Rock Physics SIG: Dependence of shale velocity on clay-mineral content and temperature* - Sep 5th
Sponsored by NER, CGG and Ikon Science
Event Location:
CGG
10300 Town Park Dr.
Houston, TX 77072
NOTE: You Must be Logged In to Register.
Speaker: Keith Katahara
Well-log sonic velocities in shales from several basins are independent of clay-mineral content at low temperatures. As temperature increases, shale velocities start to decrease with increasing clay. The clay-velocity slope becomes increasingly more negative as temperature increases.
The strong variation of velocity with clay content at high temperature is not due to varying porosity as indicated by the dependence of density on clay content. The pattern of clay-velocity variation is consistent with increasing clay-mineral orientation with increasing clay diagenesis.
One practical implication is that pore-pressure estimates based on shale velocity may need to consider clay effects if clay content varies significantly from layer to layer. Given that clay content is often poorly known, I suggest using the shale velocity at the threshold between grain-support and clay-mineral-support for pressure analysis.
NOTE: You Must be Logged in to Register
5:15pm Refreshments
5:30pm Presentation Begins
6:30pm Adjourn
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