https://creation.com/do-rivers-erode-through-mountains We shall continue our discussions of whether or not YEC claims stand up to scrutiny with an examination of water gaps, which allegedly provide further evidence that the Earth's geological landscape has been shaped by extreme flooding in the relatively recent past. Many rivers, after travelling along a valley, suddenly turn and flow through a narrow gorge that cuts through a mountain range, a ridge, or a plateau. Such gorges are called water gaps . It looks like the river cut the gorge, but how could it? Surely, if the river had carved the landscape slowly over long ages, it would have flowed around the barrier instead of flowing through it. So was the gorge eroded first by something we don’t see happening today? There are many hypotheses for the origin of water gaps based on slow processes of erosion over millions of years. However, these ideas are rarely based on evidence. Thomas Oberlander has many sobering thoughts about research on water gaps: … the question of the origin of geological discordant drainage [water gaps] has almost always been attacked deductively, leading toward conclusions that remain largely within the realm of conjecture ’ (Emphasis added).