Where I live (Toronto), we don't have earthquakes, generally. We had a 5.0 in 2010 and a 5.1 in 2013, and those are the only earthquakes of mention in anyone's memory. I don't plan for earthquakes, or tornadoes (we do get those), or floods, or anything specific. I have general emergency plans, which should see me through a week or so after any major emergency. The worst of our disasters here are multi-day power outages. We had one last winter (some know the occurence as the polar vortex). We got hit hard enough that we were without power for three days. It happened also during the Great Blackout of 2003. Beyond that, I've only seen a single tornado, and a pretty bad flood. While I can't speak for everywhere on Earth, I've found that communites tend to band together in disasters. Looting and pillaging is rarely a concern (or maybe I'm just Canadian).
The most important thing to keep around in an emergency (and bear in mind that most "emergencies" last only for a few days to a week) is toiletries, and personal cleaning supplies. We have a supply of soap, toothpaste, and toilet paper in the first aid kit. We keep enough probably for five families. After that, a means of communication is esserntial. Cellphones cannot be relied on in an emergency, although from experience, they do actually work - they worked fine in both the 2003 and 2013 blackouts here - but I just don't trust them, even if only because batteries run dead and I can't guarantee a way to charge it, especially in winter. I have a couple of old rotary phones around and have always kept a landline, just in case these things happen (and as it happens, we're frequently the only household in the neighbourhood with a functional phone in a power failure).
My military survival training taught me there are five basic survival needs, in any situation, those being 1) first aid 2) shelter 3) fire 4) water 5) food, in that order. In an urban environment I would also add communications and sanitation to that list.
Here's what I do:
Food is a commonly misconcieved need in an emergency. It is dead last on my list of survival necessities, as I know I can survive about three weeks without food, if I keep my activity levels low. That being said however, I do have approximately a weeks' worth of food in the pantry at all times (not for emergencies, but mainly because we like having a large selection of foodstuffs at all times), which obviates the need for a primary emergency food source. I'm also an avid wilderness canoeist, and usually keep about a months' worth of IMP's (Canadian MRE's, but taste better) in storage which gets cycled probably around every 10 years. So I'm good for food.
Again, this need is commonly placed too high on a survival needs list. You can survive three days without water. We have freshwater streams running through town which could make a suitable source of water in an emergency (though not in winter, and it wouldn't be enough for my whole town). There is always 200 litres in the hot water tank as well. Water is bulky, heavy, and outdoor storage is impossible here as it would freeze. Much more important is a method of purifying what water you can readily find elsewhere. We keep silver nitrate, water purification tablets, large quantities of bleach, and two pump action water filters on hand, just in the camping gear, plus the campstove can be used to boil it.
I go camping a lot, so extra tents are not a concern, nor are tarps, should our house be destroyed or sufficiently damaged. We have enough that we could easily house others if the need was there.
I have two or three campstoves, plus a barbecue, so there's not too much concern there. All my campstoves use readily available fuel sources (mostly kerosene), and can also operate on gasoline or diesel oil with a few minor midification if needed. One can also run on propane or butane or LP gas as well.
We have a very well stocked first aid kit, which aside from the obvious bandages, alcohol, peroxide, and tensor bandages, also contains silver nitrate sticks, collapsible splints, two courses of antibiotics, narcotic painkillers, surgical needles and thread, and lidocaine. We also keep the emergency supply of tampons and pads in there, which are useful for a great many things besides the obvious (however still very important to have around in a disaster for their intended purposes)
What I don't have is an emergency radio, or the ability to recharge batteries if the power fails, which it most likely will in a disaster, or a gas generator, however I imagine gasoline supplies would run out in any major emergency - that's been my experience, anyway.