TITLE:
Thickness, Distribution and Quality Assessment of Gopalganj-Madaripur Peat Deposits: A Case Study of Potential Economic Opportunities in Mid-Eastern Low-Lying Bangladesh
AUTHORS:
Mrinmoy Kumar Maitra, Md. Ashraful Islam, Md. Al Mamun
KEYWORDS:
Bengal Basin, Depression, Incipient Peat, Proximate Analysis
JOURNAL NAME:
International Journal of Geosciences,
Vol.5 No.9,
August
21,
2014
ABSTRACT: The
present research work illustrates the extent, distribution and a generalized
quality assessment of southern low-lying peat deposits in Madaripur and part of
Gopalganj district that covers approximately 17,000 hectare areas. Based on the
survey of 800 boreholes, drilled in this region at different times by several
government and non-government organizations for the purposes of peat
exploration and hydrogeological investigation, reveals that the study area is
composed of a considerable amount of peat deposits in various localities among
which the deposits at Baghia-Chanda beel in Madaripur and Gopalganj districts
are the most remarkable. The average peat thickness (in-situ condition), studied during field investigation, is 6.5 feet
for the upper peat deposits, overlying with an average of 3.5 feet of alluvium
cover, followed by the lower peat layer of about 3 feet thick that begins at an
average depth of 8 feet and separated by a thin bluish grey silty clay
sediments from the upper one. The lower part of the study area, locally known
as beels, is the most prospective region for peat, whereas the western part is
less potential either having no peat intersection or minimal peat thickness.
The overburden covers, on the other hand are inversely correlated with the peat
thicknesses, i.e., thick overburden
tend to correlate with thin peat deposits and the thickest peat intersections
have no or minimal overburden. Due to the variation in bulk density and peat
depth, this Holocene peat has an average of 59.10% carbon stock. Nitrogen
levels, more than 3%, indicate that the peat developed from the decomposition
of reeds, sedges, bushes and trunks of trees (higher in nitrogen) rather than
either moss or grass (lower in nitrogen). Higher sulphur content (about 2.7%)
reflected the influence of brackish environments where the formation of FeS2 took place in the roots of existing vegetation. The calorific values, about
1308.8 k-cal/kg (after 20% moisture reduction), suggest that the
Gopalganj-Madaripur peat is a low grade fuel that can be used as an alternative
energy source in the domestic and limited industrial purposes , to relatively
expensive natural gas and coal.