Advanced Materials Research Vols. 962-965

Abstract: Because of thick coal seam mining method selection is not only affected by coal seam geological conditions, but also limited by workers, and not fully utilization of experts` experience, the effect of tradition coal mining method selection methods are not ideal. The thick coal seam mining method prediction model based on artificial neural network (TCSMMPM-ANN) was established through the analysis of thick coal seam mining by using Levenberg – Marquardt (L-M) improved algorithm to train network, the simulation results of network test show that this model can provide a new research idea for thick coal seam mining method optimal selection and face economic and technical index prediction, it will have a broad prospect in thick coal mining.

Abstract: ZhaoJinggou Nb-Ta deposit was discovered in 1967.After a series of exploration, a summary report of preliminary exploration of ZhaoJinggou Nb-Ta deposit was submitted. The detail exploration was carried out in this mineral aera in 2010.The deposit was sited in the middle part of the northern margin of north China platform, YinShan lifted block and north wing of Daqingshan anticlinorium. A series of metamorphose rocks of Proterozoic to Neoproterozoic were widely distributed in this area. Nb-Ta veins intruded into the structural fissure of dark grey pebbled metamorphic sandstone of Middle Carboniferous Shuanmazhuang Formation. Through verification of deep drilling, it exsited a larger decalcified feldspathized granodiorites and albite granites, which had a relationship with the formation of these veins. The intensity of albitization determined the grade of Nb-Ta minerals.And albitization caused the richment of other rare elements, which had a comprehensive utilization value. Based on the detailed exploration, the Zhaojinggou deposit should have a good mineralize perspective, which may exist the large alkaline albite lithium mica granite Nb-Ta deposits in deep or outer-ring of mining area.

Abstract: Geothermal energy is an important type of renewable energy. It can be easily mined at low cost, and has the advantages of no pollution and recycling utilization. The exploitation of geothermal energy can bring about significant economic, social and environmental benefits. The base for geothermal energy exploitation is the exploration of geothermal field. Analysis of the geological background of regional structure and heat control, collect adjacent areas geological data in Inner Mongolia with the use of electromagnetic sounding.

Abstract: Due to the incomplete decision information of mining projects, a new interval evaluation method basing on D-S evidence theory is applied to comprehensive evaluation of mineral resources. Index dates of evaluation system are assigned by the basic probability function . The probability value related to weights and membership grade for indexes .The Bays interval is estimated through evidence combination of dates and computed in decision making. Application to assessment of mining right transaction information are presented to demonstrate the effectiveness of the method.

Abstract: In the control of palaeogeomorphology and fracture, multistage slope break zones are developed in Beixi Slope. After the analyses of the structural-paleogeomorphologic features, according to the relationships between slope break zones and subsags, we divide the slope break zones into three cells—inner slope break zones, middle slope break zones and outer slope break zones. Compared with the outer and middle slope break zones, the fault block traps are richly developed in the inner slope break zones, which is nearer to the oil generating depressions. And the conditions of reservoirs there are good. So they are excellent for hydrocarbon accumulation and preservation with good oil accumulating conditions.

Abstract: Using contrast analytic method and take the coal-control structural pattern as the master line summarized the differences of coalfield structure characteristic in Jilin Province. Generally speaking, in the north, the extensional action is the most pattern, however, in the south of Jilin, the main structural pattern is compressions. In North, fault and block combination is the main pattern, the coal distribution range is relatively bigger; however, In south, the mainly are compression patterns such as the combination of reverse and thrust, thus, coal measures are obviously destructed and have smaller extent. Moreover, the structure difference above between south and north is also closely with their tectonic position and experience of tectonic evolution.

Abstract: In order to clarify the relationship between fractures and gas accumulation, using data of cores, image logs and experimental analysis, we analyzed the fracture genetic types, development characteristics, controlling factors, distribution rules and formation periods. And then, by combining the evolution of source rock, activity periods of gas source faults and the evolution of cap rock sealing ability in the study area, we discussed the relationship between tectonic fractures and gas accumulation. The results show that there exist primary fracture and secondary fracture in the volcanic rocks of Yingcheng Formation in Songliao Basin. Between the two types, the secondary facture is dominant. Tectonic fractures are controlled by lithology, lithofacies and faults in the plane, and by unconformities vertically, with the characteristics of distribution of cycles. The tectonic fractures formed in three phases, wherein the second period coincides with the hydrocarbon generation peak period. During the second period, gas source faults are active and cap rock had a better sealing ability. This period is the main hydrocarbon accumulation stage in the study area.

Abstract: The Huajian gold deposit is located in the metallogenic belt of the northern part of the North China block. This deposit's ore bodies are mainly hosted in metamorphosed Neoarchean and Mesoproterozoic sedimentary rocks, of which Mesozoic volcano-intrusive complexes are closely associated with the Gold mineralization. The FIs of the Huajian deposit are primarily aqueous FIs with minor gas FIs. The pure gas or liquid FIs are very few. The ore-forming fluids were characterised by moderate–low temperature, low salinity and high oxygen fugacity and belonged to an H₂O–NaCl ± CO₂ system. The FIs in quartz veins primarily developed in temperature intervals of 202–380°C, 191–407°C and 170–307°C., corresponding to salinities of 3.85wt.% to 11.23 wt.%, 3.69wt.% to 10.99 wt.% and 2.06wt.% to 17 wt.% NaCl eq.., respectively. The trapping pressures of the FIs from high temperature fluids in the quartz veins are 10-90 MPa, corresponding to depths of 1.0–10 km, assuming a density of the overlying rocks of 0.54 g/cm3–0.98 g/cm3. Multiple stages of phase separation or immiscibility of ore-forming fluid was critical for the formation of the Huajian deposit.

Abstract: Volcanic rocks of Yixian Formation were widely distributed in western Liaoning. The Yixian volcanic cycle of early Cretaceous in the Chaoyang basin can be divided into two subcycles. The first subcycle is composed of basalt, basalt andesite and andesite. The second subcycle is composed of trachyandensite and trachyte. The volcanic rocks are characterized by high SiO₂, Al₂O₃, K₂O and Na₂O, and comparatively low TiO₂ components. The volcanic rocks are obviously enriched in incompatible elements, and depleted in compatible elements. The ∑REE of volcanic rocks is high and rich in LREE. The spider patterns are the right-incline, there is a slight low Eu negative abnormality and low Ce negative abnormality. The characteristics show that volcanic rocks of Yixian Formation belong to the high-K calc-alkaline magmatic serious. Comprehensive study shows that the volcanic rocks of Yixian Formation were generated in response to lithosphere extension in the continent intraplate orogenic belt.

Abstract: Halegati Fe-Cu deposit of skarn was located in the Boluokenu metallogenic belt. With the research of the geochemistry characteristic of granodiorites, the results showed that the rocks belonged to I type granite with the features of siliceous, metaluminous, low magnesium , high-k and alkalic. The intrusive rocks had a close association with the mineralization, which had the features of enrichment of large-ion lithophile elements (K, Rb, Ba, Th) and relative depleted in high-field strength elements (Nb, Ta, P, Ti).The intrusive rocks in Halegati had the characteristic of strongly differentiation between LREE and HREE and negative Eu anomalies obviously. The REE distribution curves had the right types. The intrusive rocks were formed in the environment of volcanic arc, which produced in the tectonic setting of supra subduction zone.