Terra Rossa in the Mediterranean Region: Parent Materials, Composition and Origin

Thr red colour of many of the soils in the Mediterranean region was the main reason that in the past the broad term “Red Mediterranean soils”, occasionally “terra rossa”, became quite a common indication for all soils in the region (YAALON, 1997). BRESSON (1993) stated that Red Mediterranean soils resulted from a bisiallitic type of weathering with the release of high amounts of iron oxides closely bound to clay minerals. According to FEDOROFF (1997), the bisiallitic type of weathering is not a specific characteristic of Red Mediterranean soils. He also stated that the concept of clay illuviation is not yet unanimously accepted as a leading soil forming process in Red Mediterranean soils. The colour of the B horizon in Red Mediterranean Geologia Croatica 56/1 83–100 23 Figs. 6 Tabs. ZAGREB 2003