@article{oai:nagasaki-u.repo.nii.ac.jp:00007435, author = {近藤, 寛 and 石渡, 良志 and 山本, 修一}, journal = {長崎大学教育学部自然科学研究報告, Science bulletin of the Faculty of Education, Nagasaki University}, month = {Feb}, note = {Imari Bay lies in the north-western part of Kyushu with the Takasima Is. at the bay-mouth and the Fukushima Is, in the cetral bay, copening north-westward into Genkainada open sea. The bottom sediments were divided into four groups, that is , calcareous muddy sand, calcareous mud, mud, muddy sand, by the contents of mud and calcium carbonate. Eight sediment samples have been analysed for aliphatic hydrocarbons (n-alkanes), aliphatic alcohols (n-alcohols), 4-methyl-sterols and 4-desmethyl-sterols in term of their area distribution, and in relation to the types of sediments. Distribution of n-alkanes having a high odd/even carbon number preference with a maximum at n-C29 or n-C31 show a predomkinant contribution of terrestrial higher plants. L/H values (L≦n-C20,H≧n-C21) of n-alkanes for the calcareous sediments from the strait and the bay-mouth area are relatively high (L/H=0.13 at St. 3, 5). Low L/H value for the muddy sand from the bay head (L/H=0.10 at st. 8) due to an influx of terrigenous higher plants which contain high concentrations of ≧n-C21from the Arita and Imari rivers. n-Alcohols ranging from n-C14 to n-C28 show even carbon number predominance and a maximum at n-C22 or n-C24. These ≧n-C22 alcohols were derived from the higher plants of terrestrial source. In the lower molecular weright range (