English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/168153
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Origin of abundant moonmilk deposits in a subsurface granitic environment

AuthorsMiller, A. Z. ; García-Sánchez, A. M. ; Martin-Sanchez, Pedro Mª; Costa Pereira, Manuel F. ; Spangenberg, Jorge E. ; Jurado, Valme ; Dionísio, A.; Alfonso, María José ; Iglé Sias Chaminé, Helder I. ; Hermosín, Bernardo ; Sáiz-Jiménez, Cesáreo
carbonate precipitation
Needle-fibre calcite
Issue DateAug-2018
PublisherJohn Wiley & Sons
International Association of Sedimentologists
CitationSedimentology 65(5) 1482-1503 (2018)
AbstractSubsurface granitic environments are scarce and poorly investigated. A multi‐disciplinary approach was used to characterize the abundant moonmilk deposits and associated microbial communities coating the granite walls of the 16th Century Paranhos spring water tunnel in Porto city (north‐west Portugal). It is possible that this study is the first record of moonmilk in an urban subsurface granitic environment. The morphology and texture, mineralogical composition, stable isotope composition and microbial diversity of moonmilk deposits have been studied to infer the processes of moonmilk formation. These whitish secondary mineral deposits are composed of very fine needle‐fibre calcite crystals with different morphologies and density. Calcified filaments of fungal hyphae or bacteria were distinguished by field emission scanning electron microscopy. Stable isotope analysis revealed a meteoric origin of the needle‐fibre calcite, with an important contribution of atmospheric CO2, soil respiration and urn:x-wiley:00370746:media:sed12431:sed12431-math-0001 from weathering of Ca‐bearing minerals. The DNA‐based analyses revealed the presence of micro‐organisms related to urban contamination, including Actinobacteria, mainly represented by Pseudonocardia hispaniensis, Thaumarchaeota and Ascomycota, dominated by Cladosporium. This microbial composition is consistent with groundwater pollution and contamination sources of the overlying urban area, including garages, petrol stations and wastewater pipeline leakage, showing that the Paranhos tunnel is greatly perturbed by anthropogenic activities. Whether the identified micro‐organisms are involved in the formation of the needle‐fibre calcite or not is difficult to demonstrate, but this study evidenced both abiotic and biogenic genesis for the calcite moonmilk in this subsurface granitic environment.
Description22 páginas.-- 6 figuras.-- 115 referencias.-- Additional Supporting Information may be found in the online version of this article: http://dx.doi.org/10.1111/sed.12431
Publisher version (URL)http://dx.doi.org/10.1111/sed.12431
Appears in Collections:(IRNAS) Artículos
Files in This Item:
File Description SizeFormat 
Origin_abundant_moonmilk_deposits_2018_Postprint.pdf3,3 MBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.