Surface-wave tomography for mineral exploration: a successful combination of passive and active data (Siilinjärvi phosphorus mine, Finland)
-
Published:2022-03-01
Issue:2
Volume:13
Page:417-429
-
ISSN:1869-9529
-
Container-title:Solid Earth
-
language:en
-
Short-container-title:Solid Earth
Author:
Colombero ChiaraORCID, Papadopoulou Myrto, Kauti Tuomas, Skyttä Pietari, Koivisto Emilia, Savolainen Mikko, Socco Laura ValentinaORCID
Abstract
Abstract. Surface wave (SW) methods offer promising options for an
effective and sustainable development of seismic exploration, but they still
remain under-exploited in hard rock sites. We present a successful
application of active and passive surface wave tomography for the
characterization of the southern continuation of the Siilinjärvi
phosphate deposit (Finland). A semi-automatic workflow for the extraction of
the path-average dispersion curves (DCs) from ambient seismic noise data is
proposed, including identification of time windows with strong coherent SW
signal, azimuth analysis and two-station method for DC picking. DCs
retrieved from passive data are compared with active SW tomography results recently
obtained at the site. Passive data are found to carry information at longer
wavelengths, thus extending the investigation depth. Active and passive DCs
are consequently inverted together to retrieve a deep pseudo-3D shear-wave
velocity model for the site, with improved resolution. The southern
continuation of the mineralization, its contacts with the host rocks and
different sets of cross-cutting diabase dikes are well imaged in the final
velocity model. The seismic results are compared with the latest available
geological models to both validate the proposed workflow and improve the
interpretation of the geometry and extent of the mineralization. Important
large-scale geological boundaries and structural discontinuities are
recognized from the results, demonstrating the effectiveness and advantages
of the methods for mineral exploration perspectives.
Funder
European Commission
Publisher
Copernicus GmbH
Subject
Paleontology,Stratigraphy,Earth-Surface Processes,Geochemistry and Petrology,Geology,Geophysics,Soil Science
Reference30 articles.
1. Abbiss, C. P.: Shear wave measurements of the elasticity of the ground,
Geotechnique, 31, 91–104, https://doi.org/10.1680/geot.1981.31.1.91, 1981. 2. Boiero, D.: Surface wave analysis for building shear wave velocity models,
PhD Thesis, Politecnico di Torino, Torino, Italy, 2009. 3. Bussat, S. and Kugler, S.: Recording noise – Estimating shear-wave
velocities: Feasibility of offshore ambient-noise surface-wave tomography
(answt) on a reservoir scale, SEG Technical Program Expanded Abstracts 2009,
1627–1631, https://doi.org/10.1190/1.3255161, 2009. 4. Colombero, C., Comina, C., and Socco, L. V.: Imaging near-surface sharp
lateral variations with surface-wave methods – Part 1: Detection and
location, Geophysics, 84, EN93–EN111, https://doi.org/10.1190/geo2019-0149.1, 2019. 5. Da Col, F., Papadopoulou, M., Koivisto, E., Sito, Ł., Savolainen, M., and
Socco, L. V.: Application of surface-wave tomography to mineral exploration:
A case study from Siilinjärvi, Finland, Geophys. Prospect., 68,
254–269, https://doi.org/10.1111/1365-2478.12903, 2020.
Cited by
5 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|