The phrase "ancient riverbed" refers to a place where a river used to flow a very long time ago but is now dry or no longer active.
Sentences with «ancient riverbed»
Rose's team of archaeologists and geologists gathered more than 800 artifacts from ancient riverbeds in the Dhofar Mountains of southern Oman. (sciencemag.org)
These photos painted the Red Planet in an entirely new light, revealing huge volcanoes, giant canyons and what appeared to be the remnants of ancient riverbeds. (space.com)
Soil and conditions are typical of AVAs with alluvial ancient riverbed cobbled clay. (winebusiness.com)