8CUEE CONFERENCE PROCEEDINGS
8th International Conference on Urban Earthquake Engineering
March 7-8, 2011, Tokyo Institute of Technology, Tokyo, JapanTHE TSUNAMI OF CAMANA 2001

Cesar Jimenez1), Bruno Adriano2), Shunichi Koshimura3), and Yushiro Fujii4)
1) Assistant Professor, University of San Marcos UNMSM, Peru
2) Researcher, CISMID, National University of Engineering, Peru
3) Associate Professor, Department of Civil Engineering, Tohoku University, Japan
4) International Institute of Seismology and Earthquake Engineering, Japancjimenez@pucp.edu.pe, badrianoo@uni.edu.pe, koshimura@tsunami2.civil.tohoku.ac.jp, fujii@kenken.go.jp

Abstract: On 23 June 2001, at 15:33 local time, the Camaná city and all the peruvian southern region were hit by astrong earthquake of magnitude 8.4 Mw and maximal intensity VIII in Mercalli scale, the epicenter was located on the sea
in the forefront of Ocoña (Arequipa). 15 minutes later a localized tsunami was generated, which destroyed the seaside
town of Camana and caused the death of 24 people and 62 missing people. With the help of numerical modeling TIME
and the use of computers, it is possible to make the numerical simulation of tsunami and to obtain parameters such asarrival times, run up (maximal height of flooding), synthetic tidal gage recordings and flooding maps, which will be
useful for disaster mitigation for the corresponding authorities.

1. INTRODUCTION
A tsunami is a series of water waves of great length(with periods ranging from 5 to 60 minutes, or higher),
generated by mechanisms such as volcanic explosions onislands, underwater landslides, falling rocks or bays ocean
and tectonic movements associated with earthquakes. An
earthquake tsunami generator is usually associated withsubduction zones. Since many of these areas are along thePacific Rim, the vast majority of tsunamis occur in thePacific Ocean.
Tsunamis are classified in the place of arrival to thecoast, according to the distance (or travel time) from theirplace of origin, in:a) Local Tsunami, if the place of arrival on the coast isvery near or within the area of generation (defined by thearea of seafloor displacement) of the tsunami, or less than
one hour travel time from the beginning.
b) Distant Tsunamis, if the place of arrival is more than
1000 km away from the zone of generation or end-opposite
shores across the Pacific Ocean and about half a day or moreof the tsunami travel time from that area (Jimenez, 2008).
According to the testimonies of survivors, shortly
before the earthquake a refolding of the sea in some places
and then the earthquake on 15 minutes started the tsunami
destroyed the resort of Camaná. This was a small local
tsunami that affected only Camaná coastal resorts. The
height of the waves reached up to 7 m in some places, with arun-up to 7 m and a maximum flooding distance of 1350 m.
There were 24 dead and 2 missing and large losses. Thistunamigenic earthquake is the strongest since 1868 in thesouthern region of Peru. The period of recurrence of thistype of event for the region of Peru and northern Chile is of
100 years (Kulikov et al., 2005).
The parameters obtained by the Geophysical Institute ofPeru (IGP) were:
Local Time = 15h 33m 23 June 2001
Latitude = -16.20 ºLongitude = -73.75 º
Depth = 29 km
Magnitude Mw = 8.4
Intensity = VIII Ocoña, Camana
Location: 82 miles north west of Ocoña (Arequipa)
1.1 Area of study
Camana province is located in the Midwestern part of
the Arequipa region to 172 km from the capital of theDepartment of Arequipa, and has about 56 thousand
inhabitants. This is the first city that sent the conqueror
Francisco Pizarro founded. Predominant economic activity
is agriculture. Bounded on the north by the province
Condesuyos, province of Castilla, Arequipa province (SanJuan de Siguas) for the north-west province Caravelí andPenthouse, on the south by the Pacific Ocean on the east by
the province of Islay. In 2001 a strong earthquake rocked theregion and a tsunami devastated the coastal resorts of thecity of Camana.

