1. Landslide hazard analysis for Hong Kong
using landslide inventory and GIS
K.T. Chau, Y.L. Sze, M.K. Fung, W.Y. Wong, E.L. Fong, L.C.P. Chan
指導教授 段錦浩
報告 張立農
秦宇正
2012/12/7

2. program
Introduction
Introduction to the geological and Climate of Hong Kong
Landslides hazard analysis based on landslide inventory
Use of GIS to analyzing landslide hazard
Conclusion

3. Introduction
GIS technology has been used virtually everywhere in the world, including both developed and developing countries.
A reliable landside hazard map should carry appropriate weight.
The main objective of the present study is to consider more comprehensively the landslide hazard of Hong Kong Island.

4. program
Introduction
Introduction to the geological and Climate of Hong Kong
Landslides hazard analysis based on landslide inventory
Use of GIS to analyzing landslide hazard
Conclusion

5. Geological conditions
Hong Kong:
Hong Kong Island
Kowloon
New Territories
Hong Kong Island
Lithology :
volcanic rock(tuff)
intrusive rock(granite)
Deposit :
weathered from volcanic rock
Terrain:
hilly to mountainous
steep slopes exceeding 30°
highest point is 554m

6. Climatic conditions Hong Kong: Hong Kong Island Kowloon
New Territories
Hong Kong Island
sub-tropical
winter temperature of exceeding 10°C
summer temperature of exceeding 31°C
rainfall range between 1300mm and 3000mm
80% of the rain falls between May and September

7. program
Introduction
Introduction to the geological and Climate of Hong Kong
Landslides hazard analysis based on landslide inventory
Use of GIS to analyzing landslide hazard
Conclusion

8. Diurnal and seasonal distribution for landslides
Diurnal frequency of landslides in Hong Kong (1948–1996), and a total of 623 data have been used.

9. Diurnal and seasonal distribution for landslides
Seasonal variations of average landslide frequency
seasonal distributions of
rainfall and temperature

10. Diurnal and seasonal distribution for landslides
Monthly variations of temperature, rainfall and its relation to landslides in 1990 and A total of 70 landslide data were used.

11. Fatalities and injuries rate
Cumulative fatalities, injuries and rainfall in Hong Kong from 1948 to A total of 556 fatalities and 570 injuries were reported.

12. Facilities risk rate
Cumulative number of landslides affecting various facilities and utilities.
( )

13. Facilities risk rate

14. Landslide hazard in different geological formations
landslide on soil types
( ,312data)

15. Frequency and volume relation of landslides
Cumulative number of landslides per year versus volume of landslide.( ,594data.)

16. Just only landslide data
Landslide hazard map
Just only landslide data
A total of 921 landslide data was used from 1984 to 1996.Values of six levels of contour lines are for 0.25, 0.75, 1.25, 2, 4,and 5 units and each unit corresponds to 1.23 landslide per year per km*km

17. program
Introduction
Introduction to the geological and Climate of Hong Kong
Landslides hazard analysis based on landslide inventory
Use of GIS to analyzing landslide hazard
Conclusion

18. Layers of information for multi-dimensional regression analysis

19. Hazard analysis using raster calculation

20. Hazard analysis using raster calculation
T1=elevation T2=slope
E1=rainfall
L1=potential runout of landslides L2=landslide inventory
G1=soil deposition G2=geology

21. Risk analysis using raster calculation
W1=W6=0
Others=1
W6=0
Others=1
W6=2
Others=Table1
All=Table1

22. Risk analysis using raster calculation
Risk(x) = Hazard(x) * Exposure(x)

23. program
Introduction
Introduction to the geological and Climate of Hong Kong
Landsides hazard analysis based on landslide inventory
Use of GIS to analyzing landslide hazard
Conclusion

24. Conclusion
The framework of landslide hazard analysis and the potential use of GIS discussed here should provide a yardstick for further landslide hazard analysis of Hong Kong. In addition, landslide-dynamics-based numerical simulations should be included in the hazard analysis so that subjective, and potentially bias, expert opinion can be avoided. Such incorporation of landslide dynamics analysis with GIS should result in a more reliable landslide hazard map for city planning and its potential misuse can be minimized.

25. Thanks for your listening