  We evaluated the body wave attenuation parameter in Kopili region of
northeast India. Using the modified algorithm of coda normalization method, we
delineated frequency-dependent attenuation for both P and S waves. Taking more
than 300 seismograms as input, we comprehensively studied microearthquake
spectra in the frequency range of 1.5 to 12 Hz. The estimated values of
$Q_P^{-1}$ and $Q_S^{-1}$ show strong frequency dependence. The relationships
emerge to be $Q_P^{-1}=(23.8\pm 6)\times10^{-3}f^{-1.2\pm 0.008}$ and
$Q_S^{-1}=(10.2\pm 2)\times10^{-3}f^{-1.3\pm 0.02}$, respectively. The ratio
$Q_P^{-1}/Q_S^{-1}$ is found to be larger than unity for the entire frequency
band which implies profound seismic activity and macroscale heterogeneity
prevailing in the region. The study may act as the building block towards
determination of source parameter and hazard related studies in the region.
