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Alteration and Mineralization in the Xiaoxinancha Porphyry Copper Deposit, Yianbin, China: Fluid Inclusion and Sulfur Isotope Study (중국 연변 쇼시난차 반암동 광상의 광화작용 및 변질작용: 유체포유물 및 황동위원소 연구)

  • Seong-Taek Yun;Chil-Sup So;Bai-Lu Jin;Chul-Ho Heo;Seung-Jun Youm
    • Economic and Environmental Geology
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    • v.35 no.3
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    • pp.211-220
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    • 2002
  • The Xiaoxinancha Cu-Au deposit in the Jilin province, located in NNE 800 km of Beijing, is hosted by diorite. The ore mineralization of Xiaoxinancha Cu-Au deposit show a stockwork occurrence that is concentrated on the potassic and phyllic alteration zones. The Xiaoxinancha Cu-Au deposit in the south is being mined with its reserves grading 0.8% Cu, 3.64 g/t Au and 16.8 g/t Ag and in the north, grading 0.63% Cu, 3.80 g/t Au and 6.8 glt Ag. The alteration assemblage occurs as a supergene blanket over deposit. Hydrothermal alteration at the Xiaoxinancha Cu-Au deposit is centered about the stock and was extensively related to the emplacement of the stock. Early hydrothermal alteration was dominantly potassic and followed by propylitic alteration. Chalcocite, often associated with hematite, account for the ore-grade copper, while chalcopyrite, bornite, quartz, epidote, chlorite and calcite constitute the typical gangue assemblage. Other minor opaque phases include pyrite, marcasite, native gold, electrum, hessite, hedleyite, volynskite, galenobismutite, covellite and goethite. Fluid inclusion data indicate that the formation of this porphyry copper deposit is thought to be a result of cooling followed by mixing with dilute and cooler meteoric water with time. In stage II vein, early boiling occurred at 497$^{\circ}$C was succeeded by the occurrence of halite-bearing type III fluid inclusion with homogenization temperature as much as 100$^{\circ}$C lower. The salinities of type 1II fluid inclusion in stage II vein are 54.3 to 66.9 wt.% NaCI + KCI equiv. at 383$^{\circ}$ to 495$^{\circ}$C, indicating the formation depth less than 1 km. Type I cupriferous fluids in stage III vein have the homogenization temperatures and salinity of 168$^{\circ}$ to 365$^{\circ}$C and 1.1 to 9.0 wt.% NaCI equiv. These fluid inclusions in stage III veins were trapped in quartz veins containing highly fractured breccia, indicating the predominance of boiling evidence. This corresponds to hydrostatic pressure of 50 to 80 bars. The $\delta$$^{34}S$ value of sulfide minerals increase slightly with paragenetic time and yield calculated $\delta$$^{34}S_{H2S}$ values of 0.8 to 3.7$\textperthousand$. There is no mineralogical evidence that fugacity of oxygen decreased, and it is thought that the oxygen fugacity of the mineralizing fluids have been buffered through reaction with magnetite. We interpreted the range of the calculated $\delta$$^{34}S_{H2S}$ values for sulfides to represent the incorporation of sulfur from two sources into the Xiaoxinancha Cu-Au hydrothermal fluids: (1) an isotopically light source with a $\delta$$^{34}S$ value of I to 2$\textperthousand$, probably a Mesozoic granitoid related to the ore mineralization. We can infer from the fact that diorite as the host rock in the Xiaoxinancha Cu-Au deposit area intruded plagiogranite; (2) an isotopically heavier source with a $\delta$$^{34}S$ value of > 4.0$\textperthousand$, probably the local porphyry.

Effect of Feeding Aflatoxin and Vitamin $D_3$ on Body Weight Gain, Nutrient Utilization, Tibia Mineral and Serum Characteristics of Broiler Chicks (Aflatoxin과 비타민$D_3$ 급여(給與)가 브로일러 병아리의 증체(增体), 영양소이용율(營養素利用率), 경골무기물(脛骨無機物) 및 혈청성상(血淸性状)에 미치는 영향(影響))

