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Mount Hachimantai
is the highest peak of a group of stratovolcanos distributed around the Hachimantai plateau in the Ōu Mountains in northern Honshū, Japan. This volcanic plateau is part of the Nasu Volcanic Zone and straddles the border between the Iwate Prefecture and Akita Prefecture. The volcano is listed as one of the 100 Famous Japanese Mountains, and forms part of the Towada-Hachimantai National Park. Etymology There are several legends concerning the origin of the name “Hachimantai”. In one legend, the late Nara period General Sakanoue no Tamuramaro pursued a group of Emishi warriors into the area, and was so impressed with the natural beauty of the region that he said it must be the abode of the ''kami'' Hachiman. In another legend, the area was named after Minamoto Yoshiie, a late Heian period warrior whose nickname was “Hachiman Tarō”. Geography Situation The Hachimantai plateau is located approximately south of Lake Towada and northeast of Lake Tazawa, within the border ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ōu Mountains
The are a mountain range in the Tōhoku region of Honshū, Japan. The range is the longest range in Japan and stretches south from the Natsudomari Peninsula of Aomori Prefecture to the Nasu volcanoes at the northern boundary of the Kantō region. Though long, the range is only about wide. The highest point in the range is Mount Iwate, . The range includes several widely known mountains: Hakkōda Mountains, Mount Iwate, Mount Zaō, Mount Azuma, Mount Yakeishi, and Mount Adatara. Naming These mountains previously formed the boundary between historical provinces of Mutsu (陸奥国) and Dewa (出羽国). The ''kanji'' for the name of the mountain range was created from one ''kanji'' of the two provinces, 奥 and 羽, respectively. Geology The Ōu Mountains began to form in the Pliocene. They sit over the middle of the inner arc of the Northeastern Japan Arc. This is the result of the Pacific Plate subducting under the Okhotsk Plate The Okhotsk Plate is a minor tect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Towada
is the largest crater lake in Honshū island, Japan. Located on the border between Aomori and Akita prefectures, it lies 400 meters (1,800 ft) above sea level and is 327 m (1,073 ft) deep, drained by the Oirase river. With a surface area of 61.1 km², Towada is Japan's 12th largest lake, its bright blue color is due to its great depth. The lake is roughly circular, with two peninsulas extending from its southern shore approximately one-third into the center of the lake. The lake is a popular tourist destination. Location Lake Towada is located approximately northeast of Tokyo, divided between the municipalities of Towada, Aomori and Kosaka, Akita. It forms part of the northern section of Towada-Hachimantai National Park Geology Lake Towada occupies the caldera of a stratovolcano still regarded as an active volcano. This volcano became active around 200,000 years ago, and through repeated eruptions and pyroclastic flows, especially 55,000 and 36,000 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek grc, label=none, πλεῖστος, pleīstos, most and grc, label=none, καινός, kainós (latinized as ), 'new'. At the end of the preceding Pliocene, the previously isolated North and South American continents were joined by the Isthmus of Panama, causing Great American Interchang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroclastic Rock
Pyroclastic rocks (derived from the el, πῦρ, links=no, meaning fire; and , meaning broken) are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroclasts. Pyroclastic rocks are a type of volcaniclastic deposit, which are deposits made predominantly of volcanic particles. 'Phreatic' pyroclastic deposits are a variety of pyroclastic rock that forms from volcanic steam explosions and they are entirely made of accidental clasts. 'Phreatomagmatic' pyroclastic deposits are formed from explosive interaction of magma with groundwater. Unconsolidated accumulations of pyroclasts are described as tephra. Tephra may become lithified to a pyroclastic rock by cementation or chemical reactions as the result of the passage of hot gases (fumarolic alteration) or groundwater (e.g. hydrothermal alteration and diagenesis) and burial, or, if it is emplaced at temperatures so hot that the soft glassy pyrocl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or ''granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) contain almost no dark minerals. Granite is nearly alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rock
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies (marine snow). Sedimentation may also occur as dissolved minerals precipitate from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoic
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ''zōḗ'' (), "life", meaning "ancient life" ). It is the longest of the Phanerozoic eras, lasting from , and is subdivided into six geologic periods (from oldest to youngest): # Cambrian # Ordovician # Silurian # Devonian # Carboniferous # Permian The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earth's history, known as the Cambrian explosion, in which most modern phyla first appeared. Arthropods, molluscs, fish, amphibians, reptiles, and synapsids all evolved during the Paleozoic. Life began in the ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tertiary
Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start of the Cenozoic Era, and extended to the beginning of the Quaternary glaciation at the end of the Pliocene Epoch. The time span covered by the Tertiary has no exact equivalent in the current geologic time system, but it is essentially the merged Paleogene and Neogene periods, which are informally called the Early Tertiary and the Late Tertiary, respectively. The Tertiary established the Antarctic as an icy island continent. Historical use of the term The term Tertiary was first used by Giovanni Arduino during the mid-18th century. He classified geologic time into primitive (or primary), secondary, and tertiary periods based on observations of geology in Northern Italy. Later a fourth period, the Quaternary, was applied. In the early d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Shield
A shield volcano is a type of volcano named for its low profile, resembling a warrior's shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano. Repeated eruptions result in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form. Shield volcanoes are found wherever fluid low-silica lava reaches the surface of a rocky planet. However, they are most characteristic of ocean island volcanism associated with hot spots or with continental rift volcanism. They include the largest volcanoes on earth, such as Tamu Massif and Mauna Loa. Giant shield volcanoes are found on other planets of the Solar System, including Olympus Mons on Mars and Sapas Mons on Venus. Etymology The term 'shield volcano' is taken from the German term ''Schildvulkan'', coined by the Austrian geologist Eduard Suess in 1888 and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Iwate
is a stratovolcano complex in the Ōu Mountains of western Iwate Prefecture, in the Tōhoku region of northern Honshū, Japan. With an elevation of , it is the highest in Iwate Prefecture. It is included as one of the 100 famous mountains in Japan, a book composed in 1964 by mountaineer and author Kyūya Fukada.Hyakumeizan, Hiking Japan! . Japan Gazetteer. Accessed June 27, 2008. The mountain is on the borders of the municipalities of Hachimantai, Takizawa, and , west of the prefectural capit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Akita-Komagatake
is an active stratovolcano located 10 km east of Tazawa Lake, near the border between Akita and Iwate prefectures on Honshu Island. The volcano last erupted from 18 September 1970 to 25 January 1971. It is the highest mountain in Akita Prefecture and the second highest in Towada-Hachimantai National Park is a national park comprising two separate areas of Aomori, Iwate, and Akita Prefectures, Japan. The Towada-Hakkōda area encompasses Lake Towada, Mount Hakkōda, and most of the Oirase River valley. The Hachimantai area includes Mount Hachim .... References External links * Akita-Komagatake- Japan Meteorological Agency * - Japan Meteorological Agency - Geological Survey of Japan Akita-Komagatake: Global Volcanism Program- Smithsonian Institution Volcanoes of Honshū Active volcanoes Mountains of Akita Prefecture Volcanoes of Akita Prefecture Stratovolcanoes of Japan Tourist attractions in Akita Prefecture Pleistocene stratovolcanoes Holocene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
