Field of Science


Fig.1. Watercolour by Josiah Gilbert illustrating the Southern Tyrol landscape (GILBERT & CHURCHILL 1864). This romantic 19th Century image of the Rosengarten Group is one of the watercolours and etchings printed in their travel journal, which details the authors’ "excursions through Tyrol, Carinthia, Carniola, & Friuli in 1861, 1862, & 1863 including a geological chapter, and pictorial illustrations from original drawings on the spot." (from MCKENZIE et al. 2009).

The denomination of the mineral Dolomite refers clearly to the French naturalist Dèodat de Dolomieu (1750-1801), but it was the Italian geologist Giovanni Arduino (1713-1795) that in 1779 reported for the first time a distinct "limestone" with high magnesium content. However Arduino, even recognising the peculiarity, didn't delve into the subject, and so in 1792 the name Dolomite was introduced in the scientific literature, from where it spread trough books for the general public to the mountains from where the mineral was described - the Dolomites.
The true nature and formation of these mountain peaks remained a mystery for the next 200 years. In the 19th Century the Austrian Geological Survey began to carry out the first scientific studies.
Baron Ferdinand F. von Richthofen (1833-1905) in 1860, after carefully mapping and studying the stratigraphical interrelationships in the Dolomites, formulated the coral-reef hypothesis and wrote ''the Schlern is a coral reef, and the entire formation of the 'Schlern Dolomite' has in like manner originated through animal activity".
These words are also more remarkable, considering that only 18 years before Darwin for the first time proposed a convincing explanation how modern reefs and atolls form (DARWIN 1842). But aside the surface of atolls, nothing was known about the deep-sea architecture and structure of a reef, or the surrounding area.

The naturally occurring cross-section in the Dolomites provided a unique possibility. Considering the descriptions and argument of Darwin, Richthofen noted the great difference in elevation between the Schlern and the surrounding landscape (formed of easily erodible volcano-clastic sediments), and that the slopes of the carbonatic buildups are falling steeply on all sides, isolating them from similar masses in the vicinity.

Edmund Mojsisovics von Mojsvar (1833-1905) maintained and developed further the coral-reef hypothesis, mapping the relationships between the single facies, ranging from the lagoon of the atoll to the oceanic basin.

The inclined sediment tongues noted by Richthofen, and described as "Übergussschichten" (icing on the cake, today referred as Clinoforms) represent gravitate mobilised reef detritus, that slip down the slope, forming a reef talus and accumulating around the atoll.

The observations of von Mojsvar, accompanied and documented by illustrations, maps, profiles and the first geological related photographs, firmly established the concept that the structures of the Dolomites were formed originally as isolated carbonate platforms in an open marine environment.

Fig.2. North-south longitudinal cross-section through the Rosengarten-Schlern Mountains (Stratal dip in the background of the Thierser Valley; reproduced from Mojsisovics von Mojsvar, 1879). Although the two mountains are tectonically and orographically separated, the profile illustrates the striking consistency of the total thickness (900 to 1000 m) for the massive Wengen Dolomite (g), suggesting a parallel formation history. The Raibler Schichten (k) caps the Schlernmassiv (from MCKENZIE et al. 2009).

Fig.3. The Rosengarten today as seen from the village of Deutschnofen. Fig.4. The profile of the Rosengarten group in the Dolomites. Overlying a horizontal anisian carbonate platform (Contrin-Formation) is a ladinian reef, displaying a slope with clinoforms (reef and fore-reef facies of the Schlern-Formation) dipping to the basin facies (Buchenstein-Formation).


DARWIN, C. (1842): The Structure and Distribution of Coral Reefs. Smith, Elder and Co., London: 214
GILBERT, J. & CHURCHILL, G.C. (1864): The Dolomite Mountains. Excursions through Tyrol, Carinthia, Carniola, & Friuli in 1861, 1862, & 1863. Longman, Green, Longman, Roberts, & Green, London: 576
MCKENZIE, J.A. & VASCONCELOS, C. (2009): Dolomite Mountains and the origin of the dolomite rock of which they mainly consist: historical developments and new perspectives. Sedimentology 56: 205-219
MOJSISOVICS VON MOJSVAR, E.M. (1879): Die Dolomit-Riffe von Südtirol und Venetien. Beiträge zur Bildungsgeschichte der Alpen. Alfred Hölder, Vienna: 552
SCHLAGER, W. & KEIM, L. (2009): Carbonate platforms in the Dolomites area of the Southern Alps - historic perspectives on progress in sedimentology. Sedimentology 56: 191-204

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