Scientists had been warning us about this for decades. Aaaaand, as usual, most people didn't care much. Most people had no idea how to deal with it. Oh, sure, there are earthquakes all the time in LA. Get a five-pointer about once a year or two, and that'll get everybody interested for a couple of weeks. But they all had their daily lives to occupy them the rest of the time. Twenty million daily lives. It's a nearly incomprehensible number, especially now. So, it seems like almost nobody was expecting it when it happened, even though everybody was expecting it eventually.
On December 17th, 2027, at 12:36 pm, Southern California was obliterated.
[The USGS has prepared a number of videos of the scenario I am about to describe, which can be viewed here.]
The event began when the tiny town of Bombay Beach, on the eastern shore of the Salton Sea, exploded. The blast of seismic energy radiating out of the focus of the quake a mile and a half directly below lifted the entire town into the air, dropped it, and throttled apart whatever was left. The force of the rupture spread outward in all directions, then began to power northwest, along the edge of the sea. The fault rupture raced into the Coachella Valley, shredding apart Indio, Palm Springs, and everything in between, with twisting waves of rock and liquefied sand. As the earthquake continued along the line through the Banning Pass and into the San Bernardino Mountains, thousands of landslides began to pour downhill.
The temblor emerged from the mountains and plowed with full force into the city of San Bernardino, built right along the edge of the fault. The runways of the airport cracked, jumped, skewed apart. Houses collapsed into the shifting fault. High-rises built above a high water table sunk into the sandy swamp that flooded Downtown.
The seismic waves reached a wedge. The San Gabriel mountains split the geological bullet in half. The main rupture continued through the Cajon Pass into the Mojave desert, where it ate Victorville, and annihilated Lancaster and Palmdale, before finally stopping, after two hundred miles, in the Antelope Valley. The waves themselves continued on, splitting into the Santa Clarita Valley and Ventura, and roaring through the Tejon Pass and making a mess of Bakersfield. The first deflected waves bounced around the valleys of the Inland Empire before passing into the soft sediments of the San Gabriel Valley and the Los Angeles Basin, which always act more like jell-o than rock during a major temblor.
The resilient granite mountains surrounding the basin reflected and focused the earthquake's strongest force yet into the worst possible place. East Los Angeles, South Los Angeles, Watts, South Gate. The people of the Harbor Gateway cities, among the most thoroughly poor places in California, were enveloped in an apocalyptic nightmare of converging, redoubling crests of sand and rock, while homes, warehouses, freeways, and power lines twisted and disintegrated all around them. One older skyscraper in Downtown Los Angeles crumbled apart when a fissure opened beneath it, and nearly all the other towers shed their façades, but somehow remained intact structurally.
The waves continued through the West Side into Santa Monica, where towers built along bluffs crumbled onto the beach below. A landslide on the Palos Verdes peninsula sent a small tsunami across the channel to Catalina, where the Avalon waterfront was washed away...
All the major highways into Greater LA were cut apart where they crossed the faultline. High voltage electric transmission lines were downed across the region. Water, gas, and sewer lines were broken everywhere, spreading floods, fire, and disease.
In those three minutes, an estimated seventy-five thousand lives were lost. Over five million people were rendered permanently homeless, and all the rest left to struggle for their lives.
Refugees began to pour out of the region by the tens of thousands.
Until the siege.
National Guard and Army units were deployed at checkpoints in the mountain passes, at Camp Pendleton, and in Santa Barbara, in hopes of preventing unaffected cities from being swamped by the desperate homeless. The decision was made to attempt restore order to the region from the sea. The Navy's Amphibious landing ships would go ashore along Santa Monica Bay, bringing with them the needed medical supplies and food... and Martial Law.
This would prove a far greater disaster.
Next update: San Miguel Colony.
(And I promise that there will be no more walls of text like this!)