The Holbrook news., 1919-04-11

naturally led to a further investi-
 gation of this sector of the field
 in regard to it's geological fea-
 lures and also for favorable
 structural conditions and any
 possible evidence of oil.
 The formation was found to
 have mean dip north of about
 one-half degree. gradually rising
 toward the south in a series of
 gentle terraces, locally varied by
 folding, until some twenty miles
 south of Holbrook a pronounced
 anticlinal fold was observed
 which was traced by the writer
 in a southeasterly and north
 westerly direction for a distance
 of something more than forty
 miles. This is the Great Anti cline. Just south of Holbrook and extending in an easterly and
 westerly direction is another fold. not so pronounced and hav- ing a number of local variations which form domes as we'll as an anticlinal structure with it's com elementary syncline.
 Numerous rock tests proved conclusivelY that oil does exist in this field. Further evidence is found in some wells which have been drilled for water, notably one about two miles southwest of Holbrook, which entered the beds of the upper PennsyIYanion series, and in two others about six miles northwest of HoIbrook, one of which is about 400 feet deep. Nodules of oil appear in the water pumped from these wells. The first has penetrated the upper Pennsyl- Yanian beds ta a depth of only 190 feet and the 400 feet well has but just entered the same formation, so far as has been ascertalnable. But these beds are known not to be oil bearing as has been demonstrated in the  San Juan Field of Southwestern Utah. north of Holbrook, where oil has been produced from shallow depths but in beds of the lower Pennsylvanian. series. These latter are nowhere ex- posed in the Holbrook Field and should be reached at a depth of not less than 800 feet to 500 feet below the surface of the upper Pennsylvania, or the surface of the ground where the latter is exposed, and will be found to be not less than 1000 feet thick. This is the first oil horizon, and it is probable that not any other than wells having a moderate l production will be developed in these beds. Depth must be at- tained and a probable depth be- low the surface of 25O0 feet or more should be the objective of any operators intending to get oil.
 Three companies now are in operation. but weather condi- tions have greatly retarded work. No material depth has yet been attained, the beds of the upper PennsylYanian not having been passed through. The HoIbrook Oil Company now has a rig in process of erection on one of their tracts contiguous to the Great Anticline and pro- pose to push operations as rapid ly as weather conditions will permit. They also intend drill ing on another of their tracts on the small anticlinal structure near Holbrook. Several other enterprises are in process of for nation and the writer is inform ed that both the Carter Oil Com pany and the Ohio Oil Company are preparing to explore several different-sections of the field.
 Several prominent geologists have examined the field during | the past year and all are unani- nous in a favorable opinion re- garding the possibilities of the Holbrook Field for the produc- ton of oil. Once the question has been determined, the area of the field is so extensive that it is certain to become a prominent factor in the oil industry of the o0upfrv