Electrical Resistivity Structure of Changbai Volcanic Mountain - Results from Magnetotelluric Exploration Methods

Gengen Qiu, Hui Fang, Jie Zhang, Fagen Pei, Qingyin Lv, Yan Peng

2018

Abstract

To address the foreign media’s comments that the Tianchi Volcano in Changbai Mountain is likely to erupt in the near future, we collected a magnetotelluric (MT) observation profile approximately 120 km in length in the area to detect the deep electrical structures of magma chamber. Because electromagnetic noise from an unknown source is very strong in the research area, we used remote-referencing and robust processing, rhoplus analysis, impedance tensor decomposition, and a mutual approximate calculating method between apparent resistivity and phase for MT data processing . These techniques resulted in relatively reliable electromagnetic response data in the strong electromagnetic noise area. The results show that there is a clear magma channel beneath Tianchi Volcano, at a depth of approximately 10 km. An obvious abnormal body of low resistance, where resistivity is less than 10 Ω•m connects with the magma channel at 7 km deep and north of the existing crater, suggesting a developing magma chamber in the shallow surface. There are two nearly vertical low resistivity zones at 7-17 km in depth, one between stations C07-C09 and the other between stations C04-C05, that connect directly to the low resistance body directly; these low resistivity zones are likely active fault zones. Crustal low resistivity anomaly bodies are widely developed at depths of 13 – 30 km about 20 km south of Tianchi Volcano, suggesting an active magma chamber. The MT sounding method results indicate that Changbai Mountain has a high risk of volcanic eruption, and the MT method performed well detecting the state of current volcanism.

Paper Citation

in Harvard Style

Qiu G., Fang H., Zhang J., Pei F., Lv Q. and Peng Y. (2018). Electrical Resistivity Structure of Changbai Volcanic Mountain - Results from Magnetotelluric Exploration Methods.In Proceedings of the International Workshop on Environment and Geoscience - Volume 1: IWEG, ISBN 978-989-758-342-1, pages 344-352. DOI: 10.5220/0007430203440352

in Bibtex Style

@conference{iweg18,
author={Gengen Qiu and Hui Fang and Jie Zhang and Fagen Pei and Qingyin Lv and Yan Peng},
title={Electrical Resistivity Structure of Changbai Volcanic Mountain - Results from Magnetotelluric Exploration Methods},
booktitle={Proceedings of the International Workshop on Environment and Geoscience - Volume 1: IWEG,},
year={2018},
pages={344-352},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0007430203440352},
isbn={978-989-758-342-1},
}

in EndNote Style

TY - CONF

JO - Proceedings of the International Workshop on Environment and Geoscience - Volume 1: IWEG,
TI - Electrical Resistivity Structure of Changbai Volcanic Mountain - Results from Magnetotelluric Exploration Methods
SN - 978-989-758-342-1
AU - Qiu G.
AU - Fang H.
AU - Zhang J.
AU - Pei F.
AU - Lv Q.
AU - Peng Y.
PY - 2018
SP - 344
EP - 352
DO - 10.5220/0007430203440352