Friday, October 12, 2012

Part Five: Historic Oil Wells of the Little Spokane River Valley

(all rights to this material retained by author)

A Review of the Historic Oil Wells
of the Little Spokane River Valley
Regions Around
(part five)


Wally Lee Parker


… a sea of molten rock ...

            Over an eleven million year period — ending just six million years ago — an estimated forty-one thousand cubic miles of basalt flooded up from beneath the earth’s crust and then out and over sixty-three thousand square miles of what would eventually become the states of Washington, Oregon, and Idaho.  If collected into a single mass, this molten basalt would form a sphere just under forty-three miles in diameter.  If that sphere were allowed to empty out across the surface of Eastern Washington — meaning just that portion of the state to the east of the crest of the Cascade Mountains — it would cover the land just a hair’s breadth more than a mile deep in basaltic rock.  Poured out in hundreds and hundreds of separate molten extrusions, this incomprehensible deluge of lava has managed to obscure vast stretches of the older lands beneath a sizable portion of the three above noted states — much to the benefit of early 20th century oil speculators.
            But in all of this space, there is nothing rising significantly above the surface resembling a traditional volcano.
            One of the more insightful early scientific observations of the Pacific Northwest’s various outpours of molten rock occurred in 1879.  Scottish geologist Archibald Geikie (1835-1924) of the British Geological Survey had been invited by his North American scientific colleagues to tour the far western United States.  Writing in an engagingly non-technical style, Sir Geikie penned an article about this expedition which appeared in the October, 1881, issue of the British periodical Macmillan’s Magazine under the title “The Geysirs of Yellowstone.
Sir Archibald Geikie (1835-1924)
            Sir Geikie, with an unnamed travelling companion, rode the then ten year old transcontinental railroad from the eastern seaboard to Ogden, Utah, and from there traveled north by narrow-gage rail, stagecoach, and carriage to Fort Ellis near Bozeman, Montana.  At Fort Ellis Geikie presented a letter of introduction provided by “authorities at Washington” (probably agents of the United States Geological Survey), and “arranged to travel through the Yellowstone Park, as it is termed, and through the Mountains encircling the head-waters of the Snake River.”  In his story, Sir Geikie explained that Yellowstone Park was “that region of geysirs, mud volcanoes, hot springs and sinter-beds, which the United States Congress, with wise forethought, has set apart from settlement and reserved for the instruction of the people.”
            The military provided Sir Geikie and his companion with horses, mules, a guide, and a mule handler.  The four men packed through Yellowstone — visiting the geysers (or “geysirs,” as it was then spelled) — and then west over the “great divide” and down to a stream called “Henry’s Fork, one of the feeders of the Snake River.”  Following this steam through miles of forest, they eventually found themselves “picking” their “way across a dreary plain of sage brush on the edge of the great basalt flood of Idaho.”
            Sir Geikie’s “great basalt flood of Idaho,” at least the part he visited, isn’t part of the Columbia flood basalts.   Geikie’s flood basalt is actually part of the outpouring from Idaho’s much later great rift valley — though that was likely not evident to the geologists of the time.
            Near the conclusion of his story, Sir Geikie wrote, “The last section of our ride (his time in Idaho) proved to be in a geological sense one of the most interesting parts of the whole journey.  We found that the older trachytic lavas of the hills had been deeply trenched by lateral valleys, and that all these valleys had a floor of the black basalt that had been poured out as the last of the molten materials from the now extinct volcanoes.  There were no visible cones or vents from which these floods of basalt could have proceeded.  We rode for hours by the margin of a vast plain of basalt stretching southward and westward as far as the eye could reach.  It seemed as if the plain had been once a great lake or sea of molten rock which surged along the base of the hills, entering every valley, and leaving there a solid floor of bare black stone.  We camped on this basalt plain near some springs of clear cold water which rise close to its edge.  Wandering over the bare hummocks of rock, on many of which not a vestige of vegetation had yet taken root, I realized with vividness the truth of an assertion made first by Richthofen (most likely referring to Ferdinand van Richthofen, German geologist, 1833-1905), but very generally neglected by geologists, that our modern volcanoes, such as Vesuvius or Etna, present us with by no means the grandest type of volcanic action, but rather belong to a time of failing activity.  There have been periods of tremendous volcanic energy, when, instead of escaping from a local vent, like a Vesuvian cone, the lava has found its way to the surface by innumerable fissures opened for it in the solid crust of the globe over thousands of square miles.”
