Lake Banyoles - First off-site archive for palaeoclimatic reconstruction on the Iberian Peninsula
During our field campaign in October 2010 a sediment core was collected from Banyoles Lake, drilled by our colleague Ramon Julià from the Institute of Earth Sciences „Jaume Almera“ (CSIC) in Barcelona, Spain. Analyses of this 67 m long sediment sequence began immediately and are now approaching completion.
Core logging with a Multi-Sensor Core Logger (MSCL) was provided by Michael Weber from the Department of Geology and Mineralogy in Cologne. MSCL generates data for magnetic susceptibility, gamma density, colour and p-wave velocity, as well as high resolution photographs. Moreover, equidistant sampling (every 10 cm) and preparation for application of Fourier transform infrared spectroscopy (FTIRS) to quantify biogeochemical parameters (e.g. TOC, TIC, TN and BSi) have been undertaken. Measurements were executed in cooperation with Peter Rosen and Hendrik Vogel from the Department of Ecology and Environmental Science in Umea, Sweden. In addition, field portable x-ray fluorescence analyses (FPXRF) are in progress, with kind support of Frank Lehmkuhl from the Department of Geography in Aachen. Furthermore, smear-slide analyses to find volcanic ashes from Olot (Garrotxa volcanic field) for tephrochronology promise some good results. To generate an age model for the sediment sequence from Banyoles Lake, several dating techniques (ESR, AMS-14C and U/Th) were applied. Although ESR dating has proceeded unsuccessful, others methods have given good results.
A visit to Barcelona in March 2011 (8th–11th) provided opportunity to discuss first results and to profit from R. Julià’s experience in working at Lakes on the Iberian Peninsula. Lake Banyoles is one of the most prosperous off-site palaeoclimatological archives on the Iberian Peninsula. Our results will be correlated with information of on-site archives of Late Pleistocene/Holocene palaeoclimatic variations.
Lake Banyoles seen from air and from the south.
Aerial view: Institut Carogràfic de Catalunya (http://www.icc.cat/vissir2/?lang=ca_ES)
Photo: Nicole Hörbig
Sediment core from Lake Banyoles.
Photo: Nicole Höbig