Depths, Times and Velocities - Facts or Opinions?
Peter Wang, Technical Sales Advisor; Gustavo Morales, Sr. Geophysicist - Technical Sales Advisor
Featured Technologies: Explorer™
Wells are drilled in depth; that’s a fact. Seismic data is collected as a function of two-way time; that’s also a fact. Velocity describes how time and depth relate to each other, and while well-based velocity measurements represent a certain group of facts, how to arrive at velocities appropriate to converting seismic time to depth is definitely a matter of opinion.
If we search for an easy way to come to an informed opinion about velocities, we will likely come away frustrated. The truth of the matter is, your best path forward will be governed by where you start in terms of data availability, the difficulty of the technical question to be resolved (which is a function of geology), and project budget and timeline constraints. Simple, hard-wired approaches will work in some cases, but if they don’t, the E&P enterprise will end up exposed to one of the most severe and costly risks possible - landing the well in the wrong location.
Post-appraisal of an unsuccessful well is never easy, but two answers that you don’t want to have to give to rationalize incorrect depths are:
- We could not make use of all of the information available.
- Our technology wasn’t flexible enough to implement the best method for domain conversion in this particular situation.
In this presentation, we will show how an integrated set of velocity and database tools can function together to enable velocity workflows ranging from simple to complex, that use many different kinds of velocity information (vertical functions, cubes, markers, checkshots, constants, crossplot relationships, analytical functions, stacking velocities), and how the resulting models can be deployed for different missions – depth conversion, depth imaging, seismic inversion, and pore pressure prediction.
Peter Wang is a Technical Sales Advisor with Paradigm. He has an MS in Geophysics and an MBA from the University of Houston, and is a Texas Licensed Professional Geoscientist (“PG”). He has a thirty-year history in the geophysical industry, having worked for Schlumberger, Amoco Production Company, and Kelman Seismic Processing.
Gustavo Morales is a Geophysical Engineer and Technical Sales Advisor at Paradigm. With over 13 years’ experience, and successful career in the whole geophysics spectrum (acquisition, processing and interpretation) he was able to get involved in several integrated and multidisciplinary projects which include different basins and/or tectonic settings in more than 15 countries of 7 continents, special approach for complex reservoir conditions including: tight reservoirs, heterogeneous sequences highly faulted/fractured areas and severe unconformity settings.