gas hydrate - CCOP

RESULTS
By Government:
The outcomes of the first two projects, Mae Tha and Mae Lamao, carried out by academic
institutions (see above), were inconclusive. This may be due to several factors such as
insufficient prior knowledge on drilling, well completion (PVC connecting), core sample
collection, field data collection procedures for gas and lab testing of core samples. Moreover,
there was lack of knowledge on the gas reserve calculation.
In 2006, the DMF made another attempt at CBM evaluation. The project site is at Mae Lamao
(Mae Sod Basin), in Northern Thailand. This time a private company was awarded the
contract and the exploration methodology was changed from the previous two projects. The
core samples (coal) were collected in a canister filled with water and then sent for laboratory
testing for gas volume and quality. As of now, the results are pending.
Mae Tha
Production and observation wells
The location of one production well and two observation wells were arranged in a triangular
pattern. Major factors that were considered include thickness of and continuity of coal beds,
depth of coal beds, and structural geology.
Construction of production and observation wells were commenced after drilling was
completed. This is the stage in which pipes are installed. The depth below the coal beds was
plugged with clay and plugged by cement above the coal up to the surface while at the depth
interval where coal beds were found, a screen was installed to allow coalbed gas to flow into
the well. Gravel pack is placed to coal bed up to 4 meters.
The depth interval where coal beds were found in both production and observation wells is
show in Table 1. The enclosing strata are made up of mudstone, claystone, shale, sandstone,
and unconsolidated clay. The coal-bearing strata are divided into the upper coal bed and the
lower coal bed. The upper coal bed is found at the depth of 12-16 meters with the thickness of
4 meters. The lower coal bed is found at the depth of 204-207.5 meters with the thickness of
3.5 meters. Between the upper and lower coal beds, mudstone and claystone, with an
aggregate thickness of 188 meters, are present in the depth interval of 16-204 meters.
Hole Name
Table 1. Coal Depth Interval
Total Depth (m.)
Depth to Coal
Seam (Top/bottom)
Coal
Thickness (m.)
MTO 1/46 213.00 200.80-202.20 1.40
MTO 2/46 220.00 195.50-198.20 2.70
MTP 1/46 209.00 204.00-207.50 3.50
134 New Energy Resources in the CCOP Region - Gas Hydrates and Coalbed Methane