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The Spokane Flood Controversy VICTOR R

The Spokane Flood Controversy VICTOR R

Chapter 1 The Spokane Flood Controversy VICTOR R. BAKER Department of Geological Sciences The University of Texas at Austin Austin, Texas 78712

ABSTRACT carved into mazes of bultes and . Everybody on the plateau knows scabland. It The Spokane Flood controversy is both a story interrupts (he wheat lands, parceling them out into hill tracts less than 40 acres to more than of ironies and a marvelous exposition of the 40 square miles in extent. One can neither scientific method. In a brilliant series of papers reach them nor depart from them without cross- between 1923 and 1932, shocked ing some part of the ramifying scabland. Aside the geological community with his studies of an from affording a scanty pasturage, scabland is enormous plexus of proglacial channels eroded almost without value. The popular name is an expressive metaphor. The scablands are wounds into the loess and basalt of the , only partially healed—great wounds in the epi- eastern . This region, which he named dermis of soil with which Nature protects the the "Channeled Scabland," contained erosional underlying rock. and depositional features that were unique among With eyes only a few feet above the ground fluvial phenomena. With painstaking field work, the observer today must travel back and forth repeatedly and must record his observations before the advent of aeriaj photographs and mentally, photographically, by sketch and by modern topograhic maps, Bretz documented the map before he can form anything approaching field relationships of the region. He argued that a complete picture. Yet long before the paper the landforms could only be explained as the bearing these words has yellowed, the average product of a relatively brief, but enormous flood, observer, looking down from the air as he crosses the region, will see almost at a glance which he called the "Spokane Flood." Consider- the picture here drawn by piecing together (he ing the nature and vehemence of the opposition ground-level observations of months of work. to this outrageous hypothesis, the eventual tri- The region is unique: let the observer take the umph of that idea constitutes one of the most wings of the morning to the uttermost parts of fascinating episodes in the history of modern the earth: he will nowhere find its likeness. Conceive of a roughly rectangular area of . about 12,000 square miles, which has been tilted up along its northern side and eastern end to produce a regional slope approximately 20 feet (o the mile. Consider this slope as the INTRODUCTION warped surface of a thick, resistant formation, over which lies a cover of unconsolidated ma- The inimitable words of J Harlen Bretz (1928c, terials a few feet to 250 feet thick. A slightly p. 446) describes the scene in eastern Wash- irregular dendritic drainage pattern in maturity ington: has been developed in the weaker materials, but only the major stream ways have been eroded "No one with an eye for landforms can cross into the resistant underlying bed rock. Deep eastern Washington in daylight without en- canyons bound the rectangle on the north, west, countering and being impressed by the "scab- and south, the two master streams which oc- land". Like great scars marring the otherwise cupy them converging and joining near the fair face of the plateau are these elongated southwestern corner where the downwarping of tracts of bare, or nearly bare, black rock the region is greatest. Conceive now thai this drainage system of pounded of river-bottom modifications of the the gently tilled region is entered by glacial invaded and over-swept drainage network of waters along more than a hundred miles of its hills and valleys. Hundreds of cataract ledges, northern high border. The volume of the in- of basins and canyons eroded into bed rock, of vading water much exceeds the capacity of the isolated buttes of the bed rock, of gravel bars existing stream ways. The valleys entered be- piled high above valley floors, and of island come river channels, they brim over into neigh- hills of the weaker overlying formations are boring ones, and minor divides within the sys- left at Ihe cessation of this episode. No fluvia- tem are crossed in hundreds of places. Many of tile plains are formed, no lacustrine flats are these divides are trenched to the level of the deposited, almost no debris is brought into the preexisting valley floors, others have the weaker region with the invading waters. Everywhere superjacent formations entirely swept off for Ihe record is of extraordinarily vigorous sub- many miles. All told, 2800 square miles of the fluvial action. The physiographic expression of region are scoured clean onto the basalt bed- the region is without parallel; it is unique, this rock, and 900 square miles are buried in the channeled scabland of the Columbia Plateau." debris deposited by these great rivers. The topographic features produced during this epi- A mere glance at a modern LANDS AT sode are wholly river-bottom forms or are com- photograph of the Channeled Scabland (Fig. 1.1)

Figure 1.1. LANDSAT photograph of the northern photograph. The far left scabland complex is the Grand part of the Channeled Scabland. Scabland channels form -Harlline Basin-Lenore tract. At the the dark-toned anastomosis that contrasts with the wheat center is Ihe Telford-Crab Creek Scabland complex. At farms on the light-toned loess. The Columbia the right (east) is the Cheney-Palouse scabland tract and Spokane Rivers occur at the top (north) of the (LANDSAT E-1003-18150 composite, 26 July 1972).

