• Title/Summary/Keyword: thermogenic gas

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Gas Hydrate Systems at Hydrate Ridge;Results from ODP Leg 204

  • Lee, Young-Joo;Kim, Ji-Hoon;Ryu, Byong-Jae
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.06a
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    • pp.531-533
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    • 2007
  • We report and discuss molecular and isotopic properties of hydrate-bound gases from 55 samples and void gases from 494 samples collected during Ocean Drilling Program (ODP) Leg 204 at Hydrate Ridge offshore Oregon. Gas hydrates appear to crystallize in sediments from two end-member gas sources (deep allochthonous and in situ) as mixtures of different proportions. In an area of high gas flux at the Southern Summit of the ridge (Sites 1248-1250), shallow (0-40 meters below the seafloor (mbsf)) gas hydrates are composed of mainly allochthonous mixed microbial and thermogenic methane and a small portion of thermogenic C2+ gases, which migrated vertically and laterally from as deep as 2-2.5 km depths. In contrast, deep (50-105 mbsf) gas hydrates at the Southern Summit (Sites 1248 and 1250) and on the flanks of the ridge (Sites 1244-1247) crystallize mainly from microbial methane and ethane generated dominantly in situ. A small contribution of allochthonous gas may also be present at sites where geologic and tectonic settings favor vertical gas migration from greater depth (e.g., Site 1244).

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Shallow gas origin in the sediment near coastal area of Busan (부산 주변 해역 해저 퇴적물 내 공기층 가스 기원)

  • Kim, Ji-Hoon;Han, Hyun-Chul;Cheong, Tae-Jin;Lee, Young-Joo
    • The Korean Journal of Petroleum Geology
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    • v.13 no.1
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    • pp.24-29
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    • 2007
  • The main purpose of this study is to identify the shallow gas origin in the KSSM zone. Based on the results of gas composition and isotope in the headsapace gas, the shallow gas is mainly composed of methane and carbon and deuterium isotopes (${\delta}^{13}CCH_4$ and ${\delta}DCH_4$) of methane has ranged from -93.4%o to -70.9%, and from -228%o to -199%o in each. These results imply that shallow gas has predominately biogenic source by $CO_2$ reduction rather than thermogenic. The carbon isotopic separation (${\varepsilon}_c$) between methane and carbon dioxide $(CO_2)$ has a range of 54.4 to 72.2, it also supports biogenic origin of shallow gas.

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The Characteristic and Origin of Organic Matter in the ODP Leg 204 Site 1249C and Site 1251B (ODP Leg 204 Site 1249C와 Site 1251B 퇴적물의 유기물 기원 및 지화학적 특성)

  • Shim, Eun-Hyoung;Yun, Hye-Su;Lee, Young-Joo;Han, Sang-Young
    • Economic and Environmental Geology
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    • v.47 no.1
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    • pp.71-85
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    • 2014
  • To study biogeochemical characteristics and origin organic matter, sediment samples were taken from Site of 1249C and Stie 1251B of ODP Leg 204. Data of Rock-Eval, isotope, and element analysis generally indicate dominance of marine organic matter in sediments deposited under marine sedimentary environment. Only Rock-Eval data are somewhat different from those of others owing to under-maturation of organic matter. Samples of Site 1249C show high content of gas hydrate, whereas Site 1251B low content of gas hydrate in some intervals of the core. This result may be accounted to different location of two cores and presence of transportation passage (Horizon A, BSR 2) of thermogenic gas in the core, 1249 C. However, Site 1251B Located in the basin of low accumulation of gas hydrate is presumed to be limited in the gas hydrate production. Because not only transportation passage is limited to move thermogenic gas from the core, but also gas supply was not enough. Therefore, the biogenic gas that resulted from diagenesis of there sediment is superior.

Geochemistry of Shallow gases taken from the core sediments in the southeastern Ulleung Basin (울릉분지 남동부 시추 퇴적물 내에 함유되어 있는 천부가스의 특성)

  • Lee Young joo;Huh Shik;Kwak Young hoon;Kim Hag ju;Chun Jong Hwa;Jun Sang Joon;Yoo Hai Soo
    • The Korean Journal of Petroleum Geology
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    • v.7 no.1_2 s.8
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    • pp.35-40
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    • 1999
  • Chemical and isotopic compositions of hydrocarbon gases were analyBed to characterize the properties of the shallow gases distributed in the southeastern part of the Ulleung Basin, offshore Korea. Sediments from the core were also analyzed to determine the characteristics and relationship to shallow gases. Hydrocarbon gases in the sediments consisted of methane (697.9-6054.4 ppm), ethane, propane, butane and hexane. The total carbon content of the sediments ranges from 1.84fe to $5.11{\%}$ and the total organic carbon content ranges from $0.29{\%} \;to\; 2.65{\%}$. High C/N ratio (>10) indicates that input of terrestrial organic matter was prevalent at the time of deposition. The methane content and stable isotopic data indicate that hydrocarbon gases from the sediments are identified to be thermogenic gas and mixture of both biogenic and thermal gases. Based on the Rock-Eval and carbon isotopic data, the level of thermal maturity of organic matter in the sediments $(Tmax<425^{\circ}C)$ is lower than that of gas. It suggests that thermal gases in the sediments migrated from the deeper sediments than the penetrated depth.

