title: Ages on weathered Plio-Pleistocene tephra sequences, western North Island, New Zealand

authors: Lowe, David J.

subjects: tephra

abstract: Using the zircon fission-track method, we have obtained five ages on members of two strongly-weathered silicic, Pliocene-Pleistocene tephra sequences, the Kauroa and Hamilton Ash formations, in western North Island, New Zealand. These are the first numerical ages to be obtained directly on these deposits. Of the Kauroa Ash sequence, member K1 (basal unit) was dated at 2.24 ± 0.29 Ma, confirming a previous age of c. 2.25 Ma obtained (via tephrochronology)from K/Ar ages on associated basalt lava. Members K2 and K3 gave indistinguishable ages between 1.68 ± 0.12 and 1.43 ± 0.17 Ma. Member K12, a correlative of Oparau Tephra and probably also Ongatiti Ignimbrite, was dated at 1.28 ± 0.11 Ma, consistent with an age of 1.23 ± 0.02 Ma obtained by various methods on Ongatiti Ignimbrite. Palaeomagnetic measurements indicated that members K13 to K15 (top unit, Waiterimu Ash) are aged between c. 1.2 Ma and 0.78 Ma. Possible sources of the Kauroa Ash Formation include younger volcanic centres in the southern Coromandel Volcanic Zone or older volcanic centres in the Taupo Volcanic Zone, or both. Of the Hamilton Ash sequence, the basal member Ohinewai Ash (HI) was dated at 0.38 ± 0.04 Ma. This age matches those obtained by various methods on Rangitawa Tephra of 0.34-0.35 Ma, supporting correlation with this Whakamaru-caldera derived deposit. The origin of the other Hamilton Ash beds is unknown but various younger volcanic centres in the Taupo Volcanic Zone are possible sources. The topmost member, Tikotiko Ash (H6-H7), is estimated to be aged between c. 0.18 and 0.08 Ma. Various silicic pyroclastic deposits documented in North Island and in marine cores may be co-eval with members of the Kauroa Ash and Hamilton Ash sequences on the basis of their age.

text: Ages on weathered Plio-Pleistocene tephra sequences, western North Island, New Zealand Using the zircon fission-track method, we have obtained five ages on members of two strongly-weathered silicic, Pliocene-Pleistocene tephra sequences, the Kauroa and Hamilton Ash formations, in western North Island, New Zealand. These are the first numerical ages to be obtained directly on these deposits. Of the Kauroa Ash sequence, member K1 (basal unit) was dated at 2.24 ± 0.29 Ma, confirming a previous age of c. 2.25 Ma obtained (via tephrochronology)from K/Ar ages on associated basalt lava. Members K2 and K3 gave indistinguishable ages between 1.68 ± 0.12 and 1.43 ± 0.17 Ma. Member K12, a correlative of Oparau Tephra and probably also Ongatiti Ignimbrite, was dated at 1.28 ± 0.11 Ma, consistent with an age of 1.23 ± 0.02 Ma obtained by various methods on Ongatiti Ignimbrite. Palaeomagnetic measurements indicated that members K13 to K15 (top unit, Waiterimu Ash) are aged between c. 1.2 Ma and 0.78 Ma. Possible sources of the Kauroa Ash Formation include younger volcanic centres in the southern Coromandel Volcanic Zone or older volcanic centres in the Taupo Volcanic Zone, or both. Of the Hamilton Ash sequence, the basal member Ohinewai Ash (HI) was dated at 0.38 ± 0.04 Ma. This age matches those obtained by various methods on Rangitawa Tephra of 0.34-0.35 Ma, supporting correlation with this Whakamaru-caldera derived deposit. The origin of the other Hamilton Ash beds is unknown but various younger volcanic centres in the Taupo Volcanic Zone are possible sources. The topmost member, Tikotiko Ash (H6-H7), is estimated to be aged between c. 0.18 and 0.08 Ma. Various silicic pyroclastic deposits documented in North Island and in marine cores may be co-eval with members of the Kauroa Ash and Hamilton Ash sequences on the basis of their age.

