new drill results out, page-28

robertb, I doubt TXN's IPs would be one-hour tests. Possible, but very unlikely. My guess is that these are the standard 24-hour IPs.

One reason is that the flow needs to be (mostly) cleared of frac fluids, which takes several days (sometimes weeks). "24-hour IP" is not the first 24 hours of production due to the poor testing until frac fluids have cleared. Hydrocarbon output usually increases as frac fluids decline. Another oiler I watch (no longer hold) sometimes gives initial output results but also says 24-hour peak IP rate will be reported when the well stabilises (i.e. frac fluids are mostly gone). Past TXN announcements have said the flow rates would been calculated after most frac fluid has been recovered, so it doesn't make sense that they would test hydrocarbon output for just one hour.

A second reason is that TXN's stated IP to 30-day flow decline rate is very similar across wells. If IP was tested for only one hour, it would have high error variance and therefore much more variation with 30-day rates.

Third, I suspect there are industry standards or possibly requirements for official IP flow statistics. Remember that these stats are used by potential acquirers and likely considered by independent reserves evaluators (Netherland Sewell etc). It is unlikely one hour testing would meet that standard.

The decline from IP to 30-day output would not indicate a one-hour initial IP. Instead, the decline occurs partly because the well's choke is reduced (smaller) during this time to maintain high pressure for longer, thus reducing output. There is also considerable natural decline in horizontals -- up to 80% decline in the first year, then flattens for 20 years or more.