scholarly journals Syn-Eruptive Lateral Collapse of Monogenetic Volcanoes: The Case of Mazo Volcano from the Timanfaya Eruption (Lanzarote, Canary Islands)

2020 ◽  
Author(s):  
Carmen Romero ◽  
Inés Galindo ◽  
Nieves Sánchez ◽  
Esther Martín-González ◽  
Juana Vegas
Keyword(s):  
Canary Islands ◽  
Great Part ◽  
Volcanic Hazards ◽  
Debris Avalanche ◽  
Mitigation Strategies ◽  
Morphological Data ◽  
Flank Collapse ◽  
Tectonic Process ◽  
Eruptive Style ◽  
History Of

The evolution of complex volcanic structures usually includes the occurrence of flank collapse events. Monogenetic cones, however, are more stable edifices with minor rafting processes that remove part of the cone slopes. We present the eruptive history of Mazo volcano (Lanzarote, Canary Islands), including the first detailed description of a syn-eruptive debris avalanche affecting a volcanic monogenetic edifice. The study and characterization, through new geological and morphological data and the analysis of a great number of documentary data, have made it possible to reinterpret this volcano and assign it to the Timanfaya eruption (1730–1736). The eruptive style evolved from Hawaiian to Strombolian until a flank collapse occurred, destroying a great part of the edifice, and forming a debris avalanche exhibiting all the features that define collapsing volcanic structures. The existence of blocks from the substrate suggests a volcano-tectonic process associated with a fracture acting simultaneously with the eruption. The sudden decompression caused a blast that produced pyroclasts that covered most of the island. This study forces to change the current low-hazard perception usually linked to monogenetic eruptions and provides a new eruptive scenario to be considered in volcanic hazards analysis and mitigation strategies development.

scholarly journals Revisiting the tsunamigenic volcanic flank collapse of Fogo Island in the Cape Verdes, offshore West Africa

2019 ◽  
Vol 500 (1) ◽  
pp. 13-26 ◽  
Author(s):  
Rachel Barrett ◽  
Elodie Lebas ◽  
Ricardo Ramalho ◽  
Ingo Klaucke ◽  
Steffen Kutterolf ◽  
...  
Keyword(s):  
Large Scale ◽  
Debris Avalanche ◽  
Volcanic Material ◽  
Flank Collapse ◽  
Bathymetric Data ◽  
Medium Resolution ◽  
History Of ◽  
Seafloor Sediments ◽  
Multi Phase ◽  
Mass Transport Deposits

AbstractVolcanic archipelagos are a source of numerous on- and offshore geohazards, including explosive eruptions and potentially tsunamigenic large-scale flank collapses. Fogo Island in the southern Cape Verdes is one of the most active volcanoes in the world, making it both prone to collapse (as evidenced by the c. 73 ka Monte Amarelo volcanic flank collapse), and a source of widely distributed tephra and volcanic material. The offshore distribution of the Monte Amarelo debris avalanche deposits and the surrounding volcaniclastic apron were previously mapped using only medium-resolution bathymetric data. Here, using recently acquired, higher-resolution acoustic data, we revisit Fogo's flank collapse and find evidence suggesting that the deposition of hummocky volcanic debris originating from the failed eastern flank most likely triggered the contemporaneous, multi-phase failure of pre-existing seafloor sediments. Additionally, we identify, for the first time, multiple mass-transport deposits in the southern part of the volcaniclastic apron of Fogo and Santiago based on the presence of acoustically chaotic deposits in parametric echo sounder data and volcaniclastic turbiditic sands in recovered cores. These preliminary findings indicate a long and complex history of instability on the southern slopes of Fogo and suggest that Fogo may have experienced multiple flank collapses.

scholarly journals Modeling of partial dome collapse of La Soufrière of Guadeloupe volcano: implications for hazard assessment and monitoring

