Homer, D.L.; Moore, P. 1989 Reading the rocks : a guide to geological features of the Wairarapa Coast. Wellington: Landscape Publications. 64 p..
Abstract: Stretching from Cape Turnagain in the north to Palliser Bay in the south, the Wairarapa Coast is perhaps one of the least well known parts of New Zealand. Its steep headlands, long sandy beaches, rocky shores, reefs, and tiny bays are as impressive and interesting as anywhere in the country. Yet apart from regular visitors to the small holiday resorts of Castlepoint, Riversdale, and Lake Ferry, few people are aware of the many attractions - the unspoilt coastal scenery, windswept forest, seal colonies, and the isolation. And then there are the rocks. The Wairarapa region contains a remarkable record of upheavals which have reshaped the Earth's crust, and nowhere is this better seen than along the coast. In places, 20 million year old sedimentary rocks, originally laid down on the sea floor in a horizontal position, are titled almost on end. The geological forces required to achieve this must have been very great indeed, but for many years there was no adequate explanation for such dramatic bending and buckling of the rocks. We now know it is related to collision and movement along the boundary between two of the enormous plates which make up the Earth's Crust - the Australian and Pacific plates. Not only have the rocks been folded and faulted, they have been severely eroded during advances and retreats of the sea. About 20 million years ago hard greywacke forming the Tararua and Rimutaka ranges was uplifts and debris eroded from the hills was swept far out to sea. Over a long time gravel, sand and mud deposited on the sea floor was transformed into sedimentary rocks which, in turn, were subjected to erosion as a result of sea level changes during the Ice Ages. Geological processes of the past are no different from those occurring today, and the recycling of old rocks to form new ones continues. The evidence of past geological events - earthquakes, volcanic eruptions, and changes in sea level is all there, in the rocks. Like reading a book with some of the pages missing, no one rock outcrop tells the whole story, but it can be pieced together by visiting different places. In this book we have attempted to show the different things that can be seen in the rocks at various localities, and explain what they mean. From a 100-million year old lava flow at Cape Palliser to 6000 year old raised beaches at Turakirae Head, there is one underlying theme to the story - earth's surface is continually on the move! Sixteen of the more spectacular and interesting geological features of the Wairarapa coast are featured, three of which - Castlepoint, Putangirua Pinnacles, and the raised beaches at Turakirae Head are equal to any in the world. These are not simply places of scenic beauty, they also have immense scientific and educational value. By studying the rocks we can learn a great deal about environmental conditions that existed many millions of years ago, and gain an insight into how New Zealand looked long before people set foot on it. Rocks are as much a part of our history as the arrival of the Maori, extinction of the Moa, and the exploits of early European settlers (auths)