Field Notebook: Texas 1957a
Page 226
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Transcription
The absence of "Conglomerate" bed in the lower Hess in Section 8 and in Section 11 leads me to believe the conglomerate in the Wolfcamp Hills and in section 10 are local lenses and not a good mapping horizon. The light gray limestone at the approximate level of these conglomerates appear to be a fairly consistent outcropping horizon. Without the benefit of fusuline evidence I would at this time suggest the beginning of silty and fine to very fine sandy bed above the highest "cyclic" Wolfcamp in the Wolfcamp Hills seems to be a persistent unit also, although it is often obscured by talus. PG. 85 The upper beds of the Wolfcamp are apparently missing in the western portion of the Brooks Ranch as a result of erosion. The limestone cliff forming Wolfcamp units is probably equivalent to the #2 gray limestone member of King in the Hills proper. Upper Wolfcamp Cyclic deposits were observed on the Brooks Ranch (to be measured later) and also at section 11. The Gaptank limestone becomes the prominent cliff (no it doesn't) former in the low - builds east of section 11 because of thinning of the #2 gray member of King and also because of some thickening of that (gaptank) unit to the east. {note: this paragraph was crossed out} The upper Wolfcamp beds in Sect 11 are in a structural low and show evidence of being deformed slightly prior to Hess limestone deposition. PG. 86 7/11/57 Section 28 Covered below Section 12; at head of draw northwest of section 10. 1) Limestone, gray, massive beds, 3 to 20' bedding biohermal, rather fine fragments - 51'. 2) Covered 7'. 3) Limestone, gray, uneven bedding near base, more massive higher. Gray weathering. Crinoid stems and fusulines near base. 3'. 7/11/57/1. 4) 1' covered. 5) Calcarenite, yellow-brown weathering, brown-gray on fresh surface. Some fusulines and brach shell fragments - 1.5', 7/11/57/2. 6) Covered 2'. 7) Calcarenite, yellow-brown weathering some mottled grays, coral and crinoid and brachiopod fragments. [1'] 8) Covered, gray-brown shale probably, 1.5'. PG. 87 {note: illustration: Section 12: bed 3: 7/11/57/1 bed 4: 7/11/57/2 {notes beds4-7: 5.5' total}