OPTQINAL OP POOR will show the features that Bretz, studying from Dr. O. E. Meinzer, the eminent hydrologist the ground, developed as the basis of his flood of the U.S. Geological Survey, took an early hypothesis. The extensive wheat cultivation on interest in the western part of the Channeled the loess presents a vivid contrast to the flood- Scabland. He observed (Meinzer, 1918) that the scared basalt exposed in the channel ways. glacially diverted Columbia at Grand Coulee "cut The unique character of the dry river courses precipitous gorges several hundred feet deep, de- ("") of the Channeled Scabland was ap- veloped three cataracts, at least one of which was preciated by the first scientific observers of the higher than Niagara, . . . and performed an al- region. Rev. Samuel Parker (1838) provided the most incredible amount of work in carrying first published statement on the Grand Coulee: boulders many miles and gouging out holes as "{it] was indubitably the former channel of the much as two hundred feet deep." He implies that river [Columbia]." Lieutenant T. W. Symons the great occurred because the Columbia (1882) of the U.S. Army traversed the Grand River was diverted across the steeply dipping Coulee, stating that he, "went north through basalt surface of the northern Columbia Plateau. the coulee, its perpendicular walls forming a vista It was not until the studies of J Harlcn Bretz like some grand old ruined roofless hall, down (1923-1932) that the scientific study of this re- which we traveled hour after hour." Symons gion began in earnest. Bretz interpreted the ero- (1882) initialed the widely held notion that dur- sional and depositional features of the region as ing glacial episodes of the the Colum- the product of a brief but enormous flood, which bia had simply been diverted across the Colum- he called the Spokane Flood. For in the bia Plateau. Variations on this general theme 1920's this was clearly an outrageous hypothesis. were standard in the early literature (Russell, Olson (1969) has described the reception of the 1893; Dawson, 1898; Salisbury, 1901; Calkins, idea. "During its not always calm history, the 1905). story of the development of the Channeled Scab- The Grand Coulee gained international fame land was thought by some to have brushed be- in 1912 when it was traversed by the American yond the dividing line in flaunting catastrophe too Geographical Society's Transcontinental Excur- vividly in the face of the uniformity that had sion. Karl Oestreich (1915) of the University of lent scientific dignity to interpretation of the his- Utrecht described the coulee as "eines machtigen tory of the earth." The reaction of the scientific Flusses Belt . . . ohne jede Spur von Zerfall der community was predictable, "this heresy must frischen Form." He provided an excellent de- be gently but firmly stamped out" (Bretz and scription of significant features that required a others, 1956, p. 961). special origin: exhumed granite hills, perpendic- ular walls, and the hanging valleys marginal to the upper Coulee. He ascribed these hanging AN OUTRAGEOUS HYPOTHESIS valleys to glacial erosion and to deepening of the coulee by the glacial Columbia River. Moreover, Because the Spokane Flood controversy is so he recognized that the upper Grand Coulee was tied to Bretz as its central figure, this review will carved through a preglacial divide, which he cor- consider part of his professional career during rectly located just north of Coulee City. the years of his formulation of the flood hypothe- Another foreign observer on the American sis. The ensuing debates were not always marked Geographical Society excursion was H. Baulig, by scientific objectivity, but their recounting is a University of Rennes. Baulig (1913) described fascinating example of the triumph of an out- the loess, coulees, dry falls ("cataracte desseche~e rageous hypothesis. Only in the last two decades de la Columbia"), rock basins, and plunge pools. has the flood hypothesis gained general ac- The origin of these features was ascribed to a ceptance. It is a measure of scientific maturity glacial diversion of the Columbia. Nevertheless, that in current studies of the Channeled Scabland, he marveled at the scale of erosion (Baulig, "the idea, but not the man has become central" 1913, p. 159): "peutetre unique du relief ter- (Olson, 1969). restre,—unique par ses dimensions, sinon par son While teaching at the , origine." Bretz began conducting a summer field course in the wilds of the Columbia Gorge between the scabland gravels were organized into terrace Washington and Oregon. The idea for a study of remnants. However, after noting that they lacked the Channeled Scabland came during the summer a "sharp terrace form," this interpretation was of 1922. As he relates the story, "One summer quickly modified (Bretz, 1923b, p. 643): ". . . I was out in Spokane. I saw -a section of a topo- the evidence seems conclusive that all gravel de- graphic map of what is now called the Channeled posits of the scablands are bars, built in favorable Scabland, and from that I got the idea" (Quota- situations in the great streams which eroded the tion from Times, Sunday Magazine, July channels." With this conclusion he was forced to 11, 1971, p. 13). call upon catastrophic quantities of water. If the Without the benefit of modern aerial photo- bars were over 100 feet in height, even greater graphs or even adequate topographic map cov- water depths were required to form them. The erage, Bretz began to take parties of advanced second paper (Bretz, 1923b) also included the students into the region for month-long field first detailed geomorphic map of the entire studies. The work continued over the next 7 Channeled Scabland, showing the overall anas- years. He soon revised an earlier notion that a tomosing pattern assumed by a great flood of marine submergence had occurred just down- water. stream from the Channeled Scabland (Bretz, Bretz (1923b, p. 624-626) was the first to 1919). Nevertheless, the erratic granite boulders, recognize the streamlined loess hills of the which he had used as evidence for the submerg- Cheney-Pafouse scabland. He described them as ence, were scattered about the basalt plateau far follows: "A very striking and significant feature beyond the limits reached by Pleistocene glacia- of the steepened slopes is their convergence at the tion. Bretz (1923a) named the glaciation re- northern ends of the groups to form great prows, sponsible for these erratics the "Spokane Glacia- pointing up the scabland's gradient. . . . The nose tion." of a prow may extend as a sharp ridge from the Although his first paper on the Channeled scablund to the very summit of the hill. Il is im- Scabland (actually the text of an oral presenta- possible to study these prow-pointed locssiul hills, tion to the Geological Society of America) took surrounded by the scarred and channeled basalt care not to call upon cataclysmic origins, Bretz scablands, without seeing in them the result of (I923a) provided a detailed description of a powerful eroding agent which attacked them physiographic relationships in the region. An about their bases and most effectively from the example in his description (Bretz, 1923a, p. 601) scabland's up-gradient direction." of the pre-flood drainage line that was Inter en- Brelz knew that his interpretation would be larged to form the lower part of Moses Coulee: controversial. He argued (Brelz, 1923b, p. 621), "The cliffs here are deeply notched by wide-open "All other hypotheses meet fatal objections. Yet V-shaped tributary valleys. . . . These notches the reader of the following more detailed de- give the cliffs a striking resemblance to a series scriptions, if now accepting the writer's interpre- of great rounded gables in alignment. . . . Both tation, is likely to pause repeatedly and question widening and deepening in the basalt occurred that interpretation. The magnitude of the erosive and the tributaries were left hanging. They have changes wrought by these glacial streams is noth- since attained topograhpic adjustment by build- ing short of amazing." ing large alluvial fans out on the canyon floor." Bretz subsequently argued that the rugged He further noted that prodigious quantities of scabland of anastomosing channels and rock water were involved in the erosion. Referring to basins cut into the basalt was the product of sub- three outlets at the south end of the Hartline fluvial quarrying. He described this process for Basin (Dry Coulee, Lenore Canyon, and Long the modern Columbia River near The Dalles, Lake Canyon), Bretz (1923a, p. 593-594) Oregon (Bretz, 1924). Moreover, he asserted states, ". . . these are truly distributary canyons. that only large vigorous streams could produce They mark a distributive or braided course of the such forms. The eventual conclusion