| Id | Identification Type | Name | Description | Distinguishing Features | Tags |
|---|---|---|---|---|---|
| 115 | Lithofacies | Calcareous silt | Lithofacies comprising >50% detrital mineral material in the silt size range (4-63 microns), with calcium carbonate the most abundant secondary component.
Carbonate grains prominent but secondary; biogenic components variable but subordinate; mineral composition of detrital component depends on erosional sources and their lithologies. |
silty calcareous fine-grained |
|
| 38 | Mineral | Calcite | Transparent colorless to pale greenish. High birefringence. Rhombic or ellipsoidal euhedra, corroded grains, micritic masses most common; more rarely twins, bow-ties, dendrites, sprays. Medium relief. Occurs as inorganic precipitate in lakes, in surface water and diagenetically (including as a replacement); also irregular detrital grains and rock fragments.
Organisms with calcite skeletal components include ostracodes, some molluscs, foraminifera, coccoliths, calcareous nannoplankton, Phacotus, charophytes, peloids, microbialites. |
High-birefringence
Transparent |
carbonate Colorless Rhombic euhedral salt |
| 23 | Mineral | Chlorite | Colorless to yellow or green, transparent, generally pleochroic. Low to moderate relief. Cleavage planes frequently visible as platy layers. Very low apparent birefringence (pseudo-isotropy) because flakes settle with {001} in the plane of the slide. However, by tilting the slide very slightly (e.g., by slipping another slide under the slide) one can evaluate the true birefringence (thanks to Frank Brown, U. Utah, for the tip). Chlorite has weak birefringence and can have anomalous (purplish or brown) interference colors due to its varying chemistry. Occurs as flakes larger than surrounding material when primary, can be fibrous or granular when replacing other minerals. | Flaky
Pseudo-isotropic |
yellow green layers ragged silicate mica transparent low-birefringence |
| 144 | Contaminant | Cigarette Ash | contaminant | ||
| 16 | Mineral | Clay | |||
| 170 | Lithofacies | Clay turbidite cap | Describes the finest, suspended component of a subaqueous density-flow deposit, settled out of the water column at the end of a transport event.
Position above fining-upward sequence; grain size may be in fine silt or clay range. |
sorted fine-grained graded |
|
| 51 | Mineral | Clinoptilolite | Associated with devitrified volcanic glass. | ||
| 29 | Mineral | Clinopyroxene | Transparent colorless to green or brown. May be pleochroic from yellow to green, depending on mineralogy. Moderate birefringence. Appear as stubby prisms and subhedral to anhedral crystals. Near-90 degree perfect cleavage. Moderately high relief. | Subhedral
near-90-degree-perfect-cleavage |
ferromagnesian silicate transparent green brown pleochroic moderately-high-relief |
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