Skip to Main Content
Book Chapter

Palaeoseismology of the North Anatolian Fault near the Marmara Sea: implications for fault segmentation and seismic hazard

By
Thomas Rockwell
Thomas Rockwell
Geological Sciences, San Diego State University, San Diego, CA 92182, USA
Search for other works by this author on:
Daniel Ragona
Daniel Ragona
Geological Sciences, San Diego State University, San Diego, CA 92182, USA
Search for other works by this author on:
Gordon Seitz
Gordon Seitz
Geological Sciences, San Diego State University, San Diego, CA 92182, USA
Search for other works by this author on:
Rob Langridge
Rob Langridge
Institute of Geological and Nuclear Sciences, PO Box 30-368, Lower Hutt, New Zealand
Search for other works by this author on:
M. Ersen Aksoy
M. Ersen Aksoy
Eurasia Institute of Earth Sciences, Istanbul Technical University, Maslak, Istanbul, Turkey
Search for other works by this author on:
Gülsen Ucarkus
Gülsen Ucarkus
Eurasia Institute of Earth Sciences, Istanbul Technical University, Maslak, Istanbul, Turkey
Search for other works by this author on:
Matthieu Ferry
Matthieu Ferry
Universidade de Évora, Centro de Geofisica de Évora, Rua Romão Ramalho 59, 7002-554 Évora, PortugalInstitut de Physique de Globe, 5 rue René Descartes, F-67084 Strasbourg Cedex, France
Search for other works by this author on:
Aron J. Meltzner
Aron J. Meltzner
Tectonics Observatory, California Institute of Technology, Pasadena, CA 91125, USA
Search for other works by this author on:
Yann Klinger
Yann Klinger
Laboratoire de Tectonique, Institut de Physique du Globe, 4 place Jussieu, 75005, Paris, France
Search for other works by this author on:
Mustapha Meghraoui
Mustapha Meghraoui
Institut de Physique de Globe, 5 rue René Descartes, F-67084 Strasbourg Cedex, France
Search for other works by this author on:
Dilek Satir
Dilek Satir
Eurasia Institute of Earth Sciences, Istanbul Technical University, Maslak, Istanbul, Turkey
Search for other works by this author on:
Aykut Barka
Aykut Barka
Eurasia Institute of Earth Sciences, Istanbul Technical University, Maslak, Istanbul, Turkey

Deceased.

Search for other works by this author on:
Burcak Akbalik
Burcak Akbalik
Eurasia Institute of Earth Sciences, Istanbul Technical University, Maslak, Istanbul, Turkey
Search for other works by this author on:
Published:
January 01, 2009

Abstract

We conducted palaeoseismic studies along the North Anatolian fault both east and west of the Marmara Sea to evaluate its recent surface rupture history in relation to the well-documented historical record of earthquakes in the region, and to assess the hazard of this major fault to the city of Istanbul, one of the largest cities in the Middle East. Across the 1912 rupture of the Ganos strand of the North Anatolian fault west of the Marmara Sea, we excavated 26 trenches to resolve slip and constrain the earthquake history on a channel–fan complex that crosses the fault at a high angle. A distinctive, well-sorted fine sand channel that served as a marker unit was exposed in 21 trenches totaling over 300 m in length. Isopach mapping shows that the sand is channelized north of the fault, and flowed as an overflow fan complex across a broad fault scarp to the south. Realignment of the feeder channel thalweg to the fan apex required about 9±1 m of reconstruction. Study of the rupture history in several exposures demonstrates that this displacement occurred as two large events. Analysis of radiocarbon dates places the age of the sand channel as post ad 1655, so we attribute the two surface ruptures to the large regional earthquakes of 1766 and 1912. If each was similar in size, then about 4–5 m of slip can be attributed to each event, consistent with that reported for 1912 farther east. We also found evidence for two additional surface ruptures after about ad 900, which probably correspond to the large regional earthquakes of 1063 and 1344 (or 1354). These observations suggest fairly periodic occurrence of large earthquakes (RI=c. 283±113 years) for the past millennium, and a rate of c. 16 mm/a if all events experienced similar slip.

We excavated six trenches at two sites along the 1999 Izmit rupture to study the past earthquake history along that segment of the North Anatolian fault. One site, located in the township of Köseköy east of Izmit, revealed evidence for three surface ruptures (including 1999) during the past 400 years. The other trench was sited in an Ottoman canal that was excavated (but never completed) in 1591. There is evidence for three large surface rupturing events in the upper 2 m of alluvial fill within the canal at that site, located only a few kilometres from the Köseköy site. One of the past events is almost certainly the large earthquake of 1719, for which historical descriptions of damage are nearly identical to that of 1999. Other earthquakes that could plausibly be attributed to the other recognized rupture of the Izmit segment are the 1754, 1878 or 1894 events, all of which produced damage in the region and for which the source faults are poorly known. Our palaeoseismic observations suggest that the Izmit segment of the North Anatolia fault ruptures every one and a half centuries or so, consistent with the historical record for the region, although the time between ruptures may be as short as 35 years if 1754 broke the Izmit segment.

Release of about 4 m of seismic slip both west and east of the Marmara Sea this past century (1912, 1999) support the contention that Istanbul is at high risk from a pending large earthquake. In that historical records suggest that the last large central Marmara Sea event occurred in 1766, there may be a similar 4 m of accumulated strain across the Marmara basin segment of the North Anatolian fault.

You do not currently have access to this article.
Don't already have an account? Register

Figures & Tables

Contents

Geological Society, London, Special Publications

Palaeoseismology: Historical and Prehistorical Records of Earthquake Ground Effects for Seismic Hazard Assessment

K. Reicherter
K. Reicherter
RWTH Aachen University, Germany
Search for other works by this author on:
A. M. Michetti
A. M. Michetti
Università dell’Insubria, Italy
Search for other works by this author on:
P. G. Silva
P. G. Silva
Universidad de Salamanca, Spain
Search for other works by this author on:
The Geological Society of London
Volume
316
ISBN electronic:
9781862395640
Publication date:
January 01, 2009

GeoRef

References

Related

A comprehensive resource of eBooks for researchers in the Earth Sciences

This Feature Is Available To Subscribers Only

Sign In or Create an Account

This PDF is available to Subscribers Only

View Article Abstract & Purchase Options

For full access to this pdf, sign in to an existing account, or purchase an annual subscription.

Subscribe Now