Field Notebook: Texas 1957a
Page 272
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PG. 156 6) Covered, 7' probably mostly light brown shales and siltstones. 7) Calcarenite, medium gray to orange-brown. A few small pebbles near base, grades into fine sand near top. Upper 1" to 2" siliceous ferric rich. 8) Covered, 25', this seems to be light brown shale for most part, some siltstones and some very fine sandstones. 9) Limestone, organic frag.; some black chert (Ord?) Crinoid columns, bryozoans and fusulines. 1' to 1.5'. 8/2/57/2. 10) Shale, siltstone and very fine sandstones; light brown weathering. 17'. 11) Covered, 27'. 12) Massive limestone, light gray to light tan weathering. Lower 6'-10' have large limestone cobbles, small amount of fine chert pebbles. Collection 8/2/57/3. 58'. This unit has been dolomitized top of NE most knoll. PG. 157 Section 22 - NE of Sullivan Ranch Road. Starts between 2 windmills. Gaptank below is badly folded and faulted, chert conglomerate, breccia in the greenish chert, beds of chert below seem well bedded and not excessively broken - Gaptank limestone is present as well as brown sandstones. 1) Conglomerate, much chert pebbles and limestone cobbles. Brown cement or matrix dip is about 15° due N. 20'. Becomes fine upwards, some organic fragmental material comes in. 2'-3' beds. 8/2/57/4. 2) Limestone, medium gray, mostly organic frags., some small chert pebbles. Crinoid stems dominant. Has brownish hue (weathered), Collection 8/2/57/5 about 20' up from base. Collection 8/2/57/6 about 60' up from base - thickness - 78'+ the upper beds dip south about 46 to 60°, I suspect this unit is faulted Leonard, a thin bit of upper Hess is #1 and no lower Hess or Wolfcamp at all. Leonard or Upper Hess resting on Dimple, Haymond Tenus and Cabaous. PG. 158 In walking over this outcrop as far as the Decie fence line there seems to be no exposure of Pm rocks older than these in section 22. The green-brown silty sands (Haymond?) is in a very tight syncline or overturned anticline which strikes near E-W paralleled with the fault in the Leonard. I believe the displaced rocks are faulted down because I can trace this structure about a quarter of a mile. The Cabonferious breccia zone is quite thick here (40-50') and has an upper surface which appears wave cut. It dips steeply to the N (as much as 55°). This surface has since been distorted and is now cut by many secondary faults. The complete field relationships of these beds are unfortunately concealed. Collection 8/2/57/7 - Blue shale 20' interval below Hess limestone ledge, N45°W of Decie well now windmill. PG. 159 Collection 8/2/57/8 - Biohermal or Biostromal zone in base of Wolfcamp Conglomerate (G.A. Cooper locality) almost due west of Decie well-windmill.