Print this pageIntegration of Seismic and Iodine Surface Geochemistry to Finding Mississippian Reservoirs, Williston Basin
TEDESCO, Steven A.
The use of iodine surface geochemical 
surveys
is becoming more prevalent in
defining areas to focus seismic surveys that target Mission Canyon and Lodgepole
(Mississippian Age) reservoirs in the Williston Basin. The iodine surveys
initially are the reconnaissance type, whose purpose is to identify general
areas of microseepage. This type of survey usually utilizes the existing road
net to define the grid. This survey is usually followed by either a semi-detail
or a very detail survey. The grid spacing for a detail survey is usually at
1/10th to 2/10ths of a mile, to specifically define the area of leakage. In
conjunction with the detail iodine surveys, existing 2-D data is reviewed,
acquired or reprocessed to identify the probable target and outline a general
area for leasing. Evaluation of the surface geochemical data is critical in
defining the target area in terms of seismic acquisition, drilling and leasing.
Failure to systematically evaluate, identify the appropriate grid density and
size, adequate number of samples and field and laboratory protocols to define
the target can cause misdirection and misinterpretation of a survey. In
addition, the use of statistics, pattern recognition methods, previously drilled
surveys and models can significantly impact the success of interpreting the
surface geochemical data in an undrilled area. Statistically, surface
geochemical and seismic surveys integrated together have a greater success rate
than the sole use of seismic surveys
for exploration by a difference of 5 to 1.
Examples of utilizing this approach, and the results of drilling will be
presented that specifically target Mississippian reservoirs in the Williston
Basin.