Page 6 - squires2012

78 & Contributions in Science, Number 520 Squires: Pico Formation Paleontology

road east of Gavin Canyon, 701 m (2300 ft.) north and 267 m
17934 (875 ft.) east of southwest corner of section 10, T 3 N, R 16 W.
Collectors: G.M. Dorwat, March 22, 1943, and R.L. Squires,
October 21, 2011. 17919. 118u329380W, 34u21916.50N. Eleva-
9659 tion 506 m (1660 ft.), on ridgeline just below ‘‘0’’ in ‘‘10,’’ 480 m
(1575 ft.) north and 777 m (2550 ft.) east of southwest corner of
section 10, T 3 N, R 16 W. Collector: R.L. Squires, November 7,
17933 2010, and October 21, 2011. 17920. 118u329300W, 34u219120N.
Elevation 518 m (1700 ft.), on ridgeline 259 m (850 ft.) north
and 419 m (1375 ft.) west of southeast corner of section 10, T 3
17924 N, R 16 W. Collector: R.L. Squires, December 10, 2011. 17921.
118u329220W, 34u219,100N. Elevation 549 m (1800 ft.), on
ridgeline 152 m (500 ft.) north and 129 m (425 ft.) west of
southeast corner of section 10, T 3 N, R 16 W. Collector: R.L.
17923 Squires, December 10, 2011. 17922. 118u329140W, 34u219000N.
Elevation 479 m (1570 ft.), on east side of power line road just
east of trailer park, 198 m (650 ft.) south and 122 m (400 ft.) east
17925 of northwest corner of section 14. Collector: R.L. Squires,
October 9, 2011. 17923. 118u319400W, 34u20935.50N. Elevation
610 m (2000 ft.), 739 m (2425 ft.) north and 533 m (1750 ft.)
17922 specimens). west of southeast corner of section 14. Collector: R.L. Squires,
September 4, 2011. Equivalent to southernmost loc. of Dibblee
locs. (#2 (1992a). 17924. 118u319380W, 34u209530N. Elevation 632 m
(2075 ft.), on north–south-trending ridgeline, 1204 m (3950 ft.)
LACMIP 7752 R R R rare north and 488 m (1600 ft.) west of southeast corner of section
14. Collector: R.L. Squires, September 25, 2011. Equivalent to
17921 F 5 R loc. 213 of Grant and Gale (1931:102) and to the northernmost
loc. of both Rynearson (1938) and Dibblee (1992a). 17933.
118u319160W, 34u209350N. Elevation 582 m (1910 ft.), small
17920 specimens); outcrop north side of road along ridgeline, 671 m (2200 ft.) north
and 183 m (600 ft.) east of southwest corner of section 13.
Collector: R.L. Squires, September 4, 2011. 17934 [= approx-
(3–4 imately 422, 4720, and 7797]. 118u309220W, 34u209150N.
Elevation 552 m (1810 ft.), on east side of power line road just
7757 few north of small concrete building, 30 m (100 ft.) north and 975 m
5 (3200 ft.) east of southwest corner of section 13. Collectors: G.P.
Kanakoff (date unknown), G.A. Rynearson (1938), and R.L.
17919 F Squires, September 4, 2011. In vicinity of locs. 211 and 214 of
Grant and Gale (1931:102) and loc. F76 of Winterer and
17918 R R specimens); Durham (1962).
(5–9 STRATIGRAPHY AND DEPOSITIONAL ENVIRONMENTS
17917 R common In the eastern and central parts of the study area (Figs. 2, 3), the
Saugus Formation consists of fluvial (braided-river) deposits that
17916 5 C include siltstone, sandstone, conglomeratic sandstone, and
interspersed lenses of conglomerate. No mudstone was found,
nor were any fossils. The siltstone is green, red, or brown and
crops out mainly in the eastern part of the study area. West of
specimens); California State Highway 14, the green siltstones are intercalated
within lighter colored and coarser deposits. The sandstone is
urchins) (.10 medium to coarse grained and white on fresh surfaces.
Horizontal laminated bedding and low-angle crossbedding are
(sea common. Locally, there can be higher angle, large-scale trough
crossbedding. The conglomerate occurs as channel fills with
erosive bases and sharp tops. Crude fining-upward sequences are
Taxa Echinoidea tooth) (conifers) abundant paired. common, and crude imbrication of clasts is less common. Clasts
are matrix supported and poorly to moderately well sorted. Most
Continued. Decapoda (partial) (spine) sp. Vertebrata:Chrondrichthyes (ray sp. Pinophyta 5 A valves all of the pebble- to boulder-size (up to 50 cm length) clasts are
commonly rounded to subrounded, but some are flat. They
mostly consist of leucogranite and granite, which together make
1 Arthropoda: leg Echinodermata: Eucidaris Myliobatis cone Abbreviations: or up approximately one-half of all the clasts, with the granite
commonly accounting for 30% and leucogranite 20%. Other
Table Crab Plantae: Pine Some * clasts, listed in decreasing abundance are gneiss, volcanic
porphyry, quartzite, anorthosite, hornblende-rich diorite, schist,