Bounty Islands Research Articles

A review of the living New Zealand members ofOnithochitonGray, 1847 (Mollusca: Polyplacophora)

Abstract Two taxa belonging to the genus Onithochiton Gray, 1847 are recognised from New Zealand: O. neglectus neglectus de Rochebrune, 1881 and O. neglectus subantarcticus Suter, 1906. Chiton undulatus Quoy & Gaimard, 1835; O. astrolabei and O. filholi de Rochebrune, 1881; O. semisculptus Pilsbry, 1894; O. marmoratus von Wissel, 1904; O. nodosus Suter, 1907; O. opiniosus Iredale & Hull, 1932; and Icoplax chathamensis Dell, 1960 are synonyms of O. neglectus neglectus de Rochebrune, 1881. O. neglectus var. subantarcticus Suter, 1906 is a subspecies of O. neglectus sensu lato. O. neglectus neglectus is redescribed and a lectotype of O. neglectus neglectus is selected from de Rochebrune's syntypes, and figured. O. neglectus subantarcticus Suter, 1906 is separated from O. neglectus sensu stricto on the basis of minor, but geographically stable, differences. Onithochiton is recorded from the Bounty Islands. Onithochiton oliveri Iredale, 1914 from the Kermadec Islands is separated from the New Zealand species on girdle characters.

Parapsyllus magellanicus largificus, a new flea from the Bounty Islands

Abstract Parapsyllus magellanicus largificus subsp. n. (Siphonaptera: Rhopalopsyllidae) is described from specimens found in nests of Salvin's mollymawk, Diomedea cauta salvini (Roths-child), on the Bounty Islands, New Zealand. This is the first record of a flea from this host.

New Zealand fur seals at the Bounty Islands

New Zealand fur seals at the Bounty Islands

New Zealand fur seals at the Bounty Islands

Abstract New Zealand fur seals, Arctocephalus forsteri (Lesson, 1828), at the Bounty Islands (47°45'S, 179°03'E) were virtually annihilated by commercial sealing in the period 1808–1890. Legal protection and the cessation of sealing in 1891 were followed by a slow increase in numbers. Aerial photography is a practical method for monitoring fur seal numbers at the Bounty Islands, where the animals show up clearly on the smooth granite substrate. Low‐level oblique aerial photographs taken between May 1974 and December 1980 have been used to determine the present distribution of seal colonies and estimate the numbers ashore. The number of seals (excluding new‐born pups) ashore on 29 December 1980 was estimated as 6700, and the number of pups as 3280, from sample counts of 3050 and 477 respectively. Calculations based on estimated pup production, and published figures on immature mortality, sex ratio, and pregnancy rate from other fur seal populations, suggest that the total population of the Bounty Islands i...

Exploration Results Offshore South New Zealand: ABSTRACT

Some significant data are here revealed for the first time, covering the 10-year oil exploration program of New Zealand's vast South Island submerged plateau. A 250,000-sq mi (650,000 sq ha.), Texas-sized group of licenses was taken by Hunt International Petroleum Co. in 1968 and 1969. About 26,000 line-mi (41,600 line-km) of marine, 12-fold seismic survey, was completed over a 4-year period. Much of the survey extended to 4,500-ft (1,350 m) water depth. Tectonics are controlled by the separation and splay of New Zealand's backbone Alpine fault system as it swings southeastward across the Campbell Plateau toward Bounty Island and the Antipodes. Basement is of Paleozoic age. Lower Mesozoic sediments resulting from orogenies and plate shifts are relative to Mesozoic Gondwana breakup. Six previously unknown Tertiary basins, large by basin standards, were discovered. The interpretive mapping revealed 30 to 40 giant to supergiant anticlinal structures and an equal number of normal ones, mostly in water depths exceeding 2,000 ft (600 m). The several prospects drilled indicate nearly 18,000 ft (5,400 m) of Tertiary and Cretaceous sediments, with several thousand feet being mature and hydrocarbon generative. Drill-stem tests recovered oil and gas in one wildcat, and two others had oil and gas shows. End_Page 520------------------------------ By late 1978 the first-phase, 7-well exploratory program was completed. Two of the six basins had been tested. Individual wildcat costs using an anchored semisubmersible rig are in the $10 million to $20 million range. Despite adverse factors of extreme weather conditions, deep water, remoteness, and high drilling costs, more exploratory drilling will be necessary for final evaluation. The Sea Hunt Group is presently considering its second-stage drilling program for the area. End_of_Article - Last_Page 521------------

