GEOSCIENCE REPORTS
Summer 1997, No. 24
SPECIAL ISSUE
CATASTROPHISM IN THE PACIFIC NORTHWEST:
A GEOSCIENCE RESEARCH INSTITUTE FIELD GUIDE
Harold G. Coffin, Senior Research Scientist (retired)
Elaine G. Kennedy, Geoscience Research Institute
FIGURE. Stumps and logs strewn by the 1980 Mount St. Helens eruption can still be seen along the banks of the Toutle River.
FIELD GUIDE
MOUNT ST. HELENS
Location: Mount St. Helens National Volcanic Monument, southwestern Washington. The Monument may be reached from I-5 on the west or Highway 12 on the north.
On May 18, 1980, a 4.9 magnitude earthquake preceded the eruption of Mount St. Helens. The eruption removed over 400 meters from the top of the mountain. The hot, ash-filled gases blasted northward and the effects were devastating. Over 60 people and thousands of animals were killed. Millions of trees, over an estimated 620
km2, were blown down. Most of the remaining upright trees within the blow-down region are dead with the exception of a few surviving stands in sheltered
areas.1 Snow and ice (melted during the eruption) and concurrent heavy rainfall flooded both forks of the Toutle River with mud that destroyed lumber camps and bridges.
Studies along the north fork of the Toutle River indicate that rocks, mud and fluids (debris flow) traveled at about 145 km/hr over a 24 km
distance.2 The contact between the debris flow and the underlying sediments suggests that the flow was lubricated by a layer of hot gases. In addition, the debris flow transported tree stumps in an upright
position.3 The stumps can be seen scattered along the mudflats and gravel bars of the north fork. One stump, 2 m in diameter and 14 m tall, is located near the toe (distal portion) of the flow. Transport of such a large stump is typical of the high energy system associated with the eruptive processes.
Discussion: The catastrophic effects of the eruption of Mount St. Helens provide a modern analog for similar features observed in other volcanic deposits and preserved in the geologic record. Specifically, the effects noted at Mount St. Helens can be compared to the record of volcanism and destruction of fossil forests at several localities in Yellowstone National Park.
SPIRIT LAKE
Location: South from Randle, Washington, walk trail from main road within Monument to the lake.
The eruption of Mount St. Helens caused the water level in Spirit Lake to oscillate. The violent changes in the water level eroded the lower slopes around Spirit Lake and stripped them of their trees and soil. Debris on the lake contained logs floating both horizontally and vertically. Many of the upright stumps had roots that were lightly grounded in the shallow water of the lake. Other trees were free-floating, vertically in the water column. Sonar transects covering <1% of the lake bottom revealed 154 upright stumps and 95 logs lying horizontally on the lake floor.4
Discussion: Floating stumps in Spirit Lake and the transported stumps along the Toutle River occurred as the result of a volcanic eruption. However, both mechanisms could occur during any catastrophe having sufficient water energy to erode and transport trees.
The processes involved here at Spirit Lake may be comparable to the processes responsible for the deposition of the petrified, upright stumps found in outcrop at Yellowstone National Park. Similarities in orientation and distribution of the trees are difficult to establish due to the limited outcrops in Yellowstone; however, physical attributes can be compared, e.g., condition of the root balls as well as that of bark and limbs.
Conclusions from Mount St. Helens
The events that occurred at Mount St. Helens provide a modern analog for the erosion, transport and deposition of the petrified stumps in Yellowstone. The primary feature used to identify in situ fossil "forests" in Yellowstone National Park is the presence of upright stumps. Transport of upright stumps by two mechanisms (mud flows along the Toutle River; erosion due to rise in lake level) has been documented at Mount St. Helens. These models have important implications with regard to the time required for the deposition and preservation of the stumps. Furthermore, the energy and devastation associated with this catastrophe has occurred on a rather small scale when compared with similar events in the geologic record. Such local catastrophes provide small glimpses of the processes involved in the much larger devastation of our earth during the worldwide flood recorded in Genesis. These events should inspire Christians to review their concepts of the Noahic flood in terms of its complexity and fluctuating energy levels during and after the flood year.
