• Title/Summary/Keyword: Mineral grade

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A checklist of vascular plants in limestone areas on the Korean Peninsula (한반도 석회암지대의 관속식물 목록)

  • KIM, Jung-Hyun;NAM, Gi-Heum;LEE, Seung-bae;SHIN, Sookyung;KIM, Jin-Seok
    • Korean Journal of Plant Taxonomy
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    • v.51 no.3
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    • pp.250-293
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    • 2021
  • Limestone areas are sedimentary rock outcrops consisting of calcium carbonate created several hundreds of millions of years ago by calcium-secreting marine organisms and subsequently lifted above sea level by tectonic movement. Limestone areas support very high levels of endemic species of plants and are recognized as biodiversity areas with much biological information. The purpose of this study is to devise a strategy for the comprehensive conservation of the vegetation of limestone areas through analyses of the floristics and plant species compositions in ten limestone areas on the Korean Peninsula. The results of 153 field surveys from April of 2010 to October of 2016 identified 1,202 taxa in total, representing 1,096 species, 18 subspecies, 84 varieties, 2 forms, and 2 hybrids in 530 genera and 133 families. Among them, 55 taxa were endemic plants to Korea, and 38 taxa were red data plants. The floristic target plants amounted to 102 taxa, specifically 27 taxa of grade V and 75 taxa of grade IV. In all, 121 alien plants were recorded in the investigated area. Calciphilous plants amounted to 102 taxa, specifically 14 taxa of calciphilous indicator plants, 30 taxa of superlative most calciphilous plants, and 58 taxa of comparative more calciphilous plants. A cluster analysis showed a high degree of similarity between sites that are geographically adjacent with similar habitat environments. Limestone areas also supported groups distinct from those in non-limestone areas, demonstrating the specificity of limestone flora. Plant geography approaches therefore appear to be crucial to gain a better understanding of the level of biodiversity in limestone areas, not only at the interspecific but also at the intraspecific level. These results highlight the importance of protecting limestone habitats to preserve not only their interspecific but also the intraspecific diversity, which is highly threatened.

Occurrence and Chemical Composition of Ti-bearing Minerals from Drilling Core (No.04-1) at Gubong Au-Ag Deposit Area, Republic of Korea (구봉 금-은 광상일대 시추코아(04-1)에서 산출되는 함 티타늄 광물들의 산상과 화학조성)

  • Bong Chul Yoo
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.3
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    • pp.185-197
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    • 2023
  • The Gubong Au-Ag deposit consists of eight lens-shaped quartz veins. These veins have filled fractures along fault zones within Precambrian metasedimentary rock. This has been one of the largest deposits in Korea, and is geologically a mix of orogenic-type and intrusion-related types. Korea Mining Promotion Corporation drilled into a quartz vein (referred to as the No. 6 vein) with a width of 0.9 m and a grade of 27.9 g/t Au at a depth of -728 ML by drilling (No. 90-12) in the southern site of the deposit, To further investigate the potential redevelopment of the No. 6 vein, another drilling (No. 04-1) was carried out in 2004. In 2004, samples (wallrock, wallrock alteration and quartz vein) were collected from the No. 04-1 drilling core site to study the occurrence and chemical composition of Ti-bearing minerals (ilmenite, rutile). Rutile from mineralized zone at a depth of -275 ML occur minerals including K-feldspar, biotite, quartz, calcite, chlorite, pyrite in wallrock alteration zone. Ilmenite and rutile from ore vein (No. 6 vein) at a depth of -779 ML occur minerals including white mica, chlorite, apatite, zircon, quartz, calcite, pyrrhotite, pyrite in wallrock alteration zone and quartz vein. Based on mineral assemblage, rutile was formed by hydrothermal alteration (chloritization) of Ti-rich biotite in the wallrock. Chemical composition of ilmenite has maximum values of 0.09 wt.% (HfO2), 0.39 wt.% (V2O3) and 0.54 wt.% (BaO). Comparing the chemical composition of rutile at a depth -275 ML and -779 ML, Rutile at a depth of -779 ML is higher contents (WO3, FeO and BaO) than rutile at a depth of -275 ML. The substitutions of rutile at a depth of -275 ML and -779 ML are as followed : rutile at a depth of -275 ML Ba2+ + Al3+ + Hf4+ + (Nb5+, Ta5+) ↔ 3Ti4+ + Fe2+, 2V4+ + (W5+, Ta5+, Nb5+) ↔ 2Ti4+ + Al3+ + (Fe2+, Ba2+), Al3+ + V4++ (Nb5+, Ta5+) ↔ 2Ti4+ + 2Fe2+, rutile at a depth of -779 ML 2 (Fe2+, Ba2+) + Al3+ + (W5+, Nb5+, Ta5+) ↔ 2Ti4+ + (V4+, Hf4+), Fe2+ + Al3+ + Hf 4+ + (W5+, Nb5+, Ta5+) ↔ 2Ti4+ + V4+ + Ba2+, respectively. Based on these data and chemical composition of rutiles from orogenic-type deposits, rutiles from Gubong deposit was formed in a relatively oxidizing environment than the rutile from orogenictype deposits (Unsan deposit, Kori Kollo deposit, Big Bell deposit, Meguma gold-bearing quartz vein).

