METAMORPHIC PRESSURE ESTIMATES AND SEDIMENT VOLUMES FOR THE ALPINE OROGENY - AN INDEPENDENT CONTROL ON GEOBAROMETERS

Journal article

Theories which regard the deep erosion (20-30 km) of orogenic belts as an important factor in the thermal development of the continents rely on pressure estimates from metamorphic geobarometers to give an estimate of the depth scale for this process. The imprecision of geobarometers, and the apparent lack of sediments that would result from this amount of erosion, are frequently-made arguments for much smaller erosion depths. The Alps are a well-studied young mountain belt and afford the opportunity to compare overburden masses inferred from geobarometry with sediment masses in the surrounding sedimentary basins. This comparison suggests that metamorphic geobarometry has not significantly overestimated burial depths, and that the average erosion to date has been over 15 km, with a maximum of 25 km or more; it is probable that the total erosion in the belt will eventually average 20-25 km, with a maximum of around 40 km. A significant feature of the sediment distribution is that over 50% of the volume is outside the neighbouring along-strike sedimentary basins. This fact, which accounts for previous low estimates of Alpine sediment volumes, follows from the response of the lithosphere to loading by continental thickening and may be a common feature of post-orogenic sedimentation. © 1981.

Authors: England, P

• Publication status: Published
• Journal: EARTH AND PLANETARY SCIENCE LETTERS
• Volume: 56
• Issue: DEC
• Pages: 387-397
• Publication date: 1981-01-01
• DOI: 10.1016/0012-821X(81)90142-4
• ISSN: 0012-821X
• Language: English