2. FOCAL PARAMETERS CALCULATION
From the empirical relationship of Papazachos 2004,
between the seismic moment magnitude Mw and the focal
parameters: length L (km), width W (km), and displacement- 1567 -U (cm) of the failure to subduction zones :log( L) = 0.55M − 2.19log(W ) = 0.31M − 0.63
log(U ) = 0.64M − 2.78

(1)

The following results were obtained for Mw = 8.4:
Rupture lengthL = 269 km
Rupture width
W = 94 km
Fault displacement:
U = 3.9 m
The seismic moment Mo is defined as: Mo = μLWU =4.9*1021 Nm, where μ = 4.5*1010 N/m2 is the modulus ofthe medium. Talandier 1993, provides a relationshipbetween seismic moment Mo and the destructive potential ofa tsunami. The value of Mo indicates that the Camana
earthquake generated a small tsunami (Talandier, 1993).
However, it was destructive in the area of the coastal resorts
due to the vulnerability of buildings.
Table 1. Classification of tsunamis according Talandier.
Value range
Mo < 1021 N.m
1021 < Mo < 5*1021 N.m
5*1021 < Mo < 2*1022 N.m
Mo > 2*1022 N.mTsunami typeNo tsunami was generated
Small tsunami
Potencially destructive
Great and destructive

3. DATA AND SELECTION OF THE DOMAIN OF
INTEGRATION
To model the tsunami flood zones need the following
information:a) Global bathymetry grid.- To simulate the largest
where the tsunami spread. The data are taken Etopo2 modelwith a resolution of 3.6 km (Smith, 2006).
b) Local bathymetry.- These fine details are obtained
from drilling conducted in the area.
c) Local topography.- To model the flooding caused by
the tsunami. Data are taken on-site survey and satellite
survey data SRTM 90 (Jarvis et al., 2006).
With all these data we obtain a digital elevation modeland proceeds to draw 4 nested grids: A, B, C and D (seeFigure 1). Where grid A is the largest and contains the areaof rupture. The grid D is the smallest, but the data are finest
and contains the region where we want to evaluate the flood.
The boundaries of the grid are:region_a = [-20 -13282.0
region_b = [-17 -15.8 285.5
region_c = [-17 -16.2 286.5
region_d = [-16.85 -16.59 287.258

Fig. 1 Nested grids for the present model

4. TSUNAMI GENERATION PHASE
For an earthquake generates a tsunami is necessary tomeet the following requirements:a) The epicenter of the earthquake, or a majority of its
rupture area, is under the seabed at a depth less than 60 km(shallow earthquake).
b) Occurring in a sink edge of tectonic plates in the sea,
ie the failure to have vertical movement and is not just lateral
strike slip motion.
c) The earthquake releases enough energy in a certain
period of time and this is efficiently transmitted. In general,magnitude Mw > 7.0.
The initial condition of tsunami (strain field due todisplacement or fault line) is determined using the model ofMansinha and Smylie (1971) assuming an instantaneous
deformation of the ocean's surface equal to the verticalcomponent of the strain field of the bed ocean. This is amodel of fracture and requires knowledge of the earthquake
focal mechanism (Okal, 2002). It has been considered thefollowing values:
Strike angle = 301º
Dip angle = 20º
Slip angle = 90º

290.0 ];
287.5 ];
287.5];
287.373];

Fig. 2 Model of initial co-seismic deformation.

- 1568 -For this model the maximum height of the deformation
is of 2.04 m. This creates the "piston effect" that destabilizes
the water column causing tsunami waves.

linear equations for the propagation of the tsunami throughthe ocean floor in shallow water:∂η+ ∇.U = 0∂t
∂U+ gh∇η = 0∂t(2)(3)where η is the disturbance of sea level, U represents thevelocity field, g is the acceleration of gravity, h is the depth
and t is time. In Figure 5 shows the initial stage ofpropagation of tsunami waves for the homogeneous slip
model.

Fig. 3 Contours of initial co-seismic deformation.
Using the inversion of the tsunami waveforms fromtidal gauge stations is possible to get the source parameters
for a heterogeneous slip model as shown in Figure 4(Adriano, 2010).

Fig. 5 Start time of Tsunami Propagation

6. INUNDATION PHASE OF TSUNAMI

Fig. 4 Heterogeneous slip model from inversion oftsunami waveform data (Adriano, 2010).