  • Chiang, Yun Hwan;Cheon, Jin Seock;Yeo, Young Soo
    • Current Research on Agriculture and Life Sciences
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    • v.2
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    • pp.68-76
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    • 1984
  • A $2{\times}4$ factorial study was carried out to investigate the interaction of aflatoxin and vitamin $D_3$ in broiler chicks. The day-old 336 chicks were allocated to triplicate 8 treatments. The 0 or 0.5 ppm of aflatoxin $B_1$ (AFB) and 0, 500, 1,000 or 1,500 IU/Kg of vitamin $D_3$ (VD) were supplemented to the basal diet. There were no significant differences among treatments in respect to the body weight gain, feed intake, feed conversion, shank color, mortality and incidence of weak legs. The utilization efficiencies of dry matter, crude protein, ether extract, N-free extract and crude ash showed also no significant differences among treatments, respectively. The mean utilization efficiency of crude fiber in AFB group was lower than that in normal groups (P<.01). However, no significant difference was found among groups fed different levels of VD, and no interaction between AFB and VD was found. The utilization efficiency of Ca in AFB group was somewhat higher than that in normal group without statistical significance, and the similar values were found among groups fed different VD. The utilization efficiencies of P and Na were not significantly different among treatments, respectively. The tibia ash appeared to be similar among treatments fed different levels of AFB and VD. However, the Ca content in tibia of birds fed 0.5 ppm of AFB was higher than that of normal chicks (P<.05). The slightly increasing trend was shown in Ca contents when fed increasing revel of VD, and the interaction between AFB and VD was recognized(P<.01). The P content of tibia was increased by feeding AFB(P<.05). However, there was no significant difference among groups fed different level of VD and no interaction between AFB and VD in respect to the P content of tibia. Feeding AFB did not affect the Na content in tibia. However, there was a highly significant difference among groups fed different levels of VD(P<.01), the highest values were at 1,000 IU/Kg group, and the interaction between AFB and VD was not significant. The Ca content in serum of birds fed AFB was higher than in control group (P<.01). The Ca of serum increased when fed more VD, although no significance was found among groups, and there was an interaction between AFB and VD(P<.05). The P content of serum showed no significant difference among treatments. The alkaline phosphatase activity in serum of chicks fed AFB was higher than that of control group (P<.01). The enzyme activity increased slightly with increasing level of VD, however, there was no interaction between AFB and VD.

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Microbiological Studies on Feed Supplements (사료첨가제(飼料添加劑)의 미생물오염(微生物汚染)에 관(關)하여)

  • Park, Su Kyung;Tak, Ryun Bin
    • Current Research on Agriculture and Life Sciences
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    • v.4
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    • pp.132-140
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    • 1986
  • Eighty one products from 36 kinds of vitamin and mineral feed supplement collected during August, 1984 to February, 1985 were examined for microbiological contamination. In addition, 83 strains of coliform isolated from the samples were tested for the resistance to 8 kinds of antimicrobial drugs and distribution of R plasmid. General bacteria were detected in all of samples tested. Bacterial population was varied from less than 10 per gram of the sample to 1,400,000 per gram and 34 (42%) of 81 samples were contaminated with 100 to 1,000 cells per gram. Coliform isolation, which was more frequent in samples with larger number of general bacteria, was possible in 14 (17.3%) out of 81 samples tested and 6 (33.3%) out of 18 companies were coliform positive in their products. Forty one (49.4%) out of 83 coliform isolates were fecal coliform. The frequency of resistant strains was the highest to sulfadimethoxine (Sa) with 92.8% and followed by streptomycin (Sm, 67.5%), tetracycline (Tc, 50.6%), kanamycin (Km, 26.5%), chloramphenicol (Cm, 18.1%) and ampicillin (Am, 15.7%). No strain was resistant to nalidixic acid (Na) and gentamicin (Gm). The resistance frequency of fecal coliform strains were higher compare to non-fecal coliform strains. There were minimum inhibitory concentration (MIC) of $3,200{\mu}g/m{\ell}$ or higher in 7 strains to Am, 3 to Sm and 3 to Km, and 70 strains had MIC of $1,600{\mu}g/m{\ell}$ of higher to Sa while Tc had MICs from $1.6{\mu}g/m{\ell}$ to $400{\mu}g/m{\ell}$. All strains had MICs of $6.3{\mu}g/m{\ell}$ of lower to Na and $3.1{\mu}g/m{\ell}$ of lower to Gm. Seventy nine (95.2%) of 83 strains were resistant to one or more drugs tested. The most frequent resistance patterns were SaSm (14.5%) and followed by SaSmTc(12%), SaSmTcKm(8.4%) SaTc (8.4%) and SaSmKm (7.2%) ; total 19 different patterns were noted. Thirty two (40.5%) of 79 resistant strains were transferred all of a part of their resistance to Escherichia coli ML 1410. The frequency of transferable resistance was high in Am (100%) and Cm (80%) while low in Tc (38.1%), Sa (18.2%), Sm (17.9%) and Km (4.5%).

