Question

Choose statements true of transgression and regression. Sort the statements as being true of either transgression or regression.

Transgression: - Coastline migrates inland - Position of beach moves inland - Involved a relative rise in sea level Regression: - Involves a relative fall in sea level

Answer 1

Transgression involves the inland migration of the coastline due to sea level rise, while regression occurs when sea level falls and previously submerged seafloor becomes exposed, moving sediments away from the coastline.

Step-by-step explanation:

The terms transgression and regression refer to changes in sea level relative to the land, which lead to shifts in the position of shorelines and changes in sedimentary deposits. Transgression occurs when the sea level rises relative to the land, causing the coastline to migrate inland, and the position of beaches and associated sedimentary deposits to move landward, often resulting in sediments onlapping toward the coastline as indicated by Walther's Law.

During a regression, the sea level falls relative to the land, leading to areas of previously submerged seafloor being exposed, and sedimentary deposits moving in an offlapping direction away from the coastline. Walther's Law also applies here, suggesting that vertical sediment sequences reflect horizontal environmental shifts.