The age of a river is difficult to determine. Generally, the age is estimated based upon which mountains are the source of the river, the age of any mountains it dissects, the sea or ocean to which it eventually outflows, and where it forms its delta. For instance, if a river dissects a mountain range, then this often means the river existed before the mountain range rose.
Each of these factors can make a final contribution in determining the age of a river. Below follows an incomplete list of rivers older than 1 Ma (One million years = 1,000,000 years).
Continent color key | |||||
---|---|---|---|---|---|
Africa | Asia | Oceania | Europe | North America | South America |
River | Age (Ma) | Outflow | Most significant criterion for the age | |
---|---|---|---|---|
1. | 380 | North Sea | Paleozoic, dissects the Ardennes during the Hercynian | |
2. | 350-400 | Lake Eyre (intermittent) |
Predates the Alice Springs Orogeny; many other rivers in the Northern Territory are of a similar age | |
2. |
(Chang Jiang) |
365 | East China Sea | Crosses Paleozoic and Mesozoic mountains |
3. |
(Kanawha River)
|
300 | Kanawha River | Dissects the Appalachian Mountains |
4. | Susquehanna River | 300 | Chesapeake Bay | Dissects the Appalachian Mountains |
5. | Nile | 250 | Mediterranean Sea | Mesozoic |
6. | Rhine | 240 | North Sea | Triassic, maybe older because of the Hercynian; not the Eocene with the Alps, nor the Miocene with the Upper Rhine Graben |
7. | Save | 205 | Indian Ocean | Formed during rifting when Gondwana broke up. |
8. | Amazon | 200 | Atlantic Ocean | Jurassic, but it seems to have flowed in the opposite direction as an extension of the Congo, i.e. long before the formation of Andes |
9. | Amur | 125 | Sea of Okhotsk | Known to be at least Cretaceous in age, but crosses mountains even older |
10. | Macleay River | 80 | Tasman Sea | Predates uplift of Great Escarpment |
11. | Murrumbidgee River | 75 | Murray River | Predates uplift of Australian Alps |
12. | Colorado (Western U.S.) |
75 | Gulf of California | Uplift during Laramide orogeny, see Geology of the Grand Canyon area |
13. | Thames | 58 | North Sea | Late Palaeocene Period Thanetian Stage. |
14. |
(Sindhu) |
45 | Arabian Sea | Source in the Himalayas and Karakoram Mountains |
Courtesy : Wikipedia
very informative. Thanks for wonderfully compiled info
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Thank you 🙂
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