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GEOLOGY of the UPPER CRETACEOUS HORNBROOK FORMATION, OREGON and CALIFORNIA Editor

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GEOLOGY of the UPPER CRETACEOUS HORNBROOK FORMATION, OREGON and CALIFORNIA Editor GEOLOGY OF THE UPPER CRETACEOUS HORNBROOK FORMATION, OREGON AND CALIFORNIA Editor TOR H. NILSEN U.S. Geological Survey Menlo Park, California September 28-30, 1984 Published by The Pacific Section Society of Economic Paleontologists and Mineralogists Los Angeles, California U.S.A. Geology of the Upper Cretaceous Hornbrook Formation, Oregon and California, 1984 Copyright © 2012 Pacific Section, SEPM (Society for Sedimentary Geology) For copies of this volume, write to: Treasurer, Pacific Section S.E.P.M. P.O. Box 10359 Bakersfield, CA 93389 Copyright© 1984 by the Pacific Section, Society of Economic Paleontologists and Mineralogists COPYRIGHT The papers in this volume were prepared for presentation at the 1984 fieldtrip of the Pacific Section of the Society of Economic Paleontologists and Mineralogists, held in Ashland, Oregon, September 28-30, 1984. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior writtten permission of the copyright owner. Printed by Comet Reproduction Service Santa Fe Springs, CA 90670 Pacific Section Society of Economic Paleontologists and Mineralogists Field Trip Leaders TOR H. NILSEN U.S. Geological Survey Menlo Park, California MONTY A. ELLIOTT Southern Oregon State College Ashland, Oregon Pacific Section SEPM Officers - 1984 PRESIDENT ROBERT E. GARRISON University of California, Santa Cruz, California VICE PRESIDENT JEFFREY MOUNT University of California, Davis, California SECRETARY CHRISTINE CARLSON U.S. Geological Survey, Menlo Park, California TREASURER PAUL F. BERTUCCI Chevron, U.S.A., Concord, California PAST PRESIDENT KENNETH A. PISCIOTTO SOHIO Petroleum, San Francisco, California PRESIDENT ELECT J. ALAN BARTOW U.S. Geological Survey, Menlo Park, California MANAGING EDITOR REINHARD SUCHSLAND DEPCO, Inc., Bakersfield, California PREFACE AND ACKNOWLEDGEMENTS This field trip guidebook to the Upper Cretaceous Hornbrook Formation of north-central California and southwestern Oregon has been prepared for the Annual Fall Field Trip of the Pacific Section of the Society of Economic Paleontologists and Mineralogists (SEPM), to be held in Ashland, Oregon, September 28-30, 1984. This field trip is the northernmost annual field trip held by the Pacific Section—almost all previous trips have been in the areas of either central or southern California. I am thankful to the executive council of the Pacific Section SEPM for their support, encouragement, and willingness to extend the geographic limits of their annual field trips and, in particular, for their attempts to include the geologic community of the Pacific Northwest in the planning of the trip. I am especially indebted to Kenneth Pisciotto, Steven Graham, Robert Garrison, Virgil Frizzell, Alan Bartow, Paul Bertucci, Jeffrey Mount, Reinhard Suchsland, and Christine Carlson of the Pacific Section for their help and support in organizing the field trip and preparing the guidebook. The field trip co-leader, Monty Elliott of Southern Oregon State College (SOSC), also undertook the responsibility of initially organizing lodging, meals, transportation, tickets to the Shakespeare Festival, and lecture halls, and is due many thanks. Ralph Golia and Greg Barats helped during various stages of the field trip organization, and Jan Zigler has carefully edited most of the papers and provided invaluable assistance in all stages of the guidebook preparation. The Ashland area is certainly a beautiful one that provides many exciting opportunities for both cultural, educational, and outdoor activities. I hope that, within the framework of the field trip, the exciting geology of the area will add to your enjoyment of it. "I have thrust myself into this maze, Haply to wive and thrive, as best I may." The Taming of the Shrew, Wm. Shakespeare Tor H. Nilsen Contents Page INTRODUCTION TO FIELD TRIP Tor H. Nilsen 1 DESCRIPTION OF FIELD TRIP STOPS AND ROADLOG, UPPER CRETACEOUS HORNBROOK FORMATION, SOUTHERN OREGON AND NORTHERN CALIFORNIA Tor H. Nilsen 9 GEOLOGIC AND GEOGRAPHIC SETTING OF THE HORNBROOK FORMATION, OREGON AND CALIFORNIA Monty Elliott 43 STRATIGRAPHY, SEDIMENTOLOGY, AND TECTONIC FRAMEWORK OF THE UPPER CRETACEOUS HORNBROOK FORMATION, OREGON AND CALIFORNIA .... Tor H. Nilsen 51 AGE AND CORRELATION OF THE CRETACEOUS HORNBROOK FORMATION, CALIFORNIA AND OREGON W.V. Sliter, D.L. Jones, and C.K. Throckmorton 89 SANDSTONE PETROGRAPHY OF THE UPPER CRETACEOUS HORNBROOK FORMATION, OREGON AND CALIFORNIA Ralph T. Golia and TorH. Nilsen 99 CONGLOMERATE CLAST COMPOSITION OF THE UPPER CRETACEOUS HORNBROOK FORMATION, OREGON AND CALIFORNIA Greg M. Barats, TorH. Nilsen and Ralph T. Golia 