The Neogene in New Zealand is mainly distributed throughout seven basins of marine sedimentation. Some of these basins have formed in the tectonically mobile setting of the Indian-Pacific plate junction. Consequently, they vary greatly in stratigraphic and sedimentary character and especially in the thickness of the sedimentary formations which are considerable in places (eg. 7000 m of Lower Miocene-Lower Pleistocene sandstone and mudstone, northern part of East Coast Basin). Shelf limestones predominate in the Upper Oligocene and basal Miocene but thereafter sandy and muddy facies are more usual. Coquinas are prominent in the Pliocene of the East Coast Basin having formed as extensive barnacle banks along the margins of a narrow seaway during repeated movements of the plate boundary zone. Correlations are usually expressed in New Zealand marine stages based principally on foraminifera in the Miocene and Lower Pliocene and on mollusca in the Upper Pliocene and Pleistocene in stratotypes and reference sections.