Publication Date:
2022-01-31
Description:
Using offshore geodetic observations, we show that a segment of the North Anatolian Fault in
the central Sea of Marmara is locked and therefore accumulating strain. The strain accumulation
along this fault segment was previously extrapolated from onshore observations or
inferred from the absence of seismicity, but both methods could not distinguish between fully
locked or fully creeping fault behavior. A network of acoustic transponders measured crustal
deformation with mm-precision on the seafloor for 2.5 years and did not detect any significant
fault displacement. Absence of deformation together with sparse seismicity monitored
by ocean bottom seismometers indicates complete fault locking to at least 3 km depth
and presumably into the crystalline basement. The slip-deficit of at least 4m since the last
known rupture in 1766 is equivalent to an earthquake of magnitude 7.1 to 7.4 in the Sea of
Marmara offshore metropolitan Istanbul.
Type:
Article
,
PeerReviewed
Format:
text
Format:
text
Format:
text
Format:
text