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Studies on the Effects of Antler Extract in Osteoporosis-Induced Rats I. Effects of Antler Extract on Hormones, Ca, P and ALP Levels in Osteoporosis-Induced Rats (녹용 추출물 투여가 골다공증 유발 Rat 에 미치는 효과에 관한 연구 I. 녹용 추출물 투여가 골다공증 유발 Rat 의 혈청내 호르몬, Ca, P, ALP 수준에 미치는 영향)

  • Kim, S. K;Kim, S. W.;Kim, M. S.
    • Korean Journal of Animal Reproduction
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    • v.24 no.2
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    • pp.179-188
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    • 2000
  • The present study was carried out in order to investigate the effects of antler extract on hormone concentration, Ca, P and alkaline phosphatase (ALP) levels in ovariectomized rats. Rats were ovariectomized bilaterally and were fed up with Ca- and P-free diet in order to induce osteoporosis. Osteoporosis was determined by the extent of density of bone mineral and lowering the concentrations of serum Ca and P. Male or female antler extract were administrated for 5 weeks to elucidate the protective and therapeutic effects for osteoporosis. The serum concentrations of estradiol, progesterone, calcitonin, osteocalcin, Ca and P, and the activities of ALP of ovariectomized rats were examined for 5 weeks. 1. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of the serum estradiol of the ovariectomized rat significantly decreased from 40.50$\pm$3.34 pg/$m\ell$ to 20.80$\pm$1.86 pg/$m\ell$ for 5 weeks, the levels of serum estradiol were a signigicant lower than those of control group (49.50$\pm$2.70~50.80$\pm$3.l3 pg/$m\ell$). 2. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum progesterone were didn't show significant differences. 3. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum calcitonin were a little higher than those of control group (0.64$\pm$0.03 ~0.68$\pm$0.04 pg/$m\ell$). 4. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum osteocalcin were little higher than those of control groups (0.28$\pm$0.02~0.31$\pm$0.02 ng/$m\ell$). In addition, the levels of serum osteocalcin of female antler extract administered group were little higher than those of male antler extract administered group. 5. The levels of serum Ca and P in osteoporosisinduced rats, administered with male or female antler extract, were little higher than those of control group. However, the levels of serum Ca and P in ovariectomized rats were significantly higher than those of control group (p<0.05). 6. After administration of female or male antler extract to osteoporosis-induced rats, the activities of serum ALP increased compared with those of normal control group. There were significant differences between the serum ALP activities of FA 1,250 and 625 groups (p<0.05). These findings suggest a possible protective and therapeutic effects of female or male antler extract against bone loss in ovariectomized rats, associated with a significant increase of serum estradiol level.

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Mesothermal Gold Mineralization in the Boseong-Jangheung area, Chollanamdo-province (전라남도 보성-장흥지역의 중열수 금광화작용)

  • 허철호;윤성택;소칠섭
    • Economic and Environmental Geology
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    • v.35 no.5
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    • pp.379-393
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    • 2002
  • Within the Boseong-Jangheung area of Korea, five hydrothermal gold (-silver) quartz vein deposits occur. They have the characteristic features as follows: the relatively gold-rich nature of e1ectrurns; the absence of Ag-Sb( -As) sulfosalt mineral; the massive and simple mineralogy of veins. They suggest that gold mineralization in this area is correlated with late Jurassic to Early Cretaceous, mesothermal-type gold deposits in Korea. Fluid inclusion data show that fluid inclusions in stage I quartz of the mine area homogenize over a wide temperature range of 200$^{\circ}$ to 460$^{\circ}$C with salinities of 0.0 to 13.8 equiv. wt. % NaCI. The homogenization temperature of fluid inclusions in stage II calcite of the mine area ranges from 150$^{\circ}$ to 254$^{\circ}$C with salinities of 1.2 to 7.9 equiv. wt. % NaCI. This indicates a cooling of the hydrothermal fluid with time towards the waning of hydrothermal activity. Evidence of fluid boiling including CO2 effervescence indicates that pressures during entrapment of auriferous fluids in this area range up to 770 bars. Calculated sulfur isotope composition of auriferous fluids in this mine area (${\delta}^34S$_{{\Sigma}S}$$\textperthousand$) indicates an igneous source of sulfur in auriferous hydrothermal fluids. Within the Sobaegsan Massif, two representative mesothermal-type gold mine areas (Youngdong and Boseong-Jangheung areas) occur. The ${\delta}^34S values of sulfide minerals from Youngdong area range from -6.6 to 2.3$\textperthousand$ (average=-1.4$\textperthousand$, N=66), and those from BoseongJangheung area range from -0.7 to 3.6$\textperthousand$ (average=1.6$\textperthousand$, N=39). These i)34S values of both areas are comparatively lower than those of most Korean metallic ore deposits (3 to 7TEX>$\textperthousand$). And, within the Sobaegsan Massif, the ${\delta}^34S values of Youngdong area are lower than those of Boseong-Jangheung area. It is inferred that the difference of ${\delta}^34S values within the Sobaegsan Massif can be caused by either of the following mechanisms: (1) the presence of at least two distinct reservoirs (both igneous, with ${\delta}^34S values of < -6 $\textperthousand$ and 2$\pm$2 %0) for Jurassic mesothermal-type gold deposits in both areas; (2) different degrees of the mixing (assimilation) of 32S-enriched sulfur (possibly sulfur in Precambrian pelitic basement rocks) during the generation and/or subsequent ascent of magma; and/or (3) different degrees of the oxidation of an H2S-rich, magmatically derived sulfur source ${\delta}^34S = 2$\pm$2$\textperthousand$) during the ascent to mineralization sites. According to the observed differences in ore mineralogy (especially, iron-bearing ore minerals) and fluid inclusions of quartz from the mesothermal-type deposits in both areas, we conclude that pyrrhotite-rich, mesothermal-type deposits in the Youngdong area formed from higher temperatures and more reducing fluids than did pyrite(-arsenopyrite)-rich mesothermal-type deposits in the Boseong-Jangheung area. Therefore, we prefer the third mechanism than others because the ${\delta}^34S values of the Precambrian gneisses and Paleozoic sedimentary rocks occurring in both areas were not known to the present. In future, in order to elucidate the provenance of ore sulfur more systematically, we need to determine ${\delta}^34S values of the Precambrian metamorphic rocks and Paleozoic sedimentary rocks consisting the basement of the Korean Peninsula including the Sobaegsan Massif.

