Moore, P.R.; Francis, D.A. 1988 Geology of Kapiti Island, central New Zealand. Lower Hutt: New Zealand Geological Survey. Record / New Zealand Geological Survey 28 23 p.
Abstract: Kapiti Island is composed of an indurated sedimentary (''greywacke'') basement bounded to the east by a zone of phyllonite and overlaid by minor Quaternary sediments. Five main lithotypes are recognised in the basement sequence, including sedimentary breccia and conglomerate. Petrographically the rocks closely resemble Torlesse greywacke of the Wellington area and Kaimanawa Ranges, rather than Pelorus Group rocks of the Marlborough Sounds. Structurally, the basement is dominated by major folds with NE to NNE, subhorizontal axes, and axial planes dipping 70-80 deg.E. Radiolaria extracted from phosphatic concretions indicate a Late Triassic (Norian) age. Quaternary sediments include a remnant of (?) Last (Oturi) Interglacial sandstone, and uplifted beach ridges and terrace deposits. The highest beach ridge may have been raised during the c. 1460 A.D. earthquake, and the modern storm ridge could have been uplifted slightly during the 1855 earthquake. Quaternary tectonic movements also resulted in slight southwestward tilting and possibly some sinistral movement on a major fault along the east side of the island. Correlation of the basement sequence on Kapiti with Torlesse rocks of the Wellington area indicates that the Alpine Fault or its northern extension should be repositioned west of Kapiti Island