INTRODUCTION

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GENERAL GEOLOGIC SETTING OF GUTHRIE COUNTY

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DEVELOPMENT OF CRETACEOUS STRATIGRAPHIC NOENCLATURE IN WESTERN IOWA AND THE TYPE DAKOTA AREA

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THE LOWER DAKOTA FORMATION, NISHNABOTNA MEMBER, IN WESTERN IOWA

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FLUVIAL DEPOSITION OF THE NISHNABOTNA MEMBER

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SEDIMENT SOURCE AREAS

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MID-CRETACEOUS PALEOGEOGRAPHY ALONG THE EASTERN MARGIN OF THE WESTERN INTERIOR SEAWAY

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SUMMARY OF PENNSYLVANIAN STRATIGRAPHY IN GUTHRIE COUNTY

 

 

 

 

ROAD LOG AND STOP DESCRIPTIONS

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Stop 1.  Natural exposures of Dakota Formation in Springbrook State Park

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Stop 2.  Hwy. 25 Roadcut Exposure

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Stop 3.  Bar-L Ranch Exposure

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Stop 4.  Heiland Sand and Gravel Pit

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Stop 5.  County Sand and Gravel Pit

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Stop 6.  Middle Pennsylvanian exposure along S. Racoon River

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Stop 7.  Roadside exposure of a Pennsylvanian limestone

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