January 4, 1907 Earthquake: Gunungsitoli, Barus, NW Sumatra, Indonesia

Ref #414:

1907, Jan 4, 1907, 12:20 [local time]. There was an earthquake off the western coast of the northern part of Sumatra Island. At Gunungsitoli, undulating movements of the ground were so strong, it was impossible to stand. Great damage was done to structures everywhere. A crack formed in the cement floor of the customs office. At Barus, there were strong shocks in rapid succession; wooden buildings creaked; the concrete wall of the abandoned fortifications cracked. Strong tremors were felt at Rundeng, Pariaman, Airbangis, Natal, Siborongborong and Talu, where the wooden parts of the buildings creaked, cupboards were shifted, lamps swayed, and people felt nausea. Strong tremors were registered at Balig, Labuhanbilik, Bagansiapiapi, where an eyewitness felt dizzy, and at Tadjungbalai, where the pendulums of clocks stopped, lamps described circles with a radius of 30 cm, and the residents also felt dizzy. Reports about the earthquake came from Kualabeu, Sidikalang, where buildings shook and lamps swayed, and from Lubuksikaping and Shribudolok. Weak tremors were reported from Sibolga, Pajakumbu and Pulu Pandjang. A rumble was heard at many places (Kualabeu, Barus, Tandjungbalai, Sibolga and others). Less strong foreshocks were felt at a number of places at 2:00, 9:00 and 12:00. A tsunami arose.

Gutenberg, Richter (1954): 4.I; 5h19.2m; 2oN., 94.5o E.; 50 km; M=7.6. [The instrumental data about the earthquake are in poor agreement with the macroseismic data.]

Ref #88:

1907, Jan 4, 05:19:29 UTC, 2N, 96.3E, shallow depth, magnitude 7.8.

Ref #7135:

Yesterday's strange phenomenon witnessed on the south coast of Ceylon is explained as anticipated, by the fact of a big earthquake having occurred, which was recorded on the seismograph at the Technical College. On inquiry of Mr. Human our representative was informed that the instrument recorded a severe disturbance at 10:35 a.m., Indian standard time. The seismograph was disturbed for three hours, the oscillations of the pendulum exceeded the limits of the paper strip on which its movements are photographically recorded. The time elapsed from first tremors until the large earth waves was seven minutes, which is taken to indicate that the source of the disturbance is not far away from Ceylon. However, that indication is not an infallible guide in the case of severe disturbances, for in the case of the violent earthquakes which occurred in South America last August the records showed a much more sudden disturbance of the seismograph in Colombo than would be expected when the distance traveled by the waves is taken into account. But in the present instance, when there is the additional evidence of a disturbance of the sea along the south coast of Ceylon, it is tolerably safe to suppose that the source of the disturbance is not far away, and that it must have been submarine. Looking at the map of seismic regions it is probable that the source was either the deep pocket in the bed of the ocean called Wharton Deep, or a high ridge which extends under the sea along a line approximately joining Bombay and Mauritius. Wharton Deep is southeast of Colombo and is, in round numbers, 2000 to 2500 miles away. If it be true that the disturbance of the sea observed at Galle and Hambantota was not marked enough at Colombo to produce any comment, that evidence would point to the source being southeast or east of Ceylon, and Wharton Deep is the most likely spot. It is a curious fact, however, that no earthquake of importance has occurred in Wharton Deep up to the year 1903 since the date-1899-when regular observations of these disturbances have been recorded, whereas in the region which includes the submarine region of the southwest and west of Ceylon as many as 17 very large earthquakes occurred between 1899 and 1903.

Ref #10476:

1907, Jan 4, 05:19:13.18 UTC, 2.681N, 95.53E, magnitude 8.2 Mw.