Field Notebook: Texas 1957b
Page 93
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Transcription
8/26/58/5 - Ammonid zone Dugout Mts. Sect. 26, bed 4. The Hess limestone conglomerate - grade laterally into yellow-orange siltstones and shale. The siltstone and shale increase to the SW along the face of Dugout Mt. at the expense of the upper limestone and conglomerate of the Hess ledge. All of the limestone are lenticular in the lower Leonard. Same thickness for 0">2' or 3' along strike, one of the highest conglomerates disappears 20' +- to 0 in 100 yards. PG. 145 The Hess ledge thins from Sec. 26 to the NE looses conglomerate and limestone and picks up siltstone and shale and then back again to conglomerate. Big facies picture - no really good top to the "Wolfcamp" sequence here. Wilde showed me the conglomeratic ammonite bed on Dugout. It is full of the big undescribed Pseudoschwagerina and other fauna of about same horizon. Equivalent to Hess Ranch section. PG. 146 8/27/58 SW of Fault at Sullivan Ranch Road. 8/27/58/1 - Hess ledge - upper part about equivalent to bed 25 of section 20. 8/27/58/2 - float about 20' up in interval between first Leonard limestone and Hess ledge. 8/27/58/3 - about 20' above location of #2 above. NE of fault - Sect. 21. 8/27/58/4 - Hess ledge at bottom of Hill - has Pseudoschwagerina (small) and is at top of Hess interval - bed 1. 8/27/58/5 - cobble of Hess ledge bed 1. 8/27/58/6 - top of first Leonard limestone bed 12. PG. 147 Skinner and Wilde talked about a Gilliland Anticline which connects with Hovey and Davis Mt. - They draw the axis down along Blue Mt. and across Jail Canyon into Iron Mt. and then out into the Marathon Basin. Skinner believes the lower portion of the Leonardian doesn't make it across this Anticline to the west of about Iron Mt. There the Hess ledge is mid Leonardian according to him. Questions to consider - 1) What happens to the S. Crassictoria zone to the west - note one boulder collection from Dugout Mt. which may have it. Wilde suggests the Wolfcamp shale will probably be absent on the West Pyle Ranch Area - [With friends like these, who needs...]. PG. 148 8/28/58 NW Slope Leonard Mt. {note: illustration: W E bed 1: Covered.