COLUMBIA RIVER BASALTS
Location: Numerous roadside deposits of Columbia River Basalts occur across the State of Washington. Basalt pillows in palagonite are located on Hwy 26, 1.2 mi from 1-90 exit 137. Pull-off on right.
Multiple, horizontal layers of dark rocks (lavas/basalts) are exposed in outcrop across the State of Washington. These layers are referred to as the Columbia River [Flood] Basalt Group and cover an area of about 200,000 km2 (refer to Figure 1 on p 10 of this issue).5 K-Ar and Ar-Ar radiometric dating methods have been used to estimate the age and time required to deposit the basalt flows (Figure 2; p 11 of this issue), i.e., 17.5-6 million years BP.6 (This time frame is not endorsed by GRI.)
Discussion: These extensive lava flows may not have required 11 million years for their distribution. Many of the layers within these deposits have similar trace element geochemistry and could be reevaluated with regard to the amount of time allowed between eruptions. In addition, the Ellensburg Formation (river deposits) occurs both within and above the Columbia River Basalt Group.7 This relationship suggests more rapid depositional processes since the source material for these sedimentary deposits remained relatively similar throughout the period of deposition of the flood basalts. The absence of erosion between most of the layers also suggests that no significant time elapsed between flows. Volcaniclastics from the Cascade Range incorporated into the Ellensburg formation could also be examined geochemically for clues to the timing of the deposition.
COLUMNAR BASALT
Location: From Vantage, Washington, take I-90 east (7.6 mi) to Exit 143 Silica Road and drive (0.8 mi) to Vantage Road highway, turn left. Drive to basalt columns (1.2 mi).
Basalt may exhibit structures called columnar jointing. As the molten lava cools (solidifying at about 1000°C) and contracts, prismatic "columns" form along parallel fractures or joints. The cross-section of each of these columns has the shape of a polygon. The columns may be 4,5 or 6-sided within the same layer. Concave cross-joints or horizontal fractures are also common.8 Such structures may form subaqueously in welded tuffs.9 It has also been suggested that narrow columns represent rapid cooling times.10 In addition, the entablature structures that commonly overlie the columnar joints in the same basalt flow, are generated by contact with a large influx of water implying that waters flooded over the top of the lava.11
Discussion: Time is required for the cooling of the lavas, deposition of sands and gravels in some instances, and flow of each lava bed. Time required for these deposits has been measured in millions of years according to the radiometric dates. This time frame is not acceptable to the Creationist community. The actual processes could have occurred over a period of months during the waning stages of the Noahic Flood or over a period of years and even hundreds of years after the Flood.
BOULDER
Location: From Ephrata drive east on Hwy 282, turn north (left) onto Hwy 17. From Jct. 282/17 drive 3.9 mi to Hatchery Road (gravel) and turn right. Stop beside big rock on left (0.7 mi).
Some have postulated that this boulder represents an ice rafted glacial erratic. However, glacial erratics mark the distal position of the Okanagan Lobe of the ice sheet from British Columbia that extended to about 8 km west of the Dry Falls State Park. So that scenario is unlikely. Others think this boulder, with an estimated weight of 1000 tons, rolled at least 15 km south from the mouth of Lower Grand Coulee to this locality during one of the Missoula floods. In support of this position, note the evidence of current scour (water erosion) around the rock and especially on the lee side of the rock.
Discussion: This boulder was eroded, rounded and transported by a regional flood. The Missoula Floods are almost insignificant when compared to the catastrophe described in Genesis. Mass transport during the Noahic flood is probably responsible for the megabreccias containing much larger boulders that are found in the geologic record.12
SITE OF RHINOCEROS MOLD
Location: Drive north from the town of Soap Lake to Park Lake Road (13.7 mi) and turn right. Drive to Laurents Resort (0.6 mi) and park. Rhino mold may be reached by renting row boats or hiking the trail back of the resort.
At Blue Lake there is a mold of a rhinoceros in the lower portion of one of the basalt layers. Apparently, the carcass of a rhino was lying on a thin deposit of the Ellensburg Formation and it was covered by the Wanapum Basalts in the Grande Ronde lavas (Figure 2). After the region was eroded, caves were discovered in the lava flows. In one cave were the bones of a rhino. The contours of the interior of the cave, revealed the body shape, the front legs, head and even the horns on the head of the rhino.
