Category Archives: Geology

Sorting Rocks

Posted on December 1, 2013 by gymnosperm

Here at the gymnosperm/trunkmonkey research institute we have been spending a lot of time sorting rocks. It is utter drudgery and we would have quit a long time ago had the results not been so intriguing. Basically, we belatedly discovered … Continue reading →

Posted in Geography, Geological Evolution of the Western United States, Geology | Tagged , , , | Leave a comment

The Pacific Triangle

Posted on November 24, 2013 by gymnosperm

The triangle is formed by lines of equal age in the ocean floor derived from bands of alternating magnetism as the earth’s pole flipped. It is one of the great mysteries discussed previously. The ocean floor gets progressively older from all … Continue reading →

Posted in Geography, Geology, Pacific Triangle, Paleogeography, Plate Tectonics, Seafloor Isochrons | Tagged , , , , | 3 Comments

Follow the Granite

Posted on November 3, 2013 by gymnosperm

Granite is the currency in the construction of continents. Here we will time step through the existing surface expression of granites and related igneous and metamorphic rock in the Western US from the Archean to the present. Sediments are boring. … Continue reading →

Posted in Geography, Geological Evolution of the Western United States, Geology, History of Life, Paleogeography | Tagged , , , | 3 Comments

The Primacy of Vulcan

Posted on October 27, 2013 by gymnosperm

In the beginning there was a great flash of light, and soon there was the primal proton, Hydrogen, which fused to produce Helium , and so on, within supernovae, to create our pantheon of elements. Honestly, we need to muster … Continue reading →

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Serpentine and the Primordial Subduction

Posted on October 19, 2013 by gymnosperm

Serpentine is the California State Rock. The effluent of toxic mud volcanos might seem a strange choice for a state rock, but the related higher grade blue and greenschist metamorphism has produced eerily beautiful rocks with sinuous veining from which … Continue reading →

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Yellowstone Hot Spot, Or Not

Posted on October 12, 2013 by gymnosperm

Besides the ocean spreading ridges there are several mysterious “hot spots” evident in seamount chains where volatile components of the mantle emerge at a point as a more or less continuous volcano. The most famous of these is the Hawaiian/Emperor … Continue reading →

Posted in Geography, Geological Evolution of the Western United States, Geology, Paleogeography, Plate Tectonics | Tagged , , | Leave a comment

Circumnavigating Mount Whitney

Posted on October 3, 2013 by gymnosperm

In five decades of mountaineering in the Sierra Nevada, the wilderness has changed from a wild west dominated by cowboys and pack trains to a highly regulated theme park with lotteries for permits to visit the most desirable locations. With … Continue reading →

Posted in Anthropology, Geography, Geology, Mount Whitney, Wilderness | Tagged , , , , , | 1 Comment

Late Cretaceous Orogenic North American Continental Margin

Posted on September 22, 2013 by gymnosperm

A huge problem with geological maps is that their daunting psychedelic maze of colors makes it very difficult to bear down on specific features. We recently discovered a GIS series of State scale maps from USGS  where it is possible to … Continue reading →

Posted in Geography, Geology, Gravity Anomalies, Paleogeography, Plate Tectonics | Tagged , , | 1 Comment

Gravity Signals of Extensional Sialic Crustal Regimes

Posted on September 15, 2013 by gymnosperm

I have always loved the poorly named Great Basin of the Western United States. Yes, its maze of lowlands held a lot of glacial meltwater during the last glacial maximum before letting it percolate out to the Columbia and the Sea … Continue reading →

Posted in Geography, Geoid, Geology, Gravity Anomalies, Plate Tectonics | Tagged , , , , , , , | Leave a comment

The Hawaiian/Emperor Seamounts and How Island Arcs are Formed

Posted on September 5, 2013 by gymnosperm

Ever wonder why offshore island arcs should form at random spots in the oceans? No? Don’t worry, its a far fig newton. We offer here the suggestion that the locations are not random, that island arc trenches and probably spreading ridges and … Continue reading →

Posted in Geography, Geology, Gravity Anomalies, Seamount Chains as Incipient Island Arcs | Tagged , , , | 1 Comment