Other field trips
Published:
Trilobite fragment (possibly Ollenoides serratus), Walcott Quarry member of the Burgess Shale, British Columbia
Large vertical burrows in the Early Cambrian Upper Wood Canyon formation near Emigrant Pass, California
A view of the Ediacaran-Cambrian stratigraphy of the southern Nopah Range, CA, with the Ediacaran Johnnie Formation (including the prominent yellow-orange marker bed of the Johnnie Oolite) overlain in turn by the Sterling Quartzite and the Wood Canyon Formation.
The Johnnie Oolite, composed of spherical millimeter-scale ooids, as exposed in the southern Nopah Range, California.
“Tubestone” texture in the ~635 Ma Noonday Dolomite (generally interpreted as a Marinoan cap carbonate) near the eponymous Noonday Mine in the southern Nopah Range, CA.
Sheet-crack cements in the ~635 Ma Noonday Dolomite (generally interpreted as a Marinoan cap carbonate) near the eponymous Noonday Mine in the southern Nopah Range, CA.
Paleoproterozoic basement orthogneiss (~1.7 Ga, dark exposures in the foreground) overlain by a thin Cryogenian lodgement till of the Kingston Peak formation (tan and brown), in turn overlain by the cliff-forming Noonday Dolomite. The Kingston Peak formation has been significantly altered by much later hydrothermal activity in this locality near the Noonday Mine in the southern Nopah Range, CA.
Assorted clasts (primarily Paleoproterozoic basement, including one orthogneiss clast here featuring prominent ptygmatic folds) in the matrix of the Cryogenian diamictite of the Kingston Peak Formation near Saratoga Spring, California. The surface, especially including that of some of the darker clasts towards the bottom of the field of view, is variably ventefacted from modern exposure.
A group of geologists walks towards the contact between the Kingston Peak Formation (dark diamictites, left) and the Noonday Formation (tan dolomite, right) near Saratoga Spring, California.
The Noonday Dolomite, interpreted as a Marinoan cap carbonate, overlies the Cryogenian diamictites of the Kingston Peak Formation near Saratoga Spring, CA.
Partly-silicified giant ooids of the Tonian Beck Spring formation near Saratoga Spring, CA.
Tonian carbonates of the Horsetheif Springs formation near Saratoga Spring, CA.
Laminated calcitic cements in the Mesoproterozoic Crystal Spring Formation near Saratoga Spring, CA.
Clarks Fork Canyon, where the Clarks Fork Yellowstone River incises into uplifted Archean Wyoming Province basement in the Beartooth Mountains, WY. The plateau at the top of the canyon is locally nonconformably overlain by Cambrian Flathead Sandstone.
A bedding plane of stromatolitic limestone in the Carboniferous Amsden Formation, near Shell Canyon, WY.
A side view of stromatolitic limestone in the Carboniferous Amsden Formation, near Shell Canyon, WY.
The colorful Cretaceous stratigraphy of Devil’s Kitchen, near Cody, WY.
Intrusive breccia in the mixing zone of the 149 Ma Guadalupe Igneous Complex, Sierra Nevada, California
Ball-and-pillow features alongside flame structure in the mixing zone of the Guadalupe Igneous Complex, Sierra Nevada
Boudinage in mylonite shear zone near the base of the Guadalupe Igneous Complex, Sierra Nevada
Ladder dike in the Half Dome Granodiorite, Yosemite —
Detail of ladder dike in the Half Dome Granodiorite, Yosemite
Nearly circular mafic enclave in the Half Dome Granodiorite, Yosemite
Glacially-carved granite domes near Tenaya Lake, Yosemite
Tufa, Mono Lake, California
Paleoproterozoic (~1.7 Ga) migmatitic basement forms a jagged arête at the head of Mayflower Gulch, Tenmile Range, Colorado.
Intricate fluting and spatter on the wall of a lava tube, Raufarhólshellir, Iceland
Ice stalgmites in Raufarhólshellir lava tube, Iceland
Intrusive breccia at Island Lake, Sierra Nevada
Large orthoclase crystals in pegmatite near Island Lake, Sierra Nevada. Camera filter is 4 cm for scale.
Glacially-polished columnar jointing, Devil’s Postpile, California
Meter-scale columnar jointing in the main flow of the Bishop Tuff, Owens Valley, California
Airfall ash and pumice from the Bishop Tuff, Owens Valley, California
Students climb one of the tallest sand dunes in North America - Eureka Dunes, Death Valley
Colorful stratigraphy of the Mesoproterozoic Crystal Spring Formation, Tonian Horse Thief Springs Formation and Tonian Beck Spring Dolomite near Beck Spring, Kingston Range, California
Meter-wide magnetite veins cutting Mesoproterozoic dolomite of the Crystal Spring Formation near Beck Spring, Kingston Range, California
Detail of magnetite vein cutting Mesoproterozoic dolomite of the Crystal Spring Formation near Beck Spring, Kingston Range, California
Intricate contact of magnetite with surrounding dolomite, Beck Spring region, Kingston Range, California
Comb layering in the Adamello Pluton, Italian Alps.
A magmatic contact between tonalite and enclave-rich granodiorite is offset by a magmatic shear zone, Adamello Pluton, Italy
Ductile marble flows around fractured and offset quartzite in the metamorphosed sedimentary section south of the Adamello pluton, Italy
Vesicle escape tubes in the Taos Plateau Basalt, Rio Grande Rift, New Mexico
Large modern dessication cracks, Argentine Precordillera
Syn-rift sediments, Argentine Precordillera
Colorful syn-rift sediments in the foreground of the main Andean Cordillera, Argentina