111 GEOCHEMISTRY OF COAL FROM THE DITCH CREEK SILTSTONE MEMBER OF THE HORNBROOK FORMATION, NORTHERN CALIFORNIA Jan L. Zigler and TorH. Nilsen 123 POROSITY, PERMEABILITY, AND DIAGENESIS OF SURFACE SAMPLES OF SANDSTONE FROM THE HORNBROOK FORMATION C.W. Kreighin andB.E. Law 129 THE PETROLEUM SOURCE-ROCK POTENTIAL OF THE UPPER CRETACEOUS HORNBROOK FORMATION, NORTH-CENTRAL CALIFORNIA AND SOUTHWESTERN OREGON B.E. Law, D.E. Anders and T.H. Nilsen 133 STRATIGRAPHY AND SEDIMENTOLOGY OF THE OSBURGER GULCH SANDSTONE MEMBER OF THE UPPER CRETACEOUS HORNBROOK FORMATION, NORTHERN CALIFORNIA AND SOUTHERN OREGON M.T. Gaona 141 LATE CRETACEOUS TRANSGRESSIVE SEDIMENTATION: A COMPARISON OF THE BASAL HORNBROOK FORMATION AND THE CAPE SEBASTIAN SANDSTONE, NORTHERN CALIFORNIA AND SOUTHWESTERN OREGON Joanne Bourgeois 149 TECTONOSTRATIGRAPHIC TERRANES IN SOUTHWESTERN OREGON M.C. Blake, Jr. 159 GEOLOGY OF THE KLAMATH MOUNTAINS NEAR YREKA, CALIFORNIA N. Mortimer 167 A NEOGENE STRUCTURAL DOME IN THE KLAMATH MOUNTAINS, CALIFORNIA AND OREGON N. Mortimer and R.G. Coleman 179 STRATIGRAPHY AND SEDIMENTOLOGY OF THE PAYNE CLIFFS FORMATION, SOUTHWESTERN OREGON Brian K. McKnight 187 THE LOWER WESTERN CASCADE VOLCANIC GROUP IN NORTHERN CALIFORNIA Joseph A. Vance 195 CATASTROPHIC DEBRIS AVALANCHE FROM AN ANCESTRAL MOUNT SHASTA VOLCANO, CALIFORNIA .. D.R. Crandell, C.D. Miller, R.L. Christiansen, H.X. Glicken and C.G. Newhall 197 A GEOLOGIC CROSS SECTION OF NORTHEASTERN CALIFORNIA FROM SEISMIC REFRACTION RESULTS G.S. Fuis and J.J. Zucca 203 A POTENTIAL-FIELD INTERPRETATION OF THE STRUCTURAL EDGE OF THE CRETACEOUS HORNBROOK BASIN IN NORTHERN CALIFORNIA M.C. Erskine, Jr., J. A. Wolleben and D.L. Lawler 211 IMPLICATIONS OF PALEOMAGNETISM FOR THE TECTONIC HISTORY OF THE EASTERN KLAMATH AND RELATED TERRANES IN CALIFORNIA AND OREGON Edward A. Mankinen, William P. Irwin and C. Sherman Gromme 221 PALEOMAGNETIC CONSTRAINTS ON THE INTERPRETATION OF EARLY CENOZOIC PACIFIC NORTHWEST PALEOGEOGRAPHY RayE. Wells 231 A PALEOGEOGRAPHIC REINTERPRETATION OF SOME MIDDLE CRETACEOUS UNITS, NORTH-CENTRAL OREGON: EVIDENCE FOR A SUBMARINE TURBIDITE SYSTEM Lewis C. Kleinhans, Elizabeth A. Balcells-Baldwin and Richard E. Jones 239 INTRODUCTION TO FIELD TRIP Tor H. Nilsen U.S. Geological Survey 345 Middlefield Road Menlo Park, California 94025 GENERAL SETTING The Hornbrook Formation has attracted the attention of the petroleum industry for many years, The Upper Cretaceous Hornbrook Formation crops partly because natural gas has been found in out to the northwest of Mount Shasta in north- numerous water wells in the area. The potential for central California and southwestern Oregon (Fig. finding both petroleum source and reservoir rocks in 1). It forms a northwest-striking and northeast- the Hornbrook Formation to the east of the outcrop dipping homoclinal sequence that underlies a series belt, beneath the western Cascade Range, has of narrow, discontinuous, northwest-trending valleys resulted in the leasing of large areas, especially between highlands of the Klamath Mountains and the in the Modoc Plateau region (Alldredge and Meigs, Cascade Range (Fig. 2). The Hornbrook Formation 1984). An exploration well drilled by Klamath rests unconformably on highly deformed Paleozoic, Exploration in 1983-84 about 21 km northeast of Triassic, and Jurassic metamorphic rocks and on Yreka, on the south flank of Bogus Mountain (Fig. Triassic and Jurassic plutons of the Klamath 2), penetrated about 640 m of Cretaceous sedimentary Mountains. The Hornbrook is overlain unconformably rocks, with a show of wet oil or gas (Alldredge and to the northeast by lower Tertiary nonmarine Meigs, 1984). sedimentary and volcanic rocks of the western Cascade Range. The location of all relevant U.S. The Cretaceous Ochoco basin in the Mitchell Geological Survey quadrangles in southern Oregon and area of central Oregon (Fig. 1) has been an area of northern California is shown in Figure 3. active petroleum exploration because it contains more than 4,300 m of Cretaceous marine sedimentary The Hornbrook Formation is one of a large rocks. If the Hornbrook Formation, Ochoco basin, number of widely scattered Cretaceous sedimentary and Great Valley sequence originally formed part of units that crop out in various parts of Oregon and the same large depositional basin, and are possibly northern California (Fig. 1). These discontinuous interconnected today beneath the cover of volcanic remnants of Cretaceous strata crop out in the rocks, then a large petroleum province could Mitchell area and other parts of the Blue Mountains, potentially exist in southern Oregon and in the Grave Creek and O'Brien areas of the Klamath northeastern California, - and possibly farther north Mountains, on the northern and western flanks of the as well. Klamath Mountains in the Days
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