Oregon produces some of the best gemquality feldspar in the world. The book concludes with an illustrated identification guide to the blue ridge mountains many rocks, minerals, trees, plants, flowers, and birds. Geological studies in the klamath mountains province. Visit tropical islands sequestered in the wallowa mountains, ancient volcanoes in the depths of hells canyon, and cascade valleys carved by glaciers towering far above your head. Historically, most of the mapping in the blue mountains has been along the western margin.
Geologic mapping in the klamath mountains is difficult due to the ruggedness of the terrain and limited access. Theres gold in oregon, and this book will help you find it. Covering the largest area of the blue mountains is the sprawling butte lands of the ochoco mountains. A bibliography of klamath mountains geology, california. Oregon historical society geology related records publications oregon dma, dmea, ome dockets the mineral resources of oregon periodical published by the oregon bureau of mines and geology, 19141923 last updated 03302020 about the publications center, paper maps, and printing maps. New evidence, based on mineral dating, suggests that rocks of the blue mountains, the oldest geological formation in oregon, may have been derived from. Ore bin oregon geology magazine journal oregon department.
Back then, the implications of plate tectonic theory were only beginning to shape geologic research and discussion. They are not the tallest mountains in the west, nor probably the prettiest, but for many people living in northeastern oregon and southeastern washington, the blue mountains are cherished as. Guide to the geology and natural history of the blue ridge. Smith published a paper 16 on the stratigraphy and structure of steens and pueblo mountains, chiefly for the purpose of advancing a compressional interpretation of the origin of the former. Carbonate reefs formed in the shallow seas of that time that have now been transformed. The geology of the pacific northwest includes the composition including rock, minerals, and soils, structure, physical properties and the processes that shape the pacific northwest region of north america. Vallier 1995 petrology of pretertiary igneous rocks in the blue mountains region of oregon, idaho, and washington. The range has an area of about 15,000 square miles 38,850 km 2, stretching east and southeast of pendleton, oregon, to the snake river along the oregonidaho border. The blue mountains cover eight counties across two states. Although the beautiful blue mountains, ranging along to the west of the baker city area up and over i84 into the southeast corner of washington, offer an abundance of outdoor recreation opportunities, from hikes and horseback rides to soaks at lehman hot springs and snowy slope action at anthony lakes mountain resort, they are also notable as what many oregon trail emigrants called the most. Slightly less than a sixth of oregon s land area, the region occupies about 15,000 square miles.
Located between the aldrich mountains and central oregon, the ochocos vary from the taller mountains such as lookout mountain in the west, to the john day fossil beds and sutton. The range reaches a width of 68 mi and an average elevation of about 6,500 ft 2,000 m. Slightly less than a sixth of oregons land area, the region occupies about 15,000 square miles. Hornblende and biotite quartz diorite tonalite, trondhjemite, granodiorite, and small amounts of norite, in batholithic masses and large dikelike bodies. Published since 1911, it is produced by the oregon state archives, a division of the secretary of states office. An historical gazetteer of the useful, the curious. Book celebrates blue mountains of the pacific northwest. The blue mountains, stretching south of walla walla into central oregon, are.
The wallowa terrane is one of five precenozoic terranes in the blue mountains province of oregon, idaho, and washington. Geology of the wallowa terrane, blue mountains province, in the. I wrote this book because i wanted to tell this story as a sort of biography. Natural history of the blue mountains of northeastern oregon and.
Its late triassic history is considered here by examining the two most. It is the site of an astronomical observatory called the pine mountain observatory. The landforms of oregon are so varied and complex in origin that the authors have divided the book into a series of chapters each addressing a particular geologic province topographic expression. The book includes biographical sketches of notable geologists. For those seeking a greater understanding of the inner workings of the geology and natural history of the blue ridge, this is an indispensable companion.
Oregon geology by elizabeth and william orr is the real deal a geologic reference written for and by geologists. This guide explores the paleozoic and mesozoic geology of the wallowa terrane as exposed in northern hells canyon of idaho, oregon, and washington figs. The blue mountains are a mountain range in the western united states, located largely in northeastern oregon and stretching into southeastern washington. Stops and particular geologic features are measured in river miles above the confluence of the snake and columbia rivers. Geologic map of the klamath mountains, california and oregon. The terranes of the blue mountains formed in and around an ancient subduction zone. The name oregon sunstone is used for gemquality feldspars from oregon, with and without aventurescence.
The blue mountains indeed look blue from a distance, a formidable range rising to more than 9,000 feet2,743 meters and stretching from the columbia river southeast to the snake river. Baker city, oregon with the blue mountains in the background, seen from the national historic oregon. Rivers slowly cut deep gorges through the sandstone, coal shale and lava rock layers, gradually washing away immense volumes of rock shown in brown on above diagram and producing the blue mountains landscape of today. The blue mountains province is located in the southeast corner of the state, south of the snake river. Includes bald mountain tonalite and anthony lake granodiorite of taubeneck 1957, tonalite and trondhjemite of wallowa batholith and cornucopia stock taubeneck, 1964. Geology of lode gold districts in the klamath mountains, california and oregon by preston e. Geology of the blue mountains region of oregon, idaho, and washington u. Klamath mountains, segment of the pacific mountain systemof western north america.
