Colluvium specific geological setting. Alluvium is sand, clay, or other similar detrital material deposited by running water. The distinction between colluvium and alluvium relates to the involvement of running water. Alluvium specifically refers to the geomorphic processes involved with flowing water and so alluvium is generally fine-grained clay and silt material that has the capacity to be entrained in water currents and eventually deposited. For these same reasons, alluvium is also generally well sorted material while colluvium is not. Colluvium Colluvium (also colluvial material or colluvial soil) is a general name for loose, unconsolidated sediments that have been deposited at the
Rock Sand to his best position of second on the list of leading sires. On his four-year-old debut, Rock Sand ran against Sceptre again in June over the Derby course and distance in the Coronation Cup, a race which also featured the first meeting between Rock Sand and his contemporary Zinfandel, a colt whose engagements in the previous year's classics had been rendered void by the death of his owner Colonel Harry McCalmont. Zinfandel won easily from Sceptre, with Rock Sand third. Rock Sand avoided Zinfandel for the remainder of the season and was unbeaten in his remaining five races. He won