Kiribati, Betio to Bairiki, 1981, Causeway Site Survey, Figure 10, Seismic Profile #3

This record shows the Seismic Interpretation obtained at the Betio-Bairiki causeway site in 1981. The data was obtained as part of the Tarawa Nearshore project. The chart shows 2 profiles. There are another 9 sheets accompanying this one that belong to the same project. The map was drawn up as part of the Tarawa Nearshore Project for the Bairiki-Betio, Tarawa causeway dredging borrow site. Sea bed surveys were undertaken in south Tarawa by UNDP staff and consultants assisted by personnel supplied by the government of Kiribati during November and December 1981. A copy of the map can be downloaded by selecting the appropriate link under 'Online resources' with permission from the Secretariat.To provide material for the construction of a road causeway, and possibly an airfield, linking Betio and Bairiki islands. Also, to undertake a geophysical survey to attempt to extrapolate the borehole data over the whole area of interest and to obtain as much additional data as possible on the nature of the sea bed and sub-bottom soils materials and to gather a certain amount of marine baseline environmental data from the site of the proposed causeway and lagoon borrow pit, and from nearby areas. It is intended that this data should in part provide a basis for determining the long term effects of the causeway construction.There are 2 scales provided:Horizontal: 1: 1000Vertical: 1: 250The work was undertaken as part of the CCOP/SOPAC work programme elements CCSP-1/KI.4 (Surveys for Landfill/Construction Materials) and CCSP-1/KI.5 (Coastal Zone Surveys on Sedimentation, Erosion and Pollution Problems). The Marine Superintendent at Betio has reported possible changes in the shallow areas in the main Betio shipping channel since the major hydrographic survey carried out by H.M. survey ship COOK in 1959. In order to update this survey soundings were made across the width of the main shipping channel from Betio to the western reef entrance.