Serpentine meshwork in Josephine peridotite

Click on the image to enlarge.            Photo © Daniel R. Snyder

Josephine peridotite, partially serpentinized. A component of the Josephine ophiolite sequence. Serpentine meshwork occupies space between grains and along fractures within individual grains. Because serpentine can't accommodate the iron given up by the olivine, this is taken up as hematite, which gives the meshwork its brown color. Josephine County, southwest Oregon. XPL Imaged area 1.3 mm x 2 mm.

Josephine peridotite - hand samples

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Polished section (left) and rough hand sample (right) of Josephine peridotite, a component of the Josephine ophiolite sequence, southwest Oregon and northwest California. Dark grains in polished section (also slightly darker grains in rough hand sample) are orthopyroxene, remainder is olivine. Light areas around edges are weathered rind; white lines are saw marks. Josephine County, Oregon. Scale in centimeters.

Josephine peridotite (harzburgite) - Full thin section in cross-polarized light

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It looks much better close up.                      Photo © Daniel R. Snyder

Josephine peridotite, a component of the Josephine ophiolite sequence. Small, brightly colored grains are olivine, larger grains in shades of gray are orthopyroxene.  Josephine County, southwest Oregon. XPL macrophotograph of entire thin section. Imaged area 18 mm x 38 mm.

Josephine peridotite - digital mosaic

Ckick on image to enlarge.          Photo © Daniel R. Snyder

In this image: mostly olivine (bright colors) with incipient serpentinization, and a few large (gray) grains of orthopyroxene. Josephine peridotite, a component of the Josephine ophiolite sequence. Klamath Mountains, Josephine County, southwest Oregon. Digital mosaic of four 2x-objective images. XPL. Imaged area 5.1 mm x 7.6 mm.

Josephine peridotite (harzburgite) - pyroxene

Click on image to enlarge.           Photo © Daniel R. Snyder

Josephine peridotite (partially serpentinized harzburgite), a component of the Josephine ophiolite sequence. Gray grain at left is pyroxene, large gray grain in center is partially serpentinized pyroxene (bastite texture). Brightly colored grains are olivine. Klamath Mountains, Josephine County, southwest Oregon.  XPL. Imaged area 1.3 mm x 2 mm.