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Tectonic setting of the Bird Head Papua Island becomes an important model for petroleum system in Eastern part of Indonesia. The current exploration has been started since the oil seepage finding in Bintuni and Salawati Basin. The biogenic gas in shallow layer turns out to become an interesting issue in the hydrocarbon exploration. The hydrocarbon accumulation appearance in a shallow layer with dry gas type, appeal biogenic gas for further research. This paper aims at delineating the sweet spot hydrocarbon potential in shallow layer by applying the spectral decomposition technique. The spectral decomposition is decomposing the seismic signal into an individual frequency, which has significant geological meaning. One of spectral decomposition methods is Continuous Wavelet Transform (CWT), which transforms the seismic signal into individual time and frequency simultaneously. This method is able to make easier time-frequency map analysis. When time resolution increases, the frequency resolution will be decreased, and vice versa. In this study, we perform low-frequency shadow zone analysis in which the amplitude anomaly at a low frequency of 15 Hz was observed and we then compare it to the amplitude at the mid (20 Hz) and the high-frequency (30 Hz). The appearance of the amplitude anomaly at a low frequency was disappeared at high frequency, this anomaly disappears. The spectral decomposition by using CWT algorithm has been successfully applied to delineate the sweet spot zone.

Nonlinear dynamics induced by seismic sources and seismic waves are common in Earth. Observations range from seismic strong ground motion (the most damaging aspect of earthquakes), intense near-source effects, and distant nonlinear effects from the source that have important consequences. The distant effects include dynamic earthquake triggering—one of the most fascinating topics in seismology today—which may be elastically nonlinearly driven. Dynamic earthquake triggering is the phenomenon whereby seismic waves generated from one earthquake trigger slip events on a nearby or distant fault. Dynamic triggering may take place at distances thousands of kilometers from the triggering earthquake, and includes triggering of the entire spectrum of slip behaviors currently identified. These include triggered earthquakes and triggered slow, silent-slip during which little seismic energy is radiated. It appears that the elasticity of the fault gouge—the granular material located between the fault blocks—is key to the triggering phenomenon.

The new approach method to determine the magnitude by using amplitude displacement relationship (A), epicenter distance (Δ) and duration of high frequency radiation (t) has been investigated for Tasikmalaya earthquake, on September 2, 2009, and their aftershock. Moment magnitude scale commonly used seismic surface waves with the teleseismic range of the period is greater than 200 seconds or a moment magnitude of the P wave using teleseismic seismogram data and the range of 10-60 seconds. In this research techniques have been developed a new approach to determine the displacement amplitude and duration of high frequency radiation using near earthquake. Determination of the duration of high frequency using half of period of P waves on the seismograms displacement. This is due tothe very complex rupture process in the near earthquake. Seismic data of the P wave mixing with other wave (S wave) before the duration runs out, so it is difficult to separate or determined the final of P-wave. Application of the 68...

This paper evaluates the response of the seven‐story instrumented building, Holiday Inn Hotel, during the 1994 Northridge earthquake through the wave propagation dynamic analysis. The building has been instrumented during other earthquakes, the most important of these was the 1971 San Fernando earthquake, where the building was located only 22 [km] from the epicenter and didn't showing structural damage. From the accelerograms analysis is detected the propagation of Rayleigh and soil waves in the building, where the first has a polarized particle motion on a vertical plane and the second has a coupled particle motion in the horizontal plane. Both waves impose their frequencies to the building response, whose fundamental frequency (1.4 [Hz] according to ambient vibration test) is less than the frequencies of the identified waves. Due to the impact that these observations have in the seismic design of buildings, as a first attempt, a simple method is proposed to estimate the drift produced by the propagation of a Rayleigh wave in buildings.

Model experiments have done in the anechoic chamber of the Ecole Centrale de Lyon in order to investigate long range propagation of short duration N‐waves under various configurations. Measurements have been done in a free field configuration and in the shadow zone created by a curved surface. The surface was either smooth or rough.

Propagation paths of Saturian Kilometric Radiation (SKR) are determined using ray tracing computations and results are compared with those obtained by the Voyager 1 Spacecraft. For the computation of ray paths ionospheric model similar to that suggested by Galopeau et al. (1989) has been used which includes both the ionospheric as well as torus densities. A dipole magnetic field is assumed. The Source location are assumed between 0–3 Rs (Saturnian radii) along the field line of 75 degree North and the initial wave normal angle are assumed to be field aligned. The computer program used is similar to that of Shawhan (1967). The ray paths are computed for different frequencies of the SKR in the range of 3 kHZ–1 MHz.The result shows that the lowest frequencies are refracted more than the higher frequencies from the torus and effect diminishes with increasing frequencies. This explains the existence of the shadow zone near the equator as seen in the observations of SKR. Further, the results also explain the spectral characteristics of the SKR. The effect of Dione control is thoroughly discussed.Propagation paths of Saturian Kilometric Radiation (SKR) are determined using ray tracing computations and results are compared with those obtained by the Voyager 1 Spacecraft. For the computation of ray paths ionospheric model similar to that suggested by Galopeau et al. (1989) has been used which includes both the ionospheric as well as torus densities. A dipole magnetic field is assumed. The Source location are assumed between 0–3 Rs (Saturnian radii) along the field line of 75 degree North and the initial wave normal angle are assumed to be field aligned. The computer program used is similar to that of Shawhan (1967). The ray paths are computed for different frequencies of the SKR in the range of 3 kHZ–1 MHz.The result shows that the lowest frequencies are refracted more than the higher frequencies from the torus and effect diminishes with increasing frequencies. This explains the existence of the shadow zone near the equator as seen in the observations of SKR. Further, the results also explain the sp...