Mineral Nutrition of Field-Grown Rice Plant -II Recovery of fertilizer nitrogen, phosphorus, and potassium in relation to climatic zone and physical or chemical characteristics of soil profile (포장재배(圃場栽培) 수도(水稻)의 무기영양(無機營養) -II 삼요소(三要素) 이용율(利用率)과 기상권(氣象圈) 및 토양단면(土壤斷面)의 물리(物理)·화학적(化學的) 성질(性質)과의 관계(關係))

  • Park, Hoon;Shin, Chun Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.1
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    • pp.17-26
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    • 1973
  • A survey on nutrient recovery by rice plant was carried out countrywide in 1967 and 1968. The relationships between percent recovery of fertilizer nutrient and climatic zone or deposition mode, drainage grade, and texture of paddy soil profile, or chemical characteristics of surface soil were as follows. 1. The percent recovery of fertilizer nitrogen was highest in south and least in north, and that of potassium was highest in south and least in middle climatic zone. 2. Since the percent recovery of Phosphorus variates yearly with climatic zone, mode of deposition drainage grade or soil texture, it seemed to depend greatly on soil-weather interaction. 3. Nitrogen recovery was highest in alluvial colluvial (AC) and it was followed by alluvial (A), fluvomarine (FM) and old alluvial in decreasing order while potassium recovery was OA>AC>A>FM. 4. The greater the drainage was, the higher the nitrogen recovery. The recovery of potassium and phosphorus tended to show high in moderately well drain, and low in poorly and well drain. 5. Nitrogen recovery was highest in fine silty and gradually decreased with coarseness. That of potassium or phosphorus was greater in those below fine loamy than in those above coarse silty. 6. Nitrogen recovery was high in Jisan, Geugrag, and Sindab series, and low in Hwadong, Gyuam, Yongji and Hwabong series. 7. Nitrogen recovery showed significant positive correlation with the content of organic matter (OM), Ca, CEC of surface soil and only in the year of high phosphorus recovery it had significant negative correlation with soil phosphorus. Phosphorus recovery had significant posititive correlation with CEC, Mg or Ca. 8. Potassium recovery showed negative correlation with K/(Ca+Mg), P, OM or K while positive correlation with Ca, Mg, CEC but significant only with K/(Ca+Mg) in the year of low potassium recovery. In the year of high K recovery it showed positive correlation with P, OM, K/(Ca+Mg) or K while negative with CEC, Mg or Ca but significant only with P, OM or CEC. Soil potassium has significant positive correlation with soil OM and P only in the year of low potassium recovery. 9. The percent recovery of N, P or K showed negative correlation coefficient with pH without significant. 10. There was significant positive correlation between OM and P, K or K/(Ca+Mg), P and K or K/(Ca+Mg), K and K/(Ca+Mg), Mg or CEC, Ca and K/(Ca+Mg), Mg, CEC or pH, Mg and CEC while significant negative correlation between Mg and OM, P or K/(Ca+Mg), P and CEC, Ca and K/(Ca+Mg). 11. From the percent rcovery of fertilizer and soil chemical characteristics it was known that soil organic matter increase nitrogen uptake, that K uptake has closer relation to K/(Ca+Mg) than K, that Mg affects P ugtake, and that the annual difference of P and K recovery was partly explainable.