            Although Geikie was walking on relatively recent flows — most likely millions of years younger than the last of the Columbia basalts — the eruptive mechanisms that eventually filled the eastern reach of southern Idaho’s Snake River Plain often mirror — though not exclusively — those of the Columbia flows.  In that regard Geikie’s statement “Bare hummocks of rock, on many of which not a vestige of vegetation had yet taken root” could very well describe the floor of the Little Spokane River Valley in those years after the great basaltic tides of Columbia lavas had flooded in from the south, but before the subsequent millions of years of erosion, sedimentation, and glacial disruption had turned the valley’s floor fertile once again.
            In 1892 Professor Edward Hull (1829-1917) of the Royal College of Science, Dublin, in his book Volcanos: Past and Present, wrote of the actual Columbia flows, “The absence, or rarity, of volcanic craters … in the neighborhood of these great sheets has led American geologist to the conclusion that the lavas were in many cases extruded from fissures in the earth’s crust rather than from ordinary craters.”
            As for the American viewpoint, in 1897 geologist Israel Cook Russell (1852-1906) penned a dramatic description of the Columbia basalt floods for the abstract of his U. S. Geological Survey paper, Principle Features of the Geology of South Eastern Washington.
            “The Columbia lava flowed about the bases of the mountains of Eastern Washington and the adjacent portion of Idaho in a series of inundations which covered the low country to the south.  The level basaltic plateau meets the mountains … in much the same manner that the sea forms a rugged and deeply indented coast.  The lava entered the valleys and gave them level floors of basalt; the deeply sculptured ridges between the valleys were transformed into capes and headlands; outstanding mountain peaks became islands in the sea of molten rock.”
            Evidence of this basalt infilling can be found both on the surface and below the surface of the Little Spokane River Valley, where at least several of these massive floods poured north over the present day site of Spokane to form molten lakes between the low, rounded mountains rising east, west and north of the valley.  Remnants of these floods suggest the last invading flow reached more than a hundred feet above the present day level of the little town of Clayton.
            Israel Russell also stated, “The great fissure eruptions which supplied the Columbia lava, as the basalt is termed, occurred in the Miocene,” — suggesting that the geologic community had early on assumed as solved both the manner of upwelling and general age of these ancient flows.  And the United States Geological Survey concurs that the Columbia Plateau basalts were formed by over three hundred separate outpours occurring periodically between seventeen and six million years ago — within what geologist recognize as the Miocene epoch.
            Using laboratory and computer modeling, as well as extensive field studies, geologists have been able to visualize just how magnificent and terrifying one of these molten floods would have been.  Accompanied by ongoing tremors as the older lands around these monstrous clusters of fissures settled downward to replace the extruding magma, these floods of highly viscous lava are calculated to have poured across the surface at an average speed of perhaps five miles an hour.  Although that doesn’t sound impressive, if the pace was steady the flood’s front could travel 120 miles every 24 hours.  Even the fastest earthbound animals, all made of fatigable flesh, couldn’t escape that — as the hollow casts of various Miocene era creatures entombed by the lava clearly shows.
            But how could lava have continued to flow hundreds of miles from the point it squeezed out of the earth’s surface?  Evidence suggests that the leading edge of the flood could easily have been a hundred feet high.  The relatively cold crust forming above the flow would have acted as insulation, keeping the lava flowing underneath super-hot (as can be observed today with much smaller lava flows).  Just like the flow’s upper surface, the leading edge would have continually tried to form a solid skin as it — being exposed to the air — cooled.  And the blistering lava behind the blackening leading edge would have continually broken through the crust, billowing forward in luminous tongues, stuttering in the direction of least resistance.
            Finding obstructions such as highlands, mountain peaks, or canyon walls, the flow’s forward momentum would still into lakes of lava.  From there it would gather higher and higher, until it overflowed the obstacle, found a way around, or began flowing in a new direction.  When the outpour finally stopped, it might take several years for the congealed flood to fully cool.
            The new surface left behind would not be smooth.  Though relatively level, this ragged plane of cooling basalt would prove a vast field of lifeless stone, broken into jagged razors of rubble.  It would be strewn with cracks, pits, and mounds, making movement across these newly formed beds difficult in the extreme.  And then, through passing ages of cycling sun and snow, rain and wind, physical and chemical erosion would tear the rocks apart, crumbling the surface into soil.  Streams and rivers would cut canyons.  Ponds and lakes would form.  A few thousand years, or even hundreds of thousands of years would pass between eruptions.  If the quiet was long enough, the jagged terrain might even erode into gently rolling grassland.  But eventually the floods of blistering rock would return, covering everything, and the process would begin again.