The Ripening of Camembert Cheese Made with Mucor Miehei Rennet (Mucor Miehei 응유효소(凝乳酵素)로 제조(製造)한 Camembert Cheese의 숙성(熟成)에 관(關)한 연구(硏究))

  • Park, Mooh Il;Kim, Jong Woo
    • Korean Journal of Agricultural Science
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    • v.16 no.2
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    • pp.179-200
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    • 1989
  • Mucor miehei rennet(MR) was added as calf rennet(CR) substitutes in the fixed amounts of mixed rennets in making Camembert cheese. The conditions in the variations of chemical composition: water-soluble nitrogen, non-caseinic nitrogen, non-proteinic nitrogen, amino nitrogen, ammoniacal nitorgen, electrophoresis, molecular fractionation, mineral distribution, texture characterisitics, free amino acids and free fatty acids, were checked up with the sensory test and the chesse yields at each ripening period. The results obtained by investigating the utility of Mucor rennet were summarized as follows: 1. CR chesse, MR cheese and the mixed-rennet chesse failed to show any significant difference in their yields of 15%. 2. The contents of protein, fat and ash in MR cheese gave lower value than CR cheese did and with progress of ripening lactose decreased rapidly after 14 days of ripening. The difference among the rate of addition of mucor rennet was not recognized. 3. The WSN contents of 5 fresh sample chesse were from 14.7% to 17.3% and WSN increased from 39.7% to 41.0% with progress of ripening. After 21 days of ripening MR chesse had more WSN than CR cheese did. In NCN and ammoniacal nitrogen MR cheese showed higher value. 4. As the ripening progressed, MR chesse showed more cystein, phenylalanine and proline than CR chesse did but it failed to show any increase in aspartic acid, threonine and glutamic acid etc. 5. In the content of free fatty acid MR chesse showed higher value than CR cheese did and with the progress of ripening fatty acids increased from 8.36 mEq to 26.36 mEq but did not show any significant difference in the cheese types by the coagulant ratio. 6. Ca contents in the sample chesse were 0.238-0.27%, Mg 0.019-0.022%, Na 0.910-1.047%, and K 0.175-0.200%. The important non-sedimentable Ca in casein remained from 61 % to 77% without regard the ripening periods and added-rennets and Mg remained from 59.1% to 92.5% in non-sedimentable and water-soluble conditions. 7. In the fractionation of protein by ultrafilteration, MW> $5{\times}10^4$ decresed from 95% at the beginning period of ripening to 45% and MW< $10^4$ increased from 0.2% to 38% and definite caseinolysis was shown in all samples. 8. All the cheese showed to different electrophoretic patterns for the added-amounts of mucor rennet in the 14 days of ripenig. In the 28 days or ripening, MR cheese kept some bands on the patterns compared with CR cheese. 9. In vitro digestibility increased from 81.48-94.81 % to 94.47-98.61% but failed to show any significant difference in the cheese types by the coagulant ratio. 10. In hardness, MR cheese showed lower value compared with CR cheese as the ripening progressed. 11. The results of the sensory test failed to show any difference in flora rind, feelings in mouth and hands, deep structure, flavor and bitterness between CR Camembert cheese and MR Camembert chesse.