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Marc Peruzzetto ◽  
Jean-Christophe Komorowski ◽  
Anne Le Friant ◽  
Marina Rosas-Carbajal ◽  
Anne Mangeney ◽  
...  
Keyword(s):  
Coulomb Friction ◽  
Hazard Analysis ◽  
Debris Avalanche ◽  
Flank Collapse ◽  
Barrier Effects ◽  
History Of ◽  
Assessment And Monitoring ◽  
Coulomb Friction Law ◽  
Dome Collapse ◽  
Best Fit

Abstract Over the past 9,150 years, at least 9 flank collapses have been identified in the history of La Soufrière of Guadeloupe volcano. On account of the volcano’s current unrest, the possibility of such a flank collapse should not be dismissed in assessing hazards for future eruptive magmatic as well as non-magmatic scenarios. We combine morphological and geophysical data to identify seven unstable structures (volumes ranging from 1 × 106 m3 to 100 × 106 m3), including one that has a volume compatible with the last recorded flank collapse in 1530 CE. We model their dynamics and emplacement with the SHALTOP numerical model and a simple Coulomb friction law. The best-fit friction coefficient to reproduce the 1530 CE event is tan(7°) = 0.13, suggesting the transformation of the debris avalanche into a debris flow, which is confirmed by the texture of mapped deposits. Various friction angles are tested to investigate less water-rich and less mobile avalanches. The most densely populated areas of Saint-Claude and Basse-Terre, and an area of Gourbeyre south of the Palmiste ridge, are primarily exposed in the case of the more voluminous and mobile flank collapse scenarios considered. However, topography has a prominent role in controlling flow dynamics, with barrier effects and multiple channels. Classical mobility indicators, such as the Heim’s ratio, are thus not adequate for a comprehensive hazard analysis.

The Unknowable

2020 ◽  
Author(s):  
W. J. Mander
Keyword(s):  
Nineteenth Century ◽  
Great Part ◽  
Victorian Britain ◽  
History Of ◽  
First Philosophy

This book presents a history of nineteenth century metaphysics in Britain, providing close textual readings of the key contributions to First Philosophy made by the key philosophers of the period (such as Hamilton, Mansel, Spencer, Mill, and Bradley) as well as some lesser known figures (such as Bain, Clifford, Shadworth Hodgson, Ferrier, and John Grote). The story focuses on the elaboration of, and differing reactions to, the concept of the unknowable or unconditioned, first developed by Sir William Hamilton in the 1829. The idea of an ultimate but unknowable way that things really are in themselves may be seen as supplying a narrative arc that runs right through the metaphysical systems of the period in question as, relative to this concept, these thought schemes may be divided into three broad groups which were roughly consecutive in their emergence but also overlapping as they continued to develop. In the first instance there were the doctrines of the agnostics who further progressed Hamilton’s basic idea that fundamental reality lies for the great part beyond our cognitive reach, but these philosophies were followed, immediately by those of the empiricists and, in the last third of the century by those of the idealists, both of whom—albeit in profoundly different ways—reacted against the epistemic pessimism of the agnostics. By presenting, interpreting, criticizing and connecting together their various contrasting ideas this book explains how these three traditions developed and interacted with one another to comprise the history of metaphysics in Victorian Britain.

scholarly journals The evolutionary history of holometabolous insects inferred from transcriptome-based phylogeny and comprehensive morphological data

2014 ◽  
Vol 14 (1) ◽  
pp. 52 ◽  
Author(s):  
Ralph S Peters ◽  
Karen Meusemann ◽  
Malte Petersen ◽  
Christoph Mayer ◽  
Jeanne Wilbrandt ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Morphological Data ◽  
History Of

Fairuz

2021 ◽  
Author(s):  
Kenneth S. Habib
Keyword(s):  
Eastern Mediterranean ◽  
Great Part ◽  
Radio Station ◽  
Musical Style ◽  
Performance Practices ◽  
Good Friday ◽  
First Child ◽  
Latin Script ◽  
History Of ◽  
The Times

