Section Three Cover – Events in formation of the "Bay of Los Angeles"
Here's where I decided to "explain" the geological history of the area and how I got
The first frame shows the "Pre-Impact" Los Angeles Basin. The shoreline actually is
Southern California's shoreline during the ice age when sea levels were a lot lower. I decided that this would have an effect on events.
It's hard to see, but the smaller legends there say (from top to bottom) "Santa Monica Mountains," "Ice Age Los Angeles River," "Ice Age Santa Monica Bay," and at the bottom "Catalina Island."
Second frame shows the impact. Note it throws up a ring of mountains around it that I had to fake on my previous two covers...
Third frame shows the basin at 20k years ago. Sea levels are still lower, so the crater actually doesn't directly connect to the sea. Instead, the L.A. River has filled it, creating what this ATL's geologists have called "Lake Los Angeles," a big freshwater lake. It's actually only a few dozen feet above (then) sea level, though, and it still outflows into ice age Santa Monica Bay, much like the pre-impact L.A. River did.
It's during this phase that much of the sediment is deposited in the crater, filling it in from it's initial depth of up to five hundred feet, to an average depth "then" of only fifty or sixty. By the current day, that average depth will be more like thirty...
Fourth frame shows the area at the end of the ice age. The sea levels are rising and between that and erosion, the ocean is breaking through the western side of the crater and into the Lake. Initially, this resulted in the lake going brackish, then the barrier pretty much collapsed and the former lake became an arm of the sea...
...which is what the fifth frame shows as the current day.