[U-09] How can we utilize leading measurements and SNS to create environmental / disaster prevention maps?

[U09-02] Development of Geological Information in Urban Areas using Three-dimensional Geological Model

★Invited Papers

*Susumu Nonogaki¹ (1.Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology)

Keywords:Geological information, Three-dimensional geological model, Borehole data, Urban areas

Shallow subsurface geological information plays an important role in evaluating earthquake-induced geological risk, such as ground motion amplification and liquefaction/subsidence, in urban areas. Recently, as part of the intellectual infrastructure development, Geological Survey of Japan (GSJ) has been working on creating three-dimensional (3D) geological maps of urban areas up to tens of meters in depth using borehole data obtained from drilling surveys for public construction works and for stratigraphic studies, cooperating with local governments. In addition, GSJ have been also working on developing a web-based system to visualize the developed geological information in easy-to-understand style. To date, the 3D geological maps of northern area of Chiba Prefecture and central Tokyo have been completed and are available for free on the website “Urban Geological Map” (https://gbank.gsj.jp/urbangeol/). On the website, the 3D geological model that consists of shape data of several geological boundaries, called “surface-based geological model”, can be visualized together with 3D representations of borehole data color-coded according to rock types and rock hardness. These 3D data are not only valuable for better understanding of shallow subsurface geological conditions, but they can also be readily applied to technologies such as digital twins. Therefore, they are expected to make contributions to urban planning, development, and management by considering earthquake-induced geological risk. The upcoming challenges for advancing data coordination with other fields involve are to make the developed geological data downloadable in multiple file formats and to implement a Web API for them. This presentation will provide an overview of the 3D urban geological map, focusing on its creation process and the functionalities available on the website.