Browsing by Subject "rocks"

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    Bulletin No. 2. Preliminary Description of the Peridotytes, Gabbros, Diabases and Andesytes of Minnesota
    (Minnesota Geological Survey, 1887) Wadsworth, M.E.
    It is proposed in the following pages to give a preliminary description of certain types of Minnesota rocks, to serve as a framework for a more complete discussion of the same in the final report. The field relations and to some extent the microscopic characters of the rocks described in the following pages have been given by the state geologist in the annual reports for 1879, 1880, and 1881, and in volume I of the final report. In some cases it will be found that the field relations have led the state geologist to different conclusions concerning the nature of the rocks in question from those adopted by the writer, who has based his views upon the correlation of the microscopic characters of rocks and their field relations, as studied by him elsewhere.
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    Bulletin No. 37. Minnesota's Rocks and Waters A Geological Story
    (Minnesota Geological Survey, 1954) Schwartz, George M.; Thiel, George A.
    This volume has been prepared in an attempt to make available to the citizens of Minnesota a general summary of the major geological features of the state and to stimulate a greater interest in, and appreciation of, their natural surroundings. Ability to interpret the landscape requires knowledge of the forces that produced it. One may admire the beauty of a waterfall or marvel at its grandeur, but to appreciate it fully, one must know how it was formed. Man draws from the earth many materials which are necessary for life and happiness, and he deals with geological conditions in many of his daily activities. For example, he plows the soil, which is composed largely of weathered rock materials, and cuts the surface rocks as he grades roads and railroads and excavates foundation places for his skyscrapers and his great plants in which to exploit the earth's resources. Yet how many of the thousands of citizens of Minnesota employed in these enterprises understand the geological relationships of the materials with which they labor? How much greater would be their interest in their assigned tasks if they knew more about the formation of the materials which occupy their attention? An understanding of geological processes guides us in the search for mineral resources and aids us in understanding the forces which produced them. Soil erosion, one of our most important problems, is closely related to the geology of the area involved. The resources of any region determine to a marked degree the activity of its inhabitants. They are the foundation of our well- being, the hope of our future. Minnesota, though known as an agricultural state, has great mineral wealth, and many of its citizens are engaged in mineral industries. All of the mineral substances produced from the rocks of the state may be classified as industrial minerals even though some are metals and others nonmetals. :Metal mining is restricted to the iron ranges, but the nonmetals include a great variety of materials-such as limestone for agricultural lime. marl, sand and gravel, clays and shales, wool rock, and structural and architectural stone-which are excavated and processed at many places in the state. The authors of this book have had many years of experience in educational work in Minnesota. It is their opinion, based upon observation and experience, that in the curriculums in our schools not enough time is devoted to a study of our own state and its resources. It is hoped that this volume will furnish science teachers 'with accurate information which they can in turn pass on to their students at the appropriate time, and that citizens at large will find it a source of information regarding their state. Technical terms have been held to a minimum in order to make the text intelligible to those unfamiliar with detailed geological terminology. The authors know that this method inevitably results in generalities that may not always take into account all detailed scientific information available to the geologist. We hope, however, that geologists will recommend the book to their friends and that they will not hesitate to explain some of the exceptions that are bound to appear where such broad generalizations are employed for the sake of simplicity. Geology is the science that weaves all the other natural sciences together into a comprehensive whole and this results in great complexity. The authors, with full awareness of the magnitude of the task, have attempted to resolve complex geological details by employing a nonscientific assistant who screened out much of the detail and obtained a residue that is sufficiently free of technicalities to be comprehensible to the general reader.
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    Bulletin No. 37. Minnesota's Rocks and Waters A Geological Story
    (Minnesota Geological Survey, 1963) Schwartz, George M.; Thiel, George A.
