PUNAKAIKI, PANCAKE ROCKS
The Pancake Rocks at Dolomite Point, Punakaiki, form a well-known tourist attraction some 30 miles north along the coast road from Greymouth. A track from the road leads through native ferns, pongas, and nikau palms to the coast, where rain and sea water have widened the joints in a well-bedded limestone that dips gently seaward into many deep narrow channels. The remnants survive as narrow ridges and pillars in which the softer layers have been eroded out, leaving the harder layers projecting to give the layered effect from which the rocks take their name. Caves and large open chambers, the largest with a natural bridge, have been carved in the rock by the Tasman Sea, assisted by the explosive effects of air compressed in the joints by the waves. On calm days the running of the sea in the caves and chambers, and the gentle hiss of escaping air are heard, but when it is rough, thunderous booming and rumbling noises accompany geyser-like jets of water and compressed air from the blowholes as the sea rushes in and out of the caves and chambers in its relentless attack on the headland.
by Frederick Ernest Bowen, B.SC.(DURHAM), New Zealand Geological Survey, Otahuhu.