A bibliography of klamath mountains geology, california and oregon, listing authors from aalto to zucca for the years 1849 to mid2003 compiled by william p. Field trip guide to the upper cretaceous hornbrook. Insights from springdominated streams in the oregon cascades dorsey. When the first edition of roadside geology of oregon was published in 1978, it was revolutionary the first book in a series designed to educate, inspire, and wow nongeologists. Blue mountains geology 308 with miles at university of. The subranges of the blue mountains were once an arc of volcanic islands thousands of miles south and further west in a giant ocean called panthalassa. Geomorphic and hydraulic effects of large woody debris. A harrowing obstacle for oregon trail pioneers, today this route up into the blues is pure delight, winding past rolling ranchlands, rocky peaks, wild rivers and. Amer basalt basin and range block blue mountains butte caldera california canyon cascade range cave cenozoic central oregon coast range coastal columbia river basalts cones continental county crater creek cretaceous crust crustal deposits deschutes east eastern oregon eocene erosion eruptions extends fault feet formation fossils geology geology. A comprehensive treatment of the states geologic history, oregon geology moves through oregons regions to closely examine the unique geologic features of each, from the blue mountains to the willamette valley, from the high lava plains to the coast range. Hotz the klamath mountains geologic province, in northwestern california and southwestern oregon, is divisible into four northtrending concentric arcuate lithologic belts which are convex to the west. Natural history of the blue mountains of northeastern.
Geologists hadn t yet learned that oregon s klamath and blue mountains were pieces of fartraveled. The metamorphic petrology and structural geology of the serpentinite. Mineral ages show blue mountain rocks related to klamath. Each belt contains several smaller terranes that came together prior to accretion to north america. Tectonic map of the klamath mountains of california and oregon the klamath mountains contain at least four belts of accreted terranes, separated from each other by eastdipping thrust faults. Blue mountains, range curving northeastward for 190 mi 310 km from central oregon to southeastern washington, u.
Geology of the wallowa terrane, blue mountains province. Its correlation with the northwestern boundaries of the klamath and blue mountain provinces suggests that these are continuous beneath the cascade volcanic. The oregon trail and modernday interstate 84 wind and meander through the blue mountains in ne oregon. Pine mountain is a rhyolitic mountain east of bend and south of u. Bibliography of the geology and mineral resources of oregon eighth supplement, 19801984 introduction the original bibliography of the geology and mineral resources of oregon was compiled by r. Stratigraphic and sedimentological analysis of sedimentary sequences from the wallowa terrane of northeastern oregon has provided a unique insight into the paleogeography and depositional history of the terrane, as well as establishing important constraints on its tectonic evolution and accretionary history. The oldest rocks in the blue mountains comprising the regions basement, are faulted, folded, intruded and lightly metamorphosed rocks formed mainly from marine sediments deposited 470330 million years ago m. The rocks and volcanoes were rafted toward the continental margin on a moving tectonic plate, and eventually accreted to the continental margin.
Within the rain shadow of the cascade range, its arid climate supports a unique ecosystem that differs greatly from mountain ranges to the west. Route 20 us 20 in eastern deschutes county, oregon, united states. Oregons rose city is both green, as in ecoconscious, and green, as in lush, a river edged port city thats also a laidback multicultural urban center with forest and. Geology of lode gold districts in the klamath mountains. The majority of the blue mountains lie within oregon. Smith points out that a similar theory 17 had been previously propounded to explain the structure of apparently analogous features in. The range extends southward for about 250 miles 400 km from the foothills south of the willamette valley in southwestern oregon, u. Oregon department of geology and mineral industries. The main downsides were that it was a little hard to pinpoint specific areas, as it covered fixed routes, and there were some that werent addressed. Regional gravity data clearly show a zone of southwestnortheast lineations across oregon that defines a major crustal lineament. Ironside mountain 7811 ft monument rock wilderness peaks 7879 ft castle rock 6837 ft. They can be found in colors that range from clear through yellow, orange, pink, red, green, and blue.
Geology, minerals, energy, and geophysics science center description map. Geology of the blue mountains region of oregon, idaho, and. Klamath mountains mountains, united states britannica. The oregon blue book is the official state fact book about all levels of government in oregon. Irwin openfile report 03306 supersedes openfile report 95558 2003 u. Blue mountains mountains, oregonwashington, united. Finally the blue mountains were pushed up and the coastal sediments sagged, creating the eastern escarpment of the blue mountains. Dissertations and theses department of earth sciences. This book focuses on the stratigraphy, ages, structure, and chemical characteristics of terrestrial cenozoic volcanic and. The blue mountains, perhaps the most geologically diverse part of oregon, consist of a series of mountain ranges, rolling uplands, and valleys in the northeastern part of the state and extending into southeastern washington.
The mountains rise to mount eddy 9,038 feet 2,755 m west of mount shasta in california and include numerous. The blue mountains are a mountain range in the western united states, located largely in. Oregon geologists have mapped the blue mountains and klamaths with painstaking. Its existence is supported by geologic and geophysical data. The mountain is a part of the deschutes formation which is related to cascade volcanism and is the southeasternmost exposure of the formation and is of similar age to cline. We recently went on a geologyheavy trip around oregon, and this book proved to be a fantastic reference for the most part.
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