Introducing a New Method in Data Visualization: Stress Filed Mapping in the Zagros Makran Transition Zone, Southern Iran

Document Type : Research Article

Author

Assistant Professor, Seismology Group, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran

Abstract

In this study, a new method is introduced for visualizing the vector data for the first time. This method is based on RGB attributing each rectangular cell within a grid with a specific square mesh size. Two different quantities are introduced, namely unidirectional and bidirectional, which will be illustrated using the two color circle types 1 and 2 as color scales. Seeking the correct illustration of the directions with a color scale, the opposite directions (SHmax) should be of the same color, making the problem more sophisticated so that the usual color wheel cannot be used. As an example, the SHmax variations in the Zagros Makran transition zone was mapped by using this new approach. Maximum horizontal stress directions are extracted from available earthquake focal mechanism data. The results show important variations in SHmax direction, which reflect the complicated tectonic environment of the study area. Several anomalies in the direction of SHmax are observed in the study area for the first time by implementing the proposed new method. Some of the anomalies take place in the areas where deeper earthquakes occur. This may imply the decoupling between the shallow seismogenic zone within the sedimentary cover and the crystalline basement, responsible for deeper events.

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References

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Journal of Seismology and Earthquake Engineering
Volume 23, Issue 4
November 2021
Pages 1-14

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