Field Trip 5 - Tide-influenced deposits in the Jurassic and Lower Cretaceous of the Neuquén Basin: from coastal to offshore systems
Unfortunately, this field trip has been cancelled
Postconference, 4 days (November 21st-24th)
Leaders
Ernesto Schwarz1, Steve Flint2, Gonzalo Veiga1 and Marcello Gugliotta2
1 Centro de Investigaciones Geológicas. CONICET-Universidad Nacional de La Plata, La Plata, Argentina
2 Stratigraphy Group - Basin Studies and Petroleum Geoscience. School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester, UK.
Contact: eschwarz@cig.museo.unlp.edu.ar
Description
This field trip to the Neuquén Basin provides an excellent opportunity to observe the geology and to enjoy the superb tide-related outcrops of one of the most important petroleum basins of Argentina. Several tide-influenced systems developed through its evolution, being the Lajas system (Jurassic) the most extensively studied.
The Lajas Formation deposits have already become a world-class example for reservoir analogues, mostly from delta-front and delta-plain settings. However, recent studies challenged some of the original ideas regarding how much influence of tidal processes are recorded in these deposits, and, at the same time, they highlighted the variability of processes that can influence deposition along depositional strike. Relatively unconfined, tide-influenced deposits also formed during the Jurassic and the Early Cretaceous, probably representing offshore sand ridges and/or dune fields. Examples elaborated on both pure siliciclastic (Lajas Formation) and mixed clastic/carbonate (Agrio Formation) sediments will be shown and discuss in this trip. Finally, an example of fluvial-tidal interactions in a Lower Cretaceous succession will be visited. The tide modulation (and its expression) on rivers will be discussed, together with the stratigraphic record of net transgressive river-to-estuarine successions. In summary, this field trip will highlight and discuss the facies, depositional systems and stratigraphic architecture of different types of tide-related successions, covering a wide variety of settings, from coastal plains, trough tide-dominated deltas, to tide-influenced offshore settings.
Itinerary
This field trip would dedicate two days to the Lajas examples concerning delta-front and delta-plain deposits and their variability along depositional strike. The third day will be devoted to examples involving open-marine, tide-influenced deposits (Lajas and Agrio Fms), whereas in the last day we will discuss fluvial-tidal interactions in coastal-plain/estuarine settings (Mulichinco Fm). All of the examples are easily accessible from pavement or dirt roads and they are nearby Zapala, the second largest city within the Neuquén Basin, which has good facilities and accommodation. Zapala is two-hours drive from the Neuquén Airport, which connects with several cities of the country (including Buenos Aires and Comodoro Rivadavia; presently, no direct flights from Trelew (Puerto Madryn airport) connect to Neuquén).
Duration: 4 days / 3 nights
Departure: Neuquén Airport, Saturday, November 21, 8:00 AM
Arrival: Neuquén Airport, November 24, evening (estimated 7:00 PM)
Transportation: mini-bus
Degree of difficulty and weather: Medium degree of difficulty (some short walks and moderate climbing, most outcrops are close to the road). Weather in November can range from very warm (30°C) to cold and windy. Accommodation in hotels is based on double rooms.
Number of participants: minimum 12 - maximum 20
Estimated cost: about USD 900
Booking:your booking will be confirmed upon receipt a deposit of USD 350.00 per person.
Image caption: general view of the Lajas Formation outcrops at Bajada de Los Molles and some of their most common facies.