The Lebanese singer Fairuz is one of the most popular and critically acclaimed performers in the history of Arab musical arts. Born Nuhad Haddad in 1935, Fairuz attained extraordinary success, in great part, through her cultivation of an exceptional command of the voice, her development of a deep individual artistry, and her solid rooting in the performance practices of Lebanese and Arab art and popular song. From early in her career, this achievement was in collaboration with the Rahbani family of composer-poets. Assi Rahbani (b. 1923–d. 1986) and Mansour Rahbani (b. 1925–d. 2009) were siblings who worked together as the duo known as the Rahbani Brothers. Fairuz and the Rahbani Brothers met at the Lebanese Radio Station, where she took her professional name, and they began a collaboration there that gave rise to their first international hit in 1952. Occasionally, younger brother Elias Rahbani (b. 1938–d. 2021) joined in the composing as well. Following the marriage of Fairuz and Assi in 1954, Fairuz gave birth to their first child, Ziad Rahbani (b. 1956), who was raised in the presence of some of the most accomplished artists from across Arab society and who similarly showed a remarkable aptitude for musical arts early in life. Following the death of Assi in 1986, Ziad became the primary composer for Fairuz, after which her lyrical and musical style to some extent began increasingly to reflect more of the sensibilities of a younger generation. Since their beginnings, the Fairuz-Rahbani team has changed with the times and given rise to a prodigious artistic output that has included the production of operettas, musical theater sketches, musical films, and over a hundred record albums. Thematically, the wide-ranging repertoire has sometimes addressed universalistic spiritual matters with references to God, eternity, prayer, and other mystical subjects. The artists also have presented material of more expressly religious character that mentions churches, mosques, and houses of worship; that covers esteemed geographical locales, such as Jerusalem and Mecca; and that presents traditional repertoire like Good Friday chanting and Christmas carols. While Fairuz and the Rahbani composers are Christians, their repertoire has appealed across society irrespective of religious and sectarian affiliation. In the process, Fairuz has become a multifaceted icon to listeners from diverse backgrounds in Lebanon, throughout the eastern Mediterranean, across Arab society, and in the diaspora. As for transliteration of the names from Arabic into Latin script, “Rahbani” is fairly consistent, but “Rahbany” also occurs. The plural (i.e., three or more) is “Rahabina” and also is found in the forms “Rahbaniyun” and “Rahbaniyin” while in English it appears as “Rahbanis” as well. While the duo of the Rahbani Brothers has been consistently translated into English in this way, the Arabic form is either “al-Akhawan Rahbani” or “al-Akhawayn Rahbani” (i.e., the two Rahbani Brothers). “Fairuz,” which means “turquoise” in Arabic, has numerous variants in transliteration stemming, in part, from the various possibilities for each syllable of the name (e.g., Fairouz, Fayruz, etc.), but some degree of standardization has come, in part, from the use of this spelling by Voix de l’Orient, the record label that has produced the bulk of her recordings.

scholarly journals The taxonomic history of Indo-Papuan groundsnakes, genus Stegonotus Duméril et al., 1854 (Colubridae), with some taxonomic revisions and the designation of a neotype for S. parvus (Meyer, 1874)

Zootaxa ◽  
2018 ◽  
Vol 4512 (1) ◽  
pp. 1
Author(s):  
CHRISTINE M. KAISER ◽  
HINRICH KAISER ◽  
MARK O’SHEA
Keyword(s):  
New Guinea ◽  
Molecular Data ◽  
The Philippines ◽  
Morphological Data ◽  
Valid Species ◽  
Museum Specimens ◽  
Type Specimens ◽  
History Of ◽  
Original Species ◽  
Species Specific

