Category Archives: Plate Tectonics

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

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 →

Posted in Geology, Plate Tectonics, Serpentine | Tagged , , | Leave a comment

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

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

Wild Idea #6743: Possible Impact Signatures in Seafloor Isochrons

Posted on June 22, 2013 by gymnosperm

Who knows from what depths the well of ideas flows? For me it is often during the liberation of rote manual work that frees some bandwidth while still requiring a minimal level of focus and blood flow to the brain. … Continue reading →

Posted in Asteroid Impacts, Geography, Geology, Magnetic Reversals, Paleogeography, Plate Tectonics, Seafloor Isochrons | Tagged , , , , | Leave a comment

Hawaii

Posted on March 3, 2013 by gymnosperm

By incredibly good luck I’ve been spending lots of time in Hawaii lately, on business no less. I stay in this unbelievable house.   One really gets the sense of being out in the middle of the ocean in Hawaii, … Continue reading →

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

California Great Central Valley as a Cretaceous Sea of Cortez

Posted on February 18, 2013 by gymnosperm

I was travelling the world as I often do in Google Earth, pondering how strange it is that the Hawaiian Seamount chain created a gravity low its entire length, when I noticed this: Probably just because gravity lows are a nice deep … Continue reading →

Posted in Geography, Geology, Gravity Anomalies, Paleogeography, Plate Tectonics | Tagged , , , , , , | 4 Comments

Ring Around Antarctica

Posted on January 8, 2013 by gymnosperm

There are lots of rings around Antarctica. Sailors know the circum-Antarctic winds as the fearsome fifties, the screaming sixties, etc. These winds are not impeded by any land and they drive the circum-Antarctic currents in the Southern Ocean. The surface currents … Continue reading →

Posted in Geography, Paleogeography, Plate Tectonics, True Polar Wander | Tagged , , , , , , , | 4 Comments

Seafloor Isochrons Place a Hard Limit on Crustal Disintegration from the Chicxulub Impact

Posted on January 6, 2013 by gymnosperm

I always thought the entire form of the Gulf of Mexico might be the crater from the Chicxulub impact reputed to have wasted the dinosaurs. My imagination runs with that name. So much to work with. Chicxyclub…well, Club Med impact … Continue reading →

Posted in Asteroid Impacts, Geography, Geology, Magnetic Reversals, Oceanography, Plate Tectonics | Tagged , , , | 1 Comment