title: Late Miocene-Early Pliocene Matemateaonga Formation in eastern Taranaki Peninsula: A new 1:50,000 geological map and stratigraphic framework

authors: Vonk, Adam J.

subjects: Taranaki Basin

abstract: In recent years the Matemateaonga Formation has become an additional exploration play in Taranaki Basin. Exploration interest has been stimulated by the success of Swift Energy Company in the Rimu/Kauri prospect (38719), located near south Taranaki Coast. At this location, sandstone lithofacies, commonly termed “Manutahi Sandstone” in the lower parts of the Matemateaonga Formation have been intersected by the Kauri-A2 and Kauri-A3 wells at depths of ~1100-1200 m and are yielding commercial quantities of oil.
As part of a FRST-funded sedimentary basins research programme, we have geologically mapped in detail Matemateaonga Formation within an 1800 km2 area of the eastern peninsula region (Fig. 1), incorporating license areas 38739, 38718, 38753, 38138, 38139, 38141, 38140, 38716, 38758, 38728 and 38760. Mapping at 1:50,000 scale has revealed an ~1100 m-thick succession of cyclothemic, unconformity bounded shelfal strata of Late Miocene-Early Pliocene (Late Kapitean to Early Opoitian) age (c.5.5-4.7 Ma). This succession formed as a result of the interplay between climatically-driven 6th-order (41 k.y.) eustatic sea-level changes, high rates of basin subsidence and a substantial southerly-derived sediment flux. Individual sequences or groups of sequences are the fundamental mapping entities. The mapping area sits astride the southward-plunging Whangamomona Anticline, which has deformed the Late Neogene succession, producing a regional dip on its western flank of 2 to 4 degrees to the southwest. Northeast-southwest trending normal faults are relatively common and offset Matemateaonga Formation strata with throws of 2-50 m.
This improved knowledge of Matemateaonga Formation stratigraphy enhances the understanding of the distribution and geometry of potential reservoir sandstone units and associated mudstone seal units in the region.

text: Late Miocene-Early Pliocene Matemateaonga Formation in eastern Taranaki Peninsula: A new 1:50,000 geological map and stratigraphic framework In recent years the Matemateaonga Formation has become an additional exploration play in Taranaki Basin. Exploration interest has been stimulated by the success of Swift Energy Company in the Rimu/Kauri prospect (38719), located near south Taranaki Coast. At this location, sandstone lithofacies, commonly termed “Manutahi Sandstone” in the lower parts of the Matemateaonga Formation have been intersected by the Kauri-A2 and Kauri-A3 wells at depths of ~1100-1200 m and are yielding commercial quantities of oil.
As part of a FRST-funded sedimentary basins research programme, we have geologically mapped in detail Matemateaonga Formation within an 1800 km2 area of the eastern peninsula region (Fig. 1), incorporating license areas 38739, 38718, 38753, 38138, 38139, 38141, 38140, 38716, 38758, 38728 and 38760. Mapping at 1:50,000 scale has revealed an ~1100 m-thick succession of cyclothemic, unconformity bounded shelfal strata of Late Miocene-Early Pliocene (Late Kapitean to Early Opoitian) age (c.5.5-4.7 Ma). This succession formed as a result of the interplay between climatically-driven 6th-order (41 k.y.) eustatic sea-level changes, high rates of basin subsidence and a substantial southerly-derived sediment flux. Individual sequences or groups of sequences are the fundamental mapping entities. The mapping area sits astride the southward-plunging Whangamomona Anticline, which has deformed the Late Neogene succession, producing a regional dip on its western flank of 2 to 4 degrees to the southwest. Northeast-southwest trending normal faults are relatively common and offset Matemateaonga Formation strata with throws of 2-50 m.
This improved knowledge of Matemateaonga Formation stratigraphy enhances the understanding of the distribution and geometry of potential reservoir sandstone units and associated mudstone seal units in the region.

year: 2004

title: Tephra studies in New Zealand: an historical review.

authors: Lowe, David J.

subjects: Tephrostratigraphy

abstract: The development of tephra studies in New Zealand may be divided into four main periods: Period 1, late 19th century to late 1920s; Period 2, late 1920s to early 1950s; Period 3, early 1950s to 1973; Period 4, 1973 to late 1980s. The important events and advances that characterise each of these periods, and their causes and influences, are described with reference to contemporary scientists and their publications. Period 1: determination by dendrochronology of first numerical age of a prehistorical eruptive (Burrell Lapilli); first isopach map (Tarawera Tephra). Period 2: first tephra mapping in central North Island (for soil survey). Period 3: first use of 14 C dating; establishment of late Quaternary tephrostratigraphic framework by 'hand over hand' mapping in central North Island and Taranaki; initial development of tephra 'fingerprinting' using laboratory methods; application of tephrochronology to many disciplines. Period 4: revision and refinement of proximal stratigraphy, particularly in central TVZ calderas and on Mayor Island; extension of tephra mapping to distal regions, on and offshore, and to older deposits; advances in tephra correlation and dating methods; new tephrochronological applications; revolutionary studies of pyroclastic deposits for determining nature and effects of eruptions (physical volcanology and petrology); renewed awareness of volcanic hazards associated with tephra eruptions. The advances relate to indigenous, external, and 'individualistic' factors. They generally parallelled overseas trends but in some topics preceded or lagged behind them. Tephra studies, or "tephrology", may be regarded as having "come of age" early in the 1980s, about 100 years after the first tephrostratigraphic studies in New Zealand.