year: 2001

title: Non-attendance to attributes in environmental choice analysis: a latent class specification

authors: Campbell, Danny

subjects: attribute non-attendance

abstract: There is a growing literature on the design and use of stated choice experiments. Analysts have developed sophisticated ways of analysing such data, using a form of discrete choice model to identify the marginal (dis)utility associated with observed attributes linked to an alternative, as well as accounting for preference and scale heterogeneity. There is also a growing literature studying the attribute processing rules that respondents use as a way of simplifying the task of choosing. Using the latent class framework, we define classes based on rules that recognise the non-attendance to one or more attributes. These processing rules are postulated to be used in real markets as a form of cognitive rationalisation. The empirical study involves a choice amongst rural environmental landscape improvements in the Republic of Ireland. We estimate models and calculate a marginal willingness to pay (WTP) for four landscape improvements, and contrast it with the results from a model specification in which all attributes are assumed to be attended to with parameter preservation. We find that the marginal WTP is, on average, significantly higher when full attribute preservation specification is adopted, raising questions about the appropriateness of current practice that assume a fully compensatory attribute choice rule.

text: Non-attendance to attributes in environmental choice analysis: a latent class specification There is a growing literature on the design and use of stated choice experiments. Analysts have developed sophisticated ways of analysing such data, using a form of discrete choice model to identify the marginal (dis)utility associated with observed attributes linked to an alternative, as well as accounting for preference and scale heterogeneity. There is also a growing literature studying the attribute processing rules that respondents use as a way of simplifying the task of choosing. Using the latent class framework, we define classes based on rules that recognise the non-attendance to one or more attributes. These processing rules are postulated to be used in real markets as a form of cognitive rationalisation. The empirical study involves a choice amongst rural environmental landscape improvements in the Republic of Ireland. We estimate models and calculate a marginal willingness to pay (WTP) for four landscape improvements, and contrast it with the results from a model specification in which all attributes are assumed to be attended to with parameter preservation. We find that the marginal WTP is, on average, significantly higher when full attribute preservation specification is adopted, raising questions about the appropriateness of current practice that assume a fully compensatory attribute choice rule.

year: 2011

title: ‘Revolting murder at Te Aroha’ in 1881

authors: Hart, Philip

abstract: The brutal murder of Hamiona Haira, who had been mining with his two brothers and his father-in-law, shocked the new settlement. Being a member of Ngati Koi and Ngati Hako, these hapu threatened utu on the Pakeha responsible, causing both Maori and Pakeha miners to abandon their claims at Tui. Suspicion immediately fell on John Procoffy, a Finn, and evidence was quickly collected, officials being anxious to obtain a speedy conviction to avoid an innocent Pakeha being killed in revenge. Rangatira agreed to let the courts deal with the case, although some Pakeha criticized the government for being too anxious to appease Maori.
After a coroner’s inquest, which included Maori as members of the jury, returned a verdict of murder by ‘person or persons unknown’, Procoffy faced two trials. As the prosecution was handicapped by the limitations of contemporary forensic skills, its case was largely circumstantial. Although the police were certain they had their murderer, others were not convinced, and there was a reluctance to convict because of the death penalty. The final outcome was a verdict of not guilty, which, as was pointed out, should have been ‘not proven’. 
Procoffy fled the country. His acquittal was accepted by Maori leaders, and calm returned to Te Aroha.

text: ‘Revolting murder at Te Aroha’ in 1881 The brutal murder of Hamiona Haira, who had been mining with his two brothers and his father-in-law, shocked the new settlement. Being a member of Ngati Koi and Ngati Hako, these hapu threatened utu on the Pakeha responsible, causing both Maori and Pakeha miners to abandon their claims at Tui. Suspicion immediately fell on John Procoffy, a Finn, and evidence was quickly collected, officials being anxious to obtain a speedy conviction to avoid an innocent Pakeha being killed in revenge. Rangatira agreed to let the courts deal with the case, although some Pakeha criticized the government for being too anxious to appease Maori.
After a coroner’s inquest, which included Maori as members of the jury, returned a verdict of murder by ‘person or persons unknown’, Procoffy faced two trials. As the prosecution was handicapped by the limitations of contemporary forensic skills, its case was largely circumstantial. Although the police were certain they had their murderer, others were not convinced, and there was a reluctance to convict because of the death penalty. The final outcome was a verdict of not guilty, which, as was pointed out, should have been ‘not proven’. 
Procoffy fled the country. His acquittal was accepted by Maori leaders, and calm returned to Te Aroha.

year: 2016