Lake Pavin History, geology, biogeochemistry, and sedimentology of a deep meromictic maar lake

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mals, as dragons, and/or marvelous events. They complement

the paleolimnological approach (e.g. Chap. 23 ) and the his-

torical approach (See Chap. 2 ).

3.7.1 The Technical Response: Tunnels

and Canals

The technical response , through tunnels or canals, generated

some engineering marvels (Castellani and Dragoni 1997 ). In

Latium, as early as 400–500 BC, repeated catastrophic lake

surges and overspills during degassing were avoided by

tunnels constructed across crater rims at Albano and Nemi.

At Albano the tunnel excavated in 394 BC is a technical mas-

ter of its time and remained in operation for more than 2300

years, maintaining the lake level at 70 m below the ridge. It

can be considered as the “fi rst prevention device” in risk

management (de Benedetti et al. 2008 ). At Nemi a similar

antique tunnel was re-used in the 1930s to lower the lake

level, suggesting a similar lake overspill threat around Vth

BC. The Laachersee tunnel in Eifel, dated around 1 100 AD,

has a construction similar with the previous ones and serves

the same function (Leidinger 2007 ). Other tunnels and a

canal have been constructed at Averno during Antiquity, but

their exact function is debated. Lake Monticchio outlet has

also been connected to the nearby river by a canal excavated

through the crater rim and several Eifel maars have canals

(Scharf et Björk 1992 ). The degassing pipe installed success-

fully at Nyos after the 1986 event follows this remediation

approach (Halbwachs et al. 2004 ).

3.7.2 Lake Cults and Other Religious

Responses

The pre-Christian worshipping response has been important in

Italy during Antiquity. Long before the birth of Rome, in the

VIIth century BC, there were major sanctuaries in the Lake

Nemi lake crater, dedicated to Diana Nemorensis , and on the

rim between Nemi and Albano craters another temple was

dedicated to Jupiter Latiaris (Carandini 1997 ). There, the 3 day

Feriae Latinae was celebrated each year by all Latium cities

and sacrifi ces were made to the master of thunders and light-

ning. Considering the possible occurrence of lake disorders at

Nemi, the famous gigantic Nemi ships built by Emperor

Caligula could also have had a cultual function. The Averno-

Cumeo site, presented as an entrance to the Hades , was also an

early sanctuary and place of the Sibyl divination, which lasted

from the Greek colonization of Italy to Imperial Rome. On the

shores of Monticchio Piccolo Lake antique ex-votos have been

found in San Michele grotto. Celtic archeological artifacts have

been found on the shores of some Eifel lakes and their relation

to lake cult could be checked. At Pavin pre-Christian cults and

offerings are mentioned by some XIXth century authors, pos-

sibly described by Gregorius and present in the Fairies Garden

legend; they remain to be found by archeological exploration.

Fig. 3.6 Christian protection against Pavin misbehavior. ( a ) Santa
Martha from Tarascon present at Besse Saint André church
(1670) (Author's photograph). The Provence saint is a major sau-
roctonous – dragon-killer saint. ( b ). The Vassivière mountain pilgrim-
age in 1900 (Jaloustre 1910 ) (BCU library, Clermont-Ferrand). Its

modern tradition started with the June 1547 miracle event that occurred

below Pavin outlet, 1.5 km from here. This site has probably been an

antique pagan cult (Jaloustre 1910 ), possibly described by Gregorius of

Tours ( 600 AD )

M. Meybeck