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Manawahe Fault
The Manawahe Fault line is a seismically active area in the Bay of Plenty Region of the central North Island of New Zealand with the potential to be involved with other faults in an event. Geology North of Lake Rotomā, volcanic ignimbrite sheets from multiple eruptions of the Ōkataina Caldera extend towards the Whakatane Graben, with the volcanic region being separated from the tectonic Whakatane portion of the Taupō Rift by the Manawahe Fault. The fault continues to the east and coast in the Matata Fault line. The Manawahe Fault consists of a series of closely-spaced, mainly SSE-dipping fault traces, which are parallel to the North Rotoma Fault at the edge of the north eastern edge of the Rotoma Caldera. The traces are presumed to merge within of the surface. The Manawahe Fault ruptured immediately prior to the 5500 years ago Whakatane eruption of the Ōkataina Caldera and also ruptured several times, associated with the Rotoma Caldera eruptive sequence, and immediatel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manawahe
Manawahe is a rural area south of Matatā within the Whakatāne District and Bay of Plenty region of New Zealand's North Island. It is based in hills to the west of the Rangitaiki plain. Demographics Manawahe statistical area covers and had an estimated population of as of with a population density of people per km2. Manawahe had a population of 996 at the 2018 New Zealand census, an increase of 108 people (12.2%) since the 2013 census, and an increase of 174 people (21.2%) since the 2006 census. There were 381 households, comprising 498 males and 498 females, giving a sex ratio of 1.0 males per female. The median age was 48.9 years (compared with 37.4 years nationally), with 159 people (16.0%) aged under 15 years, 126 (12.7%) aged 15 to 29, 546 (54.8%) aged 30 to 64, and 165 (16.6%) aged 65 or older. Ethnicities were 84.9% European/Pākehā, 21.4% Māori, 1.2% Pacific peoples, 2.1% Asian, and 2.1% other ethnicities. People may identify with more than one ethnicity. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ignimbrite
Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surrounding atmosphere. New Zealand geologist Patrick Marshall (1869–1950) coined the term ''ignimbrite'' from the Latin ''igni-'' [fire] and ''imbri-'' [rain]. Ignimbrites are made of a very poorly sorted mixture of volcanic ash (or tuff when Lithification, lithified) and pumice lapilli, commonly with scattered lithic fragments. The ash is composed of glass shards and crystal fragments. Ignimbrites may be loose and unconsolidated, or lithified (solidified) rock called lapilli tuff. Near the volcanic source, ignimbrites often contain thick accumulations of lithic blocks, and distally, many show meter-thick accumulations of rounded cobbles of pumice. Ignimbrites may be white, grey, pink, beige, brown, or black depending on their composition and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic Faults Of New Zealand
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes (or generally, quakes) and the generation and propagation of elastic waves through planetary bodies. It also includes studies of the environmental effects of earthquakes such as tsunamis; other seismic sources such as volcanoes, plate tectonics, glaciers, rivers, oceanic microseisms, and the atmosphere; and artificial processes such as explosions. Paleoseismology is a related field that uses geology to infer information regarding past earthquakes. A recording of Earth's motion as a function of time, created by a seismograph is called a seismogram. A seismologist is a scientist who works in basic or applied seismology. History Scholarly interest in earthquakes can be traced back to antiquity. Early speculations on the natural causes of earthquakes were included in the writings of Thales of Miletus (), Anax ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matata Fault
The Matata Fault zone is a seismically active area in the Bay of Plenty Region of the central North Island of New Zealand with potential to rupture as part of an event. Geology The Matata Fault zone is the northwestern wall fault of the Whakatāne Graben and extends from the coast near Matatā to where the boundary of the modern Taupō Rift changes direction to a mainly SSE-dipping fault trace of the Manawahe Fault. At this southern end of the fault there is an area of Manawahe dacite that has been dated to 425,000 ± 27,000 years ago. There has been considerable uplift of Castlecliffian (mid Quaternary) marine sediments at a rate of /year to more than above sea level. An earthquake swam that commenced in 2005 at the northern end of the Matata Fault zone progressed off shore and lasted until 2009. At the coast there was an area of transition of a few miles with lower current seismic activity to defined off shore faults. These earthquakes were also associated with about of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ōkataina Caldera
