In the Appalachian Basin gas wells are air-drilled and amulti-zone well stimulation are the normal completions.The majority of these wells are logged with air in the holeafter removing the fines from drilling using compressedair. The sandstones in the Devonian series of theAppalachian Basin are listed in Table 1. These areassociated with thinly bedded laminated sand shalesequences causing the Resistivity log to be lower. Manyproducing gas zones may be defined as so-called lowresistivity pays.Normal logging programs do not respond properly tothin or very thin pay zones which will be averaged withsurrounding shales. This log response can cause payzones to be overlooked as stimulation candidates.Information can be found from openhole logs in air filledholes, using a different methodology, to more accuratelydetermine producing gas zones.Appalachian Basin gas zones of the Upper Devoniansection will be analyzed. A strategy will berecommended to help determine which zone(s) containproducible gas reserves or may not be worthy ofhydraulic fracturing treatments. These decisions couldhave significant economic implications for operators.Appalachian Basin log examples, stimulation design andproduction response will be included as part of thisinvestigation.
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