• This paper presents a geological interpretation of the CROP-04 reflection seismic line based on a 10 sec TWT reprocessed stack section. The achieved major results may be synthesized in the following points: 1) In the western part of the line, a well-structured reflective unit rising from 7-8 sec TWT in correspondence to the Tyrrhenian coast to 4-5 sec TWT in correspondence to Monte Marzano fixes the Apennine sole thrust at a depth exceeding 8 sec TWT, i.e. at a depth or at least 20 kilometers. This depth is independent from the geological attribution of the deep-seated reflective unit since it depends only on the climbing geometry of the reflectors that implies displacement in the hangingwall of a contractional fault. 2) The top of the Apulia carbonates rises from about 5 sec TWT in correspondence to the Tyrrhenian coast to less than 2 sec TWT in correspondence to the crest of the duplex system, where it has been reached by the San Gregorio 1 well, and subsequently deepens towards the NE reaching about 4 sec TWT at the foot of the thrustand-fold cascade featuring the outer flank of the buried antiform. The space between the crest of the antiform and the sole thrust may be entirely filled with imbricates of sedimentary rocks or with sedimentary rocks and crystalline rocks derived from the Apulia basement. The geometry of the aforementioned deep-seated reflective unit suggests a thin-skin tectonic style with no basement involvement. The duplex internal architecture appears to be featured by two major thrust sheets, both lying on top of long thrust flats. This structural architecture agrees with other geological data indicating a minimum cumulative shortening of the duplex system of 90-100 kilometers after the early Pliocene, i.e. after the transport of the allochthonous sheets on the western margin of the Apulia Platform. 3) Well-organized reflectors dubitatively attributed to the lower crust of Apulia have been recognized at 9-10 10 sec TWT in correspondence to the front of the mountain chain. The CROP-04 line cannot provide information on the extent of this reflective unit the 10 sec TWT of time record of the re-processed stack are insufficient for this purpose. 4) As concerns the backstop of the orogenic system, the CROP-04 profile indicates that it must be located somewhere in the Tyrrhenian Sea, west of the line termination. Also the trailing edge of the Apuliacarbonate duplex system must be searches in the offshore west of the line termination

Geological interpretation of the CROP-04 seismic line (Southern Apennines, Italy)

PATACCA, ETTA;SCANDONE, PAOLO
2007

Abstract

• This paper presents a geological interpretation of the CROP-04 reflection seismic line based on a 10 sec TWT reprocessed stack section. The achieved major results may be synthesized in the following points: 1) In the western part of the line, a well-structured reflective unit rising from 7-8 sec TWT in correspondence to the Tyrrhenian coast to 4-5 sec TWT in correspondence to Monte Marzano fixes the Apennine sole thrust at a depth exceeding 8 sec TWT, i.e. at a depth or at least 20 kilometers. This depth is independent from the geological attribution of the deep-seated reflective unit since it depends only on the climbing geometry of the reflectors that implies displacement in the hangingwall of a contractional fault. 2) The top of the Apulia carbonates rises from about 5 sec TWT in correspondence to the Tyrrhenian coast to less than 2 sec TWT in correspondence to the crest of the duplex system, where it has been reached by the San Gregorio 1 well, and subsequently deepens towards the NE reaching about 4 sec TWT at the foot of the thrustand-fold cascade featuring the outer flank of the buried antiform. The space between the crest of the antiform and the sole thrust may be entirely filled with imbricates of sedimentary rocks or with sedimentary rocks and crystalline rocks derived from the Apulia basement. The geometry of the aforementioned deep-seated reflective unit suggests a thin-skin tectonic style with no basement involvement. The duplex internal architecture appears to be featured by two major thrust sheets, both lying on top of long thrust flats. This structural architecture agrees with other geological data indicating a minimum cumulative shortening of the duplex system of 90-100 kilometers after the early Pliocene, i.e. after the transport of the allochthonous sheets on the western margin of the Apulia Platform. 3) Well-organized reflectors dubitatively attributed to the lower crust of Apulia have been recognized at 9-10 10 sec TWT in correspondence to the front of the mountain chain. The CROP-04 line cannot provide information on the extent of this reflective unit the 10 sec TWT of time record of the re-processed stack are insufficient for this purpose. 4) As concerns the backstop of the orogenic system, the CROP-04 profile indicates that it must be located somewhere in the Tyrrhenian Sea, west of the line termination. Also the trailing edge of the Apuliacarbonate duplex system must be searches in the offshore west of the line termination
Patacca, Etta; Scandone, Paolo
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11568/195398
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 39
  • ???jsp.display-item.citation.isi??? ND
social impact