The use of a complex wavelet transform with similar properties to the DT-CWT in seismic processing was suggested in Fernandes (2001). A wavelet basis was used for linear inversion with application to well logging in Li et. al., (1996), using a fully decimated wavelet transform and the Haar wavelet. However, the transform used does not have the shift invariance and directional selectivity proper...

The internal structure of a convergent plate boundary was the focus of ODP Leg 170 in 1996 at the subduction zone off Costa Rica. Although the structure of the subduction zone is rather well known from seismic surveys, prior to drilling of ODP Leg 170 it was a matter of discussion whether it is accretionary or non-accretionary. With a neural network approach, we confirm the evidence gained duri...

The objectives of coring and downhole logging at this site are tied to completing the transect of scientific drill sites across the Northern Cascadia Margin to further constrain models for the formation of marine gas hydrate in a subduction zone acretionary prism. The depth to the BSR rapidly becomes shallower around this site and is only half the depth (~125 mbsf) than at Site U1327 (~225) mbs...

Seismic velocities in rocks at ultrasonic frequencies depend not only on the degree of saturation but also on the distribution of the fluid phase at various scales within the pore space. Two scales of saturation heterogeneity are important: (1) saturation differences between thin compliant pores and larger stiffer pores, and (2) differences between saturated patches and undersaturated patches a...

Reservoir characterization plays a crucial role in modern reservoir management. It helps to make sound reservoir decisions and improves the asset value of the oil and gas companies. It maximizes integration of multi-disciplinary data and knowledge and improves the reliability of the reservoir predictions. The ultimate product is a reservoir model with realistic tolerance for imprecision and unc...

The seismoelectric logging method is based on measuring the electric field generated by seismic waves in a fluid-filled borehole. Two kinds of electromagnetic (EM) fields can be generated within the formation and at the interface of formations. One is a stationary or local EM wave and the other is a radiating EM wave. In this paper, we make various fractured borehole models with artificial mate...

A low power microprocessor controlled event-triggered seismic data logging system has been designed and implemented in the ocean bottom seismic capsule. Three channels of seismic data are digitized, formated, and stored under control of an Intersil IM6100 microprocessor chip. The processor also controls event triggering, acoustic diagnostics, battery voltage monitoring, and self-diagnostic func...

The electrokinetic effect in a fluid-saturated porous rock is defined as the coupling and conversion between seismic and electric energies. When seismic waves propagate through a fluid-saturated formation and cause a pore fluid-flow relative to the solid matrix, the motion of the cations in the fluidflow forms a streaming electrical current and induces an electromagnetic wave at any discontinuo...