Tuesday, January 5, 2010

CAROL STADUM AND FOSSILS IN ORANGE COUNTY, SOUTHERN CALIFORNIA

I was introduced to WSM ten years ago and have been honored to attend their conferences and share research notes and adventures with WSM members. I am a Departmental Associate in the Invertebrate Paleontology section of the Natural History Museum of Los Angeles County and the Paleontology Division of the San Diego Natural History Museum. Both museums have talented paleontologists who have been very generous with their time and with whom I have completed several research projects.

I am presently finishing a study on Miocene (Relizian benthic foraminifera stage – late early to early middle Miocene) age calcarenite deposit in southeastern Orange County, locally call Pecten Reef. The limey matrix at Pecten Reef contains a large fauna of well-preserved mollusks similar to those now found off Central America along with calcareous algae and some magnificent echinoids.

When I was a child a neighbor took me to a hill east of the City of Orange that was littered with mollusk fossils from the Topanga Formation, primarily the gastropods Turritella ocoyana (Conrad) and T. temblorensis Wiedey. I knew then that the study of fossils was what I wanted to do with my life. I made a collection then, which is now in the San Diego Natural History Museum and I still used it 50 years later to compare fossils I collected then with species found in the Pecten Reef calcarenite. I find it a bit curious that the fossils I collected when I was 8 years old are the same species I find at Pecten Reef. I believe they contain the same fossil fauna because they are the same age, although the were deposited under different environmental conditions.

My work with fossils has included siliceous microfossils while I was at Scripps Institution of Oceanography, the University of Washington, and Lamont Doherty in New York. From micropaleontology I transferred my interests to malacology (the study of mollusks) during the 1960’s and 70’s, a time of rapid land development in southern Orange County. This was an amazing time with fossils were being exposed daily. Fortunately I was teaching by then and could rally students to help salvage specimens on weekends. During this time I was able to spend a summer collecting in the Lias limestones of Germany and was overwhelmed with the beauty, diversity, and abundance of ammonites there. Most of the collection I made were left in a museum in N├╝rnberg .

Since retiring I have worked as a consultant, primarily to the City of Laguna Hills, and have developed a nice museum of local fossils and a strong paleontology program for the City. This has included a video about local fossil recovery and a fossil website http://www.gotfossils.com/.

Whether I am in a lab or in the field, working with fossil shells is a joy. Unlike vertebrate animals which can travel through changing environments, fossil mollusks are generally restricted to specific environments and can provide researchers with information about water depth, temperatures, current direction, salinity, water clarity, and much more. Hooray for mollusks.

Carol J. Stadum

1 comment:

Doug said...

Carol is right; Mollusks Rule!

Southern coastal California provides an excellent study area for anyone interested in mollusk community evolution within varying depositional environments and doesn't mind people staring at them while digging into the hillside behind bus stops.