora and reef fragments. These biogenic sediments can be used to provide a record of past surface water temperatures, ocean circulation patterns and nutrient availability. Terrigenous material is deposited via aeolian or fluvial mechanisms which provide information about sediment provenance. The purpose of this study is to reconstruct the paleoenvironmental conditions based on sedimentation rates, foraminiferal abundances and sediment composition using carbonate (%) and geochemistry ratios to acquire a better understanding of the processes that dominate the Gulf of Aqaba, located in northern Red Sea. This honours project will investigate a ~4000 year record at a 1-cm resolution on a sediment gravity core recovered from 720 m water depth.

In this study, the term Gulf is referenced to the Gulf of Aqaba.

The Red Sea is a unique area of study for paleoclimatologists due to its warm and saline waters and limited replenishment of sea water from the Indian Ocean. Lack of sea water exchange affects the nutrient input and salinity levels and therefore has significant implications on the biogenic components of the sediment. Because the Red Sea is located in an arid region, the low vegetation cover and surrounding mountains make this region susceptible to flash flooding, resulting in rapid sediment deposition. Mineral dust from the Saharan desert also accounts for a significant proportion of the annual sedimentary input in the Red Sea (Palchan et al., 2013) .

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Pages: 46
Supervisor: Markus Kienast