Leakage of Active Crater lake brine through the north flank at Rincón de la Vieja volcano, northwest Costa Rica, and implications for crater collapse

2000 ◽  
Vol 97 (1-4) ◽  
pp. 143-159 ◽  
Author(s):  
K.A. Kempter ◽  
G.L. Rowe
2021 ◽  
Author(s):  
Herlan Darmawan ◽  
Suratman Worosuprojo ◽  
Wahyudi Wahyudi ◽  
Agung Harijoko ◽  
Haryo Edi Wibowo ◽  
...  

Abstract After the 22 December 2018 flank collapse, series of hydrothermal, phreatomagmatic, and effusive eruptions occurred and changed the morphology of Anak Krakatau. The ejected volcanic materials enlarge and increase the elevation of the west flank, which may indicate a reconstruction phase of the Anak Krakatau edifice. Here, we investigated the morphological changes of Anak Krakatau between 2019 and 2020 by using drone SfM photogrammetry, Sentinel and Pleiades satellite imageries, and fieldworks photograph data. The result shows volcaniclastic deposit due to the hydrothermal and/or phreatomagmatic eruptions that covered 0.08 km2 around an active crater lake at Anak Krakatau between February and January 2020. The large phreatomagmatic and effusive eruptions on 10 April 2020 produced tephra and lava flow deposits that significantly changed the morphology of Anak Krakatau. The deposit of tephra covered 0.815 km2 at the north – northwest flanks of Anak Krakatau, while the lava flow emplaced 0.2 km2 and elongated around 742 m from the pre-existing crater lake to the west shoreline of Anak Krakatau. The lava flow has a blocky surface and highly fractured that possibly formed due to compression – extension stresses during lava flow emplacement. The emplacement of the massive lava flow at the pre-existing crater lake may change the future eruption style at Anak Krakatau, which was previously dominated by hydrovolcanism activities, such as hydrothermal and phreatomagmatic events.


2000 ◽  
Vol 97 (1-4) ◽  
pp. 127-141 ◽  
Author(s):  
M Martı́nez ◽  
E Fernández ◽  
J Valdés ◽  
V Barboza ◽  
R Van der Laat ◽  
...  

2019 ◽  
Vol 51 (6) ◽  
pp. 515-559
Author(s):  
Gothamie WEERAKOON ◽  
André APTROOT ◽  
Robert LÜCKING ◽  
Omal ARACHCHIGE ◽  
Siril WIJESUNDARA

AbstractWe provide an updated survey for Sri Lanka of species of Graphis sensu Staiger, recently divided into Graphis s. str. and Allographa, including brief descriptions and a key to all 124 species currently known. Six new species are described: Allographa bambusicola Weerakoon, Lücking & Aptroot, a bambusicolous Allographa with entire labia, a laterally carbonized excipulum, 80–100 × 15–17 µm large, muriform ascospores and a rather thick, irregularly verrucose lateral thalline margin of the lirellae; A. weerasooriyana Weerakoon, Arachchige & Lücking, a corticolous Allographa resembling A. rustica Kremp. in overall anatomy and chemistry, but with a verrucose thalline margin of the lirellae and labia not distinctly raised above the thalline margin; Graphis flosculifera Weerakoon, Lücking & Aptroot, a corticolous Graphis resembling G. insulana but differing in the unique disposition of the lirellae and the slightly more elongate ascospores; G. rajapakshana Weerakoon, Lücking & Aptroot, a corticolous Graphis resembling G. desquamescens, including in ascospore size, but with lirellae with a distinct lateral thalline margin; G. rimosothallina Weerakoon, Lücking & Aptroot, a corticolous Graphis with a thick, uneven, rimose thallus and Fissurina-like lirellae, a completely carbonized excipulum and transversely 7-septate ascospores, 32–37 × 8–10 µm; and G. thunsinhalayensis Weerakoon, Arachchige & Lücking, a corticolous Graphis resembling G. subalbostriata but with smaller ascospores and lacking white lines between the striae of the labia. We also validate the name G. verrucoserpens Lücking. A total of 106 species are reported here for the first time from Sri Lanka. A biogeographical comparison with two other well-sampled countries (Costa Rica and Thailand) revealed a significantly higher similarity in species composition with Costa Rica than between Thailand and Costa Rica, suggesting a potential signature of the ‘biotic ferry’ hypothesis, that is the migration of lineages from Gondwana (partly corresponding to the modern Neotropics) via the north-eastwards drifting Indian subcontinent and subsequent interchange with Laurasia (partly corresponding to the modern eastern Paleotropics). However, the evolutionary timeline of the clades involved does not support this hypothesis and suggests an alternative explanation of geologically more recent mid- to long-distance dispersal.


