30:T4cf,fig2 = html`

${ak_map}

What happened last month underneath Alaska?

Click the buttons to find out...

${d2s}

${all}

With only one month of earthquake data from the USGS, you can see subduction of the Pacific tectonic plate as it migrates north, plunging underneath the North American plate. Each dot is a quake, and you can see a band of subsurface quakes getting deeper toward the northwest. Near-surface quakes blossom like a flower across the entire state. These earthquakes occur along plate boundaries known as the Aleutian Megathrust and the Yakutat Block. Note: You can interact with the map by dragging the brush on the scatterplot (below) with your mouse or finger.

`31:[] 2e:{"title":"Alaska quakes","cells":[{"id":0,"value":"# Alaska quakes","pinned":false,"hidden":false,"mode":"md"},{"id":88,"value":"$30","pinned":false,"hidden":false,"mode":"ojs"},{"id":128,"value":"viewof ak_brush = viewof chart","pinned":false,"hidden":false,"mode":"ojs"},{"id":34,"value":"## the earthquakes","pinned":false,"hidden":false,"mode":"md"},{"id":36,"value":"geojson = {\n const url = \"https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_month.geojson\"\n const geojson = await d3.json(url);\n geojson.features = geojson.features.filter(d => d3.geoDistance([-152, 63], d.geometry.coordinates) < .3)\n return geojson;\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":451,"value":"## the map","pinned":false,"hidden":false,"mode":"md"},{"id":71,"value":"ak_map = {\n return Plot.plot({\n projection: {\n type: \"azimuthal-equidistant\",\n rotate: [152, -63],\n domain: ak,\n },\n width: width / 2,\n marks: [\n globe,\n Plot.geo(chart[2].map(d => d[2]), {r: 1, fill: \"#000\"}),\n ],\n });\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":461,"value":"## the buttons","pinned":false,"hidden":false,"mode":"md"},{"id":133,"value":"d2s = Inputs.button(\"Deep-to-surface transition\", {reduce: viewof chart.deep_to_surface})","pinned":true,"hidden":false,"mode":"ojs"},{"id":465,"value":"all = Inputs.button(\"All the quakes\", {reduce: viewof chart.all_of_them})","pinned":true,"hidden":false,"mode":"ojs"},{"id":9,"value":"## appendix","pinned":false,"hidden":false,"mode":"md"},{"id":124,"value":"import {viewof chart} with {geojson as geojson} from \"@pbogden/brush-w-transition\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":295,"value":"ak = stateShapes.features.filter(({id}) => id == \"02\")[0]","pinned":true,"hidden":false,"mode":"ojs"},{"id":289,"value":"import {stateShapes} from \"@observablehq/us-geographic-data\"","pinned":true,"hidden":false,"mode":"ojs"},{"id":233,"value":"globe = {\n const ids = ['124', '840', '643']; // Canada, US, Russia\n const countries = world50m.objects.countries.geometries.filter(({id}) => ids.includes(id))\n const world = topojson.feature(world50m, {type: \"GeometryCollection\", geometries: countries})\n return Plot.marks([Plot.graticule(), Plot.geo(world, {fill: \"#ccc\"}), Plot.sphere()])\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":219,"value":"import {world50m} from \"@visionscarto/geo\"","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W31","stdlib":"1","titling":"auto"}