Ambijacent floodplain

• ambijacent: adjacent on both sides

• flood-plain: ref from The Encyclopædia Britannica vol. XI, 'Geology', 662a: 'In floods the ground inundated on either side of a stream intercepts some part of the detritus, which is then spread over the flood-plain and gradually heightens it. At the same time the stream continues to erode the channel, and ultimately is unable to reach the old flood-plain. It consequently forms a new plain at a lower level, and thus, by degrees, it comes to be flanked on either side by a series of successive terraces or platforms, each of which marks one of its former levels'