Geometrical and geotechnical characterization of the earth fissures appeared in the Guadalentín Valley (southeastern Spain) after the September 2012 flooding
Two earth fissures appeared in Murcia province (southeastern Spain) after the flood occurred because of a heavy downpour on 28 September 2012. In this area, located within the Guadalentín Valley, up to 212 L m−2 was reported that day. More than 200 agricultural exploitations were destroyed by the fl...
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Published in | Proceedings of the International Association of Hydrological Sciences Vol. 382; pp. 663 - 667 |
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Main Authors | , , , , , , , , , |
Format | Journal Article Conference Proceeding |
Language | English |
Published |
Gottingen
Copernicus GmbH
01.01.2020
Copernicus Publications |
Subjects | |
Online Access | Get full text |
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Summary: | Two earth fissures appeared in Murcia province (southeastern Spain)
after the flood occurred because of a heavy downpour on 28 September 2012.
In this area, located within the Guadalentín Valley, up to 212 L m−2 was reported that day. More than 200 agricultural
exploitations were destroyed by the flooding, with a devastating effect on
many infrastructures, such as a main A-7 highway bridge that collapsed in
this event. The earth fissures appeared after this flooding in the towns of
Puerto Lumbreras and Totana. The first fissure showed a straight-line
direction approximately parallel to the main geological structures of the
Guadalentín Valley. The total length of the fissure was 400 m and was 2 to 3 m in depth. The soil in the fissure is classified as a low-plasticity silt with
some sand and clay, ML, according to the Unified Soil Classification System.
From the sieve and hydrometer tests, the percentage of silt in these samples
was between 48 % and 68 %, the clay content between 12 % and 30 % and the sand
content between 2 % and 40 %. The plasticity index was smaller than 9.2 for all
the samples. To evaluate the piping and internal erosion susceptibility of
the soil, pinhole, crumb and geochemical tests were done on the collected
samples. A result of non-dispersive soil was obtained from crumb and pinhole
tests. Nevertheless, the pH, sodium adsorption ratio and exchangeable sodium
percentage tests showed that some samples could be affected by the
dispersion of the soil. Also, the collapsible potential of the soil was
studied, showing negative results for all the samples except for that
collected at the southern end of the fissure, which showed a medium to high
potential. Concerning the Totana fissure, it appeared with different
branches and holes instead of as a rectilinear pattern. The total length of
the fissure was 190 m, with the soil characterized as a silty soil. Lastly,
INSAR data, GPS, GPR and land subsidence maps were used to study the
possible origin of these fissures. |
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ISSN: | 2199-899X 2199-8981 2199-899X |
DOI: | 10.5194/piahs-382-663-2020 |