5. PROPAGATION PHASE OF TSUNAMI

The height reached by a tsunami, upon reaching thecoast is due to the interaction of various physical andmorphological factors such as characteristics of waves at sea,
bathymetry, seabed slope, configuration of the sea boundary,diffraction, refraction, reflection, dispersion of the normal
modes of resonance of the coastal formations and theformation of bores on beaches, estuaries and coastal lagoons.
These factors determine that the arrival of the tsunami on thecoastline is a complex process, which generates significant
differences in height of the tsunami even over shortdistances along the coast.
In Figure 6 shows that the maximum wave height(according to model) to the shoreline was 9 m at the position
corresponding to -72.75 degrees longitude (outside the areaof interest: grid D). The maximum wave height is 7 m.

The propagation of the tsunami is simulated with themodel of Goto and Ogawa (1982) that integrates the shallow
water equations by the numerical method of finite
differences. The TIME model (and other models) uses the- 1569 -Fig. 8 Flooding map from the heterogeneous slip model(Adriano, 2010).
Fig. 6 Maximum wave height along the coast.

In Figure 7, we can see a tsunami inundation map
according to the homogeneous slip model for Camana area.
The narrow strip for the seaside resort (right side) iscompletely flooded, with the South Panamerican highway
and the adjacent hills as boundary. The maximum horizontal
inundation distance is about 1350 m, according to thismodel.

Figure 9 shows an aerial photograph in which is traced
the flooding observed, it appears that the homogeneous slip
model agrees quite closely with the observation in situ, thus
validating this modeling tsunami inundation.

Fig. 9 Flooding map as in-situ (Source: DHN)

Fig. 7 Flooding map from the homogeneous slip model(scale in meter).

In Figure 8, we can see the inundation map for theheterogeneous slip model. This means that the tsunami
would reach to Camana city, that did not happen, and this isbecause the values obtained for the slip amount on thenorthern part of the fault in the Tsunami waveform inversion
model (for to get the heterogeneous slip model) areoverestimated (Adriano, 2010).

Fig. 10 Measured inundation distances (ITST)In Figure 11 shows a synthetic waveform (tidal meter)
located in the region of the grid D. The peak of the firstwave arrives about 12 minutes and the next largest wave
arrives at 28 min. The maximum wave height is about 7 m(which is consistent with the observation in situ). After 3- 1570 -hours the wave amplitude has been reduced to little morethan 1 m.

73, number 6, p. 907-920.
Adriano, B., 2010. Validation of Tsunami Inundation Modelling
for the June 23, 2001 Peru earthquake. Master paper, Tsukuba
University, Japan.
Goto and Ogawa, 1992. Numerical Method of Tsunami simulation
with the leap-frog scheme. Tohoku University.

Fig.11 Synthetic waveform tsunami from a virtual tidal
station located in the coastline of the flood region.

7. CONCLUSIONSCamana City is well located, but not the coastal resort
in an area that is highly vulnerable to the occurrence of atsunami, which means that in future similar event may occur
as in 2001.
The value of seismic moment Mo = 4.9*1021 Nm
calculated in this work indicates that the earthquake of
Camana 2001 generated small but destructive tsunami.
For a local tsunami, the arrival time of the first wave
will be about 12 minutes, which provides little time forevacuation. However, not always the first wave is the largest.
The run-up (maximum flood height) reached a heightof 7 m on average, implying that some places like the resort,would be potential flood spots.
The results in this paper are a mathematical physicalmodel to some extent validated by field data and evidence.
The relevant authorities should develop plans fordisaster mitigation in the event of an earthquake and tsunami.
The coastal population must learn to be forewarned before
the occurrence of these events.
References
Jiménez, C., Ortega, E. 2008. Cálculo de la Inundación delMaremoto del Callao de 1746. Revista de Investigación deFísica, vol. 11, Nº 1, p. 20-26
Kulikov, E., Rabinovich, A., Thomson, R. 2005. Estimation ofTsunami Risk for the Coasts of Peru and Northern Chile. NaturalHazards vol. 35, p. 185-209.
Papazachos, B., 2004. Global relations between seismic fault
parameters and moment magnitude of Earthquakes. Bulletin of
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Talandier J., 1993. French Polynesia Tsunami Warning Center(CPPT). Natural Hazards and Earth System Sciencies 7, p.
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Smith, W., Sandwell, D. 2006. (ETOPO2v2) 2-minute Gridded
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http://www.ngdc.noaa.gov/mgg/fliers/ 06mgg01.html
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Okal, E., Dengler, L. 2002. Field Survey of the Camaná, Peru
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