title: Discovery of halloysite books in altered silicic Quaternary tephras, northern New Zealand

authors: Cunningham, Michael J.

subjects: Halloysite

abstract: Hydrated halloysite was discovered in books, a morphology previously associated exclusively with kaolinite. From ~1.5 μm to ~1500 μm in length, the books showed significantly greater mean Fe contents (Fe2O3 = 5.2 wt%) than tubes (Fe2O3 = 3.2 wt%), and expanded rapidly with formamide. They occurred, along with halloysite tubes, spheroids, and plates, in highly porous yet poorly-permeable, silt-dominated, Si-rich, pumiceous rhyolitic tephra deposits aged ~0.93 Ma (Te Puna tephra) and ~0.27 Ma (Te Ranga tephra) at three sites ~10-20 m stratigraphically below the modern land-surface in the Tauranga area, eastern North Island, New Zealand. The book-bearing tephras were at or near saturation, but have experienced intermittent partial drying, favouring the proposed changes: solubilized volcanic glass + plagioclase -> halloysite spheroids -> halloysite tubes -> halloysite plates -> halloysite books. Unlike parallel studies elsewhere involving both halloysite and kaolinite, kaolinite has not formed in Tauranga presumably because the low permeability ensures the sites largely remain locally wet so that the halloysite books are metastable. An implication of the discovery is that some halloysite books in similar settings may have been misidentified previously as kaolinite.

text: Discovery of halloysite books in altered silicic Quaternary tephras, northern New Zealand Hydrated halloysite was discovered in books, a morphology previously associated exclusively with kaolinite. From ~1.5 μm to ~1500 μm in length, the books showed significantly greater mean Fe contents (Fe2O3 = 5.2 wt%) than tubes (Fe2O3 = 3.2 wt%), and expanded rapidly with formamide. They occurred, along with halloysite tubes, spheroids, and plates, in highly porous yet poorly-permeable, silt-dominated, Si-rich, pumiceous rhyolitic tephra deposits aged ~0.93 Ma (Te Puna tephra) and ~0.27 Ma (Te Ranga tephra) at three sites ~10-20 m stratigraphically below the modern land-surface in the Tauranga area, eastern North Island, New Zealand. The book-bearing tephras were at or near saturation, but have experienced intermittent partial drying, favouring the proposed changes: solubilized volcanic glass + plagioclase -> halloysite spheroids -> halloysite tubes -> halloysite plates -> halloysite books. Unlike parallel studies elsewhere involving both halloysite and kaolinite, kaolinite has not formed in Tauranga presumably because the low permeability ensures the sites largely remain locally wet so that the halloysite books are metastable. An implication of the discovery is that some halloysite books in similar settings may have been misidentified previously as kaolinite.

year: 2016-10-11

title: New foundations for Z

authors: Henson, Martin C.

subjects: computer science

abstract: We provide a constructive and intensional interpretation for the specification language Z in a theory of operations and kinds T. The motivation is to facilitate the development of an integrated approach to program construction. We illustrate the new foundations for Z with examples.

text: New foundations for Z We provide a constructive and intensional interpretation for the specification language Z in a theory of operations and kinds T. The motivation is to facilitate the development of an integrated approach to program construction. We illustrate the new foundations for Z with examples.

year: 1998-03

title: The Daldy Mcwilliams ‘Outrage’ of 1879

authors: Hart, Philip

abstract: In the later 1870s, conflicts developed near Paeroa between a small hapu, Ngati Hako, and other hapu over land sales and surveys. In 1879, after some members of Ngati Koi offered to sell the Pukehanga Block, at Rotokohu, between Paeroa and Te Aroha, to the Crown, surveyors were sent to determine the boundaries despite threats of violence from Ngati Hako. These threats became a reality with shots being fired, wounding a surveyor’s assistant, ‘Daldy’ McWilliams, who survived by playing dead. Despite Pakeha fury about a ‘weak’ response, officials reacted cautiously, fearing to provoke a wider conflict. 
Instead of trying to arrest the two men accused of the attempted murder, which would have been difficult, because Ngati Hako claimed their action was justified the Native Minister encouraged senior Hauraki rangatira to convene a rununga to examine their claim. Ngati Hako said that the block of land was theirs, and as previously other land had been surveyed without their permission they had taken this action. The government was criticized for paying advances on a block that had not been through the land court, and the rununga determined that although Ngati Hako had acted wrongfully, their action could be justified. When Ngati Hako refused to hand over the two accused to the authorities, the rununga claimed not to have the power to hand them over; Ngati Hako then constructed two pa to defend themselves.
Such actions provoked much frustration and criticisms of the government amongst Pakeha, but officials who investigated Ngati Hako’s complaints agreed that they had indeed lost land unjustly. Once the owners of a large domain, they had lost their land to the invading Marutuahu, whose slaves they became. When the two accused were arrested in 1882 one was found not guilty and the other was amnestied after eight months in prison because it was believed that, as rangatira, they probably had not fired the shots but had taken the responsibility for the actions of their hapu. As for McWilliams, he received what he considered inadequate compensation.
This ‘outrage’ was the first and only time in Hauraki that a Maori had shot a Pakeha, and the government’s cautious but firm response meant that the ‘peace of Hauraki’, although disturbed for a while, was maintained.

text: The Daldy Mcwilliams ‘Outrage’ of 1879 In the later 1870s, conflicts developed near Paeroa between a small hapu, Ngati Hako, and other hapu over land sales and surveys. In 1879, after some members of Ngati Koi offered to sell the Pukehanga Block, at Rotokohu, between Paeroa and Te Aroha, to the Crown, surveyors were sent to determine the boundaries despite threats of violence from Ngati Hako. These threats became a reality with shots being fired, wounding a surveyor’s assistant, ‘Daldy’ McWilliams, who survived by playing dead. Despite Pakeha fury about a ‘weak’ response, officials reacted cautiously, fearing to provoke a wider conflict. 
Instead of trying to arrest the two men accused of the attempted murder, which would have been difficult, because Ngati Hako claimed their action was justified the Native Minister encouraged senior Hauraki rangatira to convene a rununga to examine their claim. Ngati Hako said that the block of land was theirs, and as previously other land had been surveyed without their permission they had taken this action. The government was criticized for paying advances on a block that had not been through the land court, and the rununga determined that although Ngati Hako had acted wrongfully, their action could be justified. When Ngati Hako refused to hand over the two accused to the authorities, the rununga claimed not to have the power to hand them over; Ngati Hako then constructed two pa to defend themselves.
Such actions provoked much frustration and criticisms of the government amongst Pakeha, but officials who investigated Ngati Hako’s complaints agreed that they had indeed lost land unjustly. Once the owners of a large domain, they had lost their land to the invading Marutuahu, whose slaves they became. When the two accused were arrested in 1882 one was found not guilty and the other was amnestied after eight months in prison because it was believed that, as rangatira, they probably had not fired the shots but had taken the responsibility for the actions of their hapu. As for McWilliams, he received what he considered inadequate compensation.
This ‘outrage’ was the first and only time in Hauraki that a Maori had shot a Pakeha, and the government’s cautious but firm response meant that the ‘peace of Hauraki’, although disturbed for a while, was maintained.

year: 2016