The purpose of this paper is to estimate the extent of development of large (5 hectares or greater) residential sites in the Kitakyushu district from a geomorphological point of view. The results are summarised as follows. 1. Development of large residential sites in this district began around 1960, became intensified between 1965 and 1978, slowed down in 1979 and 1980 but has intensified again (Table 1). 2. The total number of large residential sites developed in this district is 155, and the total area developed is 3,574.9 hectares. 3. The geomorphological locations in which large residential sites have been developed are classified as 1) hills without summit planes (mostly composed of non-granitic rocks), 2) hills with summit planes (composed of granitic rocks and Palaeogene deposits), 3) terraces (Pleistocene), and 4) lowlands (Holocene alluvial plains). The area of large residential site development is 580.9 hectares in hills without summit planes, 2,477.3 hectares in hills with summit planes, 251.9 hectares in terraces, and 265.0 in lowlands. 4. The large residential sites in hills and terraces are reclaimed by the method of cutting spurs and filling valleys, maintaining a balance between the quantities of cut and fill. 5. Data were obtained on areas and quantities of earth moved in 33 residential sites in order to calculate the quantities of earth moved artificially for the development of large residential sites in this district. The mean depth of cut earth in hills without summit planes composed of non-granitic rocks is 7.0 metres, 12.6 metres in hills without summit planes composed of granitic rocks, 6.4 metres in hills with summit planes of the Ashiya group, 7.1 metres in hills with summit planes of the Nogata group, and 4.8 metres in terraces. The area of cut earth (1,383 hectares in total) is multiplied by the mean depth in each case. Thus the amount of earth moved in this district is about 93,000,000 m^3; and the mean depth of cut earth is 6.9 metres.
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