Discussion: The presence of the sand and gravel deposits from the Ellensburg Formation between two lava flows with the entombed rhino indicates the passage of time during the deposition of the Columbia River Basalt Group. After the lower basalt layer was deposited, sands and silts accumulated across the lava flow. Whether the rhino died at this location or died elsewhere, bloated and then floated to this locality, is not known. It is clear that some time passed (hours, months, years?) between the lava flow that underlies this formation and the deposition of the next (overlying) flow that buried the rhino.
DRY FALLS
Location: Viewpoint is on U.S.Hwy 2 opposite the Jct. with Hwy 17 north.
More than 40 cataclysmic floods are believed to be responsible for the erosion of the scablands of eastern Washington. The waters for these floods came from glacial lakes in western Montana. The initial and largest flood event occurred when the ice dam blocking the Clark Fork River failed. This rupture resulted in the emptying of Lake Missoula. It is this cataclysmic event that is thought to be responsible for the maximum erosion in the region. Subsequent floods from ice dam failures, each somewhat smaller than the previous one, continued to contribute erosional and depositional features. Dry Falls, within the Grand Coulee, must have been a gigantic cataract as the waters raged across this region. The Falls extend 5-6 km in width with a drop of more than 100 meters. Plunge pools can be seen at the base of the Falls.13 Maximum rate of water flow across this region has been estimated at 40 km3 per hour.14
Discussion: The erosive power of waters draining across the land during a regional flood (for which we see considerable evidence in eastern Washington) should be carefully considered as we look at evidence and criteria that may support our belief in the occurrence of the worldwide flood recorded in Genesis. Large-scale erosion would be expected as flood waters drained from the continents into the new, post-flood oceans. One region that merits consideration in this context is the canyons in southern Utah and northern Arizona.
GIANT RIPPLE MARKS
Location: From Interstate 90 at St. Regis, Montana, Location: From Interstate 90 at St. Regis, Montana, take Hwy 135 east to Markle Pass. The Giant ripple marks are on the south side of the Pass.
Markle Pass, near the mouth of the Clark Fork River, is the starting point for the numerous features (gravel bars, scour, erratics, falls and coulees) created by the flood events that extended westward across the states of Idaho and Washington. Blocked by an ice dam, glacial Lake Missoula extended from this pass eastward. Each time the ice dam ruptured, glacial waters gushed through this pass at a rate of 400 million ft3 per second (c.f.s.). [The Amazon's rate of flow is 6 million c.f.s.]15 The time required to empty Lake Missoula has been estimated at 2 days.16 The gravel ridges south of Markle Pass are actually giant ripple marks created as water (at least 260 m deep) poured across the gap. Water depth and rate of flow were estimated from the size of the ripples. The ripples are 10 m high and extend about 115 m from crest to crest. Some of the ripples are more than 3 km in length.17
Discussion: It was difficult for researchers to establish the gravel ridges south of Markle Pass as ripple marks. Such gigantic features were unknown prior to this work and it was difficult for workers to mentally visualize such large-scale ripple structure. Due to the physical extent of these structures, an aerial view provides the most convincing argument for their identification as ripple marks. Since the Missoula Flood events were small-scale when compared to the Genesis flood account, such observations should encourage us to expand our thinking relative to that universal flood.
Conclusions from the Scablands of Washington
The effects of the series of Missoula Floods on the surface topography of the Scablands of eastern Washington provide insight into the nature of regional, catastrophic erosion (primarily) and deposition. Erosional features such as the coulees and dry falls may be comparable to the erosional plateaus and mesa of southeastern Utah. Final stages of regional drainage during the drying phase of the Noahic flood may have generated numerous large-scale features as yet unrecognized as such.
Some Tertiary lakes may have been created as flood waters were trapped in basins during the final flood stages. After the flood as these lakes dried up over a period of years, similar phases may be compared from the rock record, i.e., increased salinity and dessication features. A variety of organisms may have begun the process of repopulating the region and subsequent regional catastrophes may have buried the organisms in the highly mineralized waters of some of these Tertiary lakes, leaving a post-flood record.
It is important but difficult to develop criteria for identifying various stages of the Noahic flood. It is equally important and perhaps more difficult to define the criteria marking the end of the flood in the rock record. Large-scale erosional features indicative of multi-regional drainage may provide one type of criteria that would be useful for identifying the waning stages of the worldwide flood.
