Palaeoenvironmental changes in the Iberian central system during the Late-glacial and Holocene as inferred from geochemical data: A case study of the Navamuño depression in western Spain

• Published in: CATENA
• Main Authors: Turu, Valentí, Carrasco, Rosa M., López Sáez, José Antonio, Pontevedra Pombal, Xabier, Pedraza, Javier, Luelmo Lautenschlaeger, Reyes, Pérez Díaz, Sebastián, Echeverria Moreno, Anna, Frigola, Jaime, Alba Sánchez, Fracisca, Sánchez Vizcaíno, Jesús, Pèlachs Mañosa, Albert, Cunill Artigas, Raquel, Nadal Tersa, Jordi, Mur Cacuho, Elena, Soriano López, Juan Manuel
• Other Authors: Ministerio de Ciencia, Innovación y Universidades (España)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2021
• Subjects: Late Glacial; Holocene; Geochemistry; Palaeoclimate; Dust-Ashs-Aerosols; Greenland; Poblete
• Online Access: http://hdl.handle.net/10261/257628

The Iberian Central System (ICS) is a clue region to reveal Mediterranean/Atlantic inferences over Iberia. We present a multidisciplinary study from western Spain conducted in the Navamuño depression (ND), covering the last 16.8 ka (cal BP). A reconstruction of the palaeotemperature from the resulting geochemical data highlights four cold and dry intervals, namely, the Oldest Dryas, Older Dryas, Intra-Allerød Cold Period (IACP), and the Younger Dryas, along with warmer intervals: the Bølling (14.7–14 ka) and the Allerød (12.9–12.6 ka); however, the Greenland Interstadial GI-1c (13.4–13.1 ka) is barely distinguishable in the ND. Despite the shortage of biomass to sustain fire, the earliest charcoals are from ~14.4–13.8 ka. Evidence of ash/dust events overprinting the geochemical background starts at ~13.8–12.8 ka. Significant fire activity in the Early Holocene at ~11.7–10.6 ka affected the ND, matching the westernmost ICS data. This period includes short oceanic spells inferred from Cl peaks at ~10.9–10.2 ka and three cold intervals at 11.4, 9.3, and 8.2 ka disrupted the progressive temperature increase. The Mid-Holocene showed a continuously increasing trend towards an arid climate, peaking at 4.2 ka under a pervasive dust influx from North Africa, which has prevailed since almost ~7.9 ka. A prominent volcanic event at ~6.8–5.8 ka is in Navamuño and Roñanzas (Asturias, N Spain; Gallego et al., 2013) identified from heavy metal-rich layer, synchronous with the last known eruption of the Calatrava volcanic field (South-Central Spain; Poblete-Piedrabuena et al., 2019). This volcanic eruption could affect many other regions half north of Iberia. The pervasive presence of oceanic aerosols in the last three millennia (2.8 ka ~ ) allowed the formation of a Cl-rich peat layer during the Ibero-Roman humid period ~2.1 ka, before a changing around ~0.4 ka toward colder and drier conditions at the Little Ice Age (LIA) period. This study was funded by the LATESICE-CGL2016-78380-P, FINICES- PID2020-117685 GB-I00 and ...