joint icpt / twas workshop on seismic sources in central america what is the largest earthquake each...
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Joint ICPT / TWAS Workshop on Seismic Sources in Central America
What is the largest earthquake each can produce ?
Heredia, Costa RicaOctober 30 – November 5, 2011
Geological Studies for Surficial Faults Managua, Nicaragua
Marisol Echaverry L. & Antonio Álvarez C. Instituto Nicaragüense de Estudios Territoriales
Dirección General de GeofísicaDirección de Geología Aplicada
La Femina, 2002
Geological Setting Managua Area
BACKGROUNDS
31.03.1931Falla Estadio Centro Oeste
ManaguaRichter: 5.8Depth: 5Km
02.01.72Los Brasiles
16 Km. W ManaguaRichter: 5.5Mercalli: VI
23.12.1972Tiscapa Fault
Managua Lake Richter : 6.2Depth: 5 Km
Investigation of Active Faulting in Managua, Nicaragua and Vicinity Vice Ministerio de Planificación Urbana, Gobierno de la Republica de Nicaragua.
Woodward- Clyde Consultants. November de 1975.
Trench locationBefore, 80s
Morfological surficial expression
Exploratory trenches cartography
Disruption and
displacement key stratas
Managua Area
Geological Formations
Local Stratigraphy
Aligneaments and Faults
Age and Correlation
Map of Faults, 1975
BACKGROUNDS
DATA BASEDATA BASE
Analysis and integration of consultant reports. 1981 a 2002.Analysis and integration of consultant reports. 1981 a 2002.
Copies of 400 reports for library Copies of 400 reports for library
One hundred of lineal kilometers of trenchesOne hundred of lineal kilometers of trenches
Digitizing maps until 1981 (Brown et al., 1973)Digitizing maps until 1981 (Brown et al., 1973)
Woodward - Clyde Consultants, 1975 and Woodward - Clyde Consultants, 1975 and
Ministerio de la Vivienda y Asentamientos Humanos (MINVAH, Ministerio de la Vivienda y Asentamientos Humanos (MINVAH, 1981)1981)
2002 - THE INETER MAP OF FAULTS
BM / ASDI Proyects, BM / ASDI Proyects, 20012001
Objetives and scope
Find evidence of faults: active or not
Geological zoning of the land
Not build on faults
Guarantee the human life and prevent damages of properties
Inspection of Site Study for Soil Use Requirement
CONTENIDO : Proyecto Geologico Estructural
de las fallas activas en el area de Managua INETER/BANCO MUNDIAL/CEPREDENAC
LEVANTO : Gustavo Altamirano T.
DIBUJO : G. Altamirano Gonzalez
REVISO : Graziella Devoli
0.28 m
0.45
Corte de Falla Tiscapa -Pista Sub UrbanaUbicacion a 100mts al Este de la interseccion al centro de convenciones
Escoria Basaltica
Caida Vertical 0.34 mcaida lateral izquierdabuzamiento 42° NW Falla MayorFalla Tiscapa
(PHaq)
Escoria Basaltica
(Hsf) (PHaq)
(Hsf1 ) 0.70m
(Hsf) 0.6
0.55 m
Cesar Agusto Silva ( pared Sur) en la P ista
(Hfs1)Hsj
0.78 m
0.37 m
Hs0.18 m
Hfs 2
GAT 8-c
(Hs)4
3
2
1
0
0 5 10 15
(Haq)(Haq)
(Hsf1)
Escala IndicadaHoja Topografica San Judas
Pro
fundid
ad e
n m
etr
os
1975. Geological Method
Supervision of local geological studiesfor soil use requirements
2003. Método Geofísico
Inspection and Approval Process of the Study
Faults Map of Managua. March 2002, Escale 1:25,000
Distribución en el tiempo de estudios geológicos de falla local en Managua y alrededores Distribución en el tiempo de estudios geológicos de falla local en Managua y alrededores
Periodo 1990 a 2008. Fuente: Ineter, 2008Periodo 1990 a 2008. Fuente: Ineter, 2008
Estudios geológicos vs Tiempo
1990-2008: 1547 reports: 154.7 lineal Km2003 – 2008: Geological: 489
Geophysical: 32 2009 – 2011: 180 a 200
BOLETIN SISMOLBOLETIN SISMOLÓÓGICOGICO
CONCLUSIONS CONCLUSIONS
Datas about new fault sites, active or not, are available, and others could be Datas about new fault sites, active or not, are available, and others could be aggregates, but limited. No data about Neotectonics and Paleo seismology are aggregates, but limited. No data about Neotectonics and Paleo seismology are being colected.being colected.
know its seismical activity, above all, the most important faults is know its seismical activity, above all, the most important faults is necessary, and study that with no information but densely necessary, and study that with no information but densely inhabited. inhabited.
Could be practical and useful combine these geological studies with geodetics Could be practical and useful combine these geological studies with geodetics studies of deformation for prevention of seismic hazard and risk, for Managua studies of deformation for prevention of seismic hazard and risk, for Managua fault region and its vicinityfault region and its vicinity