To Oil and Gas E&P Professionals:
A major reason for dry holes or uneconomic discovery wells in the E&P industry is tight reservoir rock. Dispersion occurs naturally in seismic data and is caused by fluid movement relative to the rock matrix when excited by the seismic wave. Apex Spectral has invented, patented and commercialized a robust and reliable method to measure this dispersion. The measurement called ADF® (Alpha Dominant Frequency) is largely proportional to three factors: reservoir fluid viscosity, intrinsic permeability, and thickness - all of which are critical factors in finding commercial hydrocarbons.
Henceforward, drilling dry holes due to tight reservoir rock can easily be avoided by the inexpensive application of ADF®. Another benefit of ADF® is that it acts as a DHI, because typical hydrocarbons like Brent, WTI or Saudi Light have much lower viscosity than brine causing much stronger dispersion in seismic data.
New or legacy seismic data is the only input required to compute an ADF® DHI SEGY cube identifying anomalously dispersive zones. This cube then indicates porosity and permeability sweet spots, and due to their low viscosity - hydrocarbons.
Broadband seismic data has been observed to give outstanding ADF® measurements for reasons that include better low frequency. At the same time, good compelling results are routinely achieved from older vintages of seismic data. Well data is not required or used to set ADF® run parameters, but can be helpful both as a check on the overall process and to help interpret results.
As a reservoir is produced, the viscosity of the typically mixed reservoir fluids (i.e. oil, gas and brine) drops rather quickly as the water saturation increases. This materially reduces dispersion, thereby causing a large 4D effect on ADF®. The absence of ADF® anomalies at known pay zones makes ADF® a highly effective tool to track and measure depletion effects, and numerous results show ADF® is superior to amplitude for tracking reserves and identifying near field step out locations.
ADF® DHI technology is being applied in basins worldwide covering a broad range of geologic settings and rock types (e.g. sandstones, carbonates and fractured reservoirs) to materially reduce risk and increase flow rates. By working together we can avoid dry holes caused by tight reservoir rock, and identify likely hydrocarbon charged prospects by imaging areas of high dispersion. Apex offers ADF® DHI services on a commercial basis, if you have interest in Apexs technology and services, please contact us.
Subsalt Gulf of Suez ADF® Results
ADF® DHI Overview