2001 Vol. 34 No. 4
Abstract：
Northern Qilian mountain is one of a famous orogenic belts in Caledonides.It is mainly focused on formation and on underthrust-collsion and interactionental orogenic tectioncs of the main mountain-building period in the past reports.After the regional geological surveying at the western part of northern Qilian mountain, the author discovered a set of bedding detachment fault, ductile shear zone, flow cleavage and recum bent folds.In this paper, structure form, assembly, the characters of kinetics and dynamic and corresponding formation are analyzed and discussed in detail.Based on this, the authors pointed out all these are a synkinematic normal fault extensional structure group which are corresponding with the formation of rift basin in pre-orogenic phase.
Northern Qilian mountain is one of a famous orogenic belts in Caledonides.It is mainly focused on formation and on underthrust-collsion and interactionental orogenic tectioncs of the main mountain-building period in the past reports.After the regional geological surveying at the western part of northern Qilian mountain, the author discovered a set of bedding detachment fault, ductile shear zone, flow cleavage and recum bent folds.In this paper, structure form, assembly, the characters of kinetics and dynamic and corresponding formation are analyzed and discussed in detail.Based on this, the authors pointed out all these are a synkinematic normal fault extensional structure group which are corresponding with the formation of rift basin in pre-orogenic phase.
Abstract：
Influenced by the special topography and climate, hydrothermal factors of different places in northwest area don't match completely.In northwest area, precipitation of high mountains is rich and thermal is in sufficient, which is contrary to that in side basin.A bominable climate affects the growth of vegetation and soil.As a result, superficial ecosystem becomes very fragile and a serial of ecological and environmental questions are presented including prominent drought, degeneration of vegetation recovery, serious soil erosion, increasing of desertification and soil salinization and so on.In this paper, by analyzing the thermal factors in research area the author clarifies the main ecological and environmental questions and presents some measures and policies of ecological environment recovery.
Influenced by the special topography and climate, hydrothermal factors of different places in northwest area don't match completely.In northwest area, precipitation of high mountains is rich and thermal is in sufficient, which is contrary to that in side basin.A bominable climate affects the growth of vegetation and soil.As a result, superficial ecosystem becomes very fragile and a serial of ecological and environmental questions are presented including prominent drought, degeneration of vegetation recovery, serious soil erosion, increasing of desertification and soil salinization and so on.In this paper, by analyzing the thermal factors in research area the author clarifies the main ecological and environmental questions and presents some measures and policies of ecological environment recovery.
Abstract：
In this paper, a genetic analysis on complecation rock mass for the right dam abutment of a hydropower station on the Lancangjiang River permitus to classify the rock mass accurately.The result of compare quality index of rock mass classfication with other means of rock mass classifications is actually.
In this paper, a genetic analysis on complecation rock mass for the right dam abutment of a hydropower station on the Lancangjiang River permitus to classify the rock mass accurately.The result of compare quality index of rock mass classfication with other means of rock mass classifications is actually.
2001, 34(4): 23-29.
Abstract：
There are rich copper ore resources and complete types of copper ore deposits in Gansu, China, but reserves explored is not concordant with quantity of explored mineral occurrences and zone as well as in ten sity of mineralization, so it is quite large in potential capacity of prospecting copper ore deposits.In this paper a concluding analysis had been tried to make about the mineral characteristic of Gansu' copper ore deposits, and a program of six types for Gansu' copper ore deposits divided by host rocks on the basis of referring to fo reign and domestic experience of successful exploration in copper deposits.Besides, a new train of thought for prospecting had been suggested on main metallogenic provinces zones.
There are rich copper ore resources and complete types of copper ore deposits in Gansu, China, but reserves explored is not concordant with quantity of explored mineral occurrences and zone as well as in ten sity of mineralization, so it is quite large in potential capacity of prospecting copper ore deposits.In this paper a concluding analysis had been tried to make about the mineral characteristic of Gansu' copper ore deposits, and a program of six types for Gansu' copper ore deposits divided by host rocks on the basis of referring to fo reign and domestic experience of successful exploration in copper deposits.Besides, a new train of thought for prospecting had been suggested on main metallogenic provinces zones.
Abstract：
Tongyugou cupper deposit located at the Triassic sedimentary basin of Hainai (to the South of Qinghai Lake) occures in a olistostrome felt with E-W orientation and in the transitional position from marene sedimentary series to volcanic-sedimentary series, which is characterized by typical dedded or ebodies and association with wrigglites and silicon-rich sedimentary rocks.On the basis of the sedimentary formation, sedimentary facies of ore-bearing series and the nature of the volcanic rocks, the tectonic setting of the deposit is considered to be spreading-subsidence basin existting in continental margin.The contrast to different stratiform sulfide deposits indicate Tongyugou depositis between Sedex type and Besshi type but closer to the latter.