from these Spokane glacial flood over a basalt surface which varying lines of evidence was that so much glacial possessed no adequate pre-Spokane valleys." meltwater occupied the pre-existing valleys on the Bretz (1923a, p. 603) originally thought that Columbia Plateau that it must have constituted a vast but short-lived flood, the "Spokane flood" burst produced by volcanic activity beneath an (Bretz, 1925, p. 98). The flood spilled across . He noted severe objections to either hy- pre- divides, eroding the maturely pothesis, but held that the great flood had oc- dissected loess topography to form linear chan- curred in spite of the problems in accounting for nels, nnd leaving a legacy of scoured loess scarps, its source. hanging distributary valleys, and high-level fluvial deposits. It also built the huge constructional bars of gravel and then subsided so quickly that these bedforms were left almost unmodified by the sub- THE SPOKANE FLOOD DEBATE siding water (Bretz, 1925, p. 105). Bretz (1925) was able to trace the path of In 1927 the Geological Society of Washington, the great flood downstream through the Columbia D.C., invited Bretz to give a lecture "Channeled Gorge to its debouchure into the Willamette low- Scabland and the Spokane Flood." It was a pur- land, where it built the "Portland delta." On poseful invitation: a veritable phalanx of doubters this great subfluvial fan he recognized the signif- had been assembled to debate the flood hypo- icance of macroturbulence in accounting for thesis. Bretz (1927a) presented the basic out- certain flood features: "The Rocky Butte fosse is line of his theory to date, citing the detailed field but the unfilled locus of an eddy caused by evidence which he could not explain by any hy- downward deflection where the current impinged pothesis other than a great flood of water. The on the east face of the butte. . . . The dependent first discussant was W. C. Alden, who cautiously terrace to the west was deposited in the slack warned of the difficulties with the hypothesis. water below the obstruction" (Bretz, 1925, p. Lacking personal field experience in the region 256). he suggested that the rock basins might be col- Bretz (1925) even made the first estimate of lapsed lava caves, but he realized that the major the flood discharge. He chose Wallula Gap for features indicated stream erosion. "It seems to this calculation because of the ponding effect of me impossible that such part of the great ice the constriction. His calculated maximum flow fields as would have drained across the Columbia rate was 1.9 x 10° m'/s (66.1 x 10" cfs), but Plateau could, under any probable conditions, he noted that this erred toward the low side. have yielded so much water as is called for in Nevertheless, he sl.'ited, "it represents the melting so short a time. ... It appears that ice sheets of about 42 cubic miles of ice daily" (Bretz, of three distinct stages of glaciation invaded the 1925, p. 258). He then notes that the insolation borders of this region and may have afforded properties of ice and the total available ice mass conditions of repeated floodings of much smaller north of the Channeled Scabland brings the volume" (Alden, 1927, p. 203). whole concept into doubt. "The writer," he says O. E. Meinzer voiced a commonly held view (Bretz, 1925, p. 259), "has repeatedly been of the Channeled Scabland, ". . . the Columbia driven to this position of doubt, only to be River is a very large stream, especially in its forced by reconsideration of the field evidence to flood stages, and it was doubtless still larger in use again the conception of enormous volume.. .. the Pleistocene epoch. Its erosive work in the These remarkable records of running water on the Grand Coulee . . . appears to me about what Columbia Plateau and in the valleys of the Snake would be expected from a stream of such size and Columbia Rivers cannot be interpreted in when diverted from its valley and poured for a terms of ordinary river action and ordinary valley long time over a surface of considerable relief development. . . . Enormous volume, existing for that was wholly unadjusted to it" (Meinzer, a very short time, alone will account for their 1927, p. 207). He argued that the glacially existence." swollen Columbia could have easily cut the Dry Bretz (1925) then speculated on the somewhat Falls and deposited the great gravel fan of the obscure conditions that produced the Spokane northern Quincy Basin. He described the Quincy Flood. He could only think of two possible ex- Basin as containing an extensive series of ter- planations: (1) a very rapid and short-lived races. Moreover, the high-level channels were climatic amelioration, and (2) a gigantic explained by progressive abandonment as the glacial Columbia progressively cut down to in the surface of that flood. The writer, forced lower levels. by the field evidence to this hypothesis, though One difficulty that Meinzer appreciated from warned times without number that he will not his field work in the Ouincy Basin (Schwennes- be believed, must call for an unparalleled rapidity sen and Meinzer, 1918) was the fact that four in the rise of the scabland rivers." Each subse- great spillways led out of the region where water quent study produced yet another affirmation of had obviously been ponded. Bretz (1923a) had the flood theory. Bretz (1930b) writes: "The shown that the upper limits of the torrents that writer, at least normally sensitive to adverse poured through these spillways occurred at the criticism, has no desire to invite attention simply same altitudes. Rather than ascribing this coinci- by advocating extremely novel views. Back of dence to contemporaneous operation, Meinzer ac- the repeated assertion of the verity of the Spokane tually published the idea that the spillways had Flood lies a unique assemblage of erosional forms been cut one at a time, and subsequent minor and glacial water deposits; an assemblage which earth movements had later brought them to an can be resolved into a genetic scheme only if time equivalent altitude. "This recent deformation may be very short, volume very large, velocity very account to some extent for channels cut through high, and erosion chiefly by of the ridges that can not otherwise be well explained jointed basalt." except by assuming excessive depths of flood Among the spectators at the Washington lec- water" (Meinzer, 1927, p. 208). ture was J. T. Pardee. Pardee (1922) also had E. T. McKnight was also a participant in the written on the origin of the Channeled Scabland. Washington discussions. He subsequently sug- W. C. Alden, who was Chief of Pleistocene gested (McKnight, 1927) that a glacially diverted Geology, U.S. Geological Survey, had sent Par- Columbia River was a viable alternative to Bretz' dee to study the scablands. He published a brief hypothesis. In response Bretz (1927b) argued article (Pardee, 1922) proposing that theCheney- that the great flood channels and bars near Gable Palouse scablands tract had been created by Mountain (in the Pasco Basin) were far too large glaciation of rather unusual character. Bretz later to be ascribed to the Columbia River. He made visited Pardee's field locations and found that his his position quite clear (Bretz, 1927b, p. 468): "glacial" deposits were flood bars (Bretz, 1974). "I think I am as eager as anyone to find an Correspondence between Alden, Brctz, and Par- explanation for the Channeled Scabland of the dee suggests that Pardee was really considering Columbia Plateau which will fit all the facts and a hypothesis that the scablands might be related will satisfy geologists. I have put forth the flood to drainage from a large Pleistocene lake that hypothesis only after much hesitation and only he had studied in the western part of Montana when accumulating data seemed to offer no alter- (Fig. 1.2) (Pardee, 1910). It appears that Alden native." dissuaded him from that idea (Bretz, 1974). In Bretz continued to answer various criticisms his memorandum of September 25, 1922, to of his flood hypothesis (Bretz, 1928a, 1928b), and he established some new lines of inquiry into the problem. He (Bretz, 1929) showed that each of the valleys entering the eastern margin of the scabland spillways contained flood deposits em- placed by phenomenally deep water flowing up the tributaries away from the scabland channels. Along the he traced these deposits to beyond Lewiston, , more than 85 miles upstream from the nearest scabland channel. The conclusion again defied conventional wisdom (Bretz, 1929, p. 509): "Upvalley currents of great depth and great vigor are essential. ... No Figure 1.2. Late Pleistocene strandlines of Lake Mis- descending gradient of the valley floor can be soula at Missoula, Montana. The highest strandlines held responsible. The gradient must have existed reach 1280m (4200 feet).

