gas hydrate - CCOP

Gas Hydrate Exploration in Korea
Keun-Pil Park
Gashydrate R&D Organization, Daejeon, Korea
EXTENDED ABSTRACT: Gas hydrates draw a great attention for the last 20 years as a
new clean energy resource substituting conventional oil and gas. Many countries including
USA, Japan, Canada, Germany, and India have launched extensive research programs to
study the characterization of gas hydrates and eventually to produce them from the ocean.
Results of preliminary survey by Korea Institute of Geoscience and Mineral Resources
(KIGAM) during the period of 2000~2004 showed that gas hydrates can be present in deep
sea area over 1,000 m water depth in the East Sea. From this optimistic conclusion,
government initiated 10 Year Gas Hydrates Development Program starting this year by
establishing "Gas Hydrates R&D Organization. 10 Year Gas Hydrates Development
Program consists of three stages with the final goal of commercial test production of gas
hydrates in 2015 with joint cooperation of Korea Gas Corporation (KOGAS), Korea National
Oil Corporation (KNOC) and KIGAM. The goal of the first stage is to identify the potential
area of gas hydrates in the prospect area I of the East Sea and retrieving the sample of the
natural gas hydrates by deep sea drilling as well as the development of production techniques.
For this purpose, studies of following 4 topics were performed with close interaction and
international collaborations; geological and geochemical studies, geophysical study, drilling
study, and production study.
Six piston cores had been acquired for geological and geochemical studies from the East Sea.
To analyze these sediments, we used X-ray diffraction analysis. The sediments consist of
quartz, feldspar, mica, amorphous opal-A, clay minerals, calcite, and pyrite. The most
dominant minerals are opal-A originated from siliceous diatoms. The opal-A increases to the
upper part of the piston cores, specially from the marginal side of the basin. Calcite minerals
decrease to the upper part of the piston cores. Cores from the deep basin area show
increasing of opal-A and decreasing of calcite minerals. On the other hand variations of
amount of opal minerals coincide with total organic carbon contents. This trend suggests that
the organic sediments in Ulleung Basin derived from siliceous algae.
The organic matters are dominantly originated from marine algae identified by isotope data.
The contents of TOC are mostly higher than 0.5% which indicates sufficient TOC for gas
hydrates formation. The contents of T max in the core sediments are lower than 435 o C which
indicates thermal immature stage for the organic matters.
High resolution seismic survey is a major tool to study the echo-characters of the seabed as
well as the subsurface geology. A data set of echo-sounding and high-resolution sub-bottom
profiles, acquired by the National Oceanographic Research Institute of Korea and Chungnam
National University in 1994-1996, was analyzed in order to understand the occurrence and
distribution of free gas within shallow sediments as well as the gas-related features on the
seabed in the southwestern part of the Ulleung Basin. High-resolution sub-bottom profiles
were collected using a Chirp sonar system (Datasonics CAP-6000 W) with a frequency band
of 2~7 kHz, which provides higher resolution images than those of the 3.5 kHz system. The
echo-sounding images were collected using a Precision Depth Recorder (Simrad EA 500)
with a 38 kHz frequency, which provide better images about the gas seepages and gas-related
New Energy Resources in the CCOP Region - Gas Hydrates and Coalbed Methane 17