Geochemical Features of Lead and Sulfur Isotope of Yinchanggou Pb-Zn Deposit in Ningnan County, Sichuan Province, China

2013 ◽  
Vol 868 ◽  
pp. 34-37
Author(s):  
Ying Shu Li ◽  
Da Qing He ◽  
Ting Yin Hu ◽  
Jiao Jiao Chen ◽  
Dong Ming Yang ◽  
...  
Keyword(s):  
Sulfur Isotope ◽  
Mining Area ◽  
Mean Value ◽  
Sichuan Province ◽  
Material Source ◽  
Ore Deposit ◽  
Average Value ◽  
Lead Zinc ◽  
Sulphur Isotopic Composition ◽  
Orogenic Zone

inchanggou lead-zinc mining area, Ningnan county, Sichuan province is a medium reserves ore deposit in recent years. In order to study origin of the deposit,lead and sulfur isotopic geochemical features of the deposit must be research. In the deposit,mean value of 206Pb／204Pb of 9 samples is 0.285 (from 18.116 to 18.401), mean value of 207Pb／204Pb is 0.098 (from 15.658 to 15.756),and mean value of 208Pb／204Pb is 0.635 (from 38.249 to 38.884).which show lead of the ore deposit come main from upper earth's crust and few from orogenic zone. Average value is δ34S in the lead-zinc ore is 15.02 per thousand(from 5.8 per thousand to 20.32 per thousand), with positive value of sulphur isotopic composition. It is shown as heavy sulfur-rich, which is similar with composition characteristics of δ34S of seawater evaporate. The deposit is a strata-bound deposit with multi-material source.

Equilibrium Temperature Calculation of the Sulfur Isotope in Dongzhongla Pb-Zn Deposit in Tibet

2015 ◽  
Vol 1092-1093 ◽  
pp. 1394-1397
Author(s):  
Guang Chun Fei ◽  
Yi Fan Yu ◽  
Ke Qiang Hua
Keyword(s):  
Sulfur Isotope ◽  
Equilibrium Temperature ◽  
Mining Area ◽  
Isotopic Equilibrium ◽  
The North ◽  
Geological Conditions ◽  
Typical Type ◽  
Lead Zinc ◽  
Block Based ◽  
Exploration Area

The Dongzhongla Pb-Zn deposit, a newly-discovered medium-sized deposit, is located in the north margin of the eastern Gangdese, central Lhasa block. Based on the analysis of the ore-forming geological conditions in this deposit, sulfur isotope of this deposit were analyzed, and S isotopic equilibrium temperature of mineral pairs (sphalerite and galena) were calculated. This study has shown that the sulfur isotopic equilibrium temperature of sphalerite and galena in Dongzhongla Pb-Zn deposit ranged from 185℃ to 296℃. It indicated that the equilibrium temperature decreased gradually from the skarn stage to sulfide stage. The equilibrium temperature can be used as the reference of metallogenic temperature for Dongzhongla Pb-Zn deposit. DongzhongLa deposit is the typical type of skarn Lead-zinc deposit. East of the Dongzhongla mining area is the priority exploration area.

Geochemical Features of Cherts of Yinchanggou Pb-Zn Orefield in Ningnan County, Sichuan Province, China

2013 ◽  
Vol 807-809 ◽  
pp. 2155-2158 ◽  
Author(s):  
Ying Shu Li ◽  
Yi Ke Zhang ◽  
Cheng Lin Yang ◽  
Jiao Jiao Chen ◽  
Dong Ming Yang ◽  
...  
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Mining Area ◽  
Major Elements ◽  
Sichuan Province ◽  
Light Rare Earth ◽  
Dengying Formation ◽  
Lead Zinc ◽  
Upper Sinian

In Yinchanggou lead-zinc mining area, Ningnan county, Sichuan province, there are many cherts in Dengying formation of upper Sinian series. By means of research on geological survey on field, petrology, major elements, trace elements and rare earth elements of the cherts, its proved that the cherts are chiefly composed of opal, jade and quartz, total amount of rare earth elements of the cherts for 1.36× 10-6, which is the light rare earth enrichment. For Fe/Ti is between 48.751and 194.44, (Fe+Mn)/Ti between 51.143 and 197.22, Al/(Al+Fe+Mn) between 0.03 per cent, the cherts is mainly formed by hydrothermal sedimentation.

scholarly journals Thinner Sea Ice Contribution to the Remarkable Polynya Formation North of Greenland in August 2018

2021 ◽  
Author(s):  
Xiaoyi Shen ◽  
Chang-Qing Ke ◽  
Bin Cheng ◽  
Wentao Xia ◽  
Mengmeng Li ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ice Cover ◽  
Reanalysis Data ◽  
Mean Value ◽  
Ocean Model ◽  
North Coast ◽  
Average Value ◽  
The North ◽  
Wind Sea ◽  
The One

AbstractIn August 2018, a remarkable polynya was observed off the north coast of Greenland, a perennial ice zone where thick sea ice cover persists. In order to investigate the formation process of this polynya, satellite observations, a coupled ice-ocean model, ocean profiling data, and atmosphere reanalysis data were applied. We found that the thinnest sea ice cover in August since 1978 (mean value of 1.1 m, compared to the average value of 2.8 m during 1978–2017) and the modest southerly wind caused by a positive North Atlantic Oscillation (mean value of 0.82, compared to the climatological value of −0.02) were responsible for the formation and maintenance of this polynya. The opening mechanism of this polynya differs from the one formed in February 2018 in the same area caused by persistent anomalously high wind. Sea ice drift patterns have become more responsive to the atmospheric forcing due to thinning of sea ice cover in this region.