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Study of Utilization of Natural Zeolites as Functional Materials for Water Purification (II): Adsorption Properties of Heavy Metal Ions by Domestic Zeolites (천연 제올라이트의 수환경 개선용 기능성 소재로의 활용에 관한 연구 (II): 국내산 제올라이트의 중금속 이온 흡착 특성)

    • Journal of the Mineralogical Society of Korea
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    • v.16 no.3
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    • pp.201-213
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    • 2003
  • The adsorption property and ability of domestic zeolites for some heavy metal ions (Ag, Pb, Cr, Cu, Zn, Mn), which may cause a serious environmental problem in industrial wastewater, were evaluated on ore unit through a series of adsorption experiments together with careful examinations of mineral composition and properties of the zeolites. Though the adsorption behavior basically took place in the form of a cation exchange reaction, the higher CEC value does not necessarily to imply the higher adsorption capacity for a specific heavy metal. A general trend of the adsorption selectivity for heavy metals in the zeolites is determined to be as follow: $Ag\geq$Pb>Cr,Cu$\geq$Zn>Mn, but the adsorption properties of heavy metal ions somewhat depend on the species and composition of zeolite. Clinoptilolite tends to adsorb selectively Cu in case of Cr and Cu, whereas heulandite prefers Cr to Cu. A dominant adsorption selectivity of the zeolite ores for Ag and Pb is generally conspicuous regardless of their zeolite species and composition. The zeolite ores exhibit a preferential adsorption especially for $Ag^{+}$ so as not to regenerate when treated with $Na^{+}$ . In the adsorption capacity for heavy meta ions, the zeolites differ in great depending on their species: ferrierite>clinoptilolite>heulandite. Considering the CEC value of mordenite, the mordenite-rich ore appears to be similar to the clinoptilolite ore in the adsorption capacity. The adsorption capacity for heavy metals is not positively proportional to the CEC values of the zeolites measured by the exchange reaction with ammonium ion. In addition, the adsorption capacity roughly tends to depend on the zeolite contents, i.e., the grade of zeolite ore, but the trend is not consistent at all in some ores. These may be caused by the adsorption selectivity for some specific heavy metals, the presence of possible stacking micro-faults and natural cations such as K hardly to exchange in the zeolite. Considering the economic availability and functional effectiveness as natural zeolite resources, clinoptilolite ores could be applicable to utilize the domestic zeolites for the removal of heavy metals.

Quality Analysis of Diverse Rice Species for Rice Products (쌀 가공제품을 위한 다양한 쌀의 품질분석)

  • Kim, Hye-Ryun;Kwon, Young-Hee;Kim, Jae-Ho;Ahn, Byung-Hak
    • Korean Journal of Food Science and Technology
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    • v.43 no.2
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    • pp.142-148
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    • 2011
  • The objective of this study was to analyze proximate composition and physicochemical properties according to different kinds of rice. In total, 20 varieties of rice were used (Domestic-19, Imported-1). The moisture contents ranged from $11.11{\pm}0.20$ to $3.28{\pm}0.03%$. The crude protein and crude lipid contents were ranged from $5.04{\pm}0.03$ to $7.02{\pm}0.10%$ and $0.18{\pm}0.01$ to $0.73{\pm}0.05%$, respectively. The mineral contents were Calcium, $3.56{\pm}0.11-6.69{\pm}0.08mg/100g$; Sodium, $3.39{\pm}0.01-17.43{\pm}0.04mg/100g$; Phosphorus, $64.12{\pm}0.88-102.0{\pm}0.36mg/100g$; Zinc, $0.95{\pm}0.01-1.75{\pm}0.0mg/100g$; Iron, $0.19{\pm}0.0-0.69{\pm}0.02g/100g$; Magnesium, $9.89{\pm}0.47-23.31{\pm}0.21mg/100g$; Potassium, $47.11{\pm}3.49-82.19{\pm}1.08mg/100g$;and Manganese, $0.47{\pm}0.0-1.14{\pm}0.01mg/100g$. Eighteen kinds of rice exhibited small kernels. Amylose contents ranged from $10.3{\pm}1.27$ to $19.4{\pm}0.15%$, while starch value ranged from $70.8{\pm}2.67$ to $80.1{\pm}5.09%$. Alkali digestion value was described as 5-6 grade and gel consistency was shown to be 'soft' regardless of the rice kinds.

