2002 Jun 20 Cimarron County, Oklahoma Earthquakes

Origin time 12:14:18.0 UTC/GMT or 7:14:18.0 AM CDT, Latitude 36.542egrees N, Longitude 102.918degrees W

Depth 5.0 km, restrained, Magnitude 3.6 (mbLg scale)

This was the first earthquake in Cimarron County in 26 years. The only
known previous earthquakes in Cimarron Co. were a magnitude 2.1 and
a magnitude 2.7 on March 30, 1976. Cimarron County residents have felt
some earthquakes with epicenters outside their county. The magnitude 5.0
earthquake centered west of Oklahoma City in Canadian County was felt
in all Oklahoma Counties. The Canadian County earthquake occurred on 1952
April 9.

The 2002 June 19 Cimarron County earthquake had an epicenter 7.2 miles
west of Felt and 26 miles SW of Boise City. This is very near the point
where the borders of Oklahoma, Texas, amd New Mexico meet. The earthquake
was felt in Boise City and Keyes OK, Dalhart TX, and Clayton NM. 

Cimarron Co., OK earthquake 2002 Jun 19 The above shows P and S arrivals recorded near Leonard in Tulsa County. At Leonard there was one unusually large wave marked "Airy phase". The waves after S first arrives are like ripples on the surface of a pond, except that they are small (111 billionths of a meter) along the earth's surface rock. At this particular location, ripples (waves) of several frequencies added together to form one unusually large wave. In earthquake study, such a single large wave is called an "Airy phase". For ocena waves, a similar wave is called, at least in fiction writing, a "rogue wave". The Airy phase is expanded in the figure below.

THE OKLAHOMA GEOLOGICAL SURVEY HAS RECEIVED THE FOLLOWING FELT REPORTS BY WWW FORM PLUS SOME TELEPHONE REPORTS NOT YET SUMMARIZED: 1. Keyes, Cimarron Co., 73947: heard dishes rattle felt like someone bumped my chair. 2. Boise City, Cimarron Co., Court House Square, 73933: sounded like airplane breaking the sound barrier. felt more intense than that but very short lived shook court house. 3. Felt, Cimarron Co., South of Wheeless Church, 73933: In our home inside, ground floor, sitting down at my computer. Loud bang and house shook for maybe 15 seconds. I thought a big tree limb had fallen on the house but went outside and could see nothing. My wife was in bed in a distant part of the house and she said she thought it was an earthquake. We have no close neighbors (within 4 miles) and no one else we talked to 10 or 15 miles away felt or heard it. 4. Clayton, Union Co., New Mexico, 7 miles west of Luna Theatre and railroad on Springer Hwy, 88415: In living room. raised double-wide. Walking through the living room. At first I thought it was a jet flying down close and heard things rattle in the house. The ground shook, almost felt like loosing balance. Saw things in the house vibrating.1:wq 5. Boise City, Cimarron Co., 73933: I was lying in bed and it felt like someone bounced on the bed--there was a sudden jolt followed by a gentle shaking. I heard a faint rattling sound. 6. Boise City, Cimarron Co., 73933: 1st story sitting down, reading. I was sitting on my couch in my living room. I felt it move. I heard nothing, just felt the couch move. 7. Seneca, Union Co., New Mexico, 36.63 -103.26, 88415-0172: First story. I was sitting down, drinking cup of coffee. I first heard a roar, thinking it was one of those jets that overfly the area out here. Then felt my house "jump". A sharp "jolt". Went and turned off the sprinklers in case well had caved in. 8. Clayton, Union Co, New Mexico, S of First Baptist Church, 88415: Inside, single story. I was sitting in bed, my husband was shaving. heard: low rumble, bed shook, my husband said, "what was that? He thought someone was blasting somewhere? I told him I grew up in southern California, and that was no blasting, that was an earthquake, I would bet my life on that. felt: whole house shook. 9. Texline, Dallam Co., Texas, 4 miles south of oklahoma state line, on texas highway F.M. 296, 79022: first floor, standing in kitchen, making coffee. heard roof of house shake, the roof shook like the low flying fighter jets make except without the noise of their engines. Felt vibrations same as heard. 10. Dalhart, Hartley Co. (1block S of Dallam Co. line, 79022: In my den, first floor talking on the phone, sitting down. I heard a sharp cracking noise and thought something had hit the wall of my patio, and then the bed swayed and so did the floor. Loud sound. Pictures fell off the wall. Stuff fell off the shelf on the patio. My cat went into orbit and ran to hide. She had been nervous all afternoon (?) anyway. Small tremor about 2:00PM. in past I have felt momentary movement every now and then since about two or so years ago. 11. Clayton, New Mexico: At my dining room table. Heard a rumble and then a boom, and then the house started shaking. I could hear things rubbing gainst the walls. My dad told me he had felt a shake around 4:30AM. 12. Reported indirectly by 11. Half way between Folsom, New Mexico, and Kenton, Oklahoma.: Heard a lood boom and house shook. 13. Dalhart, Dallam Co., Texas, Cherry St., 790224: Laying in bed on first floor, bed moved. Heard nothing. 14. 25 miles south of Clayton, New Mexico, 2 miles west of the Texas state line, 88436: My headboard hit the wall. It was hard enough to wake me up.


Daily Seismograms of Worldwide earthquakes