8 David White, Chief Geologist of the U.S.G.S., argued that the scabland phenomena themselves Alden notes of Pardee's work: ". . . very signifi- required the existence of a great flood. cant phenomena were discovered in the region Aaron Waters (in Bretz, 1972) relates that southwest of Spokane. . . . The results so far ... Gilluly was later to change his mind in this require caution in their interpretation. The condi- matter. Many years after the incident at the tions warn against premature publication." David Washington Academy of Science Gilluly visited White later asked Bretz if he knew what Alden's the Channeled Scabland on a field excursion. As middle name was. When Bretz replied in the he observed the Palouse-Snake divide crossing, a negative, White said, "It's Cautious, Bretz, Cau- major scabland stream channel, his astonishment tious." changed to a smiling comment, "How could It seems clear that the source of the great anyone have been so wrong?" Nevertheless, the scabland floods was known even as Bretz was emotion of those days is evinced by the geologists struggling to defend his hypothesis to doubters at who continued to deny the flood hypothesis and the Washington meeting. One story has it that apparently never changed their minds on the mat- during the discussion Pardee leaned over to Kirk ter: W. C. Alden, K. Bryan, W. H. Hobbs, Bryan and said, "I know where Bretz' flood came F. Leverett, C. R. Mansfield, J. C. Merrian, O. E. from." Meinzer, and G. O. Smith. Bretz finally solved the source problem for the The published record of the Spokane Flood Spokane Flood in 1928. Although Harding debate is clear on one major point. Bretz re- (1929) without consultation or acknowledgement peatedly asked only that his flood hypothesis be made the first announcement of Bretz' idea, Bretz considered not by emotion or intuition, but by (1930a) later published the discovery that scab- the established principles of the scientific method. land flooding resulted from an abrupt failure of His detailed paper on the scabland bars contains the ice dam that retained Missoula. the most eloquent expression of this plea (Bretz, Brelz (I932a) clearly illustrated the relationship 1928b, p. 701): of to the Channeled Scabland. James Gilluly was another of those at the "Ideas without precedent are generally looked Washington meeting who was upset with Bretz' on with disfavor and men are shocked if their conceptions of an orderly world are challenged. hypothesis. Although he had not studied the A hypothesis earnestly defended begets emo- Channeled Scabland in the field, he presented an tional reaction which may cloud the protagon- imaginative and persuasive argument for the crea- ist's view, but if such hypotheses outrage pre- tion of the unusual landforms by the long-con- vailing modes of thought the view of antagon- tinued erosion of present-sized streams (Gilluly, ists may also become fogged. On the other hand, geology is plagued with 1927, p. 203-205). He took exception to a minor extravagant ideas which spring from faulty ob- point concerning the use of talus heights as time servation and misinterpretation. They are worse indicators and then attacked the major weak than "outrageous hypotheses," for they lead no- point in the flood hypothesis. At that time the where. The writer's Spokane Flood hypothesis only two explanations offered for achieving the may belong to the latter class, but it can not be placed there unless errors of observation and great volumes of flood water were (1) a very direct inference are demonstrated. The writer sudden climatic amelioration, and (2) subglacial insists that until then it should not be judged volcanism and a resulting glacier burst. Some by the principles applicable to valley forma- simple calculations demonstrate the inadequacy tion, for the scabland phenomena are the prod- of either explanation in producing the required uct of river channel mechanics. If this is in error, inherent disharmonies should establish volumes of water in so short a time. He con- the fact, and without adequate acquaintance cluded, in essence, that Occam's razor did not with the region, this is the logical field for apply to the Channeled Scabland and called for critics." a more complex sequence of adjustments by rivers or floods not much larger than the THE REVISIONISTS Columbia. In reply Bretz (1927a) asked whether the lack of a documented source for the flood By the early 1930's the Channeled Scabland was proof that the flood had not occurred. He problem had become something of a sensation for American geology. Brelz (1932a, I932b) had 1938b, p. 472). It is obvious from Flint's scdi- published the last of his field results, and he had mcntological descriptions that he was giving most embarked on new problems in Greenland and of his attention to the slackwatcr facies of the Alberta and ground-water studies in the U.S. His Missoula flood deposits in the various scabland monumental but controversial field study was now channels. open to the kind of attack that he himself had One of Flint's most important arguments was so strongly urged—new field studies. that the surface form of the scabland deposits Ira S. Allison (1933) was the first to enter was that of "non-paired, stream-cut terraces in the new foray. His view was not a denial of the various states of dissection" (Flint, I938b, p. Spokane Flood, but a modification. He argued 475). It was an idea that Brclz had introduced that it was ice, rather than mere volume, that (Bretz, 1923a) and subsequently rejected after was the critical factor in the flood. He presented closer field study. Flint thought that Bretz' re- detailed evidence for the ponding of flood water vised interpretation of the deposits as construc- all the way from the Columbia River gorge to tional forms could explain some, but not all the Wallula Gap. This ponding was produced of the field relationships. He suggested that a ("in spite of the obvious difficulties of such an sequence of channel aggradation by normal pro- explanation") by a blockade of ice in the Colum- glacial outwash was followed by dissection to bia gorge. The blockade grew gradually headward leave remnants of fill that occasionally resembled until it extended into eastern Washington. As bar forms. water was dammed to higher levels it spilled Flint (1938b) accepted Bretz's (1928b) argu- across secondary drainage divides creating the ments that the flood gravel often (1) occurred enigmatic henggtg valleys, high-level gravels and in the lee of island-like areas, (2) had rounded widely distributed erratics. One of the key in- upper surfaces, and (3) exhibited n parallelism sights of Allison's motivation was in his last sen- of surface slopes with the dip of underlying tence, "perhap this revision will make the idea foresets. He argued that "terraces" had been of such a flood more generally acceptable" (Alli- extensively dissected by a downstream base level son, 1933, p. 722). reduction. The "terraces" were prefentially pre- served in the lee of island-like areas. In addi- Hodge (1934) published a brief interpretation tion, the low precipitation plus the high perme- of the Channeled Scabland involving mainly ability of the gravel prevented gullying, so the glacial processes. He hypothesized a complicated gravel deposits developed rounded slopes by dry alternation of ice advances and drainage changes. creep. Finally, he showed that many of the gravel The basalt was quarried by glacial erosion, and slopes did indeed truncate the underlying channel complexes in the basalt were produced bedding. As specific cases, he argued that Bretz' by the diversion of meltwater streams around Willow Creek bar, Staircase Rapids bar, Palouse blocks of stagnant glacier ice and jams of berg Canyon bar, Midcanyon bar, and Shoulder bar ice. The theory was never adequately supported were all simply terrace remnants. Subsequent by published field evidence. studies have shown that three of these bars have Perhaps the most serious alternative to the prominent on their upper Spokane Flood hypothesis was posed by Richard surfaces (Fig. 1.3). Foster Flint (1938b). In many ways Flint's study Flint also described multiple scarps and 'is one of the most ironic in the annals of geology. benches on the Palouse loess. Instead of record- He presented a carefully worded argument that ing the high-water mark of the Spokane Flood cited a considerable amount of field data. He (Bretz, 1928b, p. 701), he interpreted these stated that the scabland gravel was relatively fine: scarps as evidence of lateral planation by progla- "Gravel coarser than pebble size is common only cial streams. Subsequent studies in the Cheney- in the northern part of the tract" (Flint, 1938b, Palouse scabland by Patton and Baker (Chap. 6, p. 472). This description was combined with the this volume) reveal that these scarps resulted observation of relatively good size sorting and from differential erosion of Palouse Formation fair to good rounding to suggest, "a picture of paleosols and from the exposure of calichificd leisurely streams with normal discharge" (Flint, gravel underlying local areas of Palouse loess.

