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A few scattered outcrops of limestones are present south of Mashhad along the Binalood mountains, most of which are observeable in north of Aman-Abad village. Four stratigraphic sections were measured that thickness varies from 30 to 85 meters. They are mainly composed of limestone with a few horizons of siliciclastic rocks, including sandstone and conglomerate. Abundance of Orbitolina in these rocks, especially Iraqia simplex species, indicates that they are Aptian in age. Petrographic studies of 105 thin sections showed that the Cretaceous sediments in the study area consist of four carbonate and two siliciclastic lithofacies. The carbonate rocks were deposited in a shallow carbonate platform of ramp type, including open marine, shoal, lagoon and beach / tidal flat sub-environments. The siliciclastic rocks were deposited in continental, probably, fluvial depositional system. Field and laboratory studies showed that the sediments are composed of two depositional sequences Ds1 and Ds2 which are bounded by erosional boundaries (SB1). Each sequence begins with lithofacies which indicates the transgression of the sea and makes shallow parasequences after still standing of the sea. Sea level changes during the Lower Cretaceous in the Binalood region are similar to global changes proposed by other researchers, with differences related to local and regional geological event.