Geology Reference
In-Depth Information
a
b
Figure 1.4
Padan Depression. Location map of oil and gas fields.
a.
Regional faults,
b.
Oil
and gas fields; Fields:
1.
Sergnasno,
2.
Caviaga,
3.
Corneliano,
4.
Ripalta,
5.
Corrazina,
6.
Bordolano,
7.
Cortemaggiore,
8.
Corregio,
9,
Ravenna,
10.
Alphonsine,
11.
Cotignola,
12.
Desana,
13.
Pontenure,
14.
Imola,
15.
Santerno,
16.
Podenzano,
17.
Piadena,
18.
Ravenna-Mare,
19.
Porto-Corsini-Mare.
Ferrara horst. In the Apennine Foredeep, the deposition is continuous dur-
ing the entire Neogene-Quaternary. In the Alpine Foredeep, the Pliocene
is transgressive over the eroded substrate of the Upper cretaceous through
the Lower Miocene, with a Miocene lacuna in between.
Disjunctive tectonics formed the step-block structure of the region.
Two major fault types have been identified. The cross-type mostly longi-
tudinal faults cut the Apennine and Alpine folding. The lengthwise faults
extend parallel to these mountain ranges (see Figure 1.4). Some scien-
tists (Bakirov, Varentsov, Bakirov, 1970; Gortani, 1965; Rocco, Dzhaboli,
1961) believe that the cross-type faults reflect basement blocks, whereas
the lengthwise faults do not penetrate below the sediment cover. The
largest faults reach 100 km in length with the throw of over 4,000 m.
Usually they are found on the north flanks of the local highs making them
downthrown.
The folds in the region are genetically fault-related. They have high
amplitudes; they are asymmetric and faulted. They form individual lin-
ear zones parallel to the Apennines and Alps Mountains. The closer to the
mountains, the stronger is deformation of the local structures; some inter-
vals show the indications of neotectonic nappes (Beka, Vysotsky, 1976;
Vysotsky, Olenin, Vysotsky, 1984; Gortani, 1965).