10 Flint traced the coarse scabland deposits down- of the Snake River today" (Flint, 1938b, p. 515). stream into the Pasco Basin. There he found that As Lake Lewis rose, the "leisurely" streams the deposits changed from sand and gravel to that Flint envisioned aggraded, forming a thick silt and fine sand containing erratic stones. He fill. This fill blocked preglacial tributaries to the named the fine-grained facies the "Touchet beds." Channeled Scabland, such as the Snake River, The deposits had already been described by and formed marginal lakes which accumulated Bretz (I928a, p. 325-328; 1929, p. 516-536; fine-grained sediments. The steep scarps on the 1930b, p. 414), who ascribed them to ponded Palouse loess were then cut by lateral planation flood water; and by Allison (1933), who ascribed of the streams flowing on this Till. When Lake them to water ponded by ice jams. The silts are Lewis finally drained, the streams gradually in- recognized only to a uniform elevation of about cised the fill to form terraces. Moreover, Flint was 350 m. The stratification ranges from rhythmic able to explain the enigmatic notched spurs and parallel bedding to cut-and-fill. The included slotlike hanging canyons as the result of super- erratic stones are granite, basalt, and other position of streams from the widespread fill rather crystalline lithologies. Intense folding, fracturing, than a consequence of divide crossing by cata- and clastic dikes imply slumping and sliding of strophic flood water. the water-saturated silt on gentle subaqueous Flint argued that the complex of anastomosing slopes. Flint thought that these relationships were channel ways cut into basalt was a consequence most consistent with a large lake, which he pro- of erosion by relatively small streams operating posed was ponded by a landslide dam or glacier on various profiles. He stated that scabland-type ice in the Columbia gorge. Following Symons erosion should occur wherever rock material with (1882) he named this water body Lake Lewis. vertical planes of weakness is subjected to stream At this point Flint had the necessary tools to flow. As examples of such erosion he cited Red erect his hypothesis. The proglacial meltwater Rock Pass, Idaho, an outlet of pluvial Lake streams of normal discharge overran the northern Bonneville (Gilbert, 1890). He also noted the margin of the Cheney-Palouse tract. This flow scabland erosion at Twin Falls, Idaho, where was derived from lobes of ice at the heads of the the Snake River flows in a canyon nearly as spec- Cheney-Palouse and Telford-Crab Creek scabland tacular as the scabland channels. He noted, tracts. Flint thought water from Lake Missoula "the . . . [basalt] flows yielded to the hydraulic (Bretz, I930a) need not be involved. Instead, he force of the Snake River as similar flows on the observed that the discharge "was less than that Columbia Plateau yielded to the hydraulic force of proglacial streams, yet I am not aware that unusual floods have been held to have aflected the upper Snake River" (Flint, 1938b, p. 492). These words were written 30 years too soon! Malde (1968) described the catastrophic out- burst of that eroded the scab- land forms at Red Rock Pass and Twin Falls. In yet another ironic passage, Flint (1938b, p. 504-505) calculated the probable rate of filling for Lake Lewis at the modern discharge of the Columbia River. He staled, "the calculated time, 13 years 1 month, seems grossly inadequate for Figure 1.3. Oblique aerial photograph of Staircase the deposition of the fill in the scabland tracts." Rapids bar. The bar is approximately 50 m high and He rationalized his interpretation, however, by composed of coarse flood gravel. The giant current rip- referring back to the interpreted filling episode. ples on the upper bar surface (left foreground) were Bretz' flood theory was so despicable that even actually first described by Flint (1938b) who did not circular reasoning could be employed to erect recognize their origin. Bretz and others (1956, p. 1000- 1002) later used these and other giant current ripple sets an alternative hypothesis. to demonstrate Flint's "faulty reasoning." A careful examination of Flint's (1938b)

