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- A subduction zone is a region of the earth's crust where one tectonic plate moves under another tectonic plate; oceanic crust gets recycled back into the mantle and continental crust gets created by the formation of arc magmas. Arc magmas account for more than 20% of terrestrially produced magmas and are produced by the dehydration of minerals within the subducting slab as it descends into the mantle and are accreted onto the base of the overriding continental plate. Subduction zones host a unique variety of rock types created by the high-pressure, low-temperature conditions a subducting slab encounters during its descent. The metamorphic conditions the slab passes through in this process creates and destroys water bearing (hydrous) mineral phases, releasing water into the mantle. This water lowers the melting point of mantle rock, initiating melting. Understanding the timing and conditions in which these dehydration reactions occur, is key to interpreting mantle melting, volcanic arc magmatism, and the formation of continental crust. A metamorphic facies is characterized by a stable mineral assemblage specific to a pressure-temperature range and specific starting material. Subduction zone metamorphism is characterized by a low temperature, high-ultrahigh pressure metamorphic path through the zeolite, prehnite-pumpellyite, blueschist, and eclogite facies stability zones of subducted oceanic crust. Zeolite and prehnite-pumpellyite facies assemblages may or may not be present, thus the onset of metamorphism may only be marked by blueschist facies conditions. Subducting slabs are composed of basaltic crust topped with pelagic sediments; however, the pelagic sediments may be accreted onto the forearc-hanging wall and not subducted. Most metamorphic phase transitions that occur within the subducting slab are prompted by the dehydration of hydrous mineral phases. The breakdown of hydrous mineral phases typically occurs at depths greater than 10 km. Each of these metamorphic facies is marked by the presence of a specific stable mineral assemblage, recording the metamorphic conditions undergone by the subducting slab. Transitions between facies cause hydrous minerals to dehydrate at certain pressure-temperature conditions and can therefore be tracked to melting events in the mantle beneath a volcanic arc. (en)
- 俯衝帶變質（英語：subduction zone metamorphisim）是指在岩石圈向下俯衝過程中，所經歷的低溫，高到超高壓變質環境，形成的一系列的變質岩相的礦物組合。由淺到深，變質岩相是沸石相（英語：zeolite facoies）、葡萄石-绿纤石相、藍片岩相和榴輝岩相（英語：eclogite facies） .俯衝板塊由玄武質地殼和上覆遠海沉積物組成, 然而，遠海沉積物多半被增生到弧前地區而不俯衝到深部。在俯衝中，板塊的變質多半是由含水礦物脫水引起的。含水礦物的分解通常在 10 公里的深度開始,將水釋放到地幔中。從而降低了地幔岩石的熔點，引發了部分熔融。 這些變質岩相中，每一個都有指標礦物組合，代表其經歷的變質環境。 了解這些脫水反應發生的時間和條件，是解釋地幔熔融、火山弧岩漿作用和大陸地殼形成的關鍵。 (zh)
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- 俯衝帶變質（英語：subduction zone metamorphisim）是指在岩石圈向下俯衝過程中，所經歷的低溫，高到超高壓變質環境，形成的一系列的變質岩相的礦物組合。由淺到深，變質岩相是沸石相（英語：zeolite facoies）、葡萄石-绿纤石相、藍片岩相和榴輝岩相（英語：eclogite facies） .俯衝板塊由玄武質地殼和上覆遠海沉積物組成, 然而，遠海沉積物多半被增生到弧前地區而不俯衝到深部。在俯衝中，板塊的變質多半是由含水礦物脫水引起的。含水礦物的分解通常在 10 公里的深度開始,將水釋放到地幔中。從而降低了地幔岩石的熔點，引發了部分熔融。 這些變質岩相中，每一個都有指標礦物組合，代表其經歷的變質環境。 了解這些脫水反應發生的時間和條件，是解釋地幔熔融、火山弧岩漿作用和大陸地殼形成的關鍵。 (zh)
- A subduction zone is a region of the earth's crust where one tectonic plate moves under another tectonic plate; oceanic crust gets recycled back into the mantle and continental crust gets created by the formation of arc magmas. Arc magmas account for more than 20% of terrestrially produced magmas and are produced by the dehydration of minerals within the subducting slab as it descends into the mantle and are accreted onto the base of the overriding continental plate. Subduction zones host a unique variety of rock types created by the high-pressure, low-temperature conditions a subducting slab encounters during its descent. The metamorphic conditions the slab passes through in this process creates and destroys water bearing (hydrous) mineral phases, releasing water into the mantle. This wat (en)
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- Subduction zone metamorphism (en)
- 俯衝帶變質 (zh)
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