SPECIMEN CREEK: FOSSIL "FORESTS"
Location: From the junction of Hwys 287 and 191 drive north 16.6 miles to Specimen Creek, cross the creek and turn right into the Specimen Creek parking area. Park and hike with guide.
The presence of upright, petrified stumps in a vertical sequence of volcanic, debris flow deposits (lahars) in Yellowstone National Park have been used as evidence for the in situ development of a series of forests.18 Thin layers of silt, sand and minor clays containing leaves, seeds, and other plant fragments were thought to be primitive soils.19 Researchers had concluded that each forest had been destroyed by some natural disaster, buried and then new forest had grown on top of the old forest. In the Specimen Creek area 48 levels of trees have been identified (Coffin, pers. com.).
Discussion: Research conducted by numerous Seventh-day Adventist scientists in recent years has provided a growing list of evidence to support a model for transport and deposition of petrified wood and stumps in Yellowstone National Park.20 In addition, the documentation at Spirit Lake of upright stumps transported during catastrophic volcanic activity has provided a modern analog for the alternative interpretation posed by these scientists. Research in the petrified forests of Yellowstone has demonstrated that creation science can significantly contribute to scientific studies and enhance our understanding of earth history.
MOUNT HORNADAY: FOSSIL "FORESTS"
Location: West 12 miles from Silver Gate on Hwy 212 to Pebble Creek Campground. Park and hike with guide.
Mount Hornaday is on the eastern side of Yellowstone National Park, more than 70 km from the Specimen Creek site located in the northwest comer of the Park. The mountain lies northeast of additional deposits of petrified "forests" at Specimen Ridge and Amethyst Mountain and east of the deposits in the Tom Miner Basin. Working conditions are more rugged at this locality. The layers and features that can be seen here are very similar to the deposits at Specimen Creek.
Discussion: Areal extent of the fossil "forest" deposits is approximately 2,000 km2. Distribution of wood from multiple environments over a broad area is difficult to model. Recent research suggests that multiple volcanic sources contributed material to the intercalated ash beds within the debris flows (Webster, pers. com.). Eruption events probably triggered the movement of these massive flows through ecologically diverse forests. Plant material was uprooted, transported, deposited and rapidly silicified so that structure was preserved on the cellular level. This regional catastrophe was a small-scale event when compared to the Genesis flood. However, the diversity of the plants suggests to some that this deposit may have required large-scale transport. If so, it could have occurred in the latter stages of the flood.
CATHEDRAL CLIFFS
Location: From Jct of 212, drive east on Hwy 298, turnout on right.
At Cathedral Cliffs the basal Bighorn Dolomite (Ordovician) is overlain by the Jefferson (dolomite, Devonian) and Three Forks (shale, Devonian) Formations and capped by Tertiary volcanics. Structures that appear to be dark spaces in the cliffs are actually intruded, dark volcanic rocks (mafic dikes). The Heart Mountain thrust fault lies at the top of the Grove Creek Formation (Cambrian) and is best identified by the abrupt termination of the dikes at the base of the Bighorn Dolomite. The underlying Cambrian deposits include (from the base) Flathead and Gros Ventre Formations, the Pilgrim Limestone and Snowy Range Formation. Basement consists of granitic pre-Cambrian rocks. To the east the fault plane crosses the section and Paleozoic rocks of Heart Mountain overlie the Willwood Formation (Eocene).21
Discussion: Two models have been proposed to explain the distribution of these Paleozoics. The tectonic denudation model employs a series of catastrophic events to account for the distribution of the blocks: detachment, sliding and post-depositional volcanism; whereas the continuous allochthon model relies on gravity driven extension of the region. Recent research indicates that volcanic gases may have catastrophically contributed to the spreading process.22
Conclusions from Yellowstone
The regional catastrophism associated with the Yellowstone fossil "forests" and the catastrophe linked to the Heart Mountain detachment fault indicate that some rethinking with respect to the magnitude of such events needs to be done. The displacement of the trees in the lahars and the nearly lateral displacement of the slide blocks over such broad areas in a very brief amount of time suggest a powerful triggering event. It should be reasonable to assume that other volcanic events throughout the geologic record would have equally widespread effects.
