Earth-prints repository, logo   DSpace

About DSpace Software
|earth-prints home page | roma library | bologna library | catania library | milano library | napoli library | palermo library
Please use this identifier to cite or link to this item:

Authors: Lewicki, J. L.*
Bergfeld, D.*
Cardellini, C.*
Chiodini, G.*
Granieri, D.*
Varley, N.*
Werner, C.*
Title: Comparative soil CO2 flux measurements and geostatistical estimation methods on Masaya volcano, Nicaragua
Title of journal: Bulletin of Volcanology
Publisher: Springer-Verlag
Issue Date: 2005
DOI: 10.1007/s00445-005-0423-9
Keywords: Carbon dioxide
Soil gas
Accumulation chamber method
Masaya volcano
Volcano monitoring
Emission rates
Abstract: We present a comparative study of soil CO2 flux ( ) measured by five groups (Groups 1–5) at the IAVCEI-CCVG Eighth Workshop on Volcanic Gases on Masaya volcano, Nicaragua. Groups 1–5 measured using the accumulation chamber method at 5-m spacing within a 900 m2 grid during a morning (AM) period. These measurements were repeated by Groups 1–3 during an afternoon (PM) period. Measured ranged from 218 to 14,719 g m–2 day–1. The variability of the five measurements made at each grid point ranged from ±5 to 167%. However, the arithmetic means of fluxes measured over the entire grid and associated total CO2 emission rate estimates varied between groups by only ±22%. All three groups that made PM measurements reported an 8–19% increase in total emissions over the AM results. Based on a comparison of measurements made during AM and PM times, we argue that this change is due in large part to natural temporal variability of gas flow, rather than to measurement error. In order to estimate the mean and associated CO2 emission rate of one data set and to map the spatial distribution, we compared six geostatistical methods: arithmetic and minimum variance unbiased estimator means of uninterpolated data, and arithmetic means of data interpolated by the multiquadric radial basis function, ordinary kriging, multi-Gaussian kriging, and sequential Gaussian simulation methods. While the total CO2 emission rates estimated using the different techniques only varied by ±4.4%, the maps showed important differences. We suggest that the sequential Gaussian simulation method yields the most realistic representation of the spatial distribution of , but a variety of geostatistical methods are appropriate to estimate the total CO2 emission rate from a study area, which is a primary goal in volcano monitoring research.
Appears in Collections:04.02.01. Geochemical exploration
04.08.07. Instruments and techniques
04.02.07. Instruments and techniques
Papers Published / Papers in press

Files in This Item:

File SizeFormatVisibility
Granieri.htm139.1 kBHTMLView/Open
springerlink.htm478 BHTMLView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Share this record




Stumble it!



Valid XHTML 1.0! ICT Support, development & maintenance are provided by CINECA. Powered on DSpace Software. CINECA