Various Dating And Correlating Techniques To Determine The Age Of A Marine Terrace

Various dating and correlating techniques can be used to determine the age of a marine terrace. Firstly correlational data can be recorded using techniques such as the biostratigraphical approach which analyses the remains of organic substances such as foraminifera, shells and mollusc can display indication of sedimentation thus proposing approximate water depth and giving relative age (Shinn 1969). Using a morphostratigraphical approach focuses on the altitude to distinguish the age of a terrace, attributing each terrace to an uplift phase. Cantalamessa et. al (2004) states that assuming paleo-sea at the southern coast of Cabo San Lorenzo level was similar to that of present day during the peak of each marine transgression and the uplift

Eustatic oscillations can cause transgression and regression events. A transgressions is caused increase in sea level, on a global scale this can be cause by transition between a glacial and interglacial period, the warming of the climate leads ice-melt. Where a regression can occur for the same reason, as the climate warms and a glacier melts on top of a localised land mass this can cause an isostatic rebound, allowing the terrace to slowly rise up. As stated earlier climate change affects the development of present day landforms due to global warming, resultant of orbital eccentricity. Orbital eccentricity is the earth's orbit around the sun, as it changes its approach changes from perihelion to aphelion the duration of the seasons will increase, meaning longer summers and winters, which will again alter eustatic oscillations. Tectonics strongly influences the development of a marine terrace and where it forms, involving isostatic uplift of continental crust include their coastline. Depending on the type of orogeny, such as an convergent boundary, the subduction of one plate beneath the other leads to tectonic uplift of the other.