To the stanford campus as well. Again, the walden area is mostly a neighborhood made up of lots of high rises and condos. But we did feel that people were saying that they really did feel what was like an initial shake and then some rolling after. Right here in the nbc newsroom we felt the initial shake. A fewle ros right after that. We knew right away, probably as all of you watching and listening to us, that it was an earthquake. Here are some of the numbers here, 10 33 p. M. , so about 30 minutes ago. It first was a 4. 5. It was upgraded, this happens pretty often, upgraded to a 4. 7 and back to a 4. 5 followed by an aftershock of at least a 2. 1. Lots going on this hour. Keir going to check through the area to see if there was any damage or injuries with this. We want to bring in sara minuteson of the usgs. Good evening, sara. We understand this happened on the concord green valley fault. Is that correct . Thats actually not clear at this point. It look like it may be off the green valley fault on some perhaps small unmapped fault. It looks to be sort of left of the concord fault. So besides the main faults in the area, there are lots of tiny faults that accommodate the strain on the main faults. Theyre physically so small that they are really only capable of hosting very small earthquakes. Sarah, thanks for your time. What did you see in terms of the usgs perspective in what this earthquake, how it happened in terms of the intensity, the magnitude and perhaps why the magnitudes changed there for the first few minutes. Well, in the minutes after an earthquake, the location of an earthquake get updated as Additional Data come in, and the source parameters of earthquake can be better refined. Its not uncommon for the magnitude to change a little and for the depth we appear to have lost sarah. Sarah, are you hearing us still . I hear you. Okay. Perfect. Im sorry, we lost you in that. I noticed that you said before that this seems to have happened on a smaller fault and you feel the intensity. Is that what you were explaining to us . You can feel it a little more dramatically when it happens on a smaller fault . Well, smaller magnitude earthquakes can, in fact, create intense shaking because they tend to radiate at high frequencies, which are very which are somehow felt better than more low frequencies that can be more like sea sickness. Okay. We get it. So youre saying that the kind of the abruptness of it was felt more mmmhmm. Because its along a why peoplre something which felt very dpr k dramatic to them because it happened so quickly with intensity. Yes. Okay. Sarah minson of the usgs, thanks for your time. Just to be clear, youre not re its perhaps an unmapped fault from your perspective. Thats what it appears to be at this time. The data is still coming in. Okay. Sarah, thank you. Well get back to you. We appreciate your time. If youre just tuning in, perhaps you felt it in the small area of walden, just north of walnut creek, 10 33 p. M. , the earthquake and then aftershocks. Lets bring in our chief meteorologist jeff ranieri. Weve been talking so specifically on the 30th anniversary of the loma quake. Youre doing indepth reporting on earthquakes. What are you seeing from that area . Well, just as we heard from the usgs expert, likely close to the green valley fault and the running through that area that could have relieved a little bit of that pressure tonight. I know down here in san jose we definitely felt it in our studio. Maybe eight to ten seconds of rocking back and forth, which i know a lot of you back home have felt. A 4. 5 four miles below the earths surface. Thats relatively shallow and why many of you did feel it this evening. What about aftershocks . This is live data coming in from the usgs. We had a 1. 6 coming in before that 4 p. 5 at 10 11. 10 23, we had the 2. 5. After the main earthquake we had another 1. 2 aftershock and a 1. 6. Safe to call this a swarm of earthquakes right now. Heres pleasanton. Theres walnut creek. Most of that activity, youre feeling it at home right here certainly in Pleasant Hill with your house continuing to shake. With that kind of a swarm that were seeing at the current moment, we likely could continue to see some smaller engines as we head into the overnight hours. We are of course not sure if this is a larger earthquake. I want a lot of you to start thinking about your flashlights, your batteries, your radios, what you would do if a larger earthquake were to hit. We dont want to cause any undue alarm, but with this kind of a swarm happening, it is something that comes to the front of our minds. Lets go ahead and bring this out wider. And what i want to take a look at here, we showed you the fault, is the shake intensity map. I want to show you immediately around the area as