Inland sea (geology)

Modern inland seas

• The Marmara Sea located in modern day Turkey is a textbook example of an inland sea. It is surrounded by land all around, except where it connects the two Turkish Straits, the Bosphorus and the Dardanelles.
• The Baltic Sea is a brackish inland sea, arguably the largest body of brackish water in the world. The origin of the basin is not clear as there are differing views on the role of erosion and tectonics.
• Hudson Bay, including James Bay at its southern end, reaches within the North American continent from Baffin Island, Nunavut in the north to Quebec, Ontario and Manitoba in the south. The bay shares some similarities with the Gulf of Bothnia in Fennoscandia; it lies in the middle of a shield and it was the centre of an ice sheet during the Quaternary glaciations. However, the origin of both depressions is unrelated to glacier erosion.
• The Seto Inland Sea in Japan is not a true inland sea but rather a body of water separating Honshū, Shikoku, and Kyūshū, three of the four main islands of Japan.

  Former epicontinental seas in Earth's history

• During the Oligocene and Early Miocene large swathes of Patagonia were subject to a marine transgression. The transgression might have temporarily linked the Pacific and Atlantic oceans, as inferred from the findings of marine invertebrate fossils of both Atlantic and Pacific affinity in La Cascada Formation. Connection would have occurred through narrow epicontinental seaways that formed channels in a dissected topography.
• A vast inland sea, the Western Interior Seaway, extended from the Gulf of Mexico deep into present-day Canada during the Cretaceous.
• At the same time, much of the low plains of modern-day northern France and northern Germany were inundated by an inland sea, where the chalk was deposited that gave the Cretaceous Period its name.
• The Amazon, originally emptying into the Pacific, as South America rifted from Africa, found its exit blocked by the rise of the Andes about 15 million years ago. A great inland sea developed, at times draining north through what is now Venezuela before finding its present eastward outlet into the South Atlantic. Gradually this inland sea became a vast freshwater lake and wetlands where sediment flattened its profiles and the marine inhabitants adapted to life in freshwater. Over 20 species of stingray, most closely related to those found in the Pacific Ocean, can be found today in the freshwaters of the Amazon, which is also home to a freshwater dolphin. In 2005, fossilized remains of a giant crocodilian, estimated to have been in length, were discovered in the northern rainforest of Amazonian Peru.
• In Australia, the Eromanga Sea existed during the Cretaceous Period. It covered large swaths of the eastern half of the continent.