Due to the ill-posed nature of nonlinear inverse problems of borehole geophysics, a parameterization approach is necessary when the available measurement data are limited and measurements are only carried out from sparse transmitter-receiver positions (limited data diversity). A potential remedy is the joint inversion of multiphysics measurements. A parametric inversion approach has desirable a...

[1] The primary goal of the Ocean Seismic Network Pilot Experiment (OSNPE) was to learn how to make high quality broadband seismic measurements on the ocean bottom in preparation for a permanent ocean seismic network. The experiment also had implications for the development of a capability for temporary (e.g., 1 year duration) seismic experiments on the ocean floor. Equipment for installing, op...

A multidisciplinary study involving hydrogeochemical sampling and borehole geophysics was undertaken to study the nature and occurrence of saline groundwater on two islands in British Columbia, Canada. Saturna and Hornby Islands are located at the south and north ends, respectively, of the Canadian Gulf Islands situated off the lower mainland of British Columbia. Two large-scale geochemical sam...

SUMMARY Use and interpretation of wireline lookahead VSP combined with LWD seismic while drilling and LWD sonic log for base of salt prediction, a case study offshore Brasil deep offshore Campos. It aimed to assist drilling decisions by obtaining a more accurate prediction of Base of Salt depth. Setting the 9-5/8" casing point was key from a drilling perspective.

More percentage of new productions in oil industry is from unconventional oil and gas such as oil shale, tar sand, laminated sand, tight oil (siltstone), tight gas, gas hydrate, and igneous rock, because the conventional oil and gas can no longer meet the need of the world. Researchers in response pay more attentions to the unconventional resources. Formation properties such as total organic ca...

Seismic interferometry has become a technology of growing interest for imaging borehole seismic data. We demonstrate that interferometry of internal multiples can be used to image targets above a borehole receiver array. By internal multiples, we refer to all types of waves that scatter multiple times inside the model. These include, for instance, interbed, intrasalt, and water-bottom multiples...

The usage of Distributed Acoustic Sensing (DAS) in geophysics is rapidly gaining popularity due to its dense spatial sampling and low operation cost if the optical fiber is easily accessible. In the borehole environment, optical fibers for DAS are often readily available as a part of other sensing tools, such as for temperature and pressure. Although DAS provides single axial strain measurement...

The characterization of fluid-transport properties of rocks is one of the most important, yet difficult, challenges of reservoir geophysics, but is essential for optimal development of hydrocarbon and geothermal reservoirs. Production of shale oil, shale gas, heavy oil and geothermal energy, as well as carbon-dioxide sequestration, are relatively recent developments where borehole fluid injecti...

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