Resistance of a Ship Undergoing Oscillatory Motion

2010 ◽  
Vol 54 (02) ◽  
pp. 120-132
Author(s):  
Lawrence J. Doctors ◽  
Alexander H. Day ◽  
David Clelland
Keyword(s):  
Finite Depth ◽  
Mean Value ◽  
Wave Resistance ◽  
General Effect ◽  
Towing Tank ◽  
Ship Model ◽  
Average Value ◽  
Unsteady Effects ◽  
Oscillatory Cycle ◽  
Resistance Tests

In this paper, we describe extensions to the research of Doctors et al. (Doctors, L. J., Day, A. H., and Clelland, D., 2008, Unsteady effects during resistance tests on a ship model in a towing tank, Journal of Ship Research, 52, 4, 263–273) and Day et al. (Day, A. H., Clelland, D., and Doctors, L. J., 2009, Unsteady finite-depth effects during resistance tests in a towing tank, Journal of Marine Science and Technology, 14, 3, 387–397) in which the oscillations in the wave resistance during the constant-velocity phase of a towing-tank resistance test on a ship model were measured and predicted, in the cases of relatively deep and relatively shallow water. In the current study, the ship model was towed with a harmonic velocity component superimposed on the usual constant forward velocity. This work constitutes a first step in the understanding of the unsteady hydrodynamics of a racing shell (rowing boat). We show here that the unsteady wave resistance varies considerably from the traditional (steady) average value. Indeed, the wave resistance is frequently negative during part of the oscillatory cycle. However, the general effect is an increase in the temporal mean value of the wave resistance; this suggests that every effort should be made to reduce the unsteadiness of the motion. We also demonstrate that the unsteady wave-resistance theory provides an excellent prediction of the measured effects summarized here. These predictions are often within a few percent of the measured values of the resistance.

scholarly journals POPULATION STRUCTURE AND PRODUCTION OF COPAIBA OLEORESIN BETWEEN VALLEYS AND HILLSIDES OF THE MINING AREA OFTROMBETAS RIVER - PARÁ1

2016 ◽  
Vol 40 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Jonas Gebara ◽  
Antenor Pereira Barbosa ◽  
Isabel Maria Gonçalves Azevedo ◽  
Bruno Oliva Gimenez
Keyword(s):  
Population Structure ◽  
Forest Inventory ◽  
Sustainable Management ◽  
Natural Populations ◽  
Mining Area ◽  
National Forest ◽  
The South ◽  
Potential Production ◽  
Average Value ◽  
Bauxite Ore

ABSTRACT We aimed in this work to study natural populations of copaiba (Copaifera multijuga Hayne) on the Monte Branco mountain at Porto Trombetas-PA, in order to support sustainable management and the exploitation of oleoresin from copaiba. We studied the population structure of copaiba on hillsides and valleys of the south face of Monte Branco, within Saracá Taquera National Forest, where bauxite ore was extracted in the biennium 2013-2014 by Mineração Rio do Norte (MRN). We produced a 100% forest inventory of the specie and of oleoresin extraction in order to quantify the potential production of the remaining area. The density of copaiba individuals with DBH > 30 cm was 0.33 individuals per hectare in the hillside and 0.25 individuals per hectare in the valley. Both environments presented a density of 0.28 individuals per hectare. The average copaiba oleoresin yield was 0.661±0.334 liters in the hillside and 0.765±0.280 liters in the valley. The average value of both environments together (hillside and valley) was 0.714±0.218 liters. From all individuals with DBH over 30 cm, 38 (58%) produced some amount of oleoresin, averaging 1.113±0.562 liters in the hillside, 1.329±0.448 liters in the valley and 1.190±0.355 liters in both environments together. The results show the need for planning the use of the surroundings of the study area in order to reach the required volume of copaiba to make feasible the sustainable management of oleoresin extraction in the region.

scholarly journals Phytoplankton community structure and it’s relationships with water quality in Bangka Island, Indonesia

2021 ◽  
Vol 26 (1) ◽  
pp. 37-44
Author(s):  
Muh Yusuf ◽  
Robin Robin ◽  
Wahyu Adi ◽  
Mu’alimah Hudatwi ◽  
Widianingsih Widianingsih ◽  
...  
Keyword(s):  
Water Quality ◽  
Phytoplankton Community ◽  
Environmental Changes ◽  
Total Suspended Solid ◽  
Mining Area ◽  
Suspended Solid ◽  
Test Analysis ◽  
Mining Site ◽  
Average Value ◽  
Primary Producer

