Late Quaternary alluvial fan systems in semiarid Chile: evolution and paleoclimate linkages. A workshop and field visit to catalyze US-Chile future collaboration

Affiliation(s)PIProject periodFunded by
DEES Antinao Rojas, Jose Luis 10/01/2011 - 09/30/2012 National Science Foundation

Project Description

During December 2011, DEES researchers Drs. Eric McDonald and Jose Luis Antinao travelled during ten days to visit field sites and research institutes in arid and semiarid Chile, with the main goal of planning future collaboration with Chilean institutions in the subjects related to paleoclimate/alluvial fan evolution linkages.  The project was funded by the National Science Foundation ‘Catalyzing New International Collaboration’ program and it was structured around a collaborative workshop of one day and a field visit of three days.  During these activities, the co-PIs and one graduate student from UCLA met and discussed potential collaboration ideas with Chilean researchers Dr. Antonio Maldonado (Center for Arid Zones Research, CEAZA at Universidad La Serena), Dr. Rodrigo Riquelme (Geociencias, Universidad Catolica del Norte, UCN, Antofagasta) and Dr. Gabriel Vargas (Department of Geology at Universidad de Chile, Santiago), along with other researchers, staff and student members of the Chilean research groups.

Both DRI researchers are actively investigating linkages between paleoclimate and alluvial activity in desert regions of the world.  The planning visit sought to establish a productive program of collaborative research between the Desert Research Institute and three Chilean universities, bringing together complementary skills to this and future projects. In this case, experience of DRI on soil and chronological analyses of alluvial fan evolution in arid regions of North America, Europe and the Middle East will be combined with expertise of Chilean researchers with extensive experience on South America paleoclimate and alluvial fan geomorphology.


Participants have discussion Outcrop Participants have discussion
Near Los Vilos, coastal semiarid Chile.
Massive outcrop in the Elqui Valley.
Workshop participants.

Several goals were accomplished during the visit:

  1. Participants identified common research interests and discussed strategies for future collaborative work during the one-day workshop carried out at CEAZA, in La Serena.  This allowed during the following days to sketch plans for collaborative work.
  2. A field visit of three days with the Chilean research group to key sites in the semiarid region between La Serena and Santiago was complemented with four days of pre- and post-workshop independent visit by the US-based researchers, being one of the most relevant components to design prospective studies to start collaboration.
  3. Preliminary sets of sediment and soil field observations and samples were taken to assess the optimal methodological approach for the region.
  4. US-based researchers shared current research on evolution of alluvial fans to a broader audience in the Chilean institutes, while getting a state-of-the-art view on paleoclimatic and geomorphological research in the region by the Chilean groups.

As a final outcome of this visit, several ideas are being considered in the mid-term for proposal development on all involved research groups.  Future activities also include planning new joint field visits, especially to regions in central Chile with a potential for high impact research.

Relevance of collaborative research

Late Pleistocene to Holocene paleoclimate variability is relatively well known for arid western South America through several proxy records already addressed by research of the Chilean group involved in this project. However, scattered data exist to verify linkages between alluvial and hillslope processes and the paleoclimate record. The study of these potential linkages is critical to assess hypotheses of South American climate variability over millennial timescales that affect directly landscape evolution, when independent use of geomorphological, paleohydrological or paleobotanical records produces ambiguous interpretations.

It is expected that development of collaborative research ties will boost research on arid region alluvial fan evolution, expanding the set of areas that can be used to test geomorphic models while providing an opportunity to test South American paleoclimate hypotheses.

Broader impact of the workshop and field visit

During the workshop, different topics related to the knowledge about arid region alluvial fan evolution, potential linkages to Quaternary climate variability in semiarid Chile and with global change were addressed.  Potential applications of advances in the knowledge of these topics through collaborative research include subjects of high societal relevance such as the assessment of hazards and risks in this tectonically active region.  The participation of early career researchers and students from both countries was encouraged; around 25 people attended the talks at CEAZA, while 10 people including undergraduate local students benefited from portions or the entire field visit.