The Amoco Blackburn #4, Shell Eagle Springs #1 3250-3500', Gulf Gose EU Fed. #1, and the Willard Pease #1 samples were reset by a thermal event greater than the closure temperature of about 110 degrees C during the Late Eocene or Early Oligocene, approximately 34.6-47.5 Ma. The Suntide 1-A probably reflects a similar if not geologically identical thermal history. The absolute temperature and duration of this thermal event are poorly constrained. A 150 degree C event with a duration of about 2 million years could have reset the radiometric clock. Conversely, a 120 degree C event which lasted about 5 million years, or a 200 degree C event with a duration of approximately 150,000 years may have occurred.

The Wexpro #2 Jiggs 5000-5300' sample appears to have experienced a similar thermal event during the Miocene, about 15.2 Ma. This is the youngest generation event observable in these samples, and probably reflects the final emplacement and cooling of the adjacent Ruby Range metamorphic core complex.

The Marlin 1-4 well in Butte Valley apparently did not see the effects of 34.6-47.5 Ma or 15.2 Ma Tertiary thermal disturbances. It last saw a thermal event greater than the closure temperature approximately 237.1 Ma in the Triassic.

The surface outcrop microcline samples from the Valmy and Chainman Formations appear to contain microclines which are similar to the subsurface Tertiary and Chainman samples. The surface samples have experienced a very different thermal history. The subsurface samples were thermally heated during Tertiary events about 34.6-47.5 Ma or 15.2 Ma while the surface samples show much older ages and no evidence of Tertiary thermal events. The youngest observable thermal event in the surface samples is Jurassic, about 150.8 Ma.

The oil fields in Railroad and Pine Valleys have seen a similar Eocene thermal event capable of generating hydrocarbons between 38.9 and 51.5 Ma. The last time of oil generation in these areas is Eocene. The demonstration of similar age events in the Gulf well in White River Valley and the Willard Pease well south of Newark Valley suggests that these areas may have seen the necessary thermal event capable of hydrocarbon generation.

The absence of similar age thermal events in the surface samples suggests that Tertiary basin development and burial are necessary to generate thermal conditions capable of creating these types of hydrocarbon accumulations. The absence of Tertiary thermal events in Butte Valley suggests it has a very low potential for Tertiary-age hydrocarbon accumulations.