Morphological and mineralogical characterization of speleothems from the Chimalacatepec lava tube system, Central Mexico
Por:
Lopez-Martinez, Rafael, Barragan, Ricardo, Beraldi-Campesi, Hugo, Lanczos, Tomas, Vidal-Romani, Juan R., Aubrecht, Roman, Bernal Uruchurtu, Juan P., Puig, Teresa Pi, Espinasa-Perena, Ramon
Publicada:
1 may 2016
Resumen:
Siliceous, opal-A speleothems of the Chimalacatepec lava tube system in
central Mexico are characterized here for the first time.
Morphologically, they can be classified into cylindrical and planar, and
display a wide array of shapes, inner textures, and locations within the
lava tube. All speleothems analyzed here are composed of opal-A, and
their pores are filled with calcite and monohydrocalcite. Microscopic
examination reveals a variety of microbial-looking, silicified filaments
and cell casts embedded within the micro lamination of the structures.
The abundance of biofilms in the Chimalacatepec lava tube may share
similarities with other volcanic caves elsewhere. The direct presence of
such bimorphs in the microstructure of the speleothems suggests the
biological mediation of these structures. Potential mechanisms include
nucleation and sorption of silica on extracellular polymeric substances
in the biofilms that, along with the SiO2 saturation in the water film
and evaporative effects, result in the formation of a speleothem. That
said, the presence of microbes in these and other cave systems, or their
inevitable interactions with the mineral phase of the speleothems,
should not be surprising. In view of this, these structures can be most
accurately described as biospeleothems. This study contributes to our
understanding of the diversity of such structures in these types of cave
systems and our ability to recognize the presence of microbes in these.
Filiaciones:
Lopez-Martinez, Rafael:
Univ Nacl Autonoma Mexico, Inst Geol, Ciudad Univ Campus, Mexico City 04510, DF, Mexico
Barragan, Ricardo:
Univ Nacl Autonoma Mexico, Inst Geol, Ciudad Univ Campus, Mexico City 04510, DF, Mexico
Beraldi-Campesi, Hugo:
Univ Nacl Autonoma Mexico, Inst Geol, Ciudad Univ Campus, Mexico City 04510, DF, Mexico
Lanczos, Tomas:
Comenius Univ, Fac Nat Sci, Dept Geochem, Mlynska Dolina Ilkovicova 6, SK-84215 Bratislava, Slovakia
Vidal-Romani, Juan R.:
Univ Geol Inst, Elvina Campus,ESCI 3 Bldg, Coruna 15071, Spain
Univ A Coruna, Geol Inst, Coruna 15071, Spain
Aubrecht, Roman:
Comenius Univ, Fac Nat Sci, Dept Geochem, Mlynska Dolina Ilkovicova 6, SK-84215 Bratislava, Slovakia
Slovak Acad Sci, Inst Geophys, Dubravska Cesta 9, SK-84528 Bratislava, Slovakia
Bernal Uruchurtu, Juan P.:
Univ Nacl Autonoma Mexico, Geosci Ctr, Juriquilla Blvd 3000, Queretaro 76230, Mexico
Puig, Teresa Pi:
Univ Nacl Autonoma Mexico, Geosci Ctr, Juriquilla Blvd 3000, Queretaro 76230, Mexico
Espinasa-Perena, Ramon:
Natl Disaster Prevent Ctr, Ctr Nacl Prevenc Desastres, Av Delfin Madrigal 665, Mexico City 04360, DF, Mexico
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