A Seismic Insight – From Micro Tremors to Civic Awareness
🌍 Earthquake Blog
🖋️ Author: Prof. Dr. Ali Osman Öncel
📅 Date: July 2025
🌐 Topic: Tectonic Reality, Public Awareness, and Citizen Engagement
📚 Contents
- 📌 Basic Earthquake Data: Key metrics about the quake such as magnitude, location, depth, and nearby settlements.
- 🧭 Tectonic Setting and the Bird Model: Explanation of the tectonic context using Bird (2003) plate boundary model.
- 🔁 Aftershock? Gardner & Knopoff Analysis: Analysis of whether this quake is an aftershock based on time-distance criteria.
- 🧑🔬 Citizen Seismologists' Contributions: How citizen reports via EMSC contributed to intensity maps and awareness.
- 🏙️ Intensity Distribution by Districts: Variation of shaking intensity across districts and factors affecting it.
- 📈 Distance–Intensity Graph and Interpretation: Graphical analysis showing intensity decay with distance and anomalies explained.
- 🧠 Earthquake Clusters and Psychological Impact: Seismic clustering and public psychological response insights.
- 🏛️ Governance and Public Expectation: The gap between data reporting and action by authorities.
📌 Basic Earthquake Data
- Magnitude: Mw 4.0
- Coordinates: 40.844°N – 28.276°E
- Depth: 9 km
- Date & Time: July 5, 2025 – 14:24 (local time)
- Nearby Settlements: Esenyurt (39 km), Büyükçekmece (33 km)
🧭 Tectonic Setting and the Bird (2003) Model
According to the Bird (2003) plate boundary model, this earthquake occurred within the Kumburgaz Basin, located just north of the Eurasia–Anatolia plate boundary and near the transform-type North Anatolian Fault Zone. Micro-segment level stress releases in this region provide valuable scientific data.
🔁 Aftershock? Gardner & Knopoff Approach
Based on Gardner & Knopoff (1974) time–distance window, this tremor occurred 73 days after the Mw 6.2 mainshock on April 23, 2025, and approximately 35 km away. According to parameters, it can be classified as an aftershock.
🧑🔬 Citizen Seismologists' Contributions
Many people reported feeling the tremor through the EMSC app. Thanks to “citizen seismologist” participation, micro-scale intensity distribution maps have been produced.
🏙️ Intensity Distribution by Districts
- European Side: Esenyurt (MMI IV–V), Beylikdüzü (IV), Büyükçekmece (V)
- Asian Side: Kadıköy and Ümraniye (MMI I–II)
Ground differences and building characteristics directly affect this variety of felt intensity.
Why does intensity vary across different districts in the same city?
📈 Distance–Intensity Graph and Interpretation
The red line shows intensity decreasing with distance, while some points reach MMI VIII level. These anomalies can be explained by:
- Building characteristics
- Ground types
- Directionality of the seismic waves
🧠 Earthquake Clusters and Societal Anxiety
Earthquake records from 1965 to 2025 reveal this area is loaded with repeated quakes. The public narrative is:
“This time 4.0, but what if it’s 6.8?”
DYFI distributions reveal not only physical but also psychological sensitivity points.
🏛️ Governance: From Data Contribution to Action
Citizens report, scientists analyze; yet the real expectation is:
“Are these data reflected in local government plans?”
“Did any district governor or municipality see this data?”
Data should not only be collected but converted into effective action strategies.
For citizens reporting earthquakes: “If this earthquake were Mw 6.8, how many of today's reporters would be in risky buildings?”
Comments
Post a Comment