Petrochemistry and Environmental Geochemistry of Shale and Coal from the Daedong Supergroup, Chungnam Coal Field, Korea (충남탄전, 대동누층군의 셰일과 탄질암에 관한 암석화학 및 환경지구화학적 특성)

  • Lee, Chan Hee;Lee, Hyun Koo;Kim, Kyoung-Woong
    • Economic and Environmental Geology
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    • v.30 no.5
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    • pp.417-431
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    • 1997
  • Characteristics of sedimentary rocks and enrichment of toxic elements in shale and coal from the Chungnam coal field were investigated based upon geochemistry of major, trace and rare earth elements. Shale and coal of the area are interbedded along the Traissic to the Jurassic Daedong Supergroup, which can be subdivided into grey shale, black shale and coal. The coal had been mined, however all the mines are abandonded due to the economic problems. The shale and coal are characterized by relatively low contents of $SiO_2$, and $Al_2O_3$ and high levels of loss-on-ignition (LOI), CaO and $Na_2O$ in comparison with the North American Shale Composite (NASC). Light rare earth elements (La, Ce, Yb and Lu) are highly enriched with the coal. Ratios of $Al_2O_3/Na_2O$ and $K_2O/Na_2O$ in shale and coal range from 30.0 to 351.8 and from 4.2 to 106.8, which have partly negative correlations against $SiO_2/Al_2O_3$ (1.24 to 6.06), respectively. Those are suggested that controls of mineral compositions in shale and coal can be due to substitution and migration of those elements by diagenesis and metamorphism. Shale and coal of the area may be deposited in terrestrial basin deduced from high C/S (39 to 895) and variable composition of organic carbon (0.39 to 18.40 wt.%) and low contents of reduced sulfur (0.01 to 0.05 wt.%). These shale and coal were originated from the high grade metamorphic and/or igneous rocks, and the rare earth elements of those rocks are slightly influenced with diagenesis and metamorphism on the basis of $Al_2O_3$ versus La, La against Ce, Zr versus Yb, the ratios of La/Ce (0.38 to 0.85) and Th/U (3.6 to 14.6). Characteristics of trace and rare earth elements as Co/Th (0.07 to 0.86), La/Sc (0.31 to 11.05), Se/Th (0.28 to 1.06), V/Ni (1.14 to 3.97), Cr/V (1.4 to 28.3), Ni/Co (2.12 to 8.00) and Zr/Hf (22.6~45.1) in the shale and coal argue for inefficient mixing of the simple source lithologies during sedimentation. These rocks also show much variation in $La_N/Yb_N$ (1.36 to 21.68), Th/Yb (3.5 to 20.0) and La/Th (0.31 to 7.89), and their origin is explained by derivation from a mixture of mainly acidic igneous and metamorphic rocks. Average concentrations in the shale and coal are As=7.2 and 7.5, Ba=913 and 974, Cr=500 and 145, Cu=20 and 26, Ni=38 and 35, Pb=30 and 36, and Zn=77 and 92 ppm, respectively, which are similar to those in the NASC. Average enrichment indices for major elements in the shale (0.79) and coal (0.77) are lower than those in the NASC. In addition, average enrichment index for rare earth elements in coal (2.39) is enriched rather than the shale (1.55). On the basis of the NASC, concentrations of minor and/or environmental toxic elements in the shale and coal were depleted of all the elements examined, excepting Cr, Pb, Rb and Th. Average enrichment indices of trace and/or potentially toxic elements (As, Cr, Cu, Ni, Pb, U and Zn) are 1.23 to 1.24 for shale and 1.06 to 1.22 for coal, respectively.

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Time-relationship between Deformation and Growth of Metamorphic Minerals around the Shinbo Mine, Korea: the Relative Mineralization Time of Uranium Mineralized Zone (신보광산 주변지역에서 변성광물의 성장과 변형작용 사이의 상대적인 시간관계: 우라늄 광화대의 상대적인 광화시기)

