Page 6 - Morticelli_et_al2016
P. 6
6 M. GASPARO MORTICELLI ET AL.
Downloaded by [Universita di Palermo] at 02:49 07 January 2016 (e) breccias and calcarenites (BC); they are 1-m-thick At the base, a decametric interval of white-pink, in
intraformational breccias composed of elements of places hazel, Liassic massive dolomites and dolomitic
laminated limestone and stromatolites with a yel- breccias with elements of algal laminites, stromatolites
lowish marly matrix, becoming upwards coarse and loferitic limestone, is considered the proximal
to fine calcarenites with evaporates levels. portion of the Monte Falcone Formation (MFA1).
They are uncomformably overlain by thick mega-con-
(f) very altered greenish basalts (ß). glomerates and breccias with m-thick elements of grey-
white stromatolites, loferitic limestone and algal lami-
4.1.3.3 The Punta Libeccio stratigraphic section. The nites (MFA2). Upper Liassic-Dogger grey limestone
Punta Libeccio stratigraphic section displays the Bas- (Scaturro Formation, PZS) follow upwards above a
sano succession with very low thickness. At Cala buried boundary. At the top of the Punta Troia pro-
Nera (Main Map), grey-whitish to black bituminous montory, the MFA2 are bounded by an iron-encrusted
limestone and dolomitic limestone, bearing algal lami- surface. This hard ground is onlapped by red-green
nites with fenestral porosity, desiccation structures and shales with radiolarians, silicified limestone and spon-
loferitic breccias (MARa), are organized in well-strati- golitic marls (Argilliti di Punta Troia, APT), with 50
fied beds; the thickness is not measureable being at cm-thick layers of breccias, passing gradually from
the bottom and not outcropping. These rocks are over- coarse to fine grey-yellowish calcarenites. The total
lain, throughout a reddish oxide-encrusted surface, by thickness is 20–30 m.
interbedded marls (MA), laminated marly limestone
(CML), and laminated limestone (CL). This lithologic 4.2 Quaternary deposits
interval, here only 10-m thick, is correlated to the
upper portion of the Marettimo Formation (MARb−c) At the base of the steep carbonatic slopes of the north-
outcropping along the Conca succession. The basal eastern coast of the island (Main Map), a continuous
marly layers are very bituminous, decreasing upwards. wedge of alluvial fans occur. Seaward, they show lateral
At the top, tens of meters thick grey-whitish limestone, facies variation into Pleistocene marine deposits lying
with black chert bands and nodules (Scaturro For- discontinuously over the Mesozoic substratum.
mation) are well stratified in centimetric layers.
4.2.1 Continental deposits
4.1.3.4 The Punta Troia stratigraphic section. Along They are mainly grain-supported breccias and mega-
the trail towards the top of the Punta Troia headland breccias, cemented or not, alternating with coarse
(Main Map), the Jurassic–Cretaceous succession of sands with silty matrix, often reddish (DETa). The
the Falcone Unit is outcropping. geometry and texture of these deposits are typical of
alluvial fans with seaward-dipping clynoforms (Figure 5
Figure 5. Composite stratigraphic section showing architecture and geometry relationships between continental and littoral upper
Quaternary deposits. See text for more detail.
