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H. Koral

Publications and source records attributed to H. Koral.

2 recordsLinked to original sources

Geomorphological, depositional, and foraminiferal indicators of late Quaternary tectonic uplift in Iskenderun Bay, Turkey

Iskenderun Bay is a major shallow embayment in the eastern part of the Mediterranean Sea, where the African and Anatolian Plates converge. This tectonically active basin was investigated for oceanographic, sedimentological, geochemical, and foraminiferal parameters. On the basis of the data acquired, the distribution of living and fossil foraminifera in 284 grab and 54 gravity core samples was determined, the basin floor bathymetry of the bay constructed, radiocarbon ages of sediments and fossils ascertained, and depositional environments reconstructed. It has been discovered that for the last 13.5 k.y., water masses were stratified and sedimentation was discontinuous within the basin, which is characterized by irregular sea bottom morphology. The sedimentation rate was very slow, varying in time and space from 0 to 0.012 cm yr −1 . The foraminiferal distributions were spatially varied and discontinuous and indicate a reversal from deep to shallow marine conditions in the cores. These irregularities were attributed to active tectonics in the bay and a major tectonic uplift of the bay since the late Pleistocene.

Iskenderun Bay

Intra-basinal water movements induced by faulting: The August 17, 1999, Golcuk (Izmit Bay) earthquake (M(W) = 7.4)

A strong earthquake (M(w) = 7.4) occurred near the town of Golcuk, Izmit Bay, Western Turkey, at 00:01 GMT on August 17, 1999. Izmit Bay is a E-W trending pull-apart basin with a surface area of about 300 km2 along the North Anatolian Fault Zone (NAF), in the eastern extension of the Sea of Marmara. The earthquake was caused by a westerly movement of the Anatolian plate along NAF and was accompanied by isolated, chaotic water movements along the northern and southern shores of the bay. At localities along the shoreline a sudden drop in sea level, and a subsequent rise was prominent. The mode of observed sea-level movements rules out the occurrence of a basin-wide tsunami, sensu stricto. Instead, the water movements are attributed to localized sudden dip-slip movements of fault blocks in this pull-apart basin. (C) 2000 Elsevier Science B.V.

Marine Geology