The Tula A2-subtype granite pluton is located between the Altun fault and its branching fault. According to the geological, geochemical, REE and trace elements characteristics, it belongs to the A2 (PA) subtype gran...The Tula A2-subtype granite pluton is located between the Altun fault and its branching fault. According to the geological, geochemical, REE and trace elements characteristics, it belongs to the A2 (PA) subtype granite. The SHRIMP U-Pb zircon dating gives a result of 385.2±8.1 Ma, which is located between the Middle and Late Devonian in the international stratigraphic chart, and can be regarded as the crystallization age of the Tula granite. The study indicates that the Tula area was in a local extensional environment in the end of the Middle Devonian, and that environment was probably related to the synchronized strike-slip activity of the Altun fault.展开更多
The Bashikaogong-Shimierbulake granitoid complex is about 30 km long and 2―6 km wide, with an area of 140 km2, located at the north margin of the Bashikaogong Basin in the north Altun terrain. It intruded into schist...The Bashikaogong-Shimierbulake granitoid complex is about 30 km long and 2―6 km wide, with an area of 140 km2, located at the north margin of the Bashikaogong Basin in the north Altun terrain. It intruded into schist, metapelite and metatuff of Precambrian ages. This granitoid complex consists of darkish quartz diorite, grey granite, pink granite and pegmatite. Geochemically, the quartz diorite has I-type granite affinity and belongs to Calc-alkaline sereies, and the other gran- ites have S-type affinity and to high-K calc-alkaline series. Zircon SHRIMP U-Pb dating shows that the quartz diorite has a bigger age than those of other granites, which is 481.6±5.6 Ma for quartz diorite, 437.0±3.0 Ma―433.1±3.4 Ma for grey granite and 443±11 Ma―434.6±1.6 Ma for pink granite, re- spectively. Combined with regional geology, we think that the quartz diorite formed in tectonic envi- ronment related to oceanic crust subduction and the granites in post-collision.展开更多
文摘The Tula A2-subtype granite pluton is located between the Altun fault and its branching fault. According to the geological, geochemical, REE and trace elements characteristics, it belongs to the A2 (PA) subtype granite. The SHRIMP U-Pb zircon dating gives a result of 385.2±8.1 Ma, which is located between the Middle and Late Devonian in the international stratigraphic chart, and can be regarded as the crystallization age of the Tula granite. The study indicates that the Tula area was in a local extensional environment in the end of the Middle Devonian, and that environment was probably related to the synchronized strike-slip activity of the Altun fault.
基金This work was supported by the National Natural Science Foundation of China(Grant No.40472034)China Geological Survey Projects(Grant Nos.1212010611803 and 200313000058)+1 种基金the Chinese National Key Project for Basic Research(Grant No.2003CB716500)the National"973"Project(Grant No.G1988040800).
文摘The Bashikaogong-Shimierbulake granitoid complex is about 30 km long and 2―6 km wide, with an area of 140 km2, located at the north margin of the Bashikaogong Basin in the north Altun terrain. It intruded into schist, metapelite and metatuff of Precambrian ages. This granitoid complex consists of darkish quartz diorite, grey granite, pink granite and pegmatite. Geochemically, the quartz diorite has I-type granite affinity and belongs to Calc-alkaline sereies, and the other gran- ites have S-type affinity and to high-K calc-alkaline series. Zircon SHRIMP U-Pb dating shows that the quartz diorite has a bigger age than those of other granites, which is 481.6±5.6 Ma for quartz diorite, 437.0±3.0 Ma―433.1±3.4 Ma for grey granite and 443±11 Ma―434.6±1.6 Ma for pink granite, re- spectively. Combined with regional geology, we think that the quartz diorite formed in tectonic envi- ronment related to oceanic crust subduction and the granites in post-collision.