A. Fildani, 2009. "Outcrop 3. Punta Barrosa Formation Sheet Complex, Headquarters’ Cliff", Stratigraphic Evolution of Deep-Water Architecture: Examples of controls and depositional styles from the Magallanes Basin, southern Chile, Andrea Fildani, Stephen M. Hubbard, Brian W. Romans, J.A. Covault, W.H. Crane, A. Bernhardt, Z.R. Jobe, D.A. Armitage, J.C. Fosdick, M.R. Shultz, J. Clark, D.R. Lowe, S.A. Graham
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Outcrop accessibility: easy Outcrop Coordinates: 51.1786°S, 72.9618°W Refer to outcrop 3 on location map
The Headquarters section (Fig. 3.1A), located within a few hundred meters of the Torres del Paine Park Headquarters, is one of the most accessible outcrops of the upper Punta Barrosa Formation. Stratigraphically, it sits directly below the first mudstone considered as part of the Cerro Toro Formation. This outcrop does not offer the same lateral continuity of exposure as the Marina’s cliff sections, but it presents an interesting packaging of slurry beds (S1) capped by amalgamated thick-bedded conventional turbidites.
In the lower part of the section, the stratigraphic packaging consists of an alternation of thin-bedded fine-grained turbidite packets with more resistant and massive slurry-bed packets. Thin-bedded turbidites include Tc,d,e intervals ranging in thickness from a few centimeters to a maximum of a few tens of centimeters. Slurry bed packets display well-developed meso- and macro-banding. No other sedimentary structures have been observed beyond rare climbing ripples in some of the fine-grained tops of sedimentation units. The lowest bed of the lowest slurry flow package is characterized by a superb example of multi-banding (Fig. 3.1B). It shows fourteen bands defined by dark and light coloration, and it is capped by a 5 cm thick ripple-laminated, fine-grained sandstone interval probably related to more typical turbiditic sedimentation. The top of the stratigraphic succession is capped by amalgamated, thick-bedded high-density turbidity current deposits stacked offset of one another (compensational stacking).
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Stratigraphic Evolution of Deep-Water Architecture: Examples of controls and depositional styles from the Magallanes Basin, southern Chile
This large format (11 × 17 inch) all color outcrop atlas and field guide was produced for the SEPM Research Conference held in Chile in February, 2009. It contains a wealth of information on the world class deep water outcrops of the Cretaceous of the Magallanes Basin in the Ultima Esperanza District, Chilean Patagonia. This book covers the significant outcrops in the region the Punta Barrosa Formation, CerroToro Fm., and the Tres Pasos Fm.