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Gas trasport and Gas hydrate distribution characteristics of Southern Hydrate Ridge: Results from ODP Leg 204

  • Lee, Young-Joo;Ryu, Byong-Jae;Kim, Ji-Hoon;Lee, Sang-Il
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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    • pp.407-409
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    • 2006
  • Geochemical analyses carried out on samples collected from cores on and near the southern smit of Hydrate Ridge have advanced understanding by providing a clear contrast of the two major modes of marine gas hydrate occurrence. High concentrations (15%-40% of pore space) of gas hydrate occurring at shallow depths (0-40 mbsf) on and near the southern summit are fed by gas migrating from depths of as much as 2km within the accretionary prism. This gas carries a characteristic minor component of C2-C5 thermogenic hydrocarbons that enable tracing of migration pathways and may stabilize the occurrence of some structure II gas hydrate. A structure II wet gas hydrate that is stable to greater depths and temperatures than structure I methane hydrate may account for the deeper, faint second bottom simulating reflection (BSR2) that occurs on the seaward side of the ridge. The wet gas is migrating In an ash/turbidite layer that intersects the base of gas hydrate stability on the seaward side of and directly beneath the southern summit of Hydrate Ridge. The high gas saturation (>65%) of the pore space within this layer could create a two-phase (gas + solid) system that would enable free gas to move vertically upward through the gas hydrate stability zone. Away from the summit of the ridge there is no apparent influx of the gas seeping from depth and sediments are characterized by the normal sequence of early diagenetic processes involving anaerobic oxidation of sedimentary organic matter, initially linked to the reduction of sulfate and later continued by means of carbonate reduction leading to the formation of microbial methane.

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Effects of Dietary Supplementation with a Compound Composed of Caffeine, Capsaicin, Sesamine, L-Carnitine, Banaba and Lotus on Human Autonomic Nervous System Activity and Lipid Oxidation

  • Kang, Sung-Hwun;Shin, Ki-Ok
    • Preventive Nutrition and Food Science
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    • v.14 no.3
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    • pp.173-178
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    • 2009
  • This study was conducted to determine if supplementation with a compound composed of caffeine (50 mg), capsaicin (75 mg), sesamine (30 mg), L-carnitine (300 mg), banaba (50 mg) and lotus (10 mg) enhanced human autonomic nervous activities (ANS) associated with thermogenic sympathetic activity and fat utilization. Ten healthy college males (21.2$\pm$1.0 yr) volunteered for this experiment. Autonomic nervous activities associated with energy metabolism were examined at 30 min intervals for a total of 120-min while at rest and every 5-min during exercise at 50% of the ventilation threshold before and after intake of the compound or placebo with 100 ml of water for 10 days. In addition, heart rate variability power spectral analysis was used to assess human autonomic nervous activities. The results indicated that there were no significant differences in heart rate during rest and exercise among trials. Furthermore, the autonomic nervous activity tended to increase after 10-days of consumption of the test compounds during the experimental period, but the differences did not reach statistical significance. However, before and after the compound test trial there was a significantly higher respiratory gas exchange ratio (rest 0: 0.83$\pm$0.01 vs. rest 3: 0.89$\pm$0.02, p<0.05), carbohydrate oxidation (CHO) rate (rest 0: 44.57$\pm$5.83 vs. rest 2: 63.86$\pm$5.91%, p<0.05) and a lower fat oxidation rate (rest 0: 55.43$\pm$5.83 vs. rest 2: 36.14$\pm$5.91%, p<0.05. In conclusion, the results of the present study suggested that the compound composed of caffeine, capsaicin, sesamine, L-carnitine, banaba and lotus components that was evaluated in this study did not induce a significant increase in human autonomic nervous activities or lipolysis, even though the individual components have been reported to induce increased fat oxidation.

