Quantifying the geometry and sediment fabric of linear slopes: examples from the Tertiary of Italy (Southern Alps and Gargano Promontory)

The geometries and sediment characteristics of two well-exposed submarine slope successions of ancient carbonate platforms were studied to analyse the relationship between inclinations of linear slopes and sediment fabric. The two examples are an Oligocene platform-to-slope succession exposed on the Brione Mountain in the Southern Alps, and an Eocene slope-to-basin succession exposed on the Saraceno Mountain in the Gargano Promontory. The planar slope of the Brione Mountain outcrop is inclined up to 20-25degrees and consists of fine to coarse sand sized, skeletal packstones and grainstones, and that of the Saraceno Mountain outcrop has a modal angle of 15-22.5degrees, and comprises very fine to coarse sand sized, poorly washed skeletal packstones, grainstones, and rudstones. The good agreement between the inclinations of the linear slope profiles and angles of repose published in the literature implies that these slopes are at or very close to the angle of repose. The general rule that in systems built to the angle of repose, slope angle is directly correlated to sediment fabric, can be applied to linear slopes. (C) 2002 Elsevier Science B.V. All rights reserved.