            As for the forces driving the uplifts that cracked the earth’s surface into swarms of volcanic vents —into swarms of crustal rips that slowly moved north along the Oregon/Idaho border and into the southeastern tip of Washington State — the root of that story begins approximately 750 million years ago in the interior of the supercontinent of Rodinia.
            Current tectonic theory suggests that the earth’s continental plates — massive, eggshell like fragments of solidified crust — are in constant motion, colliding and ripping apart as they slide over the viscous magma of the planet’s molten mantel.  Geologic hypothesis speculates that the process of supercontinent formation of which Rodinia is a part began about 3½ billion years ago — not long (geologically speaking) after the earth’s condensation from the solar system’s primordial cloud — and that four or five previous supercontinents had existed and broken up in turn before the Rodinia supercontinent came together.  In general, as these supercontinents break apart, the fractures first become visible as rift valleys.  These spreading valleys eventually become inland seas, and then — as these fractured lands drift apart (or more apply are pushed apart by upwelling currents of superhot magma rising out of the earth’s deep interior) — the seas between become oceans.
            750 million years ago the Pacific Northwest segment of what would eventually become the North American continent was wedged within the interior of the above noted supercontinent of Rodinia.  For some time the part of the supercontinent that would eventually support the towns of Spokane, Deer Park, and Clayton was likely an inland flood plain, sequentially covered by in-washes of muddy sediments.  The evidence for this is found at an outcropping of some of the oldest rock so far discovered in the State of Washington — an ancient deposit on Prosser Hill just southeast of the small town of Four Lakes in western Spokane County.  Described as a meta-sedimentary stone showing mud cracks and ripple marks consistent with deposits forming in shallow lakes or along slow moving riverbeds — both subject to periodic drying — this road cut exposure of crumbling slate-like rock is located at — approximately — the 2,500 foot level on the northeastern slope of the hill.  Geologists have dated this mudstone to the middle Proterozoic — 1 billion, 200 million years ago.
Prosser Hill Mud Stone
(photo by author)
            According to current thinking — and in relation to the present day Pacific Northwest — the rift fracturing the crustal plate of Rodinia in the late Proterozoic Eon would have trended in a north/south direction several dozen miles west of the towns of Spokane, Deer Park, and Clayton.  This would have left the future site of these towns teetering on the very edge of the new North American continental plate.  Forming part of the continental shelf, it’s probable that this area would have subsided below the newly forming Pacific Ocean as the opposite side of the rift was pushed away, and ongoing volcanic extrusions formed a new ocean bottom in its place.  The actual beaches of North America’s new coast would have likely surfaced out of the primal ocean some distance to the east of this opening rift — suggesting that the town of Deer Park would have never been prime ocean front property.
            As the Pacific Northwest’s former self slowly drifted away to drop over the earth’s curvature — drifted away to eventually becoming part of present day China — the leading edge of the new North American plate entered a long period of geologic quiescence.  Geologically speaking, the Pacific Northwest became a coastal backwater.
By 300 million years ago the other side (currently the eastern side) of the North American plate had welded itself into Pangaea, the next supercontinent to form.  Pangaea held together for another 100 million years.  Then, as a massive complex of rifts began separating the North and South American continental plates from Asia, Europe, and Africa some 200 million years ago, Pangaea in turn began to rip apart — the complex of dividing cracks eventually becoming the Atlantic Ocean.
            Even today the Atlantic Ocean continues to expand, and new crustal materials are volcanically extruded along what is now called the mid-Atlantic ridge.  Current hypothesis suggests that it’s a set of massive thermal currents rising from deep in the earth that are pushing the North American plate in a westward trending direction — essentially pushing the North American plate across the Pacific in pursuit of its former self.  Due to this “new” planetary paradigm of some 200 million years ago — as the North American tectonic plate began to move, began to drift over the earth’s surface — the Pacific Northwest’s period of geologic quiescence ended.
            In the wake of the Pacific Northwest’s long separated “Chinese” part, the forces of plate tectonics (continental drift) left a litter of newly formed plates on the ocean’s floor and towering volcanic islands resting on those plates.  As the American continent began scooting westward across the Pacific at an average of two inches a year, it began colliding with this newly extruded material.  In general the floor of the Pacific basin is being pushed down and under the overriding mass of the North American plate — though at times portions of the plates being overridden and the volcanic islands riding on top of those plates have been scrapped off the down and under moving plates.  These scraped lands then collide and weld into the oncoming mass of the North American continent.  As a result, the coastline of the Pacific Northwest continues to expand to the west as new lands are melded onto the coast.  In the last 200 million years this process has added over 300 miles of new continental land to what was once the leading edge of the Rodinia rift.
