What is Exploration Drilling?
There are many different types of drilling methods, but each one has its own sets of application procedures and advantages. The exploration drilling is part of the list of known drilling methods, and this is viewed as a highly crucial step that should take place before the development drilling.
Exploration drilling is of utmost importance in obtaining the actual measurements of temperature and rock samples. This method is also used in retrieving a sample of fluids for the purpose of chemical analysis. It is true that geophysical methods can provide useful and valuable information regarding the sub-surface which is proven essential especially when determining the best drilling locations, however, to be able to get the actual temperature as well as fluid measurement, samples must be obtained through exploratory drilling.
There are many techniques for exploratory drilling such as:
- Exploratory Wells
- Thermal gradient holes
- Core holes
- Slim holes
These methods are used simply because these are less expensive as compared to drilling full-sized production wells. On the other hand, exploration drilling can be costly, but this provides the most reliable and accurate pieces of information during the phase of exploration. In many instances, this is the final stage of exploration.
The Significant Role of Exploration Drilling in Geothermal Exploration
Exploration drilling is proven essential in terms of identifying is geothermal reservoir can produce enough hydrothermal fluids needed for reliable power generation. This drilling method is used to build accurate models of the reservoir based on the hard evidence that has been observed down the hole. More of exploration drilling’s significant role in geothermal exploration are estimating production potentials, defining reservoir boundaries, characterizing subsurface geology and providing important fluid geochemical data.
Exploration Drilling Field Procedures
The field procedures actually vary depending on the type of exploratory drilling performed. Drill rig for exploration drilling is much portable and smaller as compared to production well-drill rigs.
Best Practices for Exploration Drilling
For most drilling operators, competent and careful planning is a crucial step prior to starting the drilling process. Various factors need to be taken into accounts such as well parameters, cost, schedule, drilling equipment, geographical location and more.
Drilling closest source of water is usually ultimately beneficial, or else water for drilling mud needs to be transported into the site, and this can be costly. Accessibility of the site is also important and must be considered.
The larger truck that carries heavy equipment must have convenient, reasonable and reliable access into the site and there should be enough space at this site to accommodate the needed supplies and equipment. Drilling during the year’s calm times is significant as well. Remember that high precipitation, hot and cold weather extremes can affect the equipment, work conditions, and mud system. This can lead too slow progress of the drilling and much higher expenses.