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Studies on the Constituents of Gynostemma pentaphyllum Makino (덩굴차(Gynostemma pentaphylum Makino)의 성분에 관한 연구)

  • Lee, Heon-Ok;Ko, Young-Su
    • Korean journal of food and cookery science
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    • v.6 no.4
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    • pp.69-83
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    • 1990
  • Gynostemma pentaphyllum Makino is a kind of perennial liana plant belonging to the Cucurbitaceae family. Since it was first discovered and reported to the Japanese academy in 1977, it came to be widely known to China and Southeast Asia areas as well as Japan. In Korea its name began to appear in the first half of 1980's, and it is now being nationwidely cultivated and popularized as tea stuffs. Gynostemma pentaphyllum Makino has remarkably strong propagation power. In addition. since it contains a great quantity of beneficial components, especially saponin it is believed to have excellent medical effects, too. This study was undertaken to examine the value of Gynostemma pentaphyllum Makino as a health-promotint tea, by investigating the components creating the flaver of tea and the saponin ingredient making medical effects as well as by inspecting whether Gynostemma pentaphyllum Makino products show different component arrangements according to their growing districts. As raw materials of the experiment, three kinds of Gynostemma pentaphyllum Makino samples produced in Suwon, Geochang and Uleungdo were taken. To accomplish the formerly stated goals, the contained quantity of the proximate composition, free sugar, reducing sugar, free amino acid, minerals, tannin, caffeine and vitamin C were measured respectively and compared between the samples, while the saponin content was compared with heat extracted from panax ginseng. The results of the experiment are as follows: 1. In the case of the proximate composition, the crude fat content was the highest in the Gymostemma pentaphyllum Makino material from Geochang (1.62%), the second in that from Suwon (1.56%), and the lowest in that from Uleungdo (1.0%). In addition the Geochang: produced sample had the greatest quantity of the crude protein and ash contents: the order of the crude Protein content was the Geochang produced (17.83%), the Suwon-produced (15.87%), and the Uleungdo-produced(12.28%), while that of the ash content was the Geochang-produced (14.80%), the Uleungdo-produced(10.17%), and the Suwon-produced(9.34%). 2. As for the reducing sugar contents, the Suwon-produced scored the highest of the three (3.3%), while the Geochang-produced was 1.3% and the Uleungdo-produced 0.5%. The total content of free sugar was 1.07% (the Suwon-produced), and 0.49% (the Geochang-produced) respectively but the sample from Uleungdo showed almost no free sugar content. The contained quantity of fructose and glucose was the highest among the kinds of free sugar both in the Suwon-produced and in the Geochang-produced. 3. The content of amino acid was the highest in the Suwon-produced(1.41%), the second in the Geochang-produced(1.37%), and the lowest in the Uleungdo-produced(0.53%). In the experiment, sixteen kinds of amino acid were extracted-Asp. Thr. Ser. Glu. Gly. Ala. Val. Het. Ileu. Leu. Tyr. Phe. Lys. His. Arg. Try. All of them except glutamic acid and methionine showed the highest quantity score in the Suwon-produced, while the glutamic acid content was the higest in the Uleungdo-produced and the methionine content in the Geochang-produced. The sequential arrangement of the sixteen contents according to their magnitude ranged from glycine, aspartic acid, and glutamic acid (the highest) to tryptophan, serine and lysine (the lowest). 4. Ten kinds of mineral were detected-Ca, Mn, Cd, K, Na, Pb, Mg, Fe, Zn, Cu. Among them, the content of Cd, Na, Mg, Zn and Fe was the highest in the Geochang-produced and that of K in the Suwon-produced. 5. The Geochang-produced materials contained much a larger quantity of tannin (6.3%) than the Suwon-produced (2.6%). Neither caffeine nor vitamin C was detected in the three kinds of materials. 6. In the case of the saponin content the Geochang-produced showd 2.39%, the Uleungdo-produced 1.77% and the Suwon-produced 1.49% respectively. However, it was found also that the saponin content of Gymostemma pentaphyllum Makino was the same kind as that of panax ginseng.

