introduction in general, loess sediments are one of the most widespread forms of aeolian sediments. during the past few decades, loess stratigraphy studies played key role in the investigation about global climate changes. these sediments are usually yellowish in color and silt makes 70 to 90 percent of its volume. in iran, loesses outcrop are often in northeast part of south caspian sea. the p...

wave prediction is useful for safety and effective management of vessel navigation or construction of offshore structures. since human activity mainly takes place in nearshore regions, accurate wave prediction is necessary there. however, nearshore waves are not easy to predict compared with ocean waves, because not only the waves but also the wind, which is the energy source of the waves, chan...

introduction extreme floods, hyperconcentrated and debris flows are common natural hazards in the basins which located in the northern slops of alborz mountain range (iranian north system). flood occurrence in golestan national park in 2001, 2002 and 2005( hosseinzadeh and jahadi toroghi 2012), yearly flash floods in masuleh catchment( rezaei, 2009), large flood in neka basin in 1999(poorahmad ...

1. introduction current statistical methods may be unable to accurately predict recurrence intervals of rare, large magnitude floods. the usual procedure involves extrapolation from gauged hydrological records documenting 30–40 year records of observed (normally small) floods to the estimation of the quantifies and recurrence intervals of very large, rare floods. this conventional approaches be...