Reply to Ponce et al. (2020)

We are delighted that the discrepancy, controversy or disagreement with the paper by Pazos et al. (2019) is finally channeled through a journal, which is the correct place for scientific debate of data and interpretations. Ponce et al. (2020) express the intention of "clarifying" omissions and misunderstandings about a classical section of the Lajas Formation. Before pointing out any comment, Ponce et al. (2020) suggest that the Lajas Formation is Middle Jurassic in age. However, it depends on the locality and the methodology used to calibrate the age. For instance, a Late Toarcian age was suggested by Pángaro et al. (2009, Fig. 5) for the basal part, while others like Stukins et al. (2013a) suggested an Early Bajocian-Early Callovian age for the entire unit. In particular, at Portada Covunco and using sequence stratigraphy correlations, Zavala and González (2001 Fig. 15) suggested a Late Bajocian age for a lower sequence (1 in Fig. 1) and an Early Bathonian age for an upper one (2 in Fig. 1). Interestingly, they included a gap Zavala and González (2001 Fig. 15) and a change in sandstone composition overlying the sequence boundary, suggesting different sedimentary supply areas for each one. On the other hand, the calibration ages with magnetostratigraphy performed by Iglesia Llanos et al. (2019) were based on pre-Callovian schemes like Zavala and González (2001). Conversely, macrofossils like bivalves (Trigonidae) suggest a Callovian age for part of the section (Lambert, 1944; Leanza and Garate-Zubillaga, 1987). The existence of a gap between the two sequences, compositional changes in sandstones, a change in the paleocurrent pattern, subaerial exposition below the sequence boundary and thickest beds close to the base (Fig. 1), with tidal features and bioclastic channeled deposits in the lower sequence, compared to a deepening trend with storm deposits documented by Pazos et al. (2019) above the sequence boundary depicted by Zavala and González (2001) permitted to disregard the evolution without any significant allocyclic time-controlled discontinuity in the proposed prodelta and delta front deposits suggested by Canale et al. (2015). Recently, a detrital zircon analysis by González Estebenet et al. (2020) also documents differences in morphology and habits of the zircons between the two sequences and reinforces the separate evolution in the sedimentary infilling.