Roubach et al., 2014: PREPARATION OF TURTLE FOSSIL
INTRODUCTION
comprises more than 50 well preserved
monogenetic cones and some others with both
explosive and non-explosive activity phases
Paleontological studies contribute to identify
(detailed references available in Gómez de
and
determine
species
evolution
and
Soler et al. 2012). It is a volcano maar-type
chronology, as well as the interactions with
site, formed by phreatomagmatic explosions.
other species and with their environment.
These explosions resulted from brief, near-
Therefore, good conservation of fossils is
surface magma/water interactions occurring
crucial for their manipulation and/or exhibition.
during the ascent of magma towards the
However, specimens are often highly fragile
surface which in turn led to violent explosions.
when discovered and such fossils often require
The presence of groundwater led to the
a certain level of maintenance to give them
development of a lake inside the crater. The
strength and shock resilience. In this work, the
sedimentary infill is characterized by typical
preparation processes carried out, both in situ
vertical stratigraphic succession in maars
and in laboratory, on one case of turtle fossil
(Pirrung et al., 2003; Lindner et al., 2006).
from the Pliocene site of Camp dels Ninots is
Syn-/post-eruptive
wall
rock
debris
and
presented.
pyroclastic breccias characterize the bottom
The Camp dels Ninots maar site is located in
deposits and are followed by a fining-upwards
Caldes de Malavella, Girona, NE Spain. Its
sequence of lacustrine muds with coarse layers
coordinates UTM31N (ETRS89) are 483202 E
and final shallow lake deposits (Figure 2). The
and 4631454 N (Figure 1A). The Camp dels
site has been recently classified as a Konservat-
Ninots volcano is a part of the Catalan Volcanic
Lagerstätte (Gómez de Soler et al., 2012), and
Complex which took place between 14 Ma and
the
stratigraphy
shows
a
lacustrine
10 Ka in NE Spain (Gómez de Soler et al.,
sedimentation in a maar, which are ideal
2012). The basaltic monogenetic volcanic zone
conditions for the preservation of fossils.
Figure 1: Location of Camp dels Ninots site in Spain and north east Catalunya (A) and map of the Can Argilera sector (B).
39 Journal of Paleontological Techniques