Separation system and sale and purchase of land are the reasons of land chronology.The sale and exchange of land are the ways to address land chronology.However,the traditional society can not solve this issue.After n...Separation system and sale and purchase of land are the reasons of land chronology.The sale and exchange of land are the ways to address land chronology.However,the traditional society can not solve this issue.After new China was founded,it was Failure to resolve the land chronology by political means.It is a correct direction to transfer land in accordance with the principle of law,voluntary and paid.展开更多
Geology setting and petrological features Qiangtang composite plate is located between Xijinwulan—Jinshajiang and Bangonghu—Nujiang suture zones, with the total area of several ten thousand square kilometers. The ex...Geology setting and petrological features Qiangtang composite plate is located between Xijinwulan—Jinshajiang and Bangonghu—Nujiang suture zones, with the total area of several ten thousand square kilometers. The exposed rocks are mainly Paleozoic, Mesozoic marine sedimentary rocks.. Around Zhabu—Shuanghu area, there exits a post late Triassic uplift, in which middle Devonian low\|intermediate degree metamorphic rocks with solid chronological evidence have been found. However, in central Qiangtang, debate is still there in several aspects, such as there is crystalline basement or not, basement features, and the pre\|Devonian evolution of Qiangtang plate, etc. (Cai Li et al.,1997)Duguer gneiss is the only proved gneiss in Qiangtang region upto now, which is exposed at Duguer mountain (peak, 6208m above sea level), Gaize county, and is confined by faults. An E—W oriented thrust fault zone is its south boundary, which is more than 200m wide and makes the gneiss overthrust on upper Carboniferous strata and Tertiary red beds southwardly. On the east and north sides of the gneiss are upper Carboniferous strata. The gneiss occurs as a triangle form with a long E—W trending bottom line (about 20km) and a height about 10km in S—N direction, which is the main part of Duguer Duguer mountain.Duguer gneiss consists of two rocks types, i.e. granitic gneiss (the dominant component) and amphibole\|plagioclase gneiss. The latter one occurs as a group of nearly E—W trending dikes with clear boundary, which are obviously late basic dikes that intruded into granite. Granitic gneiss is composed of porphyroclast granitic gneiss, banded granitic gneiss, gneissoid granite and granitic mylonite. Both granitic and amphibole\|plagioclase gneisses have been undergone same type and same degree metamorphism and deformation. The typical mineral assemblage of the former gneiss include quartz(30%), microcline(25%),plagioclase(30%), two mica (biotite +muscovite,13%) and the accessory minerals such as zircon, magnetite, and apatite etc. The main oxide contents of the granitic gneiss are (average of three samples) 73 53% SiO\-2, 12 9% Al\-2O\-3, 1 57% FeO, 0 52% MgO, 3 24%Na\-2O and 0 22% K\-2O. The REE distribution pattern shows typical features of granite, i.e. LREE enrichment, HREE depletion and rather strong negative Eu anomaly.展开更多
It bas been considered that large\|scale basic igneous activities are related to results of the break\|up of paleo\|continent. Basic magmatism could record the dynamics information for orogenic process. Thus, studying...It bas been considered that large\|scale basic igneous activities are related to results of the break\|up of paleo\|continent. Basic magmatism could record the dynamics information for orogenic process. Thus, studying it can help us to reconstruct the forming and evolution process of continental orogenic zone.The basic igneous zone in the central part of Qiangtang, Tibet, starts at the Sino\|Indian border in the west and ends at Shuanghu region in the east, being over 800km long and several to more than 100km wide. Based on published data, there are coeval basic magmatic activities with similar features in Sanjiang region, Western Yunnan and Thai\|Malaysian Peninsula. the basic dykes from Boyamalong to Qomu in central Qiangtang occur in swarms with E\|W trending and are more than one thousand in number. Single or composite igneous body is 1 to 7 km long and 0.3 to 3 km wide, being of the area of 0.3 to 20km\+2 . The total exposed area of the dykes is more than 400km\+2 . The country rocks of the intrusives are the upper Carboniferous Mushirbuka group, which consists of rift\|type deposits containing glaciomarine petromictic conglomerates.No basic dyke has been found in the strata since late Permian (Mokou Period)展开更多
文摘Separation system and sale and purchase of land are the reasons of land chronology.The sale and exchange of land are the ways to address land chronology.However,the traditional society can not solve this issue.After new China was founded,it was Failure to resolve the land chronology by political means.It is a correct direction to transfer land in accordance with the principle of law,voluntary and paid.
