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Western Geophysical Party 75 and the Great Managua Earthquake of 1972

Story and Photos by MeI Weidner, originally published in the 1973 Spring Western Profile

Recounted by Scott Singleton

The Doodlebugger Diary recounts the experiences of geophysicists during their working lives. I’ve published extensively on my own experiences and encourage those of you with experiences of your own to also contribute. Your fellow industry professionals would love to hear your stories.

I’ve been occasionally reprinting a series of early 1980’s articles from the GSI Shotpoints and GSI Grapevine that can be found at I also have reprinted various Western Geophysical Profile articles. These can be found at The past two months I reprinted two stories of Western’s early boat-building escapades. This month I bring you an incredibly hair-raising story of the experiences of one particular field crew, having the bad luck of being in the wrong place at the wrong time, which of course is what all of us field types experienced at one point or another in our careers. Enjoy!

Prolog by Scott Singleton

The 1972 Nicaragua earthquake occurred at 12:29:44 a.m. local time on December 23 near Managua, the capital of Nicaragua. It had a moment magnitude of 6.3 and a maximum intensity of IX (Destructive). The epicenter was 28 km (17 mi) northeast of the city center and a depth of about 10 km (6.2 mi). Within an hour after the main shock, two aftershocks, one of magnitude 5.0 and the other 5.2, occurred at 1:18 a.m. and 1:20 a.m. The earthquake caused widespread casualties among Managua's residents: 4,000–11,000 were killed, 20,000 were injured and over 300,000 were left homeless. The earthquake destroyed 13 square kilometers (5.0 sq mi) in the city center. Much of the damage arose from ground movement which occurred within 10–15 seconds of the main shock.

This earthquake was accompanied by significant surface fault rupture. Examination of the fault scarp indicated a lateral motion to the northeast. Aftershock data revealed at least one of the faults extends from the surface to a depth of 8 to 10 kilometers beneath the city of Managua.

The aftereffects of this earthquake were substantial. Aid poured in from Mexico, the US, and other countries but the aid was not distributed well. It was later claimed that President Anastasio Somoza and his associates had used foreign aid for their own gain. Opposition to the regime, which had begun to surface before the earthquake, increased quickly among the lower classes and even among members of the upper and middle classes fed up with Somoza's corruption. This grew into a revolt that became the Nicaraguan revolution, in which Somoza was overthrown in 1979.

Because of the extent of the damage, the extent of the fault system beneath Managua, the misappropriation of aid, and the subsequent revolution and 11-year civil war, much of the city center remained ruined for almost 20 years. Reconstruction only began in earnest in the 1990s. (Source:

Figure 1

PROFILE Editor's Note:

Before Party 75 could get its scheduled Party Pickings report in from its then current base of operations, Managua, Nicaragua, an earthquake shook and ravaged that city. Its report then became an account of the experiences some of its personnel encountered during this great disaster and is presented here rather than in Party Pickings. (This is the second time in recent history that a crew was preparing Party Pickings when interrupted by a strong earthquake; the other crew was one in Alaska at the time of the Good Friday earthquake there in 1964. Not even such shattering and disastrous events as earthquakes can stop Westerners from reporting!) Our thanks go to Mel, the assistant and resident supervisor of Party 75, for his stories and photos and to Supervisor Ken Bryant for serving as liaison between Mel and the Profile.

Managua, Dec. 1972

AFTER Party 75 finished working on Lake Maracaibo in northern Venezuela, Captain Malcolm Leleaux and his crew took the Western Geophysical II to Panama and through the Panama Canal. Two of the seismic crew boarded the vessel there and rode to Corinto, Nicaragua. Also making the trip along the Pacific side of Central America were the cook and a helper.

Four of the seismic crew came to Managua, Nicaragua, from Panama City and Coordinator Jim Squires from Houston. Three others arrived from Ecuador and another from Mexico. This group then traveled the 100 miles north from Managua to Corinto to join the ship, marveling along the way at the smoking volcanoes and mountainous terrain between the two cities. Soon this unstable, volcanic belt was to have a special memory for members of the crew.

Fortunately, during the very early morning of Saturday, December 23, there were only eight members of the combined Western and navigation base station crews in the city of Managua. If more of us had been there, we would have had a much greater chance for casualties during the strong earthquake that struck the city that morning – an earthquake that virtually destroyed the city and killed several thousand of its population. Surprisingly, the only physical damage to any of our Party 75 personnel was one relatively minor ankle injury.

The first rumble occurred at 10:30 P.M. on Friday night while I was having dinner with Party Manager Hal Hanson and his wife Retha and three navigation base station personnel, Jim Price, his son Jimmie, and Dick Madison. Also present was an ex-Western employee now back on our payroll, R. C. Waits, who took movies of the later earthquake, which were shown on Houston television that same day. The first jolt was rather sharp; but, as tremors are common in the area, not much more than passing comment was made on it. After dinner we all went over to the Hansons' apartment for a short while, and then we all went home: the Prices to theirs next door and Dick Madison and I to the Hotel Balmoral in the center of the city.

Figure 9

As we were walking across the street from our parked car to the hotel entrance, the first strong jolt occurred at 12:30 in the morning. Buildings fell; signs fell; and the air was filled with dust. A large explosion occurred nearby, and in a very short time several blocks were burning and the sky glowed red. The car was covered with rubble; and we were covered with dust and small pieces of various materials, but we were both unhurt.

Dick and I decided to head for the Hanson and Price apartments. Normally it would have been a 10 minute walk, but it took us the better part of an hour to get there. Some streets were blocked by fallen buildings, and the creaking sounds of buildings not yet fallen made us avoid other streets. Surprisingly, we did not see any panic in the streets; most people were moving in a rather orderly manner toward the shore of Lake Managua and its surrounding open land.

When we arrived at the Hanson and Price apartments, we found both families alive and fairly well. The building had fallen down around the Hansons, trapping them inside, with Retha cutting and bruising her ankle rather badly; but Jim Price, after freeing himself and his son Jimmie from their place, had removed enough rubble and timbers to free Retha and Hal.

The Hansons lost everything they had and came out of it with only towels wrapped around them. Hal had just finished taking a shower, and Retha was