Chapter 38 - The Romanian Carpathians: glacial landforms prior to the Last Glacial Maximum

Abstract

In the Romanian Carpathians, especially in the Southern Carpathians, the Transylvanian Alps, and in the highest parts of the Eastern Carpathians, the glacial relief is the one that imprints the dominant note of the geomorphological landscape. If in the last three decades of the 19th century, the period of the first ideas on the existence of the Quaternary glaciation traces in the Romanian Carpathians, the controversies were characteristic, today no one doubts its existence. In addition, a chronological clarification based on the absolute ages, using terrestrial cosmogenic radionuclide dating (TCN), allows the differentiation in time of the glaciation evolution. At various times, and from author to author—beginning with Emmanuel de Martonne in 1900—the chronological differentiation oscillated between three glacial phases, Mindel, Riss, and Würm, two glacial phases; one of the valley glaciers (Thalgletscher) and another restricted to the cirque glaciers (Kahrgletscher); and a single glacial phase, Würm, with several stadials. So far, only the TCN-based ages obtained for the highest mountain range in the Eastern Carpathians, the Rodna Mountains (Pietrosu Peak, 2305m) indicate a prior-LGM glacial stage. Three sampled boulders situated in Pietroasa Valley, between 1000 and 800m yielded pre-LGM exposure ages, between 37.2 and 33.3ka. A 4-km long moraine descending from 1250 to 850m revealed in its lower part ages between 37.2±3.4 and 26.6±2.4ka. For this stage, ELA was between 1203 and 1256m.