동해 울릉분지 남서부 해역에서의 가스 하이드레이트 안정영역

류병재,선우돈,장성형,오진용,Ryu Byong Jae,Don Sun woo,Chang Sung Hyong,Oh Jin yong 한국석유지질학회 1999 한국석유지질학회지 Vol.7 No.1

천연가스 하이드레이트는 고압 ·저온 조건하에서 물과 천연가스가 결합하여 형성된 고체상 화합물로 일반적으로 가스 하이드레이트로 불리며, 영구동토지역과 수심이 깊은 해저의 퇴적층에 광범위하게 분포되어 있다. 가스 하이드레이트 안정영역은 하이드레이트가 형성된 후 해리되지 않고 고체상으로 안정하게 부존될 수 있는 영역이다. 반사법 탄성파 단면 도에서 관찰되는 해저면 모방 반사면 (bottom simulating reflector; BSR)은 가스 하이드레이트의 부존을 지시하는 강진 폭의 반사면으로 가스 하이드레이트 안정영역의 하한에서 나타난다. 본 연구에서는 동해 울릉분지 남서부해역에서의 가스 하이드레이트 안정영역을 규명하고 탐사자료와 비교하여 가스 하이드레이트 부존 잠재력을 밝히고자 하였다. 연구지역에서 XBT (expandable bathythermograph)를 이용하여 수온구배를 측정하였으며, 지온구배는 인접지역의 시추공 자료를 이용하였다. 실험실에서 메탄가스와 NaCl $3.0 wt{\%}$수용액을 이용하여 가스 하이드레이트 평형압력은 274.15 K에서 2,920.2 kPa 그리고 289.95 K에서 18,090 kPa로. 측정되었다 연구지역에서의 가스 하이드레이트 안정영역 분석 결과 수심이 약 400 m인 지역의 경우 가스 하이드레이트 안정영역의 하한은 해저면으로부터 심도 약 210 m에, 수심이 1,100 m인 경우에는 해저면으로부터 심도 약 480 m에 위치하는 것으로 밝혀졌다. 또한 탄성파 탐사자료와 안정영역 분석 결과를 비교하여 볼 때 BSR이 나타나는 심도가 안정영역 하한의 심도와 거의 일치하였다. Natural gas hydrate, a solid compound of natural gas (mainly methane) and water in the low temperature and high pressure, is widely distributed in permafrost region and deep sea sediments. Gas hydrate stability field (GHSF), which corresponds to the conditions of a stable existence of solid gas hydrate without dissociation, depends on temperature, pressure, and composition of gas and interstitial water. Gas hydrate-saturated sediment are easily recognized by the bottom simulating reflector (BSR), a strong-amplitude sea bottom-mimic reflector in seismic profiles. It is known that BSR is associated with the basal boundary of the GHSF, The purpose of this study is to define the GHSF and its occurrence in the southwestern part of Ulleung Basin, East Sea. The hydrothermal gradient is measured using the expandable bathythermograph (XBT) and the geothermal gradient data are utilized from previous drilling results for the adjacent area. By the laboratory work using methane and NaCl $3.0 wt{\%}$ solution, it is shown that the equilibrium pressures of the gas hydrate reach to 2,920.2 kPa at 274.15 K and to 18,090 kPa at 289.95 K for the study area. Consequently, it is interpreted that the lower boundary of the GHSF is about 210 m beneath 400-m-deep sea bottom and about 480 m beneath 1,100-m-deep sea bottom. The resultant boundary is well matched with the depth of the BSR obtained from the seismic data analysis for the study area.

