Primary textures and mineral associations in the Ultramafic zone of the Stillwater complex, Montana / by Everett D. Jackson.
| Author/creator | Jackson, Everett D. |
| Other author | United States. Department of the Interior. |
| Other author | Geological Survey (U.S.) |
| Format | Book |
| Publication Info | Washington : United States Government Printing Office, 1961. |
| Description | v, 106 pages : illustrations, map, diagrams, tables ; 29 cm. |
| Subjects |
| Portion of title | Stillwater complex, Montana |
| Series | Geological Survey (U.S.). Professional paper ; 358 Geological Survey professional paper 358. ^A16492 |
| Contents | Abstract -- Introduction -- Fieldwork, acknowledgments, and scope of report -- General geology of the complex -- Composition of the rocks -- Mineralogy -- Rock types in the Ultramafic zone -- Lithologic similarities and contrasts -- Textures of the rocks -- Primary precipitate -- Shape of the settled crystals -- Euhedra -- Subhedra and anhedra -- Discussion -- Distribution of the settled crystals -- Basal zone -- Ultramafic zone, Peridotite member -- Ultramafic zone, Bronzitite member -- Discussion -- Internal character of the settled crystals -- Inclusions -- Oriented intergrowths -- Zoning -- Fractures -- Undulatory extinction -- Grain size and grain-size distribution -- Grain size -- Sorting -- Size-density relations -- Discussion -- Orientation of the settled crystals -- Bronzite -- Olivine -- Discussion -- Relations of the primary precipitate to the interprecipitate material -- Reaction replacement -- Secondary enlargement -- Poikilitic harzburgite and dunite -- Bronzitite -- Chromitite -- Olivine chromitite and poikilitic chromite harzburgite -- Olivine bronzitite and granular harzburgite -- Volumetric relations -- Stratigraphic and areal distribution -- Discussion -- Initial porosity -- Bronzitite -- Poikilitic harzburgite -- Chromitite -- Granular harzburgite -- Olivine chromitite and poikilitic chromite harzburgite -- Discussion -- Interprecipitate material -- Shape of the intersititial material -- Shape of the interstices -- Shape of the poikilitic crystals -- Discussion -- Distribution of the interprecipitate material -- Poikilitic harzburgite -- Granular harzburgite -- Bronzitite -- Chromitite -- Olivine chromite and poikilitic chromite harzburgite -- Stratigraphic distribution -- Discussion -- Internal character of hte interprecipitate material -- Inclusions -- Oriented intergrowths -- Zoning -- Size and size distribution of poikilitic crystals -- Grain size -- Discussion -- Orientation of poikilitic crystals -- Development od dominant textures in the Ultramafic zone -- Automorphic-poikilitic texture -- Hypautomorphic texture -- Xenomorphic texture -- Development of the Ultramafic zone -- Conditions of crystallization and deposition -- Predepositional conditions -- The magma -- Primary crystallization products -- Depositional conditions -- Agents of transportation and deposition -- Origin of the layering -- Postdepositional conditions -- Character of the crystal mush -- Interprecipitate magma -- Crystallization of the interprecipitate material -- Mineral associations in the Ultramafic zone -- Primary precipitate -- Interprecipitate material -- Classification of rock products -- Significance of the depositional cycles -- Summary of salient features -- Chemical aspects -- History of the cycle -- Bottom crystallization -- Intermittent crystallization -- Intermittent magma injection -- Variable-depth convection -- Similarity to chemical sediments -- References cited -- Index. |
| Abstract | "The petrographic features and origin of the layered chromitites, bronzitites, and harzburgites in the lower part of the Stillwater complex." |
| Local note | Joyner- FOR JOYNER LIBRARY HOLDINGS OF THE SERIES, GEOLOGICAL SURVEY PROFESSIONAL PAPER, SEARCH BY CALL NUMBER QE75 .P9. |
| Bibliography note | Includes bibliographical references (pages 100-102) and index. |
| Issued in other form | Online version: Jackson, Everett D. (Everett Dale), 1925-1978. Primary textures and mineral associations in the Ultramafic zone of the Stillwater complex, Montana |
| LCCN | gs 61000195 |
| Govt. docs number | I 19.16:358 |
| Govt. docs number | I 19.16:358 c.2 |