4.1 Measured sections

An overview of the measured sections, including some general stratigraphic remarks, is here provided. The same or equivalent logs, measured by former workers, are reported as well.

SECTION [4]

This section was measured along and in proximity (“Les Teuleres” outcrop) of the C-13 roadcut close to the village of La Baronia de Sant Hoisme.

It represents a time interval extending from the lower Danian to the lower Ypresian, and hosts a major hiatus close to its base (Middle Paleocene Unconformity, CHAP).

The section includes continental (and subordinate marine) deposits of Paleocene and Lower Ypresian age, and a marine succession of lower Ypresian age mainly represented by carbonate deposits of the Cadì fm. and hybrid arenites of the Lower Baronia fm.

The succession hosts three main sequences or allogroups that belong to the Lower Tremp-Ager Group (LTAG), the Upper Tremp-Ager Group (UTAG) and the Lower Figols Group (LFG).

Compare the lower part of this section (Paleocene) with Fontllonga section in Colombo &

Cuevas, 1993 (including the lower Ypresian Cadì fm.) and the Lower Ypresian interval with the Ager section in Ferrer et al., 1973; Ager section in Mutti et al. (1994, plate II; section 5 in plate III);

reference section in Ghielmi (1991); Ager section in Angella (1999).

SECTION [10]

This section was measured in proximity of a local relief named “Mas del Boix”, about 2,5 Km east of section [4].

It represents a time interval included between the latest Thanetian and the earliest Ypresian and it hosts the LTAG\UTAG allogroup boundary.

SECTIONS [1, 2, 3, 5, 6, 7, 8, 9]

These sections only encompass the LFG sequence, and were measured in a relatively continuous outcrop belt from the “Barranco de Marcò” to the west and the eastern end of the cliff named “Les

Alteres”.

Compare with the logs from the FG 1 stratigraphic cross-section in Ghielmi (1991), Mutti et al.

(1994, plate III).

SECTION [11]

This is a very short log, measured only to verify the lateral continuity of the units exposed in section [10] in the most thinned sector of the Paleocene of the Ager basin, in proximity with the local culmination of the St. Mamet anticline, on a local relief named “Rocaspana”, near the village of Peralba.

SECTION [12]

This is a composite section measured on both sides of the Rio Noguera Pallaresa in the northernmost reaches of the Ager syncline (close to the Ager/Temp/Balaguer crossroad). It hosts a thin continental succession, correlated in this work with the lower portion of section [4], that comprises the Middle Paleocene Unconformity (see chapters 5.x and 6.x CHAP), and a marine succession of Lower Ypresian age; this is in turn unconformably overlain by middle/upper Ypresian deposits of the Upper Figols Group (UFG).

The sequence stratigraphic subdivision of this interval is discussed in chapter 6.x CHAP, but it clearly encompass part of the LTAG, and part of the UTAG.

The only formerly published versions of this section are apparently the ones from Ferrer et al.

(1973) and Mutti et al. (1985); both papers refer to it as the “Pasarela Section”, and only document its lower portion.

SECTION [13, 14]

This is a composite section measured on both sides of the Rio Noguera Ribagorçana, in the locality named “Congost de Mont Rebei”. It hosts a thin continental succession, including the top of the LTAG, and the whole UTAG and LFG, expressed by prevalently marine carbonatic and muddy deposits.

Compare with the Ribagorçana section in Waehry (1999) and Mont Rebei section in Baceta et al. (2011).

SECTION [15]

It is exposed along the roadcut between between the villages of St. Esteve de la Sarga and Castellnou del Montsec, and was measured only to check on thicknesses in the lower interval of the

UTAG as observed in section [13, 14].

SECTION [16]

This is a composite section measured between the villages of Alsina and Moror. It encompasses a marine, mainly carbonatic succession, including the whole UTAG and LFG, and is treated in detail in CHAP of this chapter.

Compare with Alsina section in Waehry (1999).

SECTION [17]

This is a composite section measured along the relief comprised between the villages of Guardia de Noguera and Mur, an it hosts a marine carbonate/muddy succession, comprising most of the UTAG and the whole LFG.

Compare with section 6 in Fonnesu (1984) and Guardia de Noguera section in Angella (1999).

SECTION [18]

This section was measured along the hill named “Serra Puit”, and is mainly represented by marine deposits (mudstones and subordinate carbonate and mixed carbonate-siliciclastic beds). It includes part of the UTAG and LFG.

Compare with section 7 in Fonnesu (1984) and Serra Puit section in Angella (1999).

SECTION [19]

This is a composite section measured between the villages of Puigmaçana and Villamolat.

The upper portion of the succession, above the UTAG\LFG boundary, is poorly exposed, so correlations in this interval are not reliable; nevertheless, the overall thickness of the LFG was reliably measured. Section [19] hosts a muddy succession with subordinate sandstones and sandy limestones, comprising most of the UTAG (the location of UTAG base is uncertain) and the LFG.

Compare with Puigmaçana section in Angella (1999).

SECTION [20]

This is a composite section equivalent to the classic “Tremp section”.

The lower portion was measured in the Rio Palau incision, west of Palau de Noguera, along the

“Tossal” hill and the C-1311 roadcut (between Tremp and the Montllobat pass) in its upper part.

It hosts a marine muddy succession, with the exception of its lowermost interval represented by continental deposits. The muddy succession is punctuated by sandstone and mixed

carbonate-siliciclastic beds, and subordinate limestones and sandy limestones.

This section encompasses the full UTAG and LFG, but wide intervals are incomplete in the upper portion of UTAG because of plant cover.

Compare with sections 15 and 17 in Fonnesu (1984), Tremp section in Mutti et al. (1988), Eichenseer & Luterbacher (1992) and Angella (1999).

SECTION [21]

This section was measured in the “Barranc de Forats” incision, north of the C-1311 road.

It only encompasses the lower UTAG sequences, and it hosts a muddy succession similar to the one of section [20], including the basal continental deposits.

Compare with Eroles section in Angella (1999).

SECTION [22]

This section was measured in the “Barranc de Tendrui” incision, north of the village of Tendrui.

It encompasses the same stratigraphic interval of section [21].

Compare with section 23 in Fonnesu (1984) and S. Adrià section in Angella (1999).

SECTION [23]

This section was measured along a cliff exposure between the villages of Arèn and Esplugafreda.

The lower, continental interval of the succession, including the upper part of the LTAG, is taken from Schmitz & Pujalte (2005) and Baceta et al. (2011). The upper, marine interval, mainly represented by limestone bodies and mudstones, with subordinate sandy deposits, is unconformably overlain by upper Eocene continental deposits, and it only encompasses the UTAG1 and2 sequences.

In document Integrated stratigraphy of the upper Paleocene-lower Eocene successions of the Tremp and Ager basins (south-central Pyrenees, Spain) (Page 73-77)