Vertical seismic profiling experiments have been completed simultaneously in two approximately 400m deep wells. The field experiment provided the data necessary to examine and compare the virtual source method VSM and zero-offset vertical seismic profiling ZVSP. Both methods provide an improved understanding of the acoustic heterogeneity of the weakly consolidated sandstone aquifers in the Perth Basin, WesternAustralia.Acquisition parameters for the simultaneous VSP experiment were designed to optimize the chance of removing unnecessary wave modes. The number of hydrophones deployed is of considerable important if a detailed velocity distribution between the two vertical wells is to be achieved. Low ray coverage cells tend to have incorrect velocity values. We examine potentially serious statics problems that can result from using a 1400 kg weight dropped source in dry unconsolidated sand. We provide an example of how these problems can be successfully managed by measuring simultaneously in two wells. We comparing the velocities distributions obtained from VSM and ZVSP methods with sonic and gamma wire-line logs. Both methods are demonstrated to be effective for obtaining detailed velocity distributions. In particular the virtual source method is highly promising for imaging velocity distribution between two vertical wells where ray coverage is high.
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