Since its conceptualization in 1854, 29 species of the colubrid genus Stegonotus have been recognized or described, of which 15 (admiraltiensis, batjanensis, borneensis, cucullatus, derooijae, diehli, florensis, guentheri, iridis, heterurus, melanolabiatus, modestus, muelleri, parvus, poechi) are still considered valid today. Original species descriptions for the members of this genus were published in Dutch, English, French, German, and Italian and, perhaps as a consequence of these polyglot origins, there has been a considerable amount of confusion over which species names should be applied to which populations of Stegonotus throughout its range across Borneo, the Philippines, Wallacea, New Guinea, Australia, and associated archipelagos. In addition, the terminology used to notate characteristics in the descriptions of these forms was not uniform and may have added to the taxonomic confusion. In this paper, we trace in detail the history of the type specimens, the species, and the synonyms currently associated with the genus Stegonotus and provide a basic, species-specific listing of their characteristics, derived from our examination of over 1500 museum specimens. Based on our data, we are able to limit the distribution of S. modestus to the islands of Ambon, Buru, and Seram in the central Moluccas of Indonesian Wallacea. We correct the type locality of S. cucullatus to the Manokwari area on the Bird’s Head Peninsula of West Papua, Indonesian New Guinea and designate a neotype for S. parvus, a species likely to be a regional endemic in the Schouten Archipelago of Cenderawasih Bay (formerly Geelvink Bay), Indonesian New Guinea. We unequivocally identify and explain the problematic localities of the type specimens of S. muelleri and Lycodon muelleri, which currently reside in the same specimen jar. We remove L. aruensis and L. lividum from the synonymy of S. modestus and recognize them as S. aruensis n. comb. and S. lividus n. comb., respectively. We remove S. keyensis and Zamenophis australis from the synonymy of S. cucullatus and recognize them as S. keyensis n. comb. and S. australis n. comb., respectively. We further remove S. reticulatus from the synonymy of S. cucullatus, S. dorsalis from the synonymy of S. diehli, and S. sutteri from the synonymy of S. florensis. We designate lectotypes for S. guentheri, S. heterurus, S. lividus, and S. reticulatus. Lastly, we introduce S. poechi, a valid species not mentioned in the scientific literature since its description in 1924. This brings the diversity in the genus Stegonotus to 22 species. We also caution that in a complex group of organisms like Stegonotus any rush to taxonomic judgment on the basis of molecular and incomplete morphological data sets may perpetuate errors and introduce incongruities. Only through the careful work of connecting type material with museum specimens and molecular data can the taxonomy and nomenclature of complex taxa be stabilized. 

Notes on the generic position of Brassica deserti (Brassicaceae)

2019 ◽  
Vol 66 (1-2) ◽  
pp. 89-93
Author(s):  
Jotham Ziffer-Berger ◽  
Alexandra Keren-Keiserman ◽  
Adi Doron-Faigenboim ◽  
Klaus Mummenhoff ◽  
Oz Barazani
Keyword(s):  
Mediterranean Area ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Molecular Tools ◽  
East Mediterranean ◽  
Phylogenetic Groups ◽  
5.8S Rdna ◽  
The Core ◽  
Generic Position ◽  
History Of

Molecular tools provide new insights into phylogenetic relationships of plant species, and by relating phylogenetic groups to their geographical distribution, we can cast light upon the evolution history of plant clades. In the current study, we evaluated the phylogenetic position of the Sinai endemic Brassica deserti (Brassicaceae), later renamed as Erucastrum deserti, based on morphological data and 5.8S rDNA and ITS (Internal Transcribed Spacer) regions. Our results indicate that B. deserti belongs to an East-Mediterranean – Saharo Arabian clade and was not assigned to the core Brassica and Erucastrum clades, respectively, which evolved in the West Mediterranean area. We tentatively conclude that Brassica deserti evolved independently of core Brassica and Erucastrum.

scholarly journals Three new Cenomanian conifers from El Chango (Chiapas, Mexico) offer a snapshot of the geographic mosaic of the Mesozoic conifer decline

2021 ◽  
Author(s):  
Ixchel Gonzalez-Ramirez ◽  
Sergio RS Cevallos-Ferriz ◽  
Carl Rothfels
Keyword(s):  
Evolutionary History ◽  
Mixed Forest ◽  
Freshwater Ecosystems ◽  
Total Evidence ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Dominant Group ◽  
Geographic Mosaic ◽  
History Of ◽  
Rare Opportunity