서부 울릉분지 천부 퇴적층의 탄화수소

류병재(Ryu, Byong-Jae),김지훈(Kim, Ji-Hoon),이영주(Lee, Young-Joo),김일수(Kim, Il-Soo) 한국신재생에너지학회 2007 한국신재생에너지학회 학술대회논문집 Vol.2007 No.11

Studies on the hydrocarbons in shallow sediments of the East Sea of Korea have been carried out by the Korea Institute of Geoscience and Mineral Resources (KIGAM) since 2000. 4946 L-km of 2D multichannel reflection seismic data, 3250 L-km of high-resolution Chirp profiles and 16 selected piston cores were analyzed to determine the presence of hydrocarbons in shallow sediments of the western deep-water Ulleung Basin. The seismic data show a number of blanking zones that probably reflect widespread fluid and gas venting. The blanking zones are often associated with velocity pull-up structures. These upwelling structures are interpreted to be the result of high-velocity natural gas hydrate. There are also several bottom-simulating reflectors that are associated with free gas and probably overlying gas hydrate. Numerous pockmarks were also observed in the Chirp profiles. They are seafloor depressions caused by the removal of near-seafloor soft sediments by escaping of fluid and gas. In piston cores, cracks generally oriented parallel to bedding suggest significant gas content some of which may have been contained in gas hydrate in situ.

울릉분지 가스 하이드레이트 2차 시추

류병재(Ryu, Byong-Jae),이성록(Lee, Sung-Rock),유동근(Yoo, Dong-Geun),김길영(Kim, Gil-Young),천종화(Chun, Jong-Hwa),박장준(Bahk, Jang-Jun),김지훈(Kim, Ji-Hoon),이주용(Lee, Joo-Yong) 한국신재생에너지학회 2011 한국신재생에너지학회 학술대회논문집 Vol.2011 No.05

지식경제부 가스 하이드레이트 개발사업의 일환으로 동해 울릉분지 가스 하이드레이트 2차 시추(Ulleung Basin Gas Hydrate Drilling Expedition: UBGH2)가 2010년 7월 8일부터 9월 30일까지 D/V Fugro Synergy를 이용하여 수행되었다. UBGH2 수행을 위해 선정된 13개 site에서 약 1개월 동안 Schlumberger사의 장비를 이용 Logging-While-Drilling/Measurement-While-Drilling(LWD/MWD) 자료를 취득하였다. LWD/MWD 자료는 선상에서 분석되었으며, 이 결과는 coring 및 borehole plan 수립을 위하여 활용되었다. Coring Phase 동안 10개 site의 18개 hole로부터 퇴적물 코어 시료를 채취하고 선상에서 퇴적학, 지구화학, 생지화학, 물리적 특성 등 각종 분석과 측정 작업을 수행하였다. 약 2개월에 걸쳐 수행된 coring phase 동안에 2개 site에서 FAOL(Fugro Alluvial Offshore Limited)사의 장비를 이용 Wireline Logging/Vertical Seismic Profile(WL/VSP) 자료도 취득하였다. LWD/MWD phase와 coring phase 동안 12개 site에서 무인잠수정(remotely operated vehicle: ROV)를 이용하여 퇴적물 시료 채취, 해저면 관찰, 용존메탄 측정 등의 작업을 수행하였으며, 선상에서 취득된 이들 자료를 분석하였다. Coring을 수행한 모든 site에서 가스 하이드레이트 부존을 확인하였으며, 다양한 산상의 가스 하이드레이트 실물을 회수하고 분석하였다.

울릉분지 서부에서의 탄화수소 생성 및 지표

류병재(Ryu, Byong-Jae),김지훈(Kim, Ji-Hoon),이영주(Lee, Young-Joo),김일수(Kim, Il-Soo) 한국신재생에너지학회 2007 한국신재생에너지학회 학술대회논문집 Vol.2007 No.06

Piston cores retrieved from the western Ulleung Basin, East Sea were analyzed to examine the potential for hydrocarbon generation and to determine the hydrocarbon indicators. 2D multi-channel reflection seismic and Chirp data were also investigated for mapping and characterizing the geophysical hydrocarbon indicators such as BSR (bottom simulating reflector), blank zone, pock-mark etc. High organic carbon contents and sedimentation rates that suggest good condition for hydrocarbon generation. High pressure and low temperature condition, and high residual hydrocarbon concentrations are favor the formation of natural gas hydrate. In the piston cores, cracks generally oriented to bedding may indicate the gas expansion. The seismic data show several BSRs that are associated with natural gas hydrates and underlying free gas. A number of vertical to sub-vertical blank zones were well identified in the seismic sections. They often show the seismic pull-up structures, probably indicating the presence of high velocity hydrates. Numerous pockmarks were also observed in the Chirp profiles. They may indicate the presence of free gas below the hydrate stability zone as well.

