Abstract: Paleogene-Neogene Macrofossils of the Canada Posa Region, Santa Cruz Island

SHAPIRO, Russell S. Department of Geological Sciences, University of California (Santa Barbara), CA 93106

The Canada Posa region, southwest Santa Cruz Island, contains a rich Tertiary marine fossil record. Previous studies have focused on the micropaleontology for biostratigraphic correlation with the mainland formational equivalents. However, the macrofossil assemblages are potentially more useful to the field geologist for island biostratigraphy. In addition several fossils are useful for establishing correlations with mainland deposits, such as the Paleocene gastropod Turritella pachecoensis.

In order to create an inventory of the macrofossil record, collections were made during 1996 and 1997 in the vicinity of the Christy Anticline. Additional specimens were culled from the U.C.S.B. Paleontological Collections. The following is a list of newly recognized specimens, by formation, identified by as of November, 1997.

1. POZO FM.: Ampullina sp.; ?Cardium; ?Chione temblorensis; Crassatellacollina; Dosinia (Dosinidia) cf. D. margaritana; indet. gryphaeid; indet. oyster; unidentified large "sabellariid" tubes; unidentified small "sabellariid" tubes; cf. Solen; ?Trichotropis; Turritella ocoyana.

2. CANADA FM.: Anadara sp.; Balanophyllia cf. B. variabilis; ?Cardium; cidarid (cf. Eucidaris) spines; Dendrophyllia aff. D. variabilis; Dosinia (Dosinidia) cf. D. margaritana; Eutrephoceras sp.; Ficus sp.; Glycymeris; indet. gryphaeid; Ostrea cf. Q. idriaensi; indet. oyster; Polinices spp.; ray dental battery; unidentified large "sabellariid" tubes; unidentified small "sabellariid" tubes; Spiroglyphus sp.; "Trophon" sp.; Turritella ocoyana; Turritella uvasana; Venericardia sp.; fossilized wood casts.

3. COZY DELL FM.: ?Cercidiphyllum.

4. RINCON SHALE: Ctenoid fish scales.

5. SAN ONOFRE BRECCIA: Ostrea cf. O. vespertina; Ostrea eldridgei; Pecten (Lyropecten) miguelensis.

AAPG Search and Discovery Article #90935©1998 AAPG Pacific Section Meeting, Ventura, California