Premise of study: El Chango is a recently discovered quarry that contains extremely well preserved fossils. The Cenomanian age of the locality corresponds to a time when the global flora was transitioning from gymnosperm- to angiosperm-dominated, yet conifers predominate in this locality. These fossils thus provide a rare opportunity to understand the replacement of conifers by angiosperms as the dominant group of plants. Methods: We collected material from El Chango in annual expeditions (2010 to 2014). We selected the three most abundant and best preserved conifer morphotypes and conducted a total-evidence (i.e., including molecular and morphological data) phylogenetic analysis of a sample of 72 extant conifer species plus the three fossils. We use these results to inform our taxonomic decisions. Results: We obtained four equally most-parsimonious trees (consistency index = 44.1%, retention index = 78.8%). Despite ambiguous relationships among some extant taxa, the three fossil conifers had the same phylogenetic position in all four most parsimonious trees; we describe these species as new: Sequoiadendron helicalancifolium sp. nov. (Cupressaceae), and Microcachrys rhomboidea sp. nov. and Dacrydium bifoliosus sp. nov (Podocarpaceae). The ecosystem is interpreted as a coastal humid mixed forest. Conclusions: Our findings contribute to the understanding of Cenomanian equatorialregions, and support the hypothesis of a geographically and ecologically structured rise of angiosperms, with conifers remaining dominant in brackish-water and angiosperms becoming dominant in freshwater-ecosystems. These fossils fill in gaps in the evolutionary history of lineages like Microcachrys, which we demonstrate occurred in the Northern hemisphere before becoming restricted to its current range (Tasmania).

scholarly journals High-resolution late Holocene sedimentary cores record the long history of the city of Cádiz (south-western Spain)

2020 ◽  
Vol 27 ◽  
pp. 35-47
Author(s):  
Ferréol Salomon ◽  
Darío Bernal-Casasola ◽  
José J. Díaz ◽  
Macarena Lara ◽  
Salvador Domínguez-Bella ◽  
...  
Keyword(s):  
Western Europe ◽  
High Energy ◽  
Mitigation Strategies ◽  
Urban Centre ◽  
Archaeological Data ◽  
Lisbon Earthquake ◽  
History Of ◽  
Western Spain ◽  
The One ◽  
The City

Abstract. Today, coastal cities worldwide are facing major changes resulting from climate change and anthropogenic forcing, which requires adaptation and mitigation strategies to be established. In this context, sedimentological archives in many Mediterranean cities record a multi-millennial history of environmental dynamics and human adaptation, revealing a long-lasting resilience. Founded by the Phoenicians around 3000 years ago, Cádiz (south-western Spain) is a key example of a coastal resilient city. This urban centre is considered to be one of the first cities of western Europe and has experienced major natural hazards during its long history, such as coastal erosion, storms, and also tsunamis (like the one in 1755 CE following the destructive Lisbon earthquake). In the framework of an international, joint archaeological and geoarchaeological project, three cores have been drilled in a marine palaeochannel that ran through the ancient city of Cádiz. These cores reveal a ≥50 m thick Holocene sedimentary sequence. Importantly, most of the deposits date from the 1st millennium BCE to the 1st millennium CE. This exceptional sedimentary archive will allow our scientific team to achieve its research goals, which are (1) to reconstruct the palaeogeographical evolution of this specific coastal area; (2) to trace the intensity of activities of the city of Cádiz based on archaeological data, as well as geochemical and palaeoecological indicators; and (3) to identify and date high-energy event deposits such as storms and tsunamis.

scholarly journals Un submarino alemán hundido en Maspalomas (1943

Cliocanarias ◽  
2021 ◽  
pp. 1-15
Author(s):  
Yago Abilleira Crespo ◽  
Keyword(s):  
Canary Islands ◽  
Second World War ◽  
World War ◽  
Political Ideologies ◽  
History Of ◽  
Second World

A brief history of the submarine U-167 which during the Second World War was bombed by British aircraft near the Canary Islands. Fearful local fishermen helped the shipwrecked; for them at sea there are no political ideologies when there are human lives to save. U-boat crew could return to their country and the submarine wreckage still gave a lot to talk about for some time.

Sign in / Sign up

Export Citation Format

Share Document