  • Kang, Ji-Hoon;Lee, Deok-Seon
    • Economic and Environmental Geology
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    • v.45 no.4
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    • pp.385-396
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    • 2012
  • The geochemical high-grade uranium anormal zone has been reported in the Shinbo mine and its eastern areas, Jinan-gun, Jeollabuk-do located in the southwestern part of Ogcheon metamorphic zone, Korea. In this paper is reported the time-relationship between deformation and growth of metamorphic minerals in the eastern area of Shinbo mine, which consists of the Precambrian metasedimentary rocks (quartzite, metapelite, metapsammite) and the age-unknown pegmatite and Cretaceous porphyry which intrude them, and is considered the relative mineralization time on the basis of the previous research's result. The D1 deformation formed the straight-type Si internal foliation which is defined mainly as the arrangement of elongate quartz, biotite, opaque mineral in andalusite porphyroblast. The D2 deformation, which is defined by the microfolding of Si foliation, formed S2 crenulation cleavage. It can be divided into two sub-phases, early crenulation and late crenulation. The former occurs as the curvetype Si foliation in the mantle part of andalusite. The latter occurs as S1-2 composite foliation which warps around the andalusite. The andalusite porphyroblast began to grow under non-deformation condition after the formation of S1 foliation which corresponds to the straight-type Si foliation. It continued to grow before the late crenulation phase. The age-unknown pegmatite intruded after the D2 deformation and grew the fibrous sillimanite which random masks the S1-2 composite foliation. The D3 deformation formed F3 fold which folded the S1-2 composite foliation, D2 crenulation, fibrous sillimanite. It means that the intrusion of pegmatite related to the growth of the fibrous sillimanite took place during the inter-tectonic phase of D2 and D3 deformations. The retrograde metamorphism is recognized by the chloritization of biotite and two-way cleavage lamellae which is parallel to the S1-2 composite foliation and the F3 fold axial surface in the andalusite porphyroblast. It occurred during the D2 late crenulation phase and D3 deformation. In considering of the previous research's result inferring the most likely candidate for the uranium source rock as pegamatite, it indicates that the age-unknown pegmatite intruded during the inter-tectonic phase of D2 and D3 deformations, i.e. during the retrograde metamorphism related to the uplifting of crust, and formed the uranium ore zone around the Shinbo mine.

Metamorphic P-T Paths from Devonian Pelitic Schists from the Pelham Dome, Massachusetts, USA (뉴잉글랜드 펠암돔 주변부 데본기 변성 이질암의 변성 온도-압력 경로)

  • 김형수
    • The Journal of the Petrological Society of Korea
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    • v.9 no.4
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    • pp.211-237
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    • 2000
  • Major element zoning has been analyzed in garnet porphroblasts obtained from the Grt-St and Ky-Grt-St grade assemblages in Zones I on the northern flank of the Pelham Dome, north central Massachusetts. These porphyroblasts grew during multiple phases of deformation and meta-morphism revealed by the inclusion trail geometry plus the chemical zoning patterns within garnet porphyroblasts. Unusual zoning patterns, including zoning reversals and gradient changes in XMn, zlgzag patterns in Fe/(Fe +Mg) and staircase-shaped patterns in XCa, are coincident with textural truncations and other changes in microstructure within the garnet porphrublasts. Chemical variations in plagioclase, biotite, muscovite and staurolite combined with inclusion trail geometry and petrography reveal that the garnet zoning patterns are modified by combinations of the following. (1) Uni-and divariant reactions involving garnet consumption(Grt+ Chl+Ms=St+Bt+Qtz + $H_2$O) and production(St+Ms + Qtz= Bt+ Grt +A1$_2$$SiO_{5}$ + $H_2$O). (2) Deformation induced episudic ionit dissolution, preferential diffusion and re-distribution during foliation development. (3) P-T changes during growth of the porphyroblasts. The P-T paths combined with petrographic and inclusion trail morphology observations consist of two pattens; (1) heating/compression during NW-SE shortening; and (2) decompression with cooling during NNW-SSE shortening. Based on temperature-time(T-t) geochronological data and late-Paleozoic tectonic model, Alleghanian metamorphism, which is the result of heterogeneous shearing concentrated along the boundary between the Abalone Terrane(Pelham dome) and cover rocks(Bronson Hill Terrane), has produced Ky-St-Ms mineral assemblage during Pennsylvanian(290-300 Ma) in Shutesbury area. However, temperature of alleghanian metamorphism was not high enough to form garnet and staurolite in the Northfiled syncline area. Alleghanian metamorphism has affected only the matrix due to heterogeneous shearing in the study area.