Potassium-argon ages of granites and metasediments from the Bounty Islands area, southwest Pacific Ocean

Abstract Potassium-argon dating of granites and a biotite-hornfels from the vicinity of the Bounty Islands indicates emplacement in Early Jurassic times, in the interval between the Tuhuan (Devonian — Carboniferous) and Rangi tata (Late Jurassic — Early Cretaceous) orogenies. Slight recrystallisation of a typical Bounty Platform argillite is dated as Early Triassic, which is much younger than the metamorphic ages (300–450 m.y.) that characterise the Lower Palaeozoic Greenland and Waiuta groups of the South Island, New Zealand. The age of recrystallisation of the Bounty Platform greywacke facies metasediments would thus seem to favour correlation with Permian to Lower Triassic sediments of the South Island, despite petrographic similarities to the Greenland and Waiuta rocks.

Potassium-argon ages of schists from Chatham Island, New Zealand Plateau, Southwest Pacific

Abstract The pre-Cretaceous basement rocks of Chatham Island consist of approximately 4750 m of interbedded felsic volcanic greywackes, black shales, terrigenous greywackes, and minor intermediate tuffs and cherts metamorphosed to the pumpellyite-actinolite facies. In part they resemble semi-schists and schists of textural zones I–III of the Otago belt, South Island, and have undergone three phases of folding synchronous with metamorphism. K-Ar ages for 11 total rock samples and ages for 10 mica samples of the Chatham Schist fall in the range 155–193 m.y., mostly between 157 and 162 m.y., and provide a minimum mid-jurassic age for the metamorphism associated with the jurassic-Cretaceous Rangitata Orogeny in the Chatham Islands. This is significantly older than the Lower Cretaceous estimate suggested by correlations with the Otago Schists of the South Island, N.Z., and implies either that rocks formed in an early Rangitata metamorphism (mid-jurassic) in the Chatham Islands were unaffected by later metamorphic events (Lower Cretaceous) occurring in the South Island, or that the post-orogenic cooling histories are different for the two areas. The ages for the Chatham Schist cannot be correlated with those obtained from other Rangitata metamorphic or igneous rocks from the Subantarctic islands of the Campbell Plateau, the South Island, New Zealand, and western Marie Byrd Land, Antarctica, which consistently yield Cretaceous ages (80–145 m.y.). An exception is the Bounty Islands granite (189 m.y.) which appears to predate the Rangitata metamorphism. However, dates in the age range 160–180 m.y. have been obtained from some intrusive rocks in the eastern part of West Antarctica.

Autochthonous rocks of the bounty islands region, south-west Pacific ocean

Abstract The Bounty Islands lie in the south-west Pacific, about 850 km east of southernmost New Zealand, and close to the eastern margin of the submerged quasicontinental crustal segment known as the Campbell Plateau. The islands themselves consist of coarse granodiorite, but autochthonous rocks dredged from the adjacent sea floor include quartz-feldspar porphyries, dioritic intrusives, and sedimentary rocks of greywacke facies. The granodiorites have been radiometrically dated as early Jurassic; the acidic and intermediate intrusives are presumably either syngenetic or younger. The greywackes are petrographically comparable with rocks of late Precambrian (?)-early Paleozoic age on the New Zealand mainland. The occurrence of a very similar assemblage of igneous and sedimentary rocks in Marie Byrd Land favours the supposed original proximity of Campbell Plateau and westernmost West Antarctica.

Arthropoda of the subantarctic islands of New Zealand

Ischyroplectron isolatum (Hutton) is redescribed from the Bounty Islands, south‐east of New Zealand. The relationships of the subantarctic Orthoptera are discussed. A key is given to the four genera of Rhaphidophoridae.

Age and Composition of a Bounty Islands Granite and Age of a Seychelles Islands Granite

Concordant ages of 189 m.y. were obtained on biotite from a Bounty Islands granite. ages of 638 m.y. and 681 m.y., respectively, were determined on a microcline and a whole rock sample of granite from Mahé Island in the Seychelles Archipelago.

XXXIX.—Description of a new Coleopterous Insect from Bounty Island

(1904). XXXIX.—Description of a new Coleopterous Insect from Bounty Island. Annals and Magazine of Natural History: Vol. 14, No. 82, pp. 273-274.

VI.—On a new genus of spiders from bounty island, with remarks on a species from New Zealand

VI.—<i>On a new genus of spiders from bounty island, with remarks on a species from New Zealand</i>