The present research work mainly deals with the qualitative and quantitative analysis of heavy minerals of the Neogene sandstones (Plio-Miocene) and beach sands of the Inani-Dakhin Nhila area and also deals with preliminary approach on chemical composition of garnets and ilmenites to infer the provenance. The Neogene sandstones of the Inani-Dakhin Nhila hill ranges contain about 2% heavy minerals whereas the beach sands of the Inani-Dakhin Nhila area contain about 8% heavy minerals.
The heavy mineral assemblages of the sands/sandstones of the Inani-Dakhin Nhila area are characterized by clear predominance of opaque minerals (with abundant ilmenite), epidote, garnet, staurolite followed by hornblende and tourmaline, lesser amounts of zircon, rutile and kyanite and by minor to trace amounts of apatite, sillimanite, monazite and sphene. The heavy mineral data suggest a wide range of metamorphic as well as granitoid source areas. The heavy mineral suites reflect that the probable sources of the clastics which have contributed to the study area of interest is located in the north, northwest and east-northeastern part of Bangladesh. These detrital grains could have been derived from crystalline and sedimentary deposits of the Himalayas, Rajmahal hills, Shillong Plateau and Indo-Burman ranges.

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Infrared spectra of pollen grains of Picea from two peat beds of Pleistocene were obtained by Akiyama et al. (1992). We have applied their technique to the individual fossil pollen grains separated from the ordinary sedimentary rocks. To measure infrared spectra by a micro-transmission-reflection method, we made a sample foundation of a sheet of aluminum foil and clay put on a slide glass, and found individual fossil pollen grains in organic matter spread on the sample foundation under a stereoscopic microscope. We can obtain an infrared spectrum for an individual fossil pollen grain, using a Fourier transform infrared spectroscopy with an infrared microscope (micro-FTIR). Intensities of functional groups of OH, aliphatic CH₂, C=O, and aromatic C=C on an infrared spectrum for an individual fossil pollen grain may reflect organic maturation of the sedimentary rock including the fossil pollen.

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Modern sedimentology in Japan has been developed into a systematic organization mainly by the efforts of Prof. Kazuo Taguchi of Tohoku University. Prof. Taguchi was the sedimentologist who established chemical sedimentology in Japan. Here the sedimentological efforts of Prof. Kazuo Taguchi are presented based on his scientific contributions.

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