text: Tephra studies in New Zealand: an historical review. The development of tephra studies in New Zealand may be divided into four main periods: Period 1, late 19th century to late 1920s; Period 2, late 1920s to early 1950s; Period 3, early 1950s to 1973; Period 4, 1973 to late 1980s. The important events and advances that characterise each of these periods, and their causes and influences, are described with reference to contemporary scientists and their publications. Period 1: determination by dendrochronology of first numerical age of a prehistorical eruptive (Burrell Lapilli); first isopach map (Tarawera Tephra). Period 2: first tephra mapping in central North Island (for soil survey). Period 3: first use of 14 C dating; establishment of late Quaternary tephrostratigraphic framework by 'hand over hand' mapping in central North Island and Taranaki; initial development of tephra 'fingerprinting' using laboratory methods; application of tephrochronology to many disciplines. Period 4: revision and refinement of proximal stratigraphy, particularly in central TVZ calderas and on Mayor Island; extension of tephra mapping to distal regions, on and offshore, and to older deposits; advances in tephra correlation and dating methods; new tephrochronological applications; revolutionary studies of pyroclastic deposits for determining nature and effects of eruptions (physical volcanology and petrology); renewed awareness of volcanic hazards associated with tephra eruptions. The advances relate to indigenous, external, and 'individualistic' factors. They generally parallelled overseas trends but in some topics preceded or lagged behind them. Tephra studies, or "tephrology", may be regarded as having "come of age" early in the 1980s, about 100 years after the first tephrostratigraphic studies in New Zealand.

year: 1990-03-01

title: Tūhoe on the move: Regional mobility

authors: Guerin, Pauline

abstract: Academic interest in geographic mobility of indigenous peoples has increased in recent years with a corresponding growth in the literature relating to Māori mobility more specifically. With this greater acknowledgement of Māori issues has also come an awareness of the need for iwi-specific research because of the diversity within and between Māori and iwi. The present research contributes to a larger project exploring Tūhoe regional mobility. In this paper, we analyse published data and unpublished census data from 2001 that relate specifically to Tūhoe regional mobility and the relationship between mobility and language. Region of residence in 1996 and 2001 were analysed in relation to age, sex, and broad language groups. Overall, this analysis found important and diverse relationships between age, sex, language, and region of residence in New Zealand among Māori who identify as Tūhoe. For example, patterns of mobility for different age groups and sex had some similarities with other research, such as a higher proportion of “stayers” in older age groups, but differences were also found, such as higher proportions of “movers” among females in some age groups. Interestingly, we found that language between “movers” and “stayers” differed depending on the region of residence. A greater proportion of “movers” were able to converse in Māori in Auckland and the Waikato, but a slightly greater proportion of “stayers” could converse in Māori in the Hawke’s Bay and Bay of Plenty. These results suggest that geographic mobility among Māori, and Tūhoe more specifically, are complex and should not be overly-simplified in more aggregate analyses.

text: Tūhoe on the move: Regional mobility Academic interest in geographic mobility of indigenous peoples has increased in recent years with a corresponding growth in the literature relating to Māori mobility more specifically. With this greater acknowledgement of Māori issues has also come an awareness of the need for iwi-specific research because of the diversity within and between Māori and iwi. The present research contributes to a larger project exploring Tūhoe regional mobility. In this paper, we analyse published data and unpublished census data from 2001 that relate specifically to Tūhoe regional mobility and the relationship between mobility and language. Region of residence in 1996 and 2001 were analysed in relation to age, sex, and broad language groups. Overall, this analysis found important and diverse relationships between age, sex, language, and region of residence in New Zealand among Māori who identify as Tūhoe. For example, patterns of mobility for different age groups and sex had some similarities with other research, such as a higher proportion of “stayers” in older age groups, but differences were also found, such as higher proportions of “movers” among females in some age groups. Interestingly, we found that language between “movers” and “stayers” differed depending on the region of residence. A greater proportion of “movers” were able to converse in Māori in Auckland and the Waikato, but a slightly greater proportion of “stayers” could converse in Māori in the Hawke’s Bay and Bay of Plenty. These results suggest that geographic mobility among Māori, and Tūhoe more specifically, are complex and should not be overly-simplified in more aggregate analyses.

year: 2006