Begg, J.G. 1993 Completion report, stratigraphic drillhole UHS-1, Trentham, Upper Hutt, New Zealand. Lower Hutt: Institute of Geological & Nuclear Sciences Institute of Geological & Nuclear Sciences science report 93/15 21 p.
Abstract: A stratigraphic drillhole at Trentham Memorial Park was drilled to detail the stratigraphy, chronology, and geological history of the Upper Hutt basin. The drillhole penetrated to a depth of 68.9 m before drilling was stopped. Six stratigraphic units are recorded from the hole: unit 1: c. 1.5 m of soil and fill; unit 2: from c. 1.5 to c. 30 m, mostly coarse grey-blue gravel; unit 3: from c. 30 to c. 34 m, largely coarse, rust-stained gravel; unit 4: from c. 34 to 51.5 m, grey, slightly weathered mostly coarse gravel, unit 5: from 51.5 to 68 m, soft to very stiff, blue-grey silt, silty clay, clayey silt and minor peat; and unit 6: 68 to 68.9 m, slightly weathered, grey coarse gravel. Depositional environments of units 2 to 4, and 6 are fluvial, and unit 5 is thought to be largely the result of swamp deposition. A Late Quaternary age is assumed for these sediments until palynological analysis and radiocarbon dating results are known. The unforeseen high costs of penetrating thick, loose, water-saturated Quaternary gravels caused premature cessation of drilling. (auth)