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Mineralogy and Geochemistry of the Jeonheung and Oksan Pb-Zn-Cu Deposits, Euiseong Area (의성(義城)지역 전흥(田興) 및 옥산(玉山) 열수(熱水) 연(鉛)-아연(亞鉛)-동(銅) 광상(鑛床)에 관한 광물학적(鑛物學的)·지화학적(地化學的) 연구(硏究))

  • Choi, Seon-Gyu;Lee, Jae-Ho;Yun, Seong-Taek;So, Chil-Sup
    • Economic and Environmental Geology
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    • v.25 no.4
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    • pp.417-433
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    • 1992
  • Lead-zinc-copper deposits of the Jeonheung and the Oksan mines around Euiseong area occur as hydrothermal quartz and calcite veins that crosscut Cretaceous sedimentary rocks of the Gyeongsang Basin. The mineralization occurred in three distinct stages (I, II, and III): (I) quartz-sulfides-sulfosalts-hematite mineralization stage; (II) barren quartz-fluorite stage; and (III) barren calcite stage. Stage I ore minerals comprise pyrite, chalcopyrite, sphalerite, galena and Pb-Ag-Bi-Sb sulfosalts. Mineralogies of the two mines are different, and arsenopyrite, pyrrhotite, tetrahedrite and iron-rich (up to 21 mole % FeS) sphalerite are restricted to the Oksan mine. A K-Ar radiometric dating for sericite indicates that the Pb-Zn-Cu deposits of the Euiseong area were formed during late Cretaceous age ($62.3{\pm}2.8Ma$), likely associated with a subvolcanic activity related to the volcanic complex in the nearby Geumseongsan Caldera and the ubiquitous felsite dykes. Stage I mineralization occurred at temperatures between > $380^{\circ}C$ and $240^{\circ}C$ from fluids with salinities between 6.3 and 0.7 equiv. wt. % NaCl. The chalcopyrite deposition occurred mostly at higher temperatures of > $300^{\circ}C$. Fluid inclusion data indicate that the Pb-Zn-Cu ore mineralization resulted from a complex history of boiling, cooling and dilution of ore fluids. The mineralization at Jeonheung resulted mainly from cooling and dilution by an influx of cooler meteoric waters, whereas the mineralization at Oksan was largely due to fluid boiling. Evidence of fluid boiling suggests that pressures decreased from about 210 bars to 80 bars. This corresponds to a depth of about 900 m in a hydrothermal system that changed from lithostatic (closed) toward hydrostatic (open) conditions. Sulfur isotope compositions of sulfide minerals (${\delta}^{34}S=2.9{\sim}9.6$ per mil) indicate that the ${\delta}^{34}S_{{\Sigma}S}$ value of ore fluids was ${\approx}8.6$ per mil. This ${\delta}^{34}S_{{\Sigma}S}$ value is likely consistent with an igneous sulfur mixed with sulfates (?) in surrounding sedimentary rocks. Measured and calculated hydrogen and oxygen isotope values of ore-forming fluids suggest meteoric water dominance, approaching unexchanged meteoric water values. Equilibrium thermodynamic interpretation indicates that the temperature versus $fs_2$ variation of stage I ore fluids differed between the two mines as follows: the $fs_2$ of ore fluids at Jeonheung changed with decreasing temperature constantly near the pyrite-hematite-magnetite sulfidation curve, whereas those at Oksan changed from the pyrite-pyrrhotite sulfidation state towards the pyrite-hematite-magnetite state. The shift in minerals precipitated during stage I also reflects a concomitant $fo_2$ increase, probably due to mixing of ore fluids with cooler, more oxidizing meteoric waters. Thermodynamic consideration of copper solubility suggests that the ore-forming fluids cooled through boiling at Oksan and mixing with less-evolved meteoric waters at Jeonheung, and that this cooling was the main cause of copper deposition through destabilization of copper chloride complexes.

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Paleomagnetism, Stratigraphy and Geologic Structure of the Tertiary Pohang and Changgi Basins; K-Ar Ages for the Volcanic Rocks (포항(浦項) 및 장기분지(盆地)에 대한 고지자기(古地磁氣), 층서(層序) 및 구조연구(構造硏究); 화산암류(火山岩類)의 K-Ar 연대(年代))

