Hidden Treasure Fossils of the San Francisco Area Network Parks

Hidden Treasure
Fossils of the
San Francisco Area
Network Parks
• Fossils are used to date rocks and
determine the environments in which they
formed.
Park resources are important for
understanding the local Franciscan and
younger rocks, particularly of Paleocene
age.
• This study determined baseline
information on fossils known from parks,
their significance and potential for future
discoveries.
Information used to address future
management of the resources. Areas of
potential poaching, where to be concerned
for destruction of fossil resources by
disturbances.
• Literature, database and interview-base
study
Next steps could include field research in
areas of potential significance or threats.
Determining where fossil materials from
parks resides in museum collections.
John Muir
Eugene O’Neil
Pinnacles
SF
Franciscan Rocks
Melange, North Baker Beach
Graywacke Sandstone
Submarine landslide
Ribbon Chert
Deep sea mud
Pillow Basalt
Submarine volcanic flow
Chert & Radiolaria
200
–
100
Million
Years
Old
200 – 100 Million Years Old
Graywacke & Mollusks
130 – 100 Million Years Old
Plate Tectonics and Franciscan Rocks
Ft. Funston
Mori
Point
San Pedro
Point
Beach
Dune
Bay
Soil & Stream
Geologic Cross Section
A
B
Colma Formation, Baker Beach
Marin Headlands Terrane Jurassic-Cretaceous (~200 – 95 mya)
Zooplankton (radiolaria), mollusks (ammonite, belemnite, bivalve)
Alcatraz Island Cretaceous (130 mya)
Bivalve mollusks
Mori Point Cretaceous (125 -100 mya)
Zooplankton (radiolaria, foraminifera)
Near Devil’s Slide Paleocene (~63-56 mya)
Zooplankton (foraminifera), mollusk (gastropod, bivalve),
crustacean, echinoid
Fort Funston Pliocene-Pleistocene (3 mya – 11,477 yrs )
Mollusks (gastropod, bivalve), sand dollar, crustacean, marine worm
(polychaete), woolly mammoth, giant ground sloth, mastodon, horse,
camel, canid and split-toed ungulate
Phleger Estate Pliocene-Pleistocene (~5 mya – 11,477 yrs )
Mollusk (freshwater gastropod, bivalve), unnamed vertebrates,
plants, woody debris
Coastal Areas Pleistocene (1.8 mya - 11,477 yrs)
Microscopic algae (diatom), pollen, mammoth, bison, ground sloth
EUON
JOMU
JOMU
PORE
PORE
Far western part of the peninsula Eocene (55.8 - 33.9 mya)
Zooplankton (foraminifera), plants, seeds
Point Reyes Beach Miocene (23 - 5.3 mya)
Mollusk (bivalve), sea star-like animals (echinoid)
Duxbury Point to Abalone Point Miocene (~10 - 5.3 mya)
Microscopic algae (diatom), zooplankton (foraminifera), sea star-like
animals (echinoid), crustacean, whale bone and skull
Drakes Beach Miocene-Pliocene (~10 - 4 mya)
Microscopic algae (diatom), mollusk (gastropod, bivalve), sea starlike animals (echinoid), crustacean (isopod, crab, shrimp), otarioid
seal, walrus, balaenopterid whale, dugongid sea cow, fish and
mammal bones
The sea cliffs at Bolinas Pliocene-Pleistocene (~4 mya – 250,000 yrs)
Microscopic algae (diatom), zooplankton (radiolaria, foraminifera),
sponge, crustacean, sea star-like animals (echinoid), mollusk
(gastropod, bivalve), whale skull, sea lion, porpoise, bony fish,
sharks, feathers, plant, carbonized wood
Tomales Bay and Olema Creek Pleistocene (~1.8 mya - 11,477 yrs)
Microscopic algae (freshwater diatom), mollusks (bivalve, gastropod,
scaphopod), arthropod, plants
PINN
Conclusions
Diverse fossil resources are present in SF network parks.
•
Given the potential for unauthorized collection, a field-based
inventory of paleontological resources is recommended.
•
The field work could be accomplished by cooperative agreements
with museums and universities.
•
Interviews with the specialists who have worked in the parks could
provide more background information.
•
Specimens retrieved from parks and stored in other repositories
should be located.
•
Scientifically significant material threatened in the field should be
stabilized or retrieved and curated.
•
Park staff should be made aware of the potential for discovery of
fossil material during other field work.