Unit:
Κατεύθυνση Πρόληψη και Διαχείριση των Φυσικών ΚαταστροφώνLibrary of the School of Science
Author:
Παλληκαράκης Άγγελος
Supervisors info:
Καθηγητής Μιγκίρος Γεώργιος (Επιβλέπων), Επίκουρος Καθηγητής Παπανικολάου Ιωάννης, Αναπληρώτρια Καθηγήτρια Τριανταφύλλου Μαρία
Original Title:
Study of an active fault in the Corinth canal, through paleoenvironmental interpretations and borehole data. Implications for seismic hazard
Summary:
A fault that intersects the Corinth canal has been studied in detail, based
on several boreholes that were recovered from the hangingwall and the footwall
of the fault. Lithostratigraphic units were described within these boreholes.
Due to the lateral stratigraphic variations that were encountered, it was
difficult to determine the accumulative displacement, as well as the slip rate
of the fault. In order to overcome this problem micropaleontological analysis
was performed.
Foraminiferal assemblages were picked from approximately 100 samples from
boreholes 3 and 7 from the footwall and the hangingwall respectively. Species
were identified and grouped into seven subcategories. Through them, the
paleoenvironment was estimated within the boreholes and it was feasible to
correlate horizons of borehole 3 with borehole 7. A colony of Cladocora corals
that has been found in situ was used in order to estimate vertical offset
between these two boreholes Taking under consideration the known uplift rate
for the Isthmus and global glacioeustatic sea level curve relative dates for
these layers could be estimated.. Afterwards according to these dates and the
measured fault’s offset, the throw rate of the fault was estimated.
Using empirical relationships concerning fault’s geometrical features and the
estimated throw rate for a certain period of time, the seismic hazard posed
from this fault has been assessed. Moreover, the seismic hazard over the entire
Corinth canal posed from the neighboring major active faults was also assessed.
The same procedure was repeated for other significant faults that influence the
area. Loutraki, Kechries, Agios Vasilios and South Alkyonides faults system
were examined in detail in order to determine how hazardous are for the area.
For these faults earthquake recurrence was estimated using the throw rate that
has already been calculated. Geological formations can amplify or lessen the
expected intensity from an earthquake. As a result seismic hazard maps from
geological data were compiled showing expected seismic intensities in the area.
Main subject category:
Natural disasters
Other subject categories:
Structural geology
Earthquakes
Paleontology
Keywords:
Isthmus, Saronic, Seismic hazard, Isthmia-Kalamaki, Paleoenvironment
Number of index pages:
114-118
