DHIs: Fluid Contacts Hydrocarbons are lighter than water and tend to form flat events at the gas/oil contact and the oil/water contact. Thicker Reservoir Fluid contact event Slide 20 Here are two more seismic models (with added noise) to illustrate a fluid contact reflection Note the “hockey stick” in the upper image For the lower image, the reservoir is thinner we only see the fluid contact, not the handle portion of the “hockey stick” IMPORTANT – a fluid contact will be flat (horizontal) in depth, unless there is a hydrodynamic gradient causing it to tilt Since we are looking at data in the time domain, there can be some distortions if the velocities above the reservoir vary laterally and cause a flat event in time to be tilted on a time section Thinner Reservoir Fluid contact event Courtesy of ExxonMobil L12 – Data Analysis