文摘Geology setting and petrological features Qiangtang composite plate is located between Xijinwulan—Jinshajiang and Bangonghu—Nujiang suture zones, with the total area of several ten thousand square kilometers. The exposed rocks are mainly Paleozoic, Mesozoic marine sedimentary rocks.. Around Zhabu—Shuanghu area, there exits a post late Triassic uplift, in which middle Devonian low\|intermediate degree metamorphic rocks with solid chronological evidence have been found. However, in central Qiangtang, debate is still there in several aspects, such as there is crystalline basement or not, basement features, and the pre\|Devonian evolution of Qiangtang plate, etc. (Cai Li et al.,1997)Duguer gneiss is the only proved gneiss in Qiangtang region upto now, which is exposed at Duguer mountain (peak, 6208m above sea level), Gaize county, and is confined by faults. An E—W oriented thrust fault zone is its south boundary, which is more than 200m wide and makes the gneiss overthrust on upper Carboniferous strata and Tertiary red beds southwardly. On the east and north sides of the gneiss are upper Carboniferous strata. The gneiss occurs as a triangle form with a long E—W trending bottom line (about 20km) and a height about 10km in S—N direction, which is the main part of Duguer Duguer mountain.Duguer gneiss consists of two rocks types, i.e. granitic gneiss (the dominant component) and amphibole\|plagioclase gneiss. The latter one occurs as a group of nearly E—W trending dikes with clear boundary, which are obviously late basic dikes that intruded into granite. Granitic gneiss is composed of porphyroclast granitic gneiss, banded granitic gneiss, gneissoid granite and granitic mylonite. Both granitic and amphibole\|plagioclase gneisses have been undergone same type and same degree metamorphism and deformation. The typical mineral assemblage of the former gneiss include quartz(30%), microcline(25%),plagioclase(30%), two mica (biotite +muscovite,13%) and the accessory minerals such as zircon, magnetite, and apatite etc. The main oxide contents of the granitic gneiss are (average of three samples) 73 53% SiO\-2, 12 9% Al\-2O\-3, 1 57% FeO, 0 52% MgO, 3 24%Na\-2O and 0 22% K\-2O. The REE distribution pattern shows typical features of granite, i.e. LREE enrichment, HREE depletion and rather strong negative Eu anomaly.
文摘It bas been considered that large\|scale basic igneous activities are related to results of the break\|up of paleo\|continent. Basic magmatism could record the dynamics information for orogenic process. Thus, studying it can help us to reconstruct the forming and evolution process of continental orogenic zone.The basic igneous zone in the central part of Qiangtang, Tibet, starts at the Sino\|Indian border in the west and ends at Shuanghu region in the east, being over 800km long and several to more than 100km wide. Based on published data, there are coeval basic magmatic activities with similar features in Sanjiang region, Western Yunnan and Thai\|Malaysian Peninsula. the basic dykes from Boyamalong to Qomu in central Qiangtang occur in swarms with E\|W trending and are more than one thousand in number. Single or composite igneous body is 1 to 7 km long and 0.3 to 3 km wide, being of the area of 0.3 to 20km\+2 . The total exposed area of the dykes is more than 400km\+2 . The country rocks of the intrusives are the upper Carboniferous Mushirbuka group, which consists of rift\|type deposits containing glaciomarine petromictic conglomerates.No basic dyke has been found in the strata since late Permian (Mokou Period)