our computer loads up with the data. You can see this green ring right around the epicenter. Of course the source of the earthquake. Some pretty good moderate shaking there. Just outside of that it was light to moderate. And then, of course, most of the bay area did feel this shaking. So this rating on the mercalli shaking scale is once again considered moderate. Everyone in the area felt it. Unstable objects could have fallen off some of the walls. So remember to drop, cover and hold. Its the simplest advice. We can forget it. If we get a larger earthquake, you got to drop, cover and hold. You dont want to run out of a building. That is the way people get killed in earthquakes. Please think about your environment, where you ary just in case this was the foreshock to a larger earthquake. Thanks again, jeff. While you want to be prepared and that is wonderful information, it doesnt necessarily mean youre going to get a bigger one because we have a swarm. Weve seen swarms of earthquakes in danville clustered together which have unnerved people, and it has not produced a larger earthquake but we need to be prepared and ready for whatever comes next. Lets bring in mariana from san ramon. Youre right in that shake intensity area that jeff has just been talking about. Thank you for being with us. Tell us a little bit about what you felt. Well, extremely intense, id say. It actually felt like my house was being torn down. Ive felt earthquakes before, but this one was really, really intense. How long did it last for you . Just about 30 seconds to a minute. And absolutely no aftershocks. Thats strange that you had aftershocks in some areas and not others. I did a quick check of my house and my little alice in wonderland doll, small, fell down and a lamp fell down. A lamp was knocked over. Thats kind of scary when lamps fall over because you never know with electricity. All right. Marianne from san ramon, we appreciate your description there. What else . You said lamps fell down. Any other dishes or anything that kind of jumped off the counters . No. Id say a lamp and a doll. Okay. And the interesting thing is my dog didnt feel it at all. Usually animals feel it first. Okay. Well, we certainly hope that youre prepared let me clarify for you. Im a realtor so i really know this area very well. Waldon is not a town, its a subdivision. Like a neighborhood, right . A neighborhood, exactly. Thats good information. Thank you, marianne. Lets go now to nbc bay areas reporter Sharon Katsuda joins us in walnut creek, right next to waldon. Its raj and jessica. What did you feel . Hi, raj and jessica. Definitely the hanging light above our dining room was swinging when this happened. But i was in a very deep sleep when this happened. At 10 30 because as you know, i was supposed to go to work for the morning shift in a few hours. So i was in a deep sleep and it was enough to wake me up. And when i did, i still felt a lot of shaking for about ten seconds. Id say about five strong jolts. And it was enough for my daughter, my older high school daughter, who was studying, to run over and say, whats going on, whats going on . And shes everyones okay. My husband also ran from the living room very well aware of what was going on. And so everyones fine. Electricitys still on. No damage. But definitely felt it very strong here in walnut creek. Sharon, we felt the initial jolt here in the nbc newsroom here in san jose. I personally did not feel any aftershocks. Im assuming you felt some aftershocks in walnut creek . Thats interesting. I heard the previous caller. We did not either. Youve been getting reports of that. Ive been Walking Around after i called the newsroom and have not felt anything since that first earthquake. So, no, not here. Did you feel anything before . Litrding to jeff1. 6 one, e bit more and then at 10 23 there was a 2. 5 earthquake before you had that 10 33 one, which was the 4. 5. So you didnt feel anything before that one . Exactly, no. I was in a deep sleep. So it was enough, the main one, to wake me up, for sure. And im looking across the street. I see, you know, electricity still on with my neighbors home. My younger daughters just waking up right now saying, whats going on, mom . So obviously some people have felt it, you know, who were up. But not strong in huff to wake others up who are already sleeping, the youngsters. Okay. Thank you so much, sharon. We know youre going to be here bright and early in just a couple of hours. Thats right. Youll be reporting on this story. I have to sayn my house, i called my house. I live in pleasanton. I called my house and my daughter said she definitely felt it and yet, you know, other people that were sleeping didnt feel anything. Thats the thing. Thankfully its not over a 6. Usually anything