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Transcription
Collection 8/16/57/11 - From 10' interval of limy beds below iron red Uddenites
sandstone horizon in 2nd Terrva block east of geologists' canyon.
The lower part of the cyclic beds are exposed to the east of geologists' canyon
above the #2 limestone member. There seems to be considerable structure (at
least for this area) as the #2 beds take a sudden dip beneath the cyclic beds.
The shale interval here is a light gray and is slightly silty.
4 to 5 of these cyclic calcareous sands are present. The bulk of the material is a
coarse rubble and includes dark gray limestone pebbles 2-3" diameter and has
mottled weathery appearance over all. I don't see how all of the structures here
can be attributed to draping over buried reefs although that is still within
possibility. The explanation of a SW-NE structure trend is appealing. These
beds seem to be faulted in the limestone units and flowage in the shales but no
definite such structures were observed.
PG. 39
8/17/57
(Section 36, Memior 88)
Section 29: Moore Ranch; 200 yards east of last Wolfcamp limestone exposure.
1) Covered, probably siltstones and shales, base of unit under alluvium.
2) Sandstone, light green-gray to brownish-gray to brownish-orange, very fine
grain quartz for most part; occasional conglomeratic beds. 4'.
3) Limestone, green-gray, fragmental hash, these are in a limy shale matrix and
are similar to the #3 bed, section 23. 27'.
4) Covered, 11'. (same as 3 in stream cut but considerable more clay %)
8/17/57/4.
5) Sandstone, weathers orange-brown; fresh is green-gray: very fine to fine
grain quartz; 1/5'.
6) Covered, 15'.
7) Calcarudite; light gray to light brown-gray weathering up to 6" cobbles, very
small amounts of chert. (8/17/57/1 - pebbles). 15' to top of ridge, this unit forms
dip slope here.
PG. 40
50 yards west of section 29; in a stream cut a 9' limestone underlies the
calcarudite. Thus it seems the calcarudite has been deposited in a eroded
surface of the limestone.
6)A. Limestone, light pink; massive weathered surface has a tinge of brownish-
orange. 0' to 9'. 8/17/57/3.
6)B. Limestone, light gray, some yellows; calcarenite 6" to 8" beds, Collection
8/17/57/2; 0' to 20'. These 2 units overlie 6) and underlie 7). {note: illustration
followed}
I think the Calcarudite is wave reworked material, not much transport, the cherts
yes, but most of the limestone have probably been reworked nearly in place.
Beds 6A and 6B weather into horizontal wavy "bedding" lines; these I have called
debris beds off reef highs and I suppose that would hold here too.