Northern tributaries along the middle segment of Waiau Toa / Clarence River ( e.g. , Mead Stream , Dee Stream , Branch Stream , Muzzle Stream ) cut through an uplifted , folded and rotated block of limestone and marl that accumulated on the seafloor from the late Cretaceous through the Paleocene and middle Eocene ( 75 – 45 million years ago ) . Exposures of this limestone — the Amuri Limestone — provide some of the most complete records for this time interval of Earth 's history . They have provided important insights to our understanding of the Paleocene-Eocene Thermal Maximum ( PETM ) , Eocene Thermal Maximum 2 ( ETM-2 ) , and other Paleogene hyperthermal events A slip triggered by the 2016 Kaikoura earthquake blocked the Waiau Toa / Clarence River 10 to 12 km from its mouth , with water building up behind the slip . Residents near the river downstream from the slip were evacuated . The river broke through the debris 16 hours after it occurred
2016 Kaikoura earthquake
2016 Kaikoura earthquake
Clarence River (New Zealand)