Pleistocene bones abound beneath the Fairmead landfill near Chowchilla. See them at the Fossil Discovery Center of Madera County. Photos by Andrew Alden

My previous side trips from I-5 have involved rocks, but that's not all there is to geology. This suggested route, an alternative to taking I-5 straight south to Los Angeles, will expose you to the southern Great Valley's hydrology and many excellent, recently excavated fossils.

Start by exiting at Santa Nella — not to patronize the garish set of businesses there, but to take state route 152 east. You'll go all the way across the valley to Route 99, then south from there to the "Grapevine".

The first thing you'll notice, if you haven't already, is the profusion of canals in the Valley. They come in all sizes, ranging from the Edmund G. Brown Aqueduct (that's the first one you cross) down to uncountable numbers of field ditches. There are natural streams, but most of the water you'll see is in canals. This one runs parallel to the San Joaquin River about 6 miles west of Dos Palos Y.

Right next to it, the river that gave its name to the San Joaquin Valley was a sandy ditch in March during the rainy season. In good weather you'll be able to see mountains wherever you are, either the Coast Range on the west or the Sierra Nevada on the east (as seen here). I believe that there is no place in California where mountains are not visible if the air is clear.

The far end of route 152 meets Route 99. I recommend the old-timey charm of Chowchilla just north of here for a road stop, but otherwise you'll turn south on 99 and take the very first exit to the Fossil Discovery Center of Madera County.

Photo courtesy Tsing Bardin

The center is across the road from a sanitary landfill, and for a good reason: in 1996, diggers at the new Fairmead landfill uncovered a complete mammoth tusk. Soon it was realized that the site contained a world-class Irvingtonian fossil fauna dating from the mid-Pleistocene about half a million years ago. (There's a Bay Area connection here: the Irvingtonian is named for the wonderful bone beds unearthed in the East Bay's Irvington district during freeway construction in the 1940s.)

A paleontological foundation was set up and scientific ties established at nearby Cal State Fresno. Whenever the landfill operators open up a new pit, fossil scientists are on hand to harvest what they can. Bones of mammoths, wolves, sabertooth cats, horses, camels, ground sloths and many smaller creatures are stockpiled and studied at leisure between digs. The Fossil Discovery Center opened its doors in late 2010 and makes an excellent visit whatever your level of interest or expertise. Its outdoor "Pleistocene Water Source" exhibit makes it easy to imagine the lush scene in ancient times.

You can sit out back, next to the fossil washing station, and cast your eye over the surrounding land. I was told that the center has options on some of this acreage, where thousands more fossils surely lie in wait.

Eventually you'll need to return to 99 and resume your journey. Another stop you should consider is in Bakersfield, where less than 5 miles east of the road on Stockdale Highway is the city's gracious new Riverwalk Park on the Kern River, which is still a vigorous stream here.

Bakersfield has a lot going on. Another spot to consider visiting is the Buena Vista Museum of Natural History, home of superb fossils from nearby Sharktooth Hill.

GeoZeum is a brand-new boutique education center of geology in historic—and geologically rich—San Juan Bautista. Photos by Andrew Alden.

Most of us have a retirement dream: What would we do once our daily grind is over? Retired geologists I know indulge their devotion to poetry, photography, winemaking, philosophy, or Burning Man. A common idea is to open a little rock shop. Phil Stoffer is a born teacher with a huge rock collection, and his retirement project is to run a little museum in San Juan Bautista, a superb place to personally introduce the pleasures and treasures of Earth science to all comers. "It's all about keeping geology going," he says. I have seen nothing like it before.

Stoffer has dipped into a lot of the geologist's typical career options: mining, oil and gas, scientific librarian, college instructor, and website creator and field hand for the U.S. Geological Survey. He's collected rocks and fossils and photographed geology in all fifty states. All of that, experience and photos and specimens, is the nucleus of Stoffer's GeoZeum, just a short stroll from the San Andreas fault and, of course, on the Web.

Some of the best rocks in GeoZeum are found near San Juan Bautista.

