Episodic deformation at Changbaishan Tianchi volcano, northeast China during 2004 to 2010, observed by persistent scatterer interferometric synthetic aperture radar

Lingyun Ji,Yuan Wan,Jiandong Xu,Qingliang Wang

doi:10.1117/1.jrs.7.073499

Abstract

Based on ENVISAT ASAR images taken from 2004 to 2010, we obtain the deformation time series of the Changbaishan Tianchi volcano by using persistent scatterer interferometric synthetic aperture radar (PSInSAR) technique. Then, the magma chamber parameters are derived by modeling the PSInSAR deformation field based on a Mogi point source. We draw the following conclusions. First, the magma chamber is located immediately beneath the caldera, with a depth of 9 km below sea level. Second, the Changbaishan Tianchi volcano inflated between August 2006 and August 2008, which may be a result of an episodic magma intrusion event leading to pressurization and a volume increase of the magma chamber. The deformation pattern changed oppositely during August 2008 to June 2010, with maximum subsidence more than 10 mm, which may be caused by magma cooling and crystallization in the crustal chamber. Moreover, the deformation fields consist of several components, including large-scale deformation caused by magmatic activity, the local deformation caused by the active faults, and others. In conclusion, our results indicate that the anomalous activity of the Changbaishan Tianchi volcano is obvious in recent years, providing a basis for further research on monitoring this active volcano to reduce hazards and risks of future eruptions.

Highlights

The Changbaishan Tianchi volcano is a massive stratovolcano, located in the northeast of China, at the boundary between China and North Korea (Fig. 1)
Among all possible tracks covering the Changbaishan Tianchi volcano area, we focus on the descending track 146, which provides the largest number of suitable images for our analysis
Time series are rescaled to the first acquisition (i.e., May 28, 2004), being understood that the persistent scatterer interferometric synthetic aperture radar (PSInSAR) master image of the processing is the June 17, 2005, acquisition

Summary

Introduction

The Changbaishan Tianchi volcano is a massive stratovolcano, located in the northeast of China, at the boundary between China and North Korea (Fig. 1). Based on the previous study, Changbaishan Tianchi volcano has experienced several stages of explosive eruption in history especially during the latest 1000 years, in which the 946 AD eruption, the so-called millennium eruption, is considered as one of the largest eruptions in the world in the past 2000 years.[1,2] At least three eruptive activities occurred in AD 1668, 1702, and 1903 after the millennium eruption.[3] Due to these large explosive eruption events, Changbaishan Tianchi volcano is considered the most dangerous volcano in China. From 2002 to 2006, volcanic seismicity, ground deformation, volcanic thermal anomaly, and volcanic gas geochemistry increased, indicating the volcano has begun to wake after more than 100 years of inactivity.[2,4,5] The 2002 to 2006 volcanic unrest events attracted much attention from the Chinese government and volcanologists

Results

Discussion

Conclusion