Day 1 5/31/22

Knights Ferry, Donnell Vista & Columns of the Giants
Stop #1 Willms Road near Knights Ferry. Observing the Table Mountain latite and trying to tease-out the relationship with it and the Mehrton Formation in the…
Table mountain latite. Vesicles, porphyritic texture (large white K-feldspars in microscopic dark matrix crystals) attest to its volcanic origin.
Table Mountain Latite near Willms Road.
Professor Garry Hayes weaves an entertaining narrative of the fauna that lived in the area 9-10 million years ago when the Table Mountain Latite erupted.…
While the students were geologizing, Z took an interest in some small critters in the road.
Stop #2 - Near Tulloch Reservoir on the Stanislaus River.
Notebook is sitting on meta conglomerates that are part of the Foothills Terrane and were accreted onto California from a volcanic island arc about 200Ma. So…
Meta conglomerates of Foothill Terrane.
Luckily it was very nice, not hot day to extol the virtues of the area geology.
Multiple flows and even a bit of columnar jointing of the Table Mountain latite.
A student checks-out the metaconglomerate. OID irrigation flume on the right, Stanislaus River in the center.
Serpentine at Red Hills Area of Critical Environmental Concern.
Students get a snack while listening to Garry explain the history of Red Hills and the BLM "Land of Leftovers" and the modern geology / flora that makes it such…
The rocks in the Red Hills are composes of Serpentine and have a high abundance of nickel, selenium and iron, making it very hard for plants to grow. Those that…
Pussy paws at Donnell Vista. Decomposed granite soil.
Donnell Vista! Here to see the Sierra granites (here about 87 million years old) and the 10.8Ma Table Mountain latite of the Dardanelles in the distance. How is…
Great spot for notes.
Laura happily jotting down her notes too.
Stanislaus River in bottom-center of photo. It appears most of the overlying sediments and volcanics were eroded (exposing the granites) by about 50 million…
Enclaves of mafic blobs in the Granodiorite of Kinney Lakes (at Donnell Vista).

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