Tongyugou cupper deposit located at the Triassic sedimentary basin of Hainai (to the South of Qinghai Lake) occures in a olistostrome felt with E-W orientation and in the transitional position from marene sedimentary series to volcanic-sedimentary series, which is characterized by typical dedded or ebodies and association with wrigglites and silicon-rich sedimentary rocks.On the basis of the sedimentary formation, sedimentary facies of ore-bearing series and the nature of the volcanic rocks, the tectonic setting of the deposit is considered to be spreading-subsidence basin existting in continental margin.The contrast to different stratiform sulfide deposits indicate Tongyugou depositis between Sedex type and Besshi type but closer to the latter.
2001, 34(4): 43-52.
Abstract：
The studies on spatial-temporal distribution, sedimentary formation, Cu-bearing property and geochemical parameters indicate that Cu-bearing banded iron-formation from the western part of Northern Qilian aere was formed between the period of two basic volcanic eruption under Proterozoic rift.The pre-enrichment ore-forming element-Cu came maily from the underlying basic volcanic rocks.
The studies on spatial-temporal distribution, sedimentary formation, Cu-bearing property and geochemical parameters indicate that Cu-bearing banded iron-formation from the western part of Northern Qilian aere was formed between the period of two basic volcanic eruption under Proterozoic rift.The pre-enrichment ore-forming element-Cu came maily from the underlying basic volcanic rocks.
Abstract：
In Yanchang formation period, the environment is favorable to the development of the lake delta.The delta front mainly developed in Chang 6, which includes microfacies, such as distributary channel sandbodies, river mouth bars, distal bars and so on.The pore spaces are completely dominated by primary porosity and pores, vogs and fractures with secondary origination.Study indicates that the formation and evolution of the porosity are controlled by diagenesis.The diageneses mainly comprise cementation, compaction and dissolition.Cementation, compaction are unfavorable for the evolution of the porosity.Dissolition is favorable for secondary porosity, thus forming available reservoirs in some sections of low porous and low permeable clastic rocks.According to synthesize evaluate, the distributary channel sandbodies and river mouth bars are best reservoir.
In Yanchang formation period, the environment is favorable to the development of the lake delta.The delta front mainly developed in Chang 6, which includes microfacies, such as distributary channel sandbodies, river mouth bars, distal bars and so on.The pore spaces are completely dominated by primary porosity and pores, vogs and fractures with secondary origination.Study indicates that the formation and evolution of the porosity are controlled by diagenesis.The diageneses mainly comprise cementation, compaction and dissolition.Cementation, compaction are unfavorable for the evolution of the porosity.Dissolition is favorable for secondary porosity, thus forming available reservoirs in some sections of low porous and low permeable clastic rocks.According to synthesize evaluate, the distributary channel sandbodies and river mouth bars are best reservoir.
2001, 34(4): 61-66.
Abstract：
The strata of Devonian in the north-west border of Wengxian country of yangtze region was explored by the authors during the surveying of the 1:5000 Buziba sheet and Lingjiang sheet.The results of reseach show that it may be divided in to four three-order sequences.And each sequence exists TST and HST.The first three-sequence didn't find LST and SMST.The last one has SMST.After sedimentary sequences contrast of the region, the stratigraphic framework of Devonian was bas built and analycised at north-west border in yangtze region.
The strata of Devonian in the north-west border of Wengxian country of yangtze region was explored by the authors during the surveying of the 1:5000 Buziba sheet and Lingjiang sheet.The results of reseach show that it may be divided in to four three-order sequences.And each sequence exists TST and HST.The first three-sequence didn't find LST and SMST.The last one has SMST.After sedimentary sequences contrast of the region, the stratigraphic framework of Devonian was bas built and analycised at north-west border in yangtze region.
2001, 34(4): 75-80.
Abstract：
The method about orgnizing and managing spatial data, provided by MapObjects which is a kind of product of ESRI, is analized, at the same time the problems and disadvantages met when managing multi-layer, multi-theme spatial data saved distributedly is discussed, and then an available method is provided in this article.Furthermore, an improved model as well as algorithm is built, which has acquired a good purpose in applying.
The method about orgnizing and managing spatial data, provided by MapObjects which is a kind of product of ESRI, is analized, at the same time the problems and disadvantages met when managing multi-layer, multi-theme spatial data saved distributedly is discussed, and then an available method is provided in this article.Furthermore, an improved model as well as algorithm is built, which has acquired a good purpose in applying.