            One of the side effects of pieces of the former Pacific Basin plunging beneath the overriding North American plate is the generation of tremendous amounts of frictional heat.  This massive heat melts the subducting rock — the down-diving rock — leaving vast pools of magma relatively close to the earth’s surface.  All the while the North American plate continues its slow westward migration over the top of these newly formed hotspots.  It’s believed these subduction induced hotspots melting their way upward through the earth’s crust are the primary cause of volcanism throughout the Pacific Northwest — including the volcanism that forced the molten Columbia basalts through cracks in the earth’s surface.  It’s also believed that these subduction induced hotspots are the reason for the cracks.
            When thinking of rock as a fluid, the same general principles apply as to any other fluid.  Heat stored within a fluid tends to migrate into the walls of the containing vessel.  If that containing vessel is rock, the containing rock will warm.  If the fluid being contained is hot enough, the amount of heat moving into the containing rock will melt it — turning it into molten magma as well.  Since warmer fluid rises and colder fluid sinks, the newly melted and generally cooler lava at the top of the containment vessel will tend to sink and be replaced by hotter lava from beneath.  Due to the natural bias of heated materials to rise, this hotter lava will continue melting its way upward through the once solid rock.
This simple principle of heat migration outlines how vast pools of magma can rise to the surface through an overburden of solid crust.  As the pools approach the thinning surface they often bulge the still solid crust upward.  Stress cracks — rips — tend to form as a result of the increasing surface area of these stressed, dome-like bulges.  And these surface rips are the areas of weakness through which the upward-pressing molten rock can find a pathway to the surface.
This is believed to be the basic geologic mechanics that allowed the Columbia basalts to repeatedly flood across the states of Oregon, Washington, and Idaho.
            Evidence of Israel Russell’s “great fissure eruptions” is found in the form of what geologist call dikes.  A dike is the infilling within a cleft opened within pre-existing rock.  When crustal fissures ripped through the existing rock surface and the lava being pushed up and out of these fissures eventually stopped, what remained within the fissure would cool and solidify.  Chemical, magnetic, and visual differences between the original surface rock and the infilling rock of the dike can reveal the fissure and therefore the site of eruption.  In some instances the melt-edges of the original rock through which these lavas have pushed prove more resistant to erosion than the outpoured lava, allowing the vent dikes to stand out in relief as the lavas around them erode away.  These dikes are usually no more than a dozen feet wide, though miles in length.  And the fissures tend to cluster in swarms — the swarms covering areas a mile or two wide and 30 to 120 miles long.  With some variation, these vents tend to align themselves in a roughly north/south direction — suggesting they are following the primordial subduction fault lines originally traced along North America’s archaic coast.
            As far as chemical traces and exact percentages of mineral ratios are concerned, volcanic materials erupted from different sites are never exactly alike.  These minute differences can act as fingerprints — allowing specific lavas to be grouped together as to source.  When visible, source dykes can be identify by analyzing — by fingerprinting — the materials frozen in their throats.  A large number of the Columbia basalts have been mapped by tracing these unique chemical signatures across hundreds of miles of flows.  Though much work is yet to be done, each year the picture becomes a little clearer.  But through it all, the discoveries made since Archibald Geikie, Professor Hull, and Israel Russell’s day have done little to alter these men’s original descriptions of the Pacific Northwest flood basalts.  Once these outpours truly were a sea of molten rock.
            Geologists have also determined that the Selkirk Mountain Range once continued hundreds of miles to the south of present day Mount Spokane.  Other than a few isolated peaks, most of these mountains have disappeared — have sunk as the vast pools of lava beneath emptied out onto the surface and the original surface sank, taking the mountains with them.  Steptoe Butte, approximately 40 miles south of Spokane, is the top of one such sunken mountain.
            As for what the original land was like — the lands now buried with the southern reach of the Selkirk Mountains — some clues can be gained from looking to the land both north and south of the Columbia Plateau.  Otherwise — and especially in the early 20th century — most anything could be imagined beneath this basaltic overburden.  And the Inland Empire’s early oil prospectors seemed to imagine whatever might prove most profitable.

… to be continued …


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