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L PAGE IS OF POOR DUALITY paper reveals that he observed and described study. Bretz again reviewed the paper, and again the morphological feature which, more than any it was rejected. Although a brief statement of the other, was absolutely incompatible with his ele- hypothesis was published (Hobbs, 1943), the gant theory. On the surfaces of the scabland main manuscript had to be published privately "terraces" he described an intricate microtopog- (Hobbs, 1947). The author expressed his feelings rapliy of anastomosing channels, small depres- in the "Foreword" to his paper: sions, and crescentic channels (Flint, 1938b, p. 475). In other areas he observed "mamillary un- "In the winter of 1942-43 I was listening with dulatory topography." As an example he gives much interest to a lecture on the late geological history of the so-called Scabland area which is the precise location of the train of giant current southwest of Spokane and close to the supposed .ripples on the upper surface of Staircase Rapids southern front of the Pleistocene Cordilleran Bar, 3 km north of Washtucna (Flint, 1938b, p. continental glacier. A map projected on the 486). Although the ripples that he describes are screen dozens of lakes, none of which trans- somewhat masked by overlying slackwater sedi- gressed its border, an almost sure indication that ments, Flint (1938b, p. 499-500) even states the this lobate area had once been actually covered by a Pleistocene glacier lobe. characteristic ripple magnitude: "The undula- Surrounding this lobe on the lecturer's map tions are 20 to 100 feet long, and have ampli- could be seen a broad apron of gravels, and tudes up to 10 feet. Their axes are generally enveloping the gravels were heavy deposits of transverse to the Snake River." How ironic that silt. These relationships of glacier lobe to out- Flint was the first to accurately describe (without wash and loess duplicated what I had observed in west Greenland. The lecturer explained, how- knowing what they were) the very feature that ever, that the deposits represented upon his map Bretz and others (1956) later presented as in- had been laid down by a great flood of water of controvertible evidence for catastrophic flood unknown origin, the "Spokane Flood." flows (Fig. 1.3)! In the belief that my Greenland observations It was Allison (1941) who published the first had given me an advantage in interpreting the criticism of Flint's fill hypothesis for the origin of evidence within the Scabland region, I then and there decided to make a personal study of it on the Channeled Scabland. The first shortcoming the ground. Although two other very extended noted was that the anastomosing channel patterns studies had already been made of it by Fellows and deep rock basins could not have been eroded of the Geological Society of America, and their by "normal" streams. Second, Allison disputed conclusions had been published in cxlcnso in its' Flint's correlation of the scabland gravels to the Bulletin, the Society provided me with a grant of money which made possible a new study of Touchet beds, suggesting that the Touchet se- the area. This field investigation was carried quence was younger than the gravels. Third, he out during two seasons, and the results and con- agreed with Bretz that the peculiar shapes of the clusions met with unusually enthusiastic general scabland deposits required extraordinary proc- approval when they were presented to the Soci- esses. The conclusion was that the complex jam- ety in 1945 at its Pittsburgh meeting. Following ming of various channels with ice was the only tumultuous applause in the crowded section the discussion was throughout approving." reasonable explanation for the unusual drainage patterns and depositional features. Another example of the strong emotions The Hobbs paper contains so many funda- evoked by the Spokane Flood controversy in- mental errors that one marvels at the absurd volves W. H. Hobbs, an eminent glacial geologist limits that were being stretched to find an alterna- from the University of . He spent sev- tive to catastrophic flooding as the cause of the eral weeks studying the terrain in southeastern Channeled Scabland. Hobbs (1947) argued that Washington and prepared a paper explaining the the scabland was a product of glacial scour and landforms as the product of a "Scabland Glacial that the Palouse loess was deposited contempo- Lobe." Both Bretz and Flint reviewed the paper raneous to this glaciation by anticyclonic winds for the Geological Society of America, and both off the ice that lay in the various "channels." He recommended rejection. The paper was then sub- interpreted many scablund gravel deposits as mitted to the American Philosophical Society, remnants modified by glacier-border which had supplied part of the funds for the drainage.