under a 6 around here, most people feel it but sometimes people sleep right through it or dont feel it at all. Sharon, of course, in walnut creek felt it but didnt feel the aftershock. Its hit and miss. San jose people felt it. Peninsula, especially the east bay where this is centered. When jeff comes back, he was talking about a few hours ago today the magnitude versus the intensity. The magnitude is one thing and the intensity scales another thing. Its much more widespread. I did get a text from danville where they said they had photos fall off a bookcase and felt that intensity. Danville being very close, obviously, to walnut creek. Go ahead. We have someone else on the line. Daisy, are you from concord . Yes. Hi, daisy. Thanks you for calling in and talking to us. Tell us a little bit about what you felt. Oh, my rlly . It was such a big, huge jolt. My neighbor felt the same thing. So scary. Very alarming. But it was just that one jolt flash. I was on the couch with my cat. Didnt bother her but i was pretty alarmed. Okay. But youre okay . Did you see anything fall off the shelves or anything in your house or is everything okay . Just a pictured moved. Thats all. Okay. Daisy, we dont expect any major damage, but have you taken a peek outside to see if the powers on for the neighbors or any other activity outside . Oh, yeah, the powers on. Yes. All right. Thats good news. Powers on and nothing outside. Were checking with all the fire departments, all the hospitals to see if anythings offline for the local First Responders as well. Did you feel anything before or after, daisy . Not a thing. So that one big jolt is what you felt . Oh, yeah. It was terrifying. Im not kidding. Usually the rolling earthquakes, those dont seem to bother me. But this was just something out of nowhere. Okay. Well, stay safe and stay prepared. Thank you. Thank you, daisy. Thats daisy from concord. Lets bring in nbc bay area cheryl hurd who joins us from lafayette. Cheryl, you arrived on the scene. We see you there. We see the power on so were not expecting any major damage. So what did you feel and whats the response where you are . Reporter well, the power is on here, but i just checked with b. A. R. T. And b. A. R. T. Is running their trains at a reduced speed until a further notice. I jumped out the car and ran into matthew smith. Matthew says he felt the earthquake. He happens to live in lafayette. Matthew, what did you feel at the time . So i was brushing my teeth and the house jolted really abruptly and then we had a couple of little rippling feelings afterwards. It was pretty brief but a startling moment. So we went, checked to make sure everything was okay and that our youngest was still asleep. Reporter did anything fall from your shelves or any pictures move . The pictures went askew. A number of those we had to straighten. Just one toy fell from the shelves. Nothing really severe. So what did you think about this . Reporter it wasnt as bad as 89, which were all remembering these days, but, you know, it was definitely okay, yeah, were still in earthquake country. But you grow up here and go, okay, thats normal. Reporter all righty. Thanks for talking to us. So matthew is here. Possibly waiting for someone to get off this train. These trains are running at a reduced speed. We happen to be in alameda at the time. My photographer and i were sitting there editing our story and the car started shaking. I accused him of shaking the car. He says, im not doing that. So we dit felt it and things rolled on from there. Ive been getting calls from family in san jose. I even got a call from a viewer in santa rosa who says that he lives in an older home and his house felt like it was on roller skates. So everyone all over the bay area is feeling it, even mr. Smith here says i said, hey, did you feel the earthquake . And he says who didnt feel the earthquake . This quake has been felt far and wide. And theres a Police Officer well, there was a Police Officer here. He left. People are here waiting for the trains. It may be delayed, like i said. That the trains are running at a reduced speed right now. Back to you guys. Okay. Thank you very much, cheryl. Yeah, were hearing a lot of people talk about how they felt that jolt. It is a powerful reminder as we go into the 30th anniversary, which is on the 17th, that we do live in earthquake country. And i think a lot of times we get a little complacent and think, tal to people in danville who have been feeling swarms of earthquakes. They are a little more cognisant of this reality that we live in, but it is something that kind of falls by the wayside when you dont feel Something Like this. A couple of years since napa, which is the last time we really felt when we saw strong damage. This is the reminder that it can