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A 3 km long section of the Hooker Glacier near its terminus was studied in 1996 using GPS, tacheometric, and bathymetric surveys, as well as ground penetrating radar and gravity surveys. With reference to sparse surface levels and oblique photos dating back to 1889, the studies indicate that between c. 1915 and 1964 downwasting of an axial strip along the terminal section occurred at a rate of c. 0.7 m/yr. Between 1964 and 1986 the rate increased to 1.0 m/yr. Marginal segments of the glacier near the terminus experienced positive buoyancy from 1982 onwards, which promoted rapid melting. Apparent subaqueous melting rates of c. 9 m/yr occurred between 1986 and 1996 over large stretches of the downmelting terminal area. By 1996, a 1 4 km long sector of the glacier had melted down forming a melt lake (Hooker Lake) with a volume of c. 40 × 10 6 m 3 covering an area of 0.78 × 10 6 m 2. A maximum water depth of 135 m was measured near the retreating glacier front where the ice wall descends as a vertical cliff to the lake bottom and temperatures of 0.5°C prevail. Ice thickness measurements by radar surveys along profiles 1.7 and 3.0 km C97051

Previous stratigraphic and tectonic studies of Coromandel Peninsula, New Zealand, have defined regionally significant structures, including calderas, of Miocene age. A new gravity map of the area reveals significant details not seen in the earlier geophysical surveys. Results from a new low-level aeromagnetic survey and from two new magnetotelluric resistivity soundings help interpret the volcanic structures. 2-D/2.5-D models are used to visualise the internal structure.