12 VINDICATION work in the Channeled Scabland. The purpose was to investigate new data that had been ob- At long last Pardee (1942) shared his observa- tained in surveys for the Bureau of Reclamation's tions of Glacial Lake Missoula that firmly indi- Columbia Basin project. Professor H. T. U. Smith cated its role as the source of catastrophic floods accompanied him, acting in the field as "skeptic through the Channeled Scabland. He noted that for all identifications and interpretations" (Bretz about 500 cubic miles of water were impounded and others, 1956). With the aid of Mr. George behind a glacial lobe which occupied the basin E. Neff of the Bureau of Reclamation that study of modern Lake Pend Oreille in northern Idaho. (Bretz and others, 1956) answered with meticu- Pardee believed that this glacial dam had failed lous detail all previous criticisms of the flood hy- suddenly with a res'iltant rapid draining of the pothesis. lake. Evidence for this failure included severely Central to the 1956 investigation was the study scoured constrictions in the lake basin, huge bars of the scabland depositional features. Extensive of current-transported debris (Fig. 1.4), and giant excavations for the irrigation project and new current ripple marks with heights of SO feet and topographic maps proved that the gravel hills spncings of 500 feet (Fig. 1.5). Lake Missoula called bars by Bretz (1928b) were indeed that, was the obvious source for the catastrophic flood subfluvial depositional bedforms. Most convincing flows required by Bretz' hypothetical origin of of all was the presence of giant current ripples the Channeled Scnbland (Fig. 1.6). Pardee did on the upper bar surfaces. These showed clearly not stale the connection, perhaps leaving that that bars 30 m high were completely inundated point generously to Bretz. Even Alden remained by phenomenal flows of water. Numerous exam- cautious to the end. His last published report on ples of giant current ripples were found on the Lake Missoula observed (Alden, 1953, p. 155): same bars which Flint had interpreted as ter- "Abrupt release of water from lowering of the ice races. Such features could only have been pro- dam . . . might result in floods of great magni- duced by the flow velocities associated with truly tude. . . . Each may, perhaps, have been the catastrophic discharges. Bretz and others (1956) origin of many violent floods that are supposed and Bretz (1959) modified Bretz' earlier inter- to have swept over the scablands." pretations to allow for several episodes of flood- In the summer of 1952, Bretz, then nearly 70 ing. The central theme of their study, however, years old, returned for his last summer of field was that only a hypothesis involving flooding could account for all the features of the Chan- neled Scabland. More recent studies of the