Due to the complexity and magnitude of a worldwide flood, scientific models are needed to test ideas. Research conducted on regional catastrophes may be applicable to Noahic flood models. However, such research cannot prove that a worldwide flood has ever occurred.
ENDNOTES
Figure 1. Extent of the Columbia River Flood Basalt Group. Black box identifies the region of the fissures supplying source material for the flood basalts. Modified from Reidel and Tolan 1992.
COLUMBIA RIVER BASALT GROUP
SADDLE MOUNTAINS BASALT LOWER MONUMENTAL MEMBER 6 my ICE HARBOR MEMBER 8.5 my Basalt of Goose Island Basalt of Martindale Basalt of Basin City ======================================== BUFORD MEMBER ELEPHANT MOUNTAIN MEMBER 10.5 my ======================================== POMONA MEMBER 12 my ======================================== ESQUATZEL MEMBER WEISSENFELS RIDGE MEMBER Basalt of Slippery Creek Basalt of Tenmile Creek Basalt of Lewiston Orchards Basalt of Cloverland ASOTIN MEMBER 13 my Basalt of Huntzinger ======================================== WILBUR CREEK MEMBER Basalt of Lapwai Basalt of Wahluke ======================================== UMATILLA MEMBER Basalt of Sillusi Basalt of Umatilla ============================================ WANAPUM BASALT PRIEST RAPIDS MEMBER 14.5 my Basalt of Lolo Basalt of Rosalia ======================================== ROZA MEMBER FRENCHMAN SPRINGS MEMBER 15.3 my Basalt of Lyons Ferry Basalt of Sentinel Gap Basalt of Send Hollow Basalt of Silver Falls Basalt of Ginkgo Basalt of Palouse Falls ECKLER MOUNTAIN MEMBER Basalt of Shumaker Creek Basalt of Dodge Basalt of Robinette Mountain ============================================ GRAND RONDE BASALT SENTINEL BLUFFS UNIT 15.6 my SLACK CANYON UNIT FIELD SPRINGS UNIT WINTER WATER UNIT UMTANUM UNIT ORTLEY UNIT ARMSTRONG CANYON UNIT MEYER RIDGE UNIT GROUSE CREEK UNIT WAPSHILLA RIDGE UNIT MT. HORRIBLE UNIT CHINA CREEK UNIT DOWNEY GULCH UNIT CENTER CREEK UNIT ROGERSBURG UNIT TEEPEE BUTTE UNIT BUCKHORN SPRINGS UNIT 16.5 my IMNAHA BASALT 17.5 my Figure 2. Stratigraphic nomenclature for the Miocene Columbia River Basalt Group. Modifed from Reidel et al 1989. The time periods of millions of years are not endorsed by the Geoscience Research Institute. The heavy double lines (=) denote erosional unconformity.
EDITOR'S ANGLE
This issue of Geoscience Reports is an effort on our part to supply teachers with some information about a geologically and historically interesting region in the form of a field guide. In this format, any portion of the material can be used for a class trip, outdoor school, or other special program. We hope to produce a series of these guides. In addition, the materials are designed to encourage discussion on the interface between science and religion from information visible in outcrop and from the information included in the written materials. We would appreciate knowing whether a series of these issues will be of value to our secondary-level science and Bible teachers.
Geoscience Reports
Sunmer 1997 No. 24
Editor - Elaine G. Kennedy
Associate Editor - Katherine Ching
Subscription requests, correspondence, and notices of change of address should be sent to: Publications Editor, Geoscience Research Institute, Loma Linda University, Loma Linda, CA 92350 USA. Annual subscription rate is $3.00 (US. currency).
Geoscience Reports is a newsletter published by the Geoscience Research Institute to present current happenings at the Institute as well as general-interest articles that deal with creation/ evolution issues for elementary/secondary-school and college science classes. The views expressed are those of the authors and not necessarily those of the Institute.
Staff of the Institute: L Jim Gibson, Director (PhD, biology); Ben L Clausen (PhD, nuclear physics); Elaine G Kennedy (PhD, geology); Clyde L Webster (PhD, chemistry); Katherine Ching, Editor (MA, history); and Janet Williams, Administrative Secretary.