happen at any moment. It can. Danville area, the East San Jose foothills getting a lot of swarms in the last few months. There are a lot of us who feel a little tinglings. But tonight this was a bay areawide feeling for most of us getting this 4 pat. 5 magnitude 10 33. Lets get back to our phone lines. Tim, appreciate your time. So youre near the epicenter. Tell us what you felt at 10 33 p. M. No, i didnt just feel something, i heard a snap, pop, crack and then i started to feel a slight roll. Grabbed a sitting on the dresser so they didnt fall down. It seemed to have lasted a good 30 to 40 secondse. Circular aro good 10 to 15 feet in a circular motion. Good description. I believe that how long have you lived in the bay area. Seems like you know what youre talking about in terms of describing earthquakes . Yes, i do. Im an exreporter for a lot of local news and international news. And i just havent been doing it for a while, but im getting ready to, you know, ive been trained for the search program. So im going to be ready for the next one. But, yes, it was definitely a heavy duty shake. I heard from a friend of ours over in downtown martinez that it knocked him clear out of his bed. So, tim, youre just north of diablo valley college. Not far from the epicenter here. Do you feel any aftershocks . Were getting a mixed bag. Yes, i have some things that i havean purpose just to see. There is Slight Movement but nothing major. I can pretty much tell the area that we have there is a pool in that general area, and i was monitoring that. That seems it seems to keep moving. So im sure the aftershocks still happening. Like i said, i did hear a report out of santa rosa that was pretty heavy duty. Okay. All the way around. All right. We appreciate you taking the time to talk to us very much. We want to bring in our chief meteorologist jeff ranieri. Jeff, i know youve been back to worki working on your computer for get information. What have you learned . Since weve been hearing in these reports from these telephone calls, from viewers and also our shang was widespread. So we had that 4. 5 at 10 33 tonight. Just before that we didav few small shakers and after that we had certainly some very small aftershocks. So i wanted to get a look at the shake intensity map. This basically shows how far the shaking has traveled across the bay area and points beyond. And of course the focus is right there over concord, Pleasant Hill, walnut creek, mount diablo with moderate shaking. We had light even moderate shaking and the same thing down here to the south bay. Lets get you in closer. This is what people are reporting. The maps are lining up just with that. Some strong shaking right around mount diablo. Parts of Pleasant Hill. And close to walnut creek. So thats why your house was swaying back and forth with 4. 5 earthquake. That was rather shallow due to the strong shaking that is being shown on the shake intensity map. Lets put that on a scale. The shake intensity is part of the al the shaking we felt for most of the bay area was moderate. Some objects could fall. Strong shaking near mount diablo. We might find some furniture moved, even plaster in the walls might have cracks in it, which goes along with moderate to light shaking. You can see the aftershocks. We have primarily seen have been at a 2. 0 and lower over the past hour. But you can see how active it continues to remain right here around Pleasant Hill. So certainly a swarm of activity tonight. Were going to continue to track this. I just do want to reiterate that while this was a 4. 5, there is the chance this could be a foreshock to a larger earthquake. I dont want to alarm anyone, but just remember, drop, cover and hold. And if we do have a larger earthquake that happens, do not run out of a building. That is one of the number one ways that people do get killed during earthquakes. So its a great thing to think about your flashlights, your radio, everything you need to its dark outside. If we got a big earthquake, it would be hard to hurry up and get all that stuff you need. So think about that right now. Be safe. Ill continue to monitor those aftershocks. Jeff, just before you go, the south napa earthquake that we had in 2014 was a 6 the. 0, so significantly larger than this one. Between this is this the largest one i know im putting you dont know the spot that you can remember since that napa earthquake or have we had some bigger than this . I want to say we have had some earthquakes that have been slightly bigger than this. There is definitely a lot that goes into it when you have an earthquake on who is going to feel it. How deep are the earthquakes . Theyre anywhere from 4 to 8 miles below the surface. So theyre very shallow and what proximity are they to the population . This is a hea