Flinders University
School of Chemistry, Physics and Earth Sciences
Adelaide, SA, 5001
sadr0004@flinders.edu.au

Several rivers enter the inner part of the Persian Gulf, a region with a large freshwater deficit due to extreme evaporation.

Observations of the circulation in two Iranian estuaries, the Bahmanshir River and the Zoreh River, are reported. Current velocity, salinity and water level were measured over a complete tidal cycle during spring tide, using CTD and acoustic current meter instrumentation.

Observed tidal ranges exceed 3 m in both estuaries. Current speeds reach nearly 1 m/s in the Zoreh estuary and exceed 1 m/s in the Bahmanshir estuary.

The data allow a classification of the two estuaries on the basis of fluid dynamics, using the classification diagram of Hansen and Rattray (1966). Both estuaries are found to fall into the “well mixed” category during spring tide. This is mainly due to the tide in the Persian Gulf, which is a co-oscillation tide characterised by an increase of the tidal amplitude from the Strait of Hormuz to the inner end of the Gulf.

Reference:
Hansen, D. V. and M. Rattray jr. (1966) New dimensions in estuary classification. Limnology and Oceanography 11, 319 - 326.

Submitted on January 22, 2003