2000 ◽  
Vol 54 (1) ◽  
pp. 24-37 ◽  
Author(s):  
Kenneth H. Orvis ◽  
Sally P. Horn

Glacial lake sediments and glacial geomorphology in Valle de las Morrenas, a glacial trough on the north face of Cerro Chirripó, Costa Rica, provide evidence on high-altitude Pleistocene conditions in Central America. The most recent glacier in the valley (Chirripó stage I) receded very rapidly near the end of the Younger Dryas chronozone. Radiocarbon dates on basal organic sediments from lakes beneath upper, middle, and lower limits of that glacier fall close together, and two-sigma calibrated ages overlap for the period 9700–9600 cal yr B.P. Earliest datable transition sediments from the central lake date to 12,360–11,230 cal yr B.P. Larger, older moraines, and associated trimlines, allowed reconstruction of three paleoglaciers (Chirripó stages II, III, and IV). Computer analysis of hypsometry using published tropical-glacier vertical mass balance profiles yields ELAs of 3506–3523, 3515–3537, and 3418–3509 m, respectively; Chirripó II ELA-estimate positions applied to Chirripó I yield an ELA of 3538–3546 m. We infer minimal temperature depressions of 7.4–8.0°C for the Chirripó I–IV stages. Modeling the behavior of modern tropical glaciers yields basinwide net accumulation estimates of 440–620, 550–830, and 960–1760 mm yr−1 for the Chirripó II, III, and IV stages.


Zootaxa ◽  
2008 ◽  
Vol 1798 (1) ◽  
pp. 1 ◽  
Author(s):  
M. S. STROTHER ◽  
C. L. STAINES

The North and Central American genus Fidia Baly 1863 (Coleoptera: Chrysomelidae) is revised. The genus is redescribed and a diagnosis separating Fidia from similar genera is provided. Twenty-four species are recognized: F. lateralis Jacoby 1882 is transferred to Xanthonia; Colaspis flavescens Sturm 1826 is a nomen nudum; F. sallei Lefèvre 1877 and F. unistriata Jacoby 1882 are synonymized with F. albovittata Lefèvre 1877; F. atra Jacoby 1882 is synonymized with F. spuria Lefèvre 1877. Twelve species are described as new- F. chapini from Mexico; F. comalensis from Mexico; F. convexicollis from Texas and Oklahoma; F. costaricensis from Costa Rica; F. delilahae from Alabama and Mississippi; F. dicelloposthe from Mexico; F. dichroma from Mexico; F. marraverpa from Mexico; F. papillata from Mexico; F. pedinops from Alabama, Florida, and Georgia; F. rileyorum from the southeastern United States; and F. xanthonioides from Mexico. Lectotypes are designated for F. albovittata Lefèvre 1877, F. cana Horn 1892, F. guatemalensis Jacoby 1879, F. lurida Lefèvre 1885, F. plagiata Lefèvre 1877, F. sallei Lefèvre 1877, F. spuria Lefèvre 1877, and F. unistriata Jacoby 1882. A key to the recognized species is presented and important taxonomic characters are illustrated. Distribution maps are provided for each species.


1992 ◽  
Vol 54 (6) ◽  
pp. 494-503 ◽  
Author(s):  
Gary L Rowe ◽  
Shinji Ohsawa ◽  
Bokuichiro Takano ◽  
Susan L Brantley ◽  
Jose F Fernandez ◽  
...  

2012 ◽  
Vol 2012 ◽  
pp. 1-4
Author(s):  
Joseph A. MacGown ◽  
James K. Wetterer

Gnamptogenys triangularis(Mayr), native to the forests of South and Central America, is a predatory ant that feeds on millipedes. In its native range, this species is known from Buenos Aires, Argentina (38.1°S) in the south to Costa Rica (10.4°N) in the north, with records from eight countries in South America (all except Chile, French Guiana, and Paraguay), and the two southernmost countries of Central America (Panama and Costa Rica). The first records ofG. triangularisoutside its native range came from Florida beginning in 1985 (six sites: 25.5°–30.4°N) and Alabama in 1996 (one site: 30.4°N). Here we present the first records ofG. triangularisfrom Mississippi, dating from 2002–2010 (five sites: 30.5°–31.2°N). Based on its South American range, it appears thatG. triangularishas the potential to spread to forests throughout much of the southeastern USA. There are no documented impacts ofG. triangularis,and it seems unlikely that this species will ever become a major pest.


1992 ◽  
Vol 49 (1-2) ◽  
pp. 23-51 ◽  
Author(s):  
Gary L. Rowe ◽  
Susan L. Brantley ◽  
Mario Fernandez ◽  
Jose F. Fernandez ◽  
Andrea Borgia ◽  
...  

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