Figure 1.4. Large "gulch fill" formed at the mouth of a tributary canyon along the Flathead River, Perma, Montana. The deposit is an eddy bar (Baker, 1973a) Figure 1.5. Giant current ripples at Camas Prairie, formed during the rapid draining of glacial Lake Mis- north of Plains, Montana. The ripples are composed of soula. First recognized by Pardee (1942) this gravel de- gravel and consist of ridges up to 15 m high and spaced posit was Inter breached by a small stream to form the as much as 200 m apart. The ripples cover approximately V-shaned notch visible at right. The low terrace in the 10 km' of the northern Camas Prairie. Faint strandlines foreground is composed of lacustrine silt. of Lake Missoula are visible in the background.

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• ;",!N'AT, PAGK IS (Ji- i'OUiv UUAUTV IDAHO) MONTANA

MISSOULA

GLACIAL LOBE GLACIAL LAKE MISSOULA (EARLY PINEDALE1

EARLY PINEOALE AXIS OF MAJOR FLOODING ANTICLINAL RIDGE

Figure 1.6. Relationship of glacial Lake Missoula to Ihe Channeled Scabland of eastern Washington (Baker, 1973a).

Quaternary geology of eastern Washington have DISCUSSION accepted this reasoning (Trimble, 1963; Fryxell and Cook, 1964; Richmond and others, 1965; When Bretz published his work on the Chan- Baker, 1973a). neled Scabland, the paradigm of Geology was uni- Perhaps the final words on the Channeled formity. The Spokane Flood hypothesis appeared Scabland controversy were delivered following a to contradict the uniformilarian tradition that field trip, Field Conference E of the 7th Congress, made geology a science in the nineteenth century. International Association for Quaternary Re- Indeed it was not until after 1840 that the flood search. During August, 1965, an international theory fell into serious decline. The catastrophist party of geologists observed the evidence in Mon- idea of the Noachian debacle was finally laid to tana for Lake Missoula's catastrophic outbursts. rest when Louis Agassiz showed that his glacial They then traveled through the Channeled Scab- theory could explain erratics, striations, till, flu- land studying the giant current ripples, flood vioglacial activity, etc. Old ideas die hard, how- gravel bars, and scabland erosion forms. Dr. ever, and catastrophist absurdities still appeared Bretz was unable to attend the trip because of in the literature of the early 1900's (as they do health. When the field party reached Pullman, even today). Little wonder then that Bretz' Spo- they sent a long telegram to him at Homewood, kane flood hypothesis appeared as an anathema . The telegram opened with "greetings and to many of his contemporaries. salutations" and closed with the sentence, "We Simultaneously the Spokane Flood hypothesis are now all catastrophists" (Bretz, 1969, 1973). established a conflict between two important cor-

14 ncrstones of geological philosophy: (1) the tri- was fighting for my professional career." (Quota- umph of the glacial theory over diluvian myth, tion of Dr. Bretz by the Seattle Times, July 11, and (2) the scientific tolerance of outrageous hy- 1971.) Bretz himself explored the consequences potheses. It is a classic dilemma for the scientist of his "outrage." His 1956 paper resoundingly to distinguish absurdity from outrage. A foolish confirmed the catastrophic flood theory by idea is always self-evident, but not so with the answering in meticulous detail all the previous ob- rare, creative insight that happens to pass all rea- jections to his grand hypothesis. It took over 30 sonable bounds in the consensus of knowledge. years and the coming of a new generation of The remarks of a former president of our society: geologists for his theory to gain general accept- "How narrowly limited is the special field, either ance. in subject or locality, upon which a member of The Spokane Flood controversy is both a story the Geological Society of America now ventures of ironies and a marvelous exposition of the to address his colleagues.... I wonder sometimes scientific method. One cannot but be amazed at if younger men do not find our meeting rather the spectacle of otherwise objective scientists demure, not to say a trifle dull; and whether they twisting hypotheses to give a 'uniformitarian ex- would not enjoy a return to the livelier manners planation to the Channeled Scabland. Un- of earlier times . . . (Their) feeling of discour- doubtedly these men thought they were upholding agement must often be shared by the chairman of the very framework of geology as it had been a meeting when, after his encouraging invitation, established in the writings of Hutton, Lyell, and 'This interesting paper is now open for discus- Agassiz. The final irony may be that Bretz' critics sion,' only silence follows.... We shall be indeed never really appreciated the scientific implications fortunate if geology is so marvelously enlarged of Agassiz' famous dictum, "study nature, not in the next thirty years as physics has been in the books." Perhaps no geologist has understood and last thirty. But to make such progress violence lived the spirit of those words more enthusiast- must be done to many of our accepted principles." ically than J Harlen Bretz. After speaking these words in 1926, William As the Viking spacecrafts were orbiting Mars Morris Davis made a case for the value of out- in the summer of 1976, the cameras were trained rageous geological hypotheses, even suggesting on the great Martian channel systems. They re- that geologists seriously consider "the Wegener vealed uplands streamlined by fluid flow, eroded outrage of wandering continents." He concluded scabland on the channel floor, and many other by saying that the valuable outrage was that which features that we now know to be diagnostic of encouraged the contemplation of other possible bedrock erosion by catastrophic flooding. Fifty behaviors. Such outrages deserve contemplation years after J Harlen Bretz' theory of scabland followed not, he states, "by an off-hand verdict erosion on the Columbia Plateau was being de- of 'impossible' or 'absurd', but a contemplation nounced at an infamous meeting of the Washing- delibrate enough to seek out just what conditions ton Academy of Science, Viking scientists were would make the outrage seem permissible and using Bretz' well-documented studies of the Chan- reasonable." neled Scabland as the major earth-analog to Needless to say, W. M. Davis was one of the Martian channel erosion. Few geological con- first to accept Bretz' interpretation in the 1920's. cepts, born amid bitter controversy over a half It is a commentary on those years that others century ago, have continued to have such rele- were not so tolerant. "During all those years, I vance to our science.

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