The polygenetic Albano maar is themost recent centre of the Colli Albani volcano, located just few kilometres to the south-east of Roma. Presently the maar hosts a 167.5mdeep crater lake, the deepest in Europe. Themaar is to be considered quiescent, as phreatic activity is documented throughout the Holocene. This paper illustrates the close relationships between the activity of themaar and the history of settlement in the Roman region as recorded in the geology, archaeology, history and legends of the area. Severe fluctuations of the groundwater table and catastrophic overflows of the Lake Albano fromthemaar rimhad occurred prior to and after the early prehistoric settlements dated in themaar area at the Eneolithic times (ca. III millenniumB.C.). Repeated lahars occurred along the northwestern slope of themaar filling in the paleodrainage network and forming a vast plain. Paleohydraulic analyses on fluvial and lahar deposits originated fromthe Holocene phreatic activity of the Albanomaar indicate sediment–water flows in excess of hundreds of cubic metres per second. Absolute age determinations of the paleosoil underlying one of the most recent deposits of the lahar succession at 5800±100 yr B.P. (14C CAL) are in perfect agreement with the age of the overlying Eneolithic age settlements. The last catastrophic overflow is described in the Roman literature as a consequence of the anger of Poseidon against the Romans in 398 B.C. for their war against the Etruscans. In 394 B.C. the Romans decided to prevent the repetition of such events by the excavation through the maar craterwall of a 1.5 km long drain tunnel, which is still operational, keeping the lake 70mbelowthe lowest point of themaar rim. This tunnel drain may be regarded as the first prevention device for volcanic hazard in history and shows an unprecedented development of the engineering technology under the pressure of hazard perception. The surprising and still largely unknownresults of this study are very important to redefine the hazard of the Roman region.
DE BENEDETTI, A., Funiciello, R., Giordano, G., Diano, G., Caprilli, E. (2008). Volcanology history and myths of the Albano maar. JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH, Spec. Vol., 176, 387-406. doi: 10.1016/j.jvolgeores.2008.04 [10.1016/j.jvolgeores.2008.04].
Volcanology history and myths of the Albano maar.
FUNICIELLO, Renato;GIORDANO, Guido;
2008-01-01
Abstract
The polygenetic Albano maar is themost recent centre of the Colli Albani volcano, located just few kilometres to the south-east of Roma. Presently the maar hosts a 167.5mdeep crater lake, the deepest in Europe. Themaar is to be considered quiescent, as phreatic activity is documented throughout the Holocene. This paper illustrates the close relationships between the activity of themaar and the history of settlement in the Roman region as recorded in the geology, archaeology, history and legends of the area. Severe fluctuations of the groundwater table and catastrophic overflows of the Lake Albano fromthemaar rimhad occurred prior to and after the early prehistoric settlements dated in themaar area at the Eneolithic times (ca. III millenniumB.C.). Repeated lahars occurred along the northwestern slope of themaar filling in the paleodrainage network and forming a vast plain. Paleohydraulic analyses on fluvial and lahar deposits originated fromthe Holocene phreatic activity of the Albanomaar indicate sediment–water flows in excess of hundreds of cubic metres per second. Absolute age determinations of the paleosoil underlying one of the most recent deposits of the lahar succession at 5800±100 yr B.P. (14C CAL) are in perfect agreement with the age of the overlying Eneolithic age settlements. The last catastrophic overflow is described in the Roman literature as a consequence of the anger of Poseidon against the Romans in 398 B.C. for their war against the Etruscans. In 394 B.C. the Romans decided to prevent the repetition of such events by the excavation through the maar craterwall of a 1.5 km long drain tunnel, which is still operational, keeping the lake 70mbelowthe lowest point of themaar rim. This tunnel drain may be regarded as the first prevention device for volcanic hazard in history and shows an unprecedented development of the engineering technology under the pressure of hazard perception. The surprising and still largely unknownresults of this study are very important to redefine the hazard of the Roman region.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
