Wrinkled, folded, ropy surface of the "Lava dei Dammusi", erupted in 1614-1624 on the northern flank of Etna. This is one of the few lava fields on this volcano that is largely pahoehoe, and it is enormous. The "grainy" aspect of the lava, seen in the right image (as well as in a number of those below) is due to the presence of considerable quantities of plagioclase phenocrysts

The 1614-1624 lava field ("Lava dei Dammusi"), 24 July 2003

The most voluminous and longest-lasting flank eruption of Etna during the historical period began in 1614 in the upper portion of the Northeast Rift and lasted for ten years, until 1624. The volume of lava emitted during that event is estimated at 1-2 cubic kilometers (compare this to the 0.02 and 0.03 cubic kilometers of lava of the 2001 and 2002-2003 eruptions, respectively), a volume similar to that emitted during the first twenty years of the ongoing Pu'u 'O'o eruption of Kilauea volcano in Hawaii. Seen on the geological map of Etna, the 1614-1624 lava flow-field is seen to cover a large fan-shaped area on the northern flank of the volcano; however, none of the numerous distal lava lobes extended into the inhabited and cultivated areas on the lower northern flank, and the eruption is not known to have caused any significant damage. The area of the lava field is given by Romano and Sturiale (1982) as 21 km² with a maximum flow length of 6.5 km.

Maps of the 1614-1624 lava field. Left map shows 1614-1624 lava flow-field in red, and other lava flows erupted between 1600 and 2003 in pink color. The flow maps are draped on a Landsat image taken on 13 July 2001 and processed by Eurimage, the copyright being of the European Space Agency. Extent of the 1614-1624 lava flow-field is based on the geological map of Etna (Romano, 1979). The map at right is taken from Guest et al. (1984) and shows volcanologically relevant structures on the 1614-1624 lava flow-field. Note that the extent of the flow-field in this map differs slightly from the one in the map at left

Yet, besides its sheer size, the lava field of that eruption is one of the most interesting among the hundreds of distinct lava fields on Etna. Firstly, it is largely composed of pahoehoe lava (a Hawaiian word meaning "one can walk barefoot on it", applied to lavas with a smooth, wrinkled, or ropy, surface), and this type of lava surface is quite rare at Etna. Secondly, the lava field presents a variety of peculiar morphological features that give indications about the styles of lava transport and emplacement during that eruption (these have been the subject of a publication by Guest et al., 1984). Thirdly, like all lavas erupted at Etna between 1600 and 1669, these lavas are rich in large phenocrysts of plagioclase, which have led to the Sicilian name "cicirara" - roughly translated as "pea lavas" (see photo below). And last but least, the lava field contains several lava caves, the largest of which are the Grotta del Gelo and the Grotta dei Lamponi. These caves are nothing else than lava tubes, through which lava was transported at low heat loss from the eruptive vents to areas further downslope, in some cases extending over distances of several kilometers.
The photographs below were taken during a field campaign with scientists of the INGV Roma and from various universities in Italy on 24 July 2003, some of these persons can be seen in a few of the images. Most of the photographs are not captioned, since they talk for themselves. The "Lava dei Dammusi" (the local name for the 1614-1624 pahoehoe lava field) is one of Nature's grand masterpieces.

"Cicirara", a Sicilian word that can be loosely translated as "pea lava", is applied to lavas at Etna that are rich in sizeable plagioclase phenocrysts. Such lavas have been produced repeatedly during the geological history of the volcano and seem to reflect a set of conditions of magma supply, storage and eruption different from the present conditions. The last time that Etna produced "cicirara" was in the 17th century. Not in just one eruption, but all eruptions that occurred from 1600 until 1669, no matter on which side of the volcano they occurred, and no matter how explosive they were. This image shows a typical chunk of "cicirara", erupted in 1610 on Etna's southwestern flank (coin is 2.2 cm in diameter)

References:

Guest JE, Wood C, Greeley R (1984) Lava tubes, terraces and megatumuli on the 1614-24 pahoehoe lava flow field, Mount Etna, Sicily. Bulletin Volcanologique 47: 635-648

Romano R (editor) (1979) Geological map of Mt. Etna. S.EL.CA. Firenze (distributed with volume 23 of the Memorie della Società Geologica Italiana, 1982, but out of print long since!)

Romano R, Sturiale C (1982) The historical eruptions of Mt. Etna (Volcanological data). Memorie della Società Geologica Italiana 23: 75-97

The landscape around the Passo dei Dammusi, a spot at about 1700 m elevation on the northern flank of Etna, looking west. The dark lava in the background and the brownish lava in the foreground both belong to the enormous 1614-1624 lava field

Page set up on 11 June 2003, last modified on 11 August 2003