Phytoplankton plays an important role in primary productivity in marine environment. Various environmental changes in coastal area will impact the water quality and their phytoplankton compositions. The purpose of this study is to examine the abundance of phytoplankton from two different sites, i.e Tanah Merah (close to mining site) and Semujur Island (away from mining site) in Bangka Island. Phytoplankton and water sample were collected on June- August 2018. Water quality was measured using water quality checker, whereas the phytoplankton was identified under the microscope with a magnification of 100x. Non-parametric Kruskal test and T-test analysis was performed to determine the abundance, diversity, uniform, and dominance of phytoplankton between Sites, respectively. Statistical analyses showed the abundance of phytoplankton at Semujur Island was significantly higher than that at Tanah Merah (p = 0.003). In additions the diversity, uniform, and dominance were also significantly different between sites (all p <0.05). In Semujur Island, Diatoms (Thalassiothrix, Chaetoceros and Thalassionema) were more dominants than the Dinophyceae group. However, in Tanah Merah, the genera Ceratium belong to class Dinophyceae was more dominant than the class Bacillariophyceae. These results performed that the phytoplankton in Tanah Merah and Semujur Island was affected by environment, in this case the mining area. The water quality in Semujur Island (non-mining Area) might have good quality than in Tanah Merah (mining area). The average value of turbidity and Total Suspended Solid in Tanah Merah Waters causes low abundance of phytoplankton. It can be concluded that tin mining can disrupt the abundance and composition of phytoplankton as a primary producer of waters.

scholarly journals Rational size and stability analysis of horizontal isolated pillars in deep mining from caving to filling method

2021 ◽  
Vol 303 ◽  
pp. 01040
Author(s):  
Fan Feng ◽  
Xibing Li ◽  
Shaojie Chen ◽  
Dingxiao Peng ◽  
Zhuang Bian
Keyword(s):  
Numerical Simulation ◽  
Three Dimensional ◽  
Mining Area ◽  
Middle Section ◽  
Deep Mining ◽  
Metal Mines ◽  
Lead Zinc ◽  
Filling Method ◽  
Zinc Mine ◽  
Cut And Fill

For mining using the caving and filling methods in metal mines, determining a suitable size for the isolated pillars—the connecting part of the extension from shallow to deep—is crucial for ensuring safety and efficiency. Considering actual cases involving deep caving and cut-and-fill mining in the Chifeng Hongling lead-zinc mine in Inner Mongolia, China, the reserved thickness range of the horizontal isolation layer is obtained via theoretical analysis. On this basis, the pre-processing software HyperMesh is used to build a high-precision hexahedral grid model of the mining area, and the three-dimensional geological model of the mining area is imported into the finite-difference software FLAC3D. The stress field, displacement field, and plastic area evolution law of pillars (horizontally isolated pillars and adjacent rib pillars) in the stope of the ninth middle section after excavation are analyzed via numerical simulation inversion of the selected scheme of horizontal isolated pillars. The numerical simulation results show that the scheme employed to retain the upper horizontal isolated pillars in the ninth middle section involves reserving thicknesses of 8 m and 32 m at average ore body thicknesses of 15 m and 35 m, respectively. These results can provide theoretical guidance and a basis for safe and efficient mining of deep metal mines.

scholarly journals Mandibular Morphology Differences Between Edentulous And Dentate Assessed By Panoramic Radiographs

2017 ◽  
Vol 16 (2) ◽  
Author(s):  
Lidya Irani Nainggolan ◽  
Aude Layakni Girsang
Keyword(s):  
Panoramic Radiography ◽  
Mechanical Stimulus ◽  
Mean Value ◽  
Notch Depth ◽  
Cross Sectional ◽  
Gonial Angle ◽  
Average Value ◽  
Mandibular Morphology ◽  
Edentulous Patients ◽  
Ramus Height

Introduction: Facial profile can be influenced by edentulous condition that can change mandibular morphology that can affect mastication, digestion and psychosocial life. Edentulism causes absence of occlusal mechanical stimulus, decrease the activity of mastication muscles and increase mandibular bone resorption. These changes can be assessed using panoramic radiography by looking at the vertical dimension of the head of the condyle and its shape, ramus, and the angle of the mandible. The aim of the study was to assess the mean value and differences of mandibular morphology in edentulous and dentate patients using panoramic radiography. Materials and Methods: This was an analytical study with cross-sectional approach using purposive sampling methods. 50 dentate and edentulous patients who came to Dentistry Hospital of University of Sumatera Utara were used as sample. Data analysis was done using Independent T test and MannWhitney test. Results: Results showed that the average value of gonial angle, ramus height, condylar height, antegonial notch depth and ramus notch depth in edentulous patients were 125,38 ± 9,51; 35.98mm ± 4.26; 5.58mm ± 0.90; 2.11mm ± 1.04; and 2.73mm ± 0, 88, and the results showed that the average value of mandibular morphology in dentate patients were 123.34 ± 7.07; 38.15mm ± 3.23; 6.95mm ± 1.25; 1.41mm ± 0.77; and 2.15mm ± 0.59. Conclusion(s): There were significant differences in the values of ramus height, condylar height, antegonial notch depth, and ramus notch depth. Difference was also found in gonial angle value, but was not statistically significant.

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