Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Dynamic tilt correction using direct rotational motion measurements

Felix Bernauer, Joachim Wassermann and Heiner Igel
Dynamic tilt correction using direct rotational motion measurements
Seismological Research Letters (July 2020) Pre-Issue Publication

Abstract

Inertial sensors like seismometers or accelerometers are sensitive to tilt motions. In general, from pure acceleration measurements, it is not possible to separate the tilt acceleration from the translational ground acceleration. This can lead to severe misinterpretation of seismograms. Here, we present three different methods that can help solving this problem by correcting translational records for dynamic tilt induced by ground deformation with direct measurements of rotational motions: (1) a simple time-domain method, (2) a frequency-domain method proposed by Crawford and Webb (2000) using a coherence-weighted transfer function between rotation and acceleration, and (3) an adapted frequency-domain method that corrects only those parts of the spectrum with coherence between translational acceleration and rotation angle higher than 0.5. These three methods are discussed in three different experimental settings: (1) a reproducible and precisely known laboratory test using a high-precision tilt table, (2) a synthetic test with a simulated volcanic very-long-period event, and (3) a real data set recorded during the 2018 Mt. Kilauea caldera collapse. All the three test cases show severe influence of tilt motion on the acceleration measurements. The time-domain method and the adapted frequency-domain method show very similar performance in all three test cases. Those two methods are able to remove the tilt component reliably from the acceleration record.


ISSN: 0895-0695
EISSN: 1938-2057
Serial Title: Seismological Research Letters
Serial Volume: Pre-Issue Publication
Title: Dynamic tilt correction using direct rotational motion measurements
Affiliation: Ludwig-Maximilians Universitaet Muenchen, Department fuer Geo- und Umweltwissenschaften, Muenchen, Germany
Published: 20200708
Text Language: English
Publisher: Seismological Society of America, El Cerrito, CA, United States
References: 42
Accession Number: 2020-067276
Categories: Seismology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. sketch maps
N19°15'00" - N19°25'00", W155°19'60" - W155°04'60"
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2020, American Geosciences Institute. Abstract, Copyright, Seismological Society of America. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 202019
Close Modal

or Create an Account

Close Modal
Close Modal