As an important component of natural ecosystems, the identification of soil characteristics is necessary for sustainable land use management. On the other hand, soils have been extensively used as continental archives of climate change. Silt-enriched soils and sediments have discontinuously covered the regolithic pediments, meta-sedimentary rock pediments, terraces of Torogh River and some parts of piedmont plain of Binaloud zone in southern Mashhad . Despite the importance of the silty deposits for Quaternary landscape evolution and land use management, they have received little attention by geologists and soil scientists. The objectives of this study were i) to determine the distribution, characteristics, nature and provenance of the silty sediments of southern Mashhad, ii) to study the morphology, mineralogy and micromorphology of silty soils and other soils and sediments to make a qualitative paleoclimate interpretation and iii) to conduct a pedochronostratigraphical investigation on silty sediments from southern Mashhad and loess deposits from Kalat-e Naderi. In this regard, the particle size distribution, microtexture of quartz grains, geochemical properties, mineralogy and micromorphology of silty deposits and associated soils and sediments were studied. The infrared stimulating luminescence (IRSL) dating of Robat-e Khakestari, Tappeh salam and Deh Gheybi sections (a) and (b) from southern Mashhad and Kalat-e Naderi (a) and (b) sections from Kalt-e Naderi area were determined. Based on particle size distribution, abrupt particle size difference between silty deposits and underlying materials, the shape and microtexture of quartz grains, chemical and geochemical data and geochemical homogeneity of silty deposits from different landforms and geomorphic position, silty sediments of the study area seem to be wind-blown in origin and are, therefore, Iran as well as those in arid parts of the world is an indication of similarity in Tertiary paleoenvironmental conditions of these areas. 2) A relatively high amount of palygorskite, detected easily by XRD in Bk and By horizons, appears to be the result of illuviation of palygorskite associated with carbonates or gypsum. 3) A lesser amount of palygorskite was detected by TEM in the red Btk horizons (OIS5 paleosols) in loess sections. The existence of carbonate nodules covered by clay and silt coating indicates a moist condition after carbonate illuviation and an unstable environment for palygorskite during the last interglacial period. 4) A very low quantity of detrital palygorskite was found in unaltered loess deposits originated from gypsiferous marls. The dose rate ranges from 3.65 to 4.28 Gy/ka. Equivalent dose values range from 45.7±2.1 to