Ōkataina Caldera (Ōkataina Volcanic Centre, also spelled Okataina) is a volcano, volcanic caldera and its associated volcanoes located in Taupō Volcanic Zone of New Zealand's North Island. It has several actual or postulated sub calderas. The Ōkataina Caldera is just east of the smaller separate Rotorua Caldera and southwest of the much smaller Rotomā Caldera, Rotomā Embayment which is usually regarded as an associated volcano. It shows high rates of explosive rhyolite, rhyolitic volcanism although its last eruption was basaltic. The postulated Haroharo Caldera contained within it has sometimes been described in almost interchangeable terms with the Ōkataina Caldera or volcanic complex or centre and by other authors as a separate complex defined by gravitational and magnetic features..Possibly started from with the author presuming that certain ignimbrites came from this source. The term Haroharo Caldera was increasingly used in academic papers in the 1970's and 1980's but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Rotomā
Lake Rotomā (also spelled Rotoma) is the fourth largest lake of the 11 lakes in the Rotorua Lakes district in the Bay of Plenty Region of New Zealand's North Island. Lake Rotomā is the easternmost in the chain of three lakes to the northeast of Lake Rotorua The other two are Lake Rotoiti and Lake Rotoehu. Rotomā is located halfway between the city of Rotorua and town of Whakatāne. Lake Rotomā has a high water quality with visibility up to around 13 metres deep. The lake has a maximum depth of 83 metres in the northern part and 73.5 metres in the southern part. Geography Lake Rotomā was formed within the Rotomā Caldera when lava flows from a large crater explosion blocked its outlet 9,500 years ago. The hills fringing the south and east of the lake are made up of rhyolite from eruptions from its own caldera, the Haroharo and Tarawera vent alignments, all in the Ōkataina Volcanic Centre. Inflow is from rainfall, three small streams and several springs around the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taupō Rift
The Taupō Rift is the seismically active rift valley containing the Taupō Volcanic Zone, central North Island of New Zealand. Geology The Taupō Rift (Taupo Rift) is a intra-arc continental rift resulting from an oblique convergence in the Hikurangi subduction zone. The present young, modern Taupō Rift is defined by events between 25,000 and 350,000 years and the old Taupō Rift system, which can be defined by a gravity anomaly, is now located more to the north being created between 350,000 and 2 million years and is about wide. Consensus does not yet exist with regard to the cause of the Taupō Rift's extension or the exceptional volcanic productivity of the associated Taupō Volcanic Zone. Its geology and landforms are of worldwide interest, and it contains multiple significant faults and volcanoes, with some of the volcanoes having potential for worldwide impact. Volcanic context The recent volcanism of the Taupō Volcanic Zone has been divided into three segments, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taupō Volcanic Zone
The Taupō Volcanic Zone (TVZ) is a volcano, volcanic area in the North Island of New Zealand. It has been active for at least the past two million years and is still highly active. Mount Ruapehu marks its south-western end and the zone runs north-eastward through the Taupō and Rotorua areas and offshore into the Bay of Plenty. It is part of a larger Central Volcanic Region that extends to the Coromandel Peninsula and has been active for four million years. The zone is contained within the Tectonics, tectonic intra-arc continental Taupō Rift and this rift volcanic zone is widening unevenly east–west, with the greatest rate of widening at the Bay of Plenty coast, the least at Mount Ruapehu and a rate of about per year at Taupō. The zone is named after Lake Taupō, the flooded caldera of the largest volcano in the zone, the Taupō Volcano and contains a large central North Island Volcanic Plateau, volcanic plateau as well as other landforms. Activity There are numerous vol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holocene
The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene is an interglacial period within the ongoing Ice age, glacial cycles of the Quaternary, and is equivalent to Marine isotope stages, Marine Isotope Stage 1. The Holocene correlates with the last maximum axial tilt towards the Sun of the Earth#Axial tilt and seasons, Earth's obliquity. The Holocene corresponds with the rapid proliferation, growth, and impacts of the human species worldwide, including Recorded history, all of its written history, technological revolutions, development of major civilizations, and overall significant transition towards urban culture, urban living in the present. The human impact on modern-era Earth and its ecosystems may be considered of global significance for th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