GeoZeum has shelves of rocks, minerals and fossils. It also has tables covered with them, meant to be handled. It has an earthquake machine and a tsunami tank. It has big 3D photos of landforms and glasses to view them with. It even has a closet filled with fluorescent minerals. A lapidary lab is in the planning stage. And the key ingredient is the owner, eager to show and tell.

A project like GeoZeum relies on a lot of synergy. First, there's the Spanish mission in San Juan Bautista. California's unique 4th-grade curriculum emphasizing the missions brings busloads of children to San Juan Bautista. The city itself is a draw for tourists, too. The mission owes its very location to the scarp raised along the San Andreas fault, and more than any other California mission its history is tied to earthquakes.

The San Andreas fault runs along the foot of the rise on which the San Juan Bautista mission sits. GeoZeum's Phil Stoffer leads walks here every weekend.

Second, GeoZeum shares a building with TOPS A Rock Shop, an uncommonly well-stocked example of its genre. TOPS will be a natural gathering place for the rock-and-mineral club that Stoffer is launching.

Third, San Juan Bautista is a remarkable nexus of geological sites every bit as interesting as the Bay Area. Indeed, just a million years ago you could say the area was the Bay Area, because the rivers of the Central Valley reached the Pacific through here. The area is full of mines and quarries, several earthquake faults, and diverse packages of rocks that those faults have carried here from far away. The GeoZeum website has a lot of maps and other material about the area.

One of Stoffer's favorite places is the riverbed of the San Benito River, where the gravel contains an enormous variety of rock types. But when I visited him earlier this week, we went instead to Gabilan (Fremont) Peak and explored some old barite mines in the ancient marble that makes up the mountaintop. We brought along ultraviolet flashlights and admired the veins of blue and yellow fluorescence in the mine passages. Stoffer has dozens of ideas like these for geologic walks.

GeoZeum is already operating Thursday through Sunday, but its formal Grand Opening is October 15. Stoffer will welcome you to his museum, whether you're a kid, a fellow retired geologist or anything between. Just look for the dinosaur tracks on the sidewalk.

Often at the California Academy of Sciences, you will see docents out on the floor of the museum with an example from our live animal collection.

You've probably heard of this bacteria before, as an unpleasant bug that sometimes finds its way into high-protein foods such as meat, fish, and eggs. It is also naturally found on and in many reptiles, and does not usually make the animals sick, but if passed to humans– particularly young children, the elderly and infirm — it can cause a serious infection called Salmonellosis.

But selecting the right anti-microbial was not as easy a choice as we thought it would be.

Food and Drug Administration published reports question the use of antibacterial soap and hand sanitizers, saying that it found no medical studies that showed a link between a specific consumer antibacterial product and a decline in infection rates. Plus, regular soap kills 90% of bacteria and leaves little impact on the environment.

Additionally, anti-bacterial products like Purell use synthetic polymers known as Triclocarban and triclosan to kill off bacteria. Triclosan is known to promote the growth of resistant bacteria, including E. coli, and both pose environmental toxicity risks; after washing your hands or washing the dishes they can get into the waste water system. Because they do not break down or get filtered out during waste water treatment, up to 75 percent of the original amount gets into the Bay. Once in the environment, these products have been known to disrupt the health of marine life and other wildlife.

So Academy scientists went in search of an alternative product that does not contain the above 2 agents, and has recommended Vionex Antimicrobial Soap for our public programs. Commonly used in the medical, dental, and law enforcement industries, Vionex uses a different antimicrobial agent called PCMX, or parachlorometaxylenol, which is considered significantly less toxic to humans and other mammals that Triclocarban and Triclosan.

What you can do at home

Even if you are not handling reptiles daily like we are, you can take action to reduce exposure to toxic anti-microbials. Whenever possible avoid products that are labeled “anti-bacterial.” Products that are likely to be anti-bacterial are most hand-sanitizers, hand wipes, cleaning products, and dishwasher detergent. If you must use hand-sanitizers, consider natural ones such as Hand-Sanz (found at Whole Food or Bristol Farms).

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