नदी की पुरानी धरा, जिससे होकर अब नदी नहीं बहती है, को Paleochannels कहते हैं । आम बोल-चाल की भाषा में इसे छाड़न या छाड़नधर कहते हैं।
A palaeochannel, also spelt paleochannel and also known as palaeovalley or palaeoriver, is a geological term describing a remnant of an inactive river or stream channel that has been filled or buried by younger sediment. The sediments that the ancient channel is cut into or buried by can be unconsolidated, semi-consolidated, consolidated or lithified. The word palaeochannel is formed from the palaeo, meaning "old," and channel. (wiki)
