Sierra de Álamos in Geologic Time

50… A step back in time starting with the coming of the age of mammals…

Atop Sierra de Alamos at sunrise, Alamos, Sonora, Mexico. Photo by Anders Tomlinson.

Atop Sierra de Álamos, near Gringo Point, looking south at sunrise into Sinaloa.

So much of Á is about history. In that spirit let us peek at the region’s geologic history, stand earth time. The Sierra Madre Occidental and the Rocky Mountains began to form 90 to 30 million years ago along the west coast of North America. Ocean levels were much higher than today, back then there was no Florida. The age of mammals started 66.4 million years ago. Sierra de Alamos was beginning under great pressure deep in the earth along with what would become Aduana’s silver deposits.

Granite Outcroppings on Sierra de Alamos, Alamos, Sonora, Mexico.  Photo by Anders Tomlinson

Sierra de Alamos is granite, only recently has it emerged from the earth.

Northwest Mexico, including Álamos, was buried under thousands of feet of ash, cinder and lava flows. Volcanic eruptions began 25 million years ago and continued another 12 million years, give or take a day or two. The Sea of Cortez began to form 12 to 3 million years ago as the Basin and Range block building was underway. Sierra de Álamos was still underneath a layer of all things volcanic. Over time erosion cut into ash flow plateaus creating landmarks like Barrancas del Cobre, Copper Canyon, whose materials were washed away and deposited near Sierra de Álamos. The rising mountain was still cover by blankets of earth.

View from atop Mt. al;amos looking south west, Alamos, Sonora, Mexico.  Photo by anders Tomlinson.

Atop the mountain looking southwest towards farmland and the Sea of Cortez.

As time marched on climate changed. The region began to cool 15 to 30 million years ago. Two to four million years ago it was warming up and raining. Most of the past two million years has been an ice age with 15 to 20 glacial periods. And now the planet is warming again. From a distant gallery it may look as if earth’s climate ebbs and flows like clockwork as the solar winds race past our blue planet, a molten rock with the thinest of crust and atmosphere.

Atop Mt. Alamos looking north at Alamos, Sonora, Mexico.  Photo by Anders Tomlinson.

Spring time on the mountain looking north with Alamos waking up below.

Today, Sierra de Álamos rises thousands of feet above its surroundings. And many have visited Álamos to research the region’s geology, flora and fauna. Josephine Scripps was asked by the San Diego Natural History Museum in the 1940’s to lead a group of six young men, none who spoke spanish, on a natural science expedition to Álamos. They were to bring back a rare mountain sheep’s skeleton and hide. Josphine, 1910 -1992, was the granddaughter of Edward Scripps, founder of the Scripps – Howard newspaper chain. Her life-long pursuit of collecting mineral specimens from across the planet began on that trip to Álamos.

View from Above

Mt. Álamos is some 6,500 feet above sea level. It towers 5,000 feet above the town of Álamos. It is another world, wild parrots, dry tropical forest, granite and… Up and down is a day’s effort, it is well worth it. To reach the top it is recommended to start hiking early while it is still dark and cool.
Photos and editing by Anders Tomlinson. Music from “Camino Songs” by SonicAtomics.

An introduction to a Short History of Álamos, Sonora, Mexico.

“Here is something Special”, Spanish explorer Vasquez de Coronado noted in 1540 as he headed north, passing by tall white rocks on Alamos de Sierra. This is the opening chapter to “A Short History of Álamos” written, filmed and edited by Anders Tomlinson. Narrated by Bruce Miles. Soundtrack by SonicAtomics and Estudiantina de Álamos.

Álamos shares a strong maternal bond, steeped in history, with all the Southwest.

Juan Batista de Anza arrived and departed from Álamos in the spring of 1775 with silver, and local families, to settle “Monterey and the Californias”, including San francisco. Another expedition, five years later, left Álamos to settle Los Angeles.

The conclusion to a Short History of Álamos, Sonora, Mexico embraces the Sierra Madre.

Here, Bishop Reyes’ Cathedral in the Plaza, a three-tiered belfry, shines gold in morning light. Here, looking east, one’s imagination is stirred by the forbidding beauty of the Sierra Madre Occidentals. Together, they shape the Álamos experience.

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©2013 Anders Tomlinson, all rights reserved.

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