Browse Items (1651 total)

Kingdom: Animalia Phylum: Porifera Class: Demospongea Order: Lithistida Family: Astylospongiidae Genus: Astylomanon Species: cratera

Kingdom: Animalia Phylum: Porifera Class: Demospongea Order: Lithistida Family: Cylindrophymatidae Genus: Heliospongia Species: ramosa

Kingdom: Animalia Phylum: Porifera Class: Demospongea Order: Orchocladina Family: Astylospongiidae Genus: Astylospongia Species: praemorsa

Kingdom: Animalia Phylum: Porifera Class: Demospongea Order: Dictyoceratidae Family: Spongiidae Genus: Euspongia Species:

OCR PDF of supplemental information for the Barrovian Metamorphic Sequence--Dutchess County, NY

This unique rock contains white crystalline wollastonite, brown grains of andradite garnet, and green diopside. Specimens courtesy of R.R. Bauer, plant manager of NYCO MInes (1980). McLelland reports some grossularite in addition to andradite.

The…

Metamorphised Balmville limestone with visible phlogopite crystals. Also contains tremolite visible at the outcrop level. Within nose of anticline of Walloomsac schist.

The PPL thin section shows a large irregular calcite grain with tremolite at…

Metamorphised Balmville limestone with visible phlogopite crystals. Also contains actinolite.

Thin section shows calcite with interspersed pleochroic phlogopite.

Metamorphised Briarcliff dolostone with visible micas. Contains diopside, tremollite, and phlogopite. At the metamorphic grade of the first sillimanite isograd.

Thin section shows irregular dolomite grains in the center, with pleochroic…

Metamorphised Briarcliff dolostone.

The thin section shows well-twinned dolomite grains with diopside at the bottom.

Extremely coarse-grained muscovite schist. Large garnets visible in hand sample. Sillimanite is not recognizable in hand sample, however.

The thin section shows muscovite (with minor sillimanite) in a large band, biotite, staurolite, and…

Schist with coarse biotite controlling foliation. Garnets visible in some hand samples. Kyanite blades without preferred orientation--at higher concentration within folds. Possibly from the Walloomsac schist.

The PPL thin section shows biotite,…

Metamorphised sandstone with a gray, glassy appearance. From the Paughquag quartzite, a late Cambrian formation. The basal Cambrian quartzite rests on pre-Cambrian gneisses.

The thin section shows quartz and plag with some biotite and grain…

Schist with coarse staurolite grains. This outcropping is approximately on the strike of the chloritoid schists (sample 7). Also contains garnet, muscovite, feldspar, and quartz. Presumed to be from the Everett Schist.

The thin section shows…

Schist bearing both staurolite and chloritoid. This marks the first appearance of staurolite in the metamorphic sequence. Also contains garnet, muscovite, chlorite, biotite, feldspar, and quartz. The assemblage in not in equilibrium.

The thin…

Schist with coarse chloritoid crystals (up to 1/8 inch) without preferred orientation. These crystals grow across the foliation developed in the schist, but appear deformed. Chloritoid is a silicate mineral made in metamorphism. It also contains…

Schist with sparse garnet. This schist is darker and graphitic. It also contains biotite, chlorite, muscovite, feldspar, and quartz.

The thin section shows several large biotite grains with an included garnet, small quartz grains, muscovite, and…

A highly graphitic slate in the Walloomsac slates. Contains pyrite. This rock also contains biotite, chlorite, muscovite, quartz, ilmenite, and pyrite.

The thin section shows large biotite grains, and chlorite muscovite, and quartz. Fluid…

Kink fold in a slate from the Mt. Merino Member.

This rock is from the chlorite zone of the Barrovian metamorphic sequence (low metamorphism).

The graywacke facies in the Mt. Merino member (where sample 4 also comes from). Graywacke is a hard, dark-colored sandstone. This sandstone represents a similar rock to the protolith for the quartzite of sample 10.

The thin section shows quartz,…