  • Lee, Hyun Koo;Moon, Hi-Soo;Min, Kyung Duck;Kim, In-Soo;Yun, Hyesu;Itaya, Tetsumaru
    • Economic and Environmental Geology
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    • v.25 no.3
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    • pp.337-349
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    • 1992
  • The Tertiary basins in Korea have widely been studied by numerous researchers producing individual results in sedimentology, paleontology, stratigraphy, volcanic petrology and structural geology, but interdisciplinary studies, inter-basin analysis and basin-forming process have not been carried out yet. Major work of this study is to elucidate evidences obtained from different parts of a basin as well as different Tertiary basins (Pohang, Changgi, Eoil, Haseo and Ulsan basins) in order to build up the correlation between the basins, and an overall picture of the basin architecture and evolution in Korea. According to the paleontologic evidences the geologic age of the Pohang marine basin is dated to be late Lower Miocence to Middle Miocene, whereas other non-marine basins are older as being either Early Miocene or Oligocene(Lee, 1975, 1978: Bong, 1984: Chun, 1982: Choi et al., 1984: Yun et al., 1990: Yoon, 1982). However, detailed ages of the Tertiary sediments, and their correlations in a basin and between basins are still controversial, since the basins are separated from each other, sedimentary sequence is disturbed and intruded by voncanic rocks, and non-marine sediments are not fossiliferous to be correlated. Therefore, in this work radiometric, magnetostratigraphic, and biostratigraphic data was integrated for the refinement of chronostratigraphy and synopsis of stratigraphy of Tertiary basins of Korea. A total of 21 samples including 10 basaltic, 2 porphyritic, and 9 andesitic rocks from 4 basins were collected for the K-Ar dating of whole rock method. The obtained age can be grouped as follows: $14.8{\pm}0.4{\sim}15.2{\pm}0.4Ma$, $19.9{\pm}0.5{\sim}22.1{\pm}0.7Ma$, $18.0{\pm}1.1{\sim}20.4+0.5Ma$, and $14.6{\pm}0.7{\sim}21.1{\pm}0.5Ma$. Stratigraphically they mostly fall into the range of Lower Miocene to Mid Miocene. The oldest volcanic rock recorded is a basalt (911213-6) with the age of $22.05{\pm}0.67Ma$ near Sangjeong-ri in the Changgi (or Janggi) basin and presumed to be formed in the Early Miocene, when Changgi Conglomerate began to deposit. The youngest one (911214-9) is a basalt of $14.64{\pm}0.66Ma$ in the Haseo basin. This means the intrusive and extrusive rocks are not a product of sudden voncanic activity of short duration as previously accepted but of successive processes lasting relatively long period of 8 or 9 Ma. The radiometric age of the volcanic rocks is not randomly distributed but varies systematically with basins and localities. It becomes generlly younger to the south, namely from the Changgi basin to the Haseo basin. The rocks in the Changgi basin are dated to be from $19.92{\pm}0.47$ to $22.05{\pm}0.67Ma$. With exception of only one locality in the Geumgwangdong they all formed before 20 Ma B.P. The Eoil basalt by Tateiwa in the Eoil basin are dated to be from $20.44{\pm}0.47$ to $18.35{\pm}0.62Ma$ and they are younger than those in the Changgi basin by 2~4 Ma. Specifically, basaltic rocks in the sedimentary and voncanic sequences of the Eoil basin can be well compared to the sequence of associated sedimentary rocks. Generally they become younger to the stratigraphically upper part. Among the basin, the Haseo basin is characterized by the youngest volcanic rocks. The basalt (911214-7) which crops out in Jeongja-ri, Gangdong-myon, Ulsan-gun is $16.22{\pm}0.75Ma$ and the other one (911214-9) in coastal area, Jujon-dong, Ulsan is $14.64{\pm}0.66Ma$ old. The radiometric data are positively collaborated with the results of paleomagnetic study, pull-apart basin model and East Sea spreading theory. Especially, the successively changing age of Eoil basalts are in accordance with successively changing degree of rotation. In detail, following results are discussed. Firstly, the porphyritic rocks previously known as Cretaceous basement (911213-2, 911214-1) show the age of $43.73{\pm}1.05$$49.58{\pm}1.13Ma$(Eocene) confirms the results of Jin et al. (1988). This means sequential volcanic activity from Cretaceous up to Lower Tertiary. Secondly, intrusive andesitic rocks in the Pohang basin, which are dated to be $21.8{\pm}2.8Ma$ (Jin et al., 1988) are found out to be 15 Ma old in coincindence with the age of host strata of 16.5 Ma. Thirdly, The Quaternary basalt (911213-5 and 911213-6) of Tateiwa(1924) is not homogeneous regarding formation age and petrological characteristics. The basalt in the Changgi basin show the age of $19.92{\pm}0.47$ and $22.05{\pm}0.67$ (Miocene). The basalt (911213-8) in Sangjond-ri, which intruded Nultaeri Trachytic Tuff is dated to be $20.55{\pm}0.50Ma$, which means Changgi Group is older than this age. The Yeonil Basalt, which Tateiwa described as Quaternary one shows different age ranging from Lower Miocene to Upper Miocene(cf. Jin et al., 1988: sample no. 93-33: $10.20{\pm}0.30Ma$). Therefore, the Yeonil Quarterary basalt should be revised and divided into different geologic epochs. Fourthly, Yeonil basalt of Tateiwa (1926) in the Eoil basin is correlated to the Yeonil basalt in the Changgi basin. Yoon (1989) intergrated both basalts as Eoil basaltic andesitic volcanic rocks or Eoil basalt (Yoon et al., 1991), and placed uppermost unit of the Changgi Group. As mentioned above the so-called Quarternary basalt in the Eoil basin are not extruded or intruaed simultaneously, but differentiatedly (14 Ma~25 Ma) so that they can not be classified as one unit. Fifthly, the Yongdong-ri formation of the Pomgogri Group is intruded by the Eoil basalt (911214-3) of 18.35~0.62 Ma age. Therefore, the deposition of the Pomgogri Group is completed before this age. Referring petrological characteristics, occurences, paleomagnetic data, and relationship to other Eoil basalts, it is most provable that this basalt is younger than two others. That means the Pomgogri Group is underlain by the Changgi Group. Sixthly, mineral composition of the basalts and andesitic rocks from the 4 basins show different ground mass and phenocryst. In volcanic rocks in the Pohang basin, phenocrysts are pyroxene and a small amount of biotite. Those of the Changgi basin is predominant by Labradorite, in the Eoil by bytownite-anorthite and a small amount pyroxene.

