High-Frequency Noise at BFO

Vertical component, high-frequency noise at BFO is mainly of cultural origin. This can be seen very clearly in a time-frequency plot of the vertical component data of the STS-2 Seismometer. ( color, 4.7 Mb ) or ( b/w, 2.9 Mb ). The origin of this cultural noise is not known in detail but we suspect nearby (5 km) saw mills.

PSD levels for a quiet interval (late Saturday night - early Sunday morning) is shown here. The frequency-proportional increase in noise level above 12 Hz is probably due to the quantization noise of the Quanterra Q-680.