Constructive and destructive episodes in the building of a young Oceanic Island, La Palma, Canary Islands, and genesis of the Caldera de Taburiente

The results of new field observations, 23 new KAr determinations and sixteen previously published determinations provide the basis for the reconstruction of the subaerial volcanic history of the island of La Palma, after the seamount activity represented by the materials of the Basal Complex. An eruptive phase between 2.0 and 1.3 Ma formed a large shield. A period of volcanic quiescence followed, until around 1 Ma, during which a large lateral collapse partly destroyed the former edifice. Between 1.05 and 0.7 Ma, activity was renewed in the shield and a N-S ridge was built in the southern part of the island. Around 0.7 Ma, two new large lateral collapses affected the western part of both edifices, and they were followed by eruptions between 0.71 and 0.65 Ma which built a new edifice that partly filled the depressions thus created. The Caldera de Taburiente constitutes the eroded remnants of the depression formed in the northern shield. From 0.65 Ma to present, activity has been restricted to the N-S ridge, which has continued to grow southwards. There was a general N-S migration of volcanic activity with time, but in the shield the trend was northwest to southeast. Eruptive rates seem to have been fairly constant during the different eruptive phases considered, between 0.15 and 0.37 km3/ka. A very similar succession of constructive and destructive episodes has been obtained for the neighboring island of Hierro, but in this case the activity started around 0.8 Ma and eruptive rates were about 0.5 km3/ka.

[1]  E. Middlemost.  San Miguel de La Palma — A volcanic island in section , 1970 .

[2]  H. Staudigel,et al.  The history of intrusive activity on the island of La Palma (Canary Islands) , 1986 .

[3]  A. Cendrero,et al.  K-Ar chronology of the volcanic eruptions in the Canarian archipelago: Island of La Gomera , 1984 .

[4]  C. Gagel,et al.  Die mittelatlantischen Vulkaninseln , 2022 .

[5]  R. Steiger,et al.  Subcommission on geochronology: Convention on the use of decay constants in geo- and cosmochronology , 1977 .

[6]  L. Siebert.  Large volcanic debris avalanches: Characteristics of source areas, deposits, and associated eruptions , 1984 .

[7]  N. Watkins,et al.  Potassium-argon ages, volcanic stratigraphy, and geomagnetic polarity history of the Canary Islands; Tenerife, La Palma and Hierro , 1972 .

[8]  Antonio Cendrero,et al.  Volcanic evolution of the island of Tenerife (Canary Islands) in the light of new K-Ar data , 1990 .

[9]  G. Boudon,et al.  The primitive volcano of Mount Pelée: its construction and partial destruction by flank collapse , 1989 .

[10]  H. Staudigel,et al.  The Pliocene seamount series of La Palma/Canary Islands , 1984 .

[11]  Juan Coello Aranda,et al.  Geocronología de la Isla de El Hierro (Islas Canarias) , 1993 .

[12]  H. Schmincke.  The Geology of the Canary Islands , 1976 .

[13]  A. Pacheco,et al.  Las extrusiones sálicas del sur de la isla de Palma , 1983 .

[14]  T. Ui,et al.  Characterization of debris avalanche deposits in Japan , 1986 .

[15]  W. Duffield,et al.  Huge landslide blocks in the growth of piton de la fournaise, La réunion, and Kilauea volcano, Hawaii , 1982 .

[16]  J. Cantagrel,et al.  Avalanches et coulées de débris : le volcan du Guéry ; ou est la caldéra d'éffrondement dans le massif des Monts dore? , 1990 .

[17]  Antonio Cendrero,et al.  Evolution of the eastern volcanic ridge of the Canary Islands based on new KAr data , 1992 .

[18]  E. Middlemost.  Evolution of La Palma, Canary archipelago , 1972 .