Map, faults and statistics

The map

The Map tab shows the events of the list, with the same filters. Each epicentre is a circle coloured and sized by magnitude; events from the last hour pulse. Circles too close together on screen merge into a cluster with the number of events: tapping it zooms into the area.

Tapping an event opens its details in a panel, at half or full height, while the map stays usable.

The buttons at the top:

• Recenter: goes back to the view of the chosen area (Italy, world, location or place);
• Map style: switches between the standard map and the hybrid satellite map;
• Faults and plates: shows or hides the tectonic data;
• on the right, MapKit’s location button.

At the bottom is the colour legend by magnitude.

Faults and plates

With Faults and plates on, the map draws:

• plate boundaries from the PB2002 model (Bird, 2003), with subduction zones dashed;
• active faults from the GEM Global Active Faults catalogue, coloured by type: Normal, Reverse, Strike-slip.

Faults appear only when zoomed in: while the map is too wide, the legend says Zoom in for faults. The data is built into the app, simplified for the map, and needs no connection. It shows where known faults are, not where an earthquake will happen.

Statistics

The Statistics tab sums up the area and period chosen in the list:

• tiles with Total events, Max magnitude, Mean magnitude, Mean depth, Events M ≥ 3 and Per day (average);
• Events per day, a bar chart;
• Magnitude over time, a point chart;
• Distribution by magnitude, the number of events per class;
• Strongest in this period, which open with a tap.

If the period has no events, the tab says so and stays empty.