The oldest rocks in New Zealand formed during the Palaeozoic Era, ca. 540 million to 350 million years ago, when the area that now makes up New Zealand lay on the margins of the super-continent of Gondwana. Most of the rocks that survive from this time occur in the north-west of South Island - i.e. in the Top of the South. Here, uplifted, underlain and surrounded by the igneous rocks that were intruded during the Devonian and Mesozoic times, they form important parts of the landscape: the Mount Arthur ranges, the Tasman Ranges, the Paparoa Ranges.
Although rocks from all parts of the Palaeozoic are known, many are of volcanoc aroigin or have been heavily metamorphosed by heating and burial, so are unfossiliferous. Fossil-bearing strata are confined to the Buller and Takaka terranes - blocks of sedimentary deposits that were laid down mainly in offshore or deeper water environments, and subsequently heaved and slid into their current position by tectonic forces. These mainly relate to the earlier parts of the Palaeozoic - the Cambrian and Ordovician. Some of the most fascinating fossils are trilobites and graptolites, both of which can be found in the area. But a range of other fossils, including corals, sponges and crinoids are also relatively common. Silurian rocks are known, and some of these contain fossils, but no specimens have yet been collected from them. This page gives a listing of all the taxa of Early Palaeozoic age represented in the collection. To find out more about any individual species, click on the thumbnail. Detailed pages include further images, and a description of the location, key features and background history of the find.