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Effect of Dietary Supplementation of Dried-Citrus Pulp and Wheat Bran on Growth and Meat Quality in Horses (건조감귤박 및 소맥피를 급여한 말의 성장과 육질에 미치는 영향)

  • Chae, Hyun-Seok;Kim, Nam-Young;Cho, In-Chul;Cho, Sang-Rae;Cho, Won-Mo;Park, Yong-Sang;Oh, Shin-Ae;Jang, Aera;Seong, Pil-Nam;Ko, Moon-Suck
    • Journal of Animal Science and Technology
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    • v.55 no.3
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    • pp.219-227
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    • 2013
  • This study was conducted to elucidate the characteristics of equine meat traits and to evaluate the utilization of dried-citrus pulp abundantly produced in Jeju Island as feed ingredient in the diet of finished meat horses. Treatment groups consisted of wheat bran (A) and the dried-pellet mixture of citrus pulp (20%) and wheat bran (80%) (B). Feeding of agricultural by-products were 2 times in a day at the level of 1.5% of body weights. Water and dried-grass forage was not restricted. The average daily gain was similar in both groups. Feed conversion of treatment B showed lower level than that of A. Carcass rate of B was relatively lower than that of A, but meat yield grade of B was higher than that of A. For meat color traits, $L^*$ of B was lighter than that of A, and $b^*$ of group B was lower than that of group A. From the analysis of physical characteristics of equine meats, shearing force had decreased in the treatment B but the levels of drip loss and water holding cavity had increased in the treatment B compared to A. The level of crude fat is lower in the treatment B than the treatment A. For the mineral contents, the treatment B showed higher levels of Ca, K, Mg, Cu and Mn than that of A. For the fatty acid contents, the treatment B showed increased levels of stearic acid, oleic acid, eicosenoic acid, and arachidonic acid compared to A. Consequently, these results suggested that dried-citrus pulp might be utilized as replacement material for equine forage. Please rewrite the whole abstract and should include all required information. Before resubmission, please check it again from a native colleague in your group.

Early Proterozoic Moyitic Series in Daqingshan, Inner Mongolia : Their Characteristics and Tectonis, Magmatic and Thermodynamic Model (내몽고 다큉샨내의 초기원생대 모이아이트계열 : 특성과 지구조, 마그마 그리고 열역학적 모델)

  • Lin CAO;Wei JIN
    • The Journal of the Petrological Society of Korea
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    • v.6 no.2
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    • pp.77-85
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    • 1997
  • The Early Proterozoic reworked rock association occurs within the Preacmbrian high grade metamorphic rocks in the area of Daqingshan, Inner Molgolia. In this association, the various large scale ductile deformation belts, form a nappe structure where the foliation steeply dips to north and the lineation ($340^{circ}-30^{\circ}$) plunges at $45^{\circ}55^{\circ}$. This result indicates the subduction/extension with northern part thrusting over the southern part at high angle. The southern subducted microlithon has the characteristics of prograde metamorphism. The northern thrusted microlithon shows the evidence of retrograde metamorphism with decreasing pressure and increasing temperature. The main rock types of Early Proterozoic Moyites are biotite adamellite and syenogranites occurring in the form of small batholiths or stocks and alkali-feldspar granites in veins. The biotite adamellites are progressively contacted with the Archean and Early Proterozoic rocks and contain a great deal of enclaves of metamorphosed rocks, suggesting an anatexis origin. The geochemical characteristics of moyites show the typical features of anatexis granite. At middle to late Early Proterozoic time, the continent-continent collision formed the large scale thrusting and imbrication of Archean basement rocks. According to the mineral assemblage and thermobarometer of Paria et al. (1988) give the following P-T condition : up-faulted block; $700-710^{\circ}C$, 0.72-0.78 Gpa (early stage) and $600^{\circ}C$, 0.44 Gpa (late stage), footwall block; $620^{\circ}C$, 0.8 Gpa (early stage), $620-840^{\circ}C$, 0.64-0.45 Gpa (peak) and $620-630^{\circ}C$, 0.35Gpa (late stage). These results suggest a clockwise P-T-t path (jin et al., 1991, 1994). According to the depth-temperature model in the comperature subduction zone and the experimental data of Wyllie et al. (1983), we propose a tectonic-magmatic-thermal model to account for metamorphism-anatexis of moyite occurring in subduction-shear zone.

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