Geoarchaeology: An International Journal, Vol. 25, No. 4, 475–496 (2010 )
© 2010 Wiley Periodicals, Inc.
Published online in Wiley Interscience (www.interscience.wiley.com). DOI:10.1002/gea.20314
*Corresponding author; E-mail: jlpena@unizar.es.
Alluvial Geoarchaeology of an
Ephemeral Stream: Implications for
Holocene Landscape Change in the
Central Part of the Ebro Depression,
Northeast Spain
Ana Constante,
1
José Luis Peña-Monné,
2,
* and
Arsenio Muñoz
3
1
Instituto Pirenaico de Ecología, CSIC, Campus de Aula Dei, P.O. Box 13034,
50080-Zaragoza, Spain
2
Department of Geography and Land Management, University of Zaragoza,
50009-Zaragoza, Spain
3
Department of Earth Sciences, Faculty of Sciences, University of Zaragoza,
50009-Zaragoza, Spain
La Virgen is an ephemeral tributary of the Ebro River in northeast Spain with a complex allu-
vial sequence. We analyzed alluvial stratigraphy to develop a model of Holocene fluvial evo-
lution for La Virgen and infer causes of floodplain dynamics. Three alluvial terraces were
mapped and described using a combination of geoarchaeological and geomorphological tech-
niques. Stratigraphic ages were estimated using
14
C dating and archaeological remains.
Sedimentation in the valley floor commenced in the Neolithic period ca. 6000 BC and contin-
ued during the Bronze and Iron ages (ca. 1800–500 BC), the Iberian and Roman periods
(ca. 500 BC–AD 500), and the Middle Ages (ca. AD 500–1500). The main terrace (N3) is 14 m
thick and predominantly composed of sand, silt, and clay that we believe are derived from
local hillslopes and represent a long period of human-induced soil erosion that intensified
during the Bronze and Iron ages until the Late Roman period. © 2010 Wiley Periodicals, Inc.
INTRODUCTION
Geomorphological studies focused on the Holocene have increased in recent
decades because of increased interest in understanding climate–human interactions
at various temporal and spatial scales. These studies include investigations of the
short-term environmental effects of rapid climate change on land cover and hillslope
erosion. More than 40 years ago C. Vita-Finzi (1969) conducted a geoarchaeological
study of several Mediterranean valleys and found evidence for two main stages of
alluviation corresponding to the beginning of the Holocene (older fill) and the Late