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A Study on Nutritive Values and Salt Contents of Commercially Prepared Take-Out Boxed-Lunch In Korea (한국형 시판 도시락의 영양가 및 식염함량)

  • Kim, Bok-Hee;Lee, Eun-Wha;Kim, Won-Kyung;Lee, Yoon-Na;Kwak, Chung-Shil;Mo, Sumi
    • Journal of Nutrition and Health
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    • v.24 no.3
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    • pp.230-242
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    • 1991
  • This research was conducted on the 10 take-out boxed-lunches commercially prepared in the department stores. chain stores. and the public railroad trains in Korea. Sampling was conducted from February 1990 to March 1990. Nutritive values and sodium contents of the 10 boxed-lunch samples are summarized as follows : 1) The average weight(percentage) of the cooked rice and the side dishes were 304.6g(49.4) and 312.4(506%), respectively. The weight of these samples were significantly heavier than that of Japanese style boxed-lunches. 2) The average number of the side dishes was 12. The average numbers of food items classified by the five food groups were 6.1 in protein food group, 0.3 in calcium food group. 6.0 in vitamin and mineral food group. 1.5 in carbohydrate food group, and 1.5 in oil and fat food group. 3) They contained on the average 840.7kcal of energy, 38.9g of protein, 22.7g of fat, 120.4g of carbohydrate. 300.8mg of calcium. 410.8mg of phosphours, 6.61 mg of iron. 219.8 R.E. of vitamin A, 0.46mg of thiamin, 0.67mg of riboflavin, 10.5mg of niacin, 27.5mg of ascorbic acid. Thus. except vitamin t the content of all the nutrients were higher than the value of 1/3 of the RDA for adults. 4) The high priced group(group 2) had more protein, calcuim. iron and niacin contents than the cheaper group(group 1). Probably, it's because the group 2 had more animal foods than the group 1. 5) The average energy content per unit price(100 won) was 37.3kcal and the average protein content per unit price(100 won) was 1.64g. Korena style boxed-lunches had higher energy and protein contents per unit price than Japanese style, and the group 1 higher than the group 2. 6) The average energy Proportions of Protein, carbohydrate. and fat were 18.3%, 57.4%, and 24.3%, respectively. These proportions are good enough. 7) Frequency of cooking methods for the side dishes were found in the decreasing order : pan-frying, frying, braising, seasoning, kimchi, grilling, pickling, stir-frying, steaming and fermenting. Generally simple cooking methods were used, thus the menus were lack or varieties. 8) Frequency of colors for the side dishes were found in the decreasing order : red, brown. yellow, green, black, white. Too much red pepper was used. 9) The average capacity of the containers for the staples and the side dishes were 468.1ml and 590.6ml, respectively. And the containers could not keep the food items well seperated. 10) The average contensts of sodium and salt were 2.287mg and 5.76g, in the range of 1, 398mg to 3, 489mg and 3.53g to 8.80g, respectively. These are much higher values than the recommended amount of salt.

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