Acknowledgements

The authors thank IntechOpen for inviting us to write a chapter of this book and editor John Tiefenbacher for his sincere and fruitful comments during the revision process.

The microtremor recordings were provided by the Ministry of Planning and Sustainable Development of Trinidad and Tobago and are proprietary.

We used QGIS Open Software version 2.4 and the GCC Fortran Compiler to generate the maps presented in this work. The VS30 values used in this work were retrieved via WEB server at USGS (earthquake.usgs.gov/hazards/apps/vs30/) last accessed January 9, 2016.

The authors thank the Ministry of Planning and Sustainable Development of Trinidad and Tobago for funding this research being conceived by the first author as a principal investigator while working at the Seismic Research Centre in Trinidad

generated by the Diffuse Field Approach (DFA) with the observed ones at the array sites and with empirical formulas to estimate the average shear wave velocity of the upper 30 m (VS30). We conclude that the H/V ratios yield a genuine shear wave fundamental period of vibration of the soil profiles at POS, and that can be used to validate the high-resolution seismic microzonation map proposed by Salazar et al. [1]. The amplification and fundamental period of motion retrieved from the microtremors together with the water table level suggest a high liquefaction potential mainly on the coastal areas. It looks that in terms of seismic amplification and liquefaction hazard, a safe place is the Laventille area at the East characterized geologically by a metalimestone; unfortunately it is classified with the highest crime

Leaning lighthouse tower at the Port Area. See the displacement Δ at the top of the structure due to the soil

Natural Hazards - Risk, Exposure, Response, and Resilience

The genetic inversion results revealed that the deeper parts of POS are located in

the Port Area and South of Woodbrook with a depth of 225 m and the softer materials are located at the South East of POS in Sea Lots with low VS of 50 m/s which correspond to a buried swamp or mangrove; toward the north of the City, the depth of the sediments decreases substantially from 75 m in the Savannah to 30 m in Saint James and Cocorite to the West. Toward the South East part of POS in Sea

rate and drug dealers in Trinidad.

Figure 14.

74

subsidence at its foundation.

during 2008–2014. We thank also all the governmental institutions in Trinidad that permit to do the survey in their facilities. We greatly acknowledge Hiroaki Yamanaka (Tokyo Institute of Technology) for providing the first author the original Fortran Codes of Genetic Inversion through the sponsor of the Japanese International Cooperation Agency (JICA) in El Salvador. The Tokyo Sokushin personnel in Japan were always assisting us with our queries regarding the microtremor instrumentation. The authors want to thank Francisco Sánchez-Sesma from Universidad Autónoma de México UNAM for sharing with the first author the Diffuse Field Approach program to compute the synthetics of H/V ratio. His unconditional help has made possible to update this chapter to better understand the amplification phenomena employing microtremor measurements at Port of Spain.

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