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ABSTRACT A hydrogeological research project was conducted in the arid crystalline province of the Southern Sinai. To gain a better understanding of regional groundwater flow patterns, Landsat images as well as air photos were used. Three main flow systems were investigated: (1) The flow system occurring along longitudinal regional crustal fractures with the direction parallel to the Gulf of Elat Rift; this system captures the flow in the main wadi beds draining eastwards. (2) The flow system found in shallow fractured rocks, capturing the flow in small tributaries in the upper part of the drainage basin. (3) The system of dikes governing the flow regime in wadi beds draining westwards. The preliminary estimate of the recharge into the fractured crystalline aquifers and the interconnected gravel bed aquifers is in the order of magnitude of 10–15% of the total precipitation. 相似文献
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Abstract A composite model for real time forecasting of flash floods in the Ayalon stream in central Israel has been constructed. The model is composed of four kinds of sub-models: an autoregressive model for discharges at upstream stations on the two major tributaries; a travel-time model for the flow from these stations to the downstream station located on the main stem of the stream; a time-area concentration curve for subwatershed drainage between the upstream and downstream stations; and a recession curve for the downstream station. The model incorporates an adaptive mechanism for continuous correction of forecast errors. This mechanism is calibrated during an initial period of operation, and is subsequently operated throughout a flow event. The model issues simultaneous forecasts for seven lead times ranging from 0.5 to 3.5 h. This provides a proper input for a flood warning system which is required for safe operation of a major highway running along the banks of a torrent stream in the metropolitan area of Tel-Aviv. 相似文献
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