우리나라 가스 하이드레이트 연구 · 개발

류병재(Byong-Jae Ryu) 한국신재생에너지학회 2016 신재생에너지 Vol.12 No.3

Gas hydrate project in Korea was initiated by Korea Institute of Geoscience and Mineral Resources (KIGAM) in 1996. To understand the potential of gas hydrate presence in the Ulleung Basin, East Sea, KIGAM collected the geophysical data and sediment samples in the southwestern part of the basin from 1997 to 1999. Bottom simulating reflector firstly was identified from the seismic data acquired in 2008. Regional geophysical surveys and geological studies have been also carried out by KIGAM from 2000 to 2004. KNOC also collected seismic data from 2001 to 2003. Based on the results from these preliminary researches, “Korean National Gas Hydrate Program” was launched in 2005. The program has been supported by the government, and carried out by KIGAM, KNOC and KOGAS under the management of Gas Hydrate R&D Organization. The program has undertaken geophysical survey programs and coring for the identification of gas hydrate occurrences, the assessment of gas hydrate resources in the basin, development of optimum production technology, environmental impact studies, and test production. The gas hydrate test production which originally was planned to be performed in 2015, is postponed to study further for safer and more successful testing. Currently, the second national program is being planned.

동부 심해 울릉분지의 천연가스 하이드레이트

류병재(Ryu, Byong-Jae),김지훈(Kim, Ji-Hoon),정부흥(Chung, Bu-Heung),이영주(Lee, Young-Joo) 한국신재생에너지학회 2008 한국신재생에너지학회 학술대회논문집 Vol.2008 No.05

Piston cores retrieved from the eastern part of the deep-water Ulleung Basin were analyzed to access the potential of hydrocarbon gas generation and natural gas hydrate (NGH) formation. Seismic data acquired in the study area were also analyzed to determine the presence of hydrocarbon gas and/or NGH, and to map their distribution. Core analyses revealed high total organic carbon (TOC) contents which favor hydrocarbon generation. The cores recovered from the southern study area showed the sufficient residual hydrocarbon gas concentrations for the formation of significant NGH. These cores also showed the cracks developed parallel to the bedding that suggest significant gas content in situ. A number of seismic blanking zones were observed on seismic data. They are identified as vertical to sub-vertical chimneys caused by the upward migration of pore fluid or gas, and containing of free gas and/or NGH. Often, they are associated with velocity pull-up structures that are interpreted to be the result of high-velocity NGH. The seismic data also showed several bottom-simulating reflectors (BSRs) that are associated with overlying NGH and underlying free gas. The distribution of blanking zones and BSRs would be impacted by the lateral differences of upward methane fluxes.

우리나라 천연가스 하이드레이트 연구·개발

류병재(Byong-Jae Ryu) 한국신재생에너지학회 2015 한국신재생에너지학회 학술대회논문집 Vol.2015 No.11

우리나라 동해의 가스 하이드레이트

류병재(Byong-Jae Ryu) 한국신재생에너지학회 2016 한국신재생에너지학회 학술대회논문집 Vol.2016 No.5

동해 울릉분지 침니구조 내의 가스 하이드레이트

류병재(Byong-Jae Ryu) 한국신재생에너지학회 2016 한국신재생에너지학회 학술대회논문집 Vol.2016 No.11

우리나라 동해 울릉분지의 천부 가스 하이드레이트

류병재(Byong-Jae Ryu) 한국신재생에너지학회 2017 한국신재생에너지학회 학술대회논문집 Vol.2017 No.9