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A matured canola plant has different types of stems based on the diameter, such as narrow (immature), medium (mature), and wide (over mature). Therefore, this study was focused on investigating the properties of the extracted canola (HYREAR 3) fibers from 3 different diameter of stems (narrow, medium and wide). The physical (average length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of fibers were measured. ANOVA showed that stem diameter had effects on all fiber properties except for average length and elongation at break. Fiber diameter also had significant effects on load at break, elongation at break, aspect ratio, tensile stress, and young’s modulus. In corrgram, it was found that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were positively associated. Mean values showed that stem diameter had effects on all fiber properties except for average length. The mean values of fiber diameter, load at break, elongation at break, tenacity, and contact angle were highest and the lowest mean values were observed for tensile stress, young’s modulus and aspect ratio in fibers of 7 - 10 mm stems (medium matured), hence found to be less stiff. Moisture regain ability showed that canola fibers isolated from ≥8 mm stem diameter were more hydrophobic whereas contact angle measurement showed relatively more hydrophobic nature of 7 - 10 mm stem fibers. Therefore, this study provided an insightful understanding of the quality of the canola fibers of different stems which will ultimately help to choose the best stem to extract different qualities of fibers for commercial uses.

This paper deals with the rock physical analysis of primary reservoir rocks in the X gas field, which includes identifying the transition zone between mechanical and chemical compaction zones and the amount of cement in the reservoir rock. The analysis is performed by plotting different log data (Gamma-ray, density, neutron porosity, and sonic log) against depth, constructing the cross plot, and plotting of sonic and porosity logs with cement model. The transition zone, which is the boundary between mechanical and chemical compactions, indicates a sharp increase in density and a decrease in porosity with no lithological change at 2,576 m depth (Well-2). Among three gas sands, the upper gas sand and upper part of the middle gas sand are located within the mechanical compaction zone. The lower parts of the middle gas sand and lower gas sand are within the chemical compaction zone. Cement model analysis showed that the upper gas sand and upper part of the middle gas are composed of unconsolidated sand. In contrast, the lower part of middle gas sand and lower gas sand comprise of consolidated sand, having almost 2% contact cement.

The application of sequence stratigraphy to resolve the miscorrelation between different genetic units in reservoir characterization in a gas field of Surma Basin is dealt with. Interpretation of available seismic and wireline logs (gamma ray, resistivity, density and neutron porosity) give the sequence stratigraphic correlation of reservoir sands. The reservoirs geometry, its extent, seal architecture and trapping styles have been revealed better with this correlation. There is juxtaposition of two reservoir sands, namely A1 and A2. A1 is located at older highstand sand, whereas A2 is in the younger lowstand sand. Lithostratigraphically they might be same but sequences stratigraphy reveals that they are different and deposited at different times. Moreover, the concept reveals that lowstand sand has better reservoir quality than any highstand and transgressive sand. Asiat. Soc. Bangladesh, Sci. 45(2): 209-216, December 2019

This study builds a high-resolution sequence stratigraphic framework for the Surma Group in the X Gas field. At first, electrofacies and depositional sequences were interpreted from wire line logs. Then, the field wide configurations of these sequences have been identified in seismic using reflection terminations (of flap, onlap, top lap and down lap relationship). Finally, wire line log and seismic interpretations were integrated to establish sequences stratigraphic framework in the Surma Group. Electrofacies analysis has revealed four major facies associations namely: (i) Bell shaped fining upward facies corresponds to retrogradational shoreface to tidal flat deposits, (ii) Funnel shaped coarsening upward facies corresponds to progradational shoreface to tidal flat, (iii) Cylindrical aggradational facies interpreted as stacked channel and (iv) Symmetrical or Bow shaped facies corresponds to heterolithic unit. The succession of Surma group of about 3100+ m has been divided into twelve depositional sequences. With exception of depositional sequence 1, 11 and 12, most of them are composed of three system tracts: sandy lowstand system tract, shaley transgressive system tract and heterolithic to shaley highstand system tract. Repetitive occurrence of incised valley, shoreface sand as well as tidal channel sand separated by transgressive system tract shelfal mud resulted in sand-shale alternation in the Surma Group. The lower depositional sequences (up to sequence-6) are shale dominated and equivalent to the Lower Surma Group. The upper six sequences are sand dominated, have more channel incisions and sequence boundary representing the Upper Surma Group

The biggest question in the present gas crisis is where to find gas in the onshore of Bangladesh. The exploration strategies so far taken over the Surma Basin give importance only to the structural traps (fault-bounded anticlines). Already most of the anticlinal structures have been drilled and now they are at nearly matured stage. Therefore, most sustainable solutions are revising all the gas fields with sequence stratigraphic concept and find out the hidden possibilities of stratigraphic traps that are being still neglected. In this paper, interpretation of available logs and seismic has revealed the sequence stratigraphic concept of the reservoirs as well as new exploration prospect in the portion of Fenchuganj Gas field. The study reveals seven prospective reservoir zones, PR-1 to PR-7 from older to younger in studied area. Prospective reservoir PR-1 and PR-4 are belong to highstand system tract whereas PR-2, PR-3 and PR-5 are in the lowstand system tract. Upper two reservoirs PR-6 and PR-7 are located within the sand facies of transgressive system tract. Analysis of seismic attribute and log response has yield a prospective future drilling target in the erosional remnant of a highstand system tract truncated against lowstand-incised valley and capped by transgressive shale. Based on the seismic amplitude (bright spot), two exploration prospects were also identified in the stratigraphic traps located on the flank of the Fenchuganj structure. One is highstand sand truncated against shale-filled valley and the other one is lowstand channel sand sealed by transgressive shale, which demand further investigation. Thus, this approach provides new insights for local and international oil companies that there are huge possibilities of finding stratigraphic traps in the tidal deposits of regressive shelves that are yet to be well documented.