    This volume has been prepared in an attempt to make available to the citizens of Minnesota a general summary of the major geological features of the state and to stimulate a greater interest in, and appreciation of, their natural surroundings. Ability to interpret the landscape requires knowledge of the forces that produced it. One may admire the beauty of a waterfall or marvel at its grandeur, but to appreciate it fully, one must know how it was formed. Man draws from the earth many materials which are necessary for life and happiness, and he deals with geological conditions in many of his daily activities. For example, he plows the soil, which is composed largely of weathered rock materials, and cuts the surface rocks as he grades roads and railroads and excavates foundation places for his skyscrapers and his great plants in which to exploit the earth's resources. Yet how many of the thousands of citizens of Minnesota employed in these enterprises understand the geological relationships of the materials with which they labor? How much greater would be their interest in their assigned tasks if they knew more about the formation of the materials which occupy their attention? An understanding of geological processes guides us in the search for mineral resources and aids us in understanding the forces which produced them. Soil erosion, one of our most important problems, is closely related to the geology of the area involved. The resources of any region determine to a marked degree the activity of its inhabitants. They are the foundation of our well- being, the hope of our future. Minnesota, though known as an agricultural state, has great mineral wealth, and many of its citizens are engaged in mineral industries. All of the mineral substances produced from the rocks of the state may be classified as industrial minerals even though some are metals and others nonmetals. :Metal mining is restricted to the iron ranges, but the nonmetals include a great variety of materials-such as limestone for agricultural lime. marl, sand and gravel, clays and shales, wool rock, and structural and architectural stone-which are excavated and processed at many places in the state. The authors of this book have had many years of experience in educational work in Minnesota. It is their opinion, based upon observation and experience, that in the curriculums in our schools not enough time is devoted to a study of our own state and its resources. It is hoped that this volume will furnish science teachers 'with accurate information which they can in turn pass on to their students at the appropriate time, and that citizens at large will find it a source of information regarding their state. Technical terms have been held to a minimum in order to make the text intelligible to those unfamiliar with detailed geological terminology. The authors know that this method inevitably results in generalities that may not always take into account all detailed scientific information available to the geologist. We hope, however, that geologists will recommend the book to their friends and that they will not hesitate to explain some of the exceptions that are bound to appear where such broad generalizations are employed for the sake of simplicity. Geology is the science that weaves all the other natural sciences together into a comprehensive whole and this results in great complexity. The authors, with full awareness of the magnitude of the task, have attempted to resolve complex geological details by employing a nonscientific assistant who screened out much of the detail and obtained a residue that is sufficiently free of technicalities to be comprehensible to the general reader.
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    OFR20-01, Minnesota Data Preservation Report for 2019/2020: Updated Data Inventory, Preservation of Pillsbury Hall Rock Collections and Documentation, Assembly of Mineral Potential Related Information
    (Minnesota Geological Survey, 2020) Thorleifson, L Harvey
    Minnesota Geological Survey (MGS) activity is focused primarily on recommendations of Legislative panels that indicate that statewide coverage of layered County Geologic Atlases will be needed to support management of water resources, while concurrently being needed for applications such as mineral resources, engineering, hazards, and research. All MGS activity is reliant on geological specimens, as well as geological, geophysical, and geochemical data. The MGS long-term data preservation plan prepared in 2009 identified the highest priorities in relation to applications such as groundwater management and mineral resource assessment. Included were: 1) reprocessing of the aeromagnetic database; 2) enhancement of location precision for gravity stations; 3) vertical georeferencing of the rock property database; 4) cataloging and georeferencing of rocks and thin sections stored at the building MGS occupied from 1983 to 2015; 5) standardized formats for existing databases; and 6) scan and web enable all publications. More recently, a need was recognized for: 7) scanning, digitizing, and enhanced cataloging of borehole geophysical records, 8) comprehensive regional geophysical survey rescue, 9) enhancements to the cuttings collection and database. Objectives 1, 2, and 3 were completed with State of Minnesota support. Objective 4 was completed with multiple years of NGGDPP support. Objective 5 is ongoing. Objective 6 was completed with University of Minnesota Library support. Objective 7 was completed for gamma logs with our 2015 NGGDPP grant, and was completed for all borehole geophysical logs due to 2017 NGGDPP support. Geophysical survey rescue will remain unfulfilled due to staff availability constraints. Work on cuttings will be carried out due to NGGDPP support during 2020/2021.