IRW19′ : 2-days Field Trip

The Mauléon-Arzacq rift system: A transect across a hyperextended rift system

Contributors: Emmanuel Masini, Julie Tugend, Rodolphe Lescoutre and Maxime Ducoux.

Download .kmz of stops Here

The aim of this field trip is to restore the geological evolution of the Mauléon-Arzacq rift system (SW France) that was partly inverted during the Pyrenean Orogeny and is suffering from poor outcropping quality. For this purpose, key field observations close to the mountain belt will be completed by sub-surface, thermochronological and thermal data to propose a present-day structure as well as a tectonic scenario for both the formation and deformation of the Mauléon-Arzacq rift system. Areas that will be visited in the southern limit of the Mauléon Basin corresponds to the southern border of the former rift basin that suffered from orogenic deformations. Further North, the basin is preserved but can only be explored through subsurface data, that will be discussed in the field and through presentations during the meeting.

Provisional Program

Day 1: Rifting, from crustal thinning to mantle exhumation.

  • Planned on Tuesday October 22nd
  • Departure from the hotel: 09:30 , back at the hotel: 18:30

Day 2: Basin evolution, from hyper-extension to orogenic inversion

  • Planned on Thursday October 24th
  • Departure from the hotel: 09:30, back at the hotel: 18:30

Note that, depending on wether conditions, days of fied trip can be adapted to limit risks. This decision will be taken at the beginning of the workshop.


Please be advised that weather can be wet and/or cold at this seasons in the area and we will visit places above 1000m asl.

No long walks are required, but please take appropriate mountain shoes, warm and rain clothes.

We will provide basic PPE (yellow jackets, hard hat)

HSE plans

Important : Non–french participants should ensure they have medical care coverage outside of their country of residence. The trip leaders & M&U sas decline any responsibility in health accidents.

Please find below:

  • The HSE guide for each stops for the 2-day field trip to build your HSE plan. All the relevant information, phone number, Hospital address can be found in this document. Please contact us in case of lacking information.
  • The HSE sheet for each stop, developed together with D. Steinhoff (BP) (thanks Doerte !!!)