Hydrocarbon Source Rock Potential of Eocene Forearc and Subduction Zone Strata, Southern Oregon Coast Range, U.S.A. (미국 오레곤 남부 에오세 전호상 및 섭입대 퇴적층의 탄화수소 근원암 가능성)

  • Ryu, In-Chang
    • The Korean Journal of Petroleum Geology
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    • v.11 no.1 s.12
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    • pp.27-41
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    • 2005
  • The hydrocarbon source rock potential of the Eocene units in the southern Oregon Coast Range was evaluated by using the Rock-Eval pyrolysis. Most Eocene units in southern Oregon Coast Range are thermally immature and contain lean, gas-prone Type III kerogen. However, some beds(coals) are sufficiently organic-rich to be sources of biogenic and thermogenic methane discovered in numerous seeps. The overall hydrocarbon source rock potential of the southern Oregon Coast Range is moderately low. Several requirements for commercial accumulations of hydrocarbon, however, probably exist locally within and adjacent areas. Three speculative petroleum systems are identified. The first includes the southern part of the Oregon Coast Range near the border with the Mesozoic Klamath Mountains and is related to a proposed subduction zone maturation mechanism along thrust faults. The second is centered in the northern part of the range and may be associated with basin-centered gas in an over-pressured zone. The third occurs near the eastern border of the range where maturation is related heating by sills and migration of hydrothermal fluids associated with mid-Tertiary volcanism in the Western cascade arc.

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Geochemical Characteristics of the Hydrocarbons from the Block 6-1, Ulleung Basin (울릉 분지 6-1 광구에서 발견된 탄화수소의 지화학적 특성)

  • Lee, Young-Joo;Cheong, Tae-Jin;Oh, Jae-Ho;Park, Se-Jin;Yi, Song-Suk
    • The Korean Journal of Petroleum Geology
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    • v.11 no.1 s.12
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    • pp.1-8
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    • 2005
  • Seventeen exploratory wells have been drilled in the Block VI-1 of offshore Korea, which is located in the southern part or the Ulleung Basin. Gas show has been recognized from most of the wells, and gas and condensate have been accompanied in some wells. Commercial discovery of gas, accompanied by condensate, has been made from Gorae V well. The reservoir gases or the Dolgorae III, Gorae I, and Gorae V wells in the Ulleung Basin mainly consists of hydrocarbon gases (>93%). These gases are thermogenic wet gases which contain more than 96% of the methane and result from the cracking of petroleum or kerogen. Based on the chemistry and composition of the gases and stable isotope data, they seem to be generated from different source rocks. The condensates from the Gorae I and V wells are mostly generated from terrestrial organic matter. Lacustrine organic matter may not play an important role for the generation of these condensates. The condensates from the Gorae V wells consist predominantly of terrestrial organic matter but with minor subsidiary input from marine organic matter. The condensates from Gorse I and V wells may be generated from different source rocks. The thermal maturity level of the condensates from the Gorae V well ranges from early to middle oil generation zone and condensate from Gorae I reaches middle oil window. Correlation or the thermal maturation level of the condensates and organic matter in the sediments reveals that a depth of the generation of liquid hydrocarbons can be inferred to 3,000 m and 3,900 m for the Gorae V and I wells, respectively. Gorae V well, however, did not reach the target depth and the geochemical data of the Gorae I well were obscured due to the severe sediment caving in.

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Alterations of Human Autonomic Nervous System Activity on Capsaicin Ingestion, and Variants of UCP1 and β3- -adrenergic Receptor Polymorphism (캡사이신 섭취와 UCP1 과 β3- adrenergic Receptor Polymorphism의 다양성에 대한 자율신경활동의 변화)

  • Ko, Ki-Jun;Shin, Ki-Ok
    • Journal of Life Science
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    • v.17 no.8 s.88
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    • pp.1075-1081
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    • 2007
  • We investigated whether 1) capsaicin ingestion (100 mg) enhances autonomic nervous system (ANS) activities associated with thermogenic sympathetic activity as energy metabolic modulator, 2) UCP1 and ${\beta}_{3}$-AR variants of each subjects influence with ANS activity. Eight healthy males (24.7 ${\pm}$ 1.8 yr) volunteered for this study. The cardiac autonomic nervous activities evaluated by means of heart rate variability of power spectral analysis and energy metabolism were continuously measured during 5-min rest for total 90-min resting condition with placebo or capsaicin oral administration chosen at random. The results indicated that there were no significant differences in heart rate during rest between both trials. Autonomic nervous activity increased in capsaicin tablet trial, but the difference did not reach the statistical significance. Capsaicin, however, induced significantly lower respiratory gas exchange ratio at Test3 (CAP: 0.80 ${\pm}$ 0.02 vs. 0.85 ${\pm}$ 0.02), means ${\pm}$ SE, p<0.05). In conclusion, it may be suggested the capsaicin consumption as a valuable supplement for the treatment of individual with hyperlipidemia and/or obesity by improving lipolysis. Further studies will also be considered genetic variants such as UCP1 and/or ${\beta}_{3}$-AR associated with obesity.