Varves: Problems for Standard Geochronology
By Kurt Howard, B.S., M.S.
Edited by Jon & Anita Covey
In the fall 1994 issue of Science Speaks, Don Stoner (1994) stated that the Green River Formation of Utah, Colorado and Wyoming "contains more than four million annual layers." He then says, "Obviously, this means that the lake existed for millions of years before it disappeared." Our discussion here will address the question of varve chronology or clock and shows that laminar deposits (sediment in thin sheets) do not necessarily indicate seasonal deposits. A true varve consists of a couplet of summer silt and winter clay, a period that is difficult to demonstrate. (Quigley, p. 150) The abstract in Michael Oard's series on varves states:
Varves have been used to set up the first "absolute" chronology, which significantly exceeds the Scriptural time scale from Genesis. Observations of modern glaciers and recent climate simulations show that the ice sheets during the Ice Age melted rapidly, much faster than indicated by varves. A further investigation of varves demonstrates that other mechanisms deposit varve-like couplets in a short time. Therefore, "varves" are not necessarily annual. A method to distinguish between annual depositional sequences and other mechanisms is difficult to apply. (Oard, p. 72)
The varve-like laminations found in the Green River Formation and, indeed, the entire geohistory of Lake Gosiute in which the sediments were deposited have been the subject of changing views for many decades. Fischer and Roberts (1991) say, "a voluminous literature records varied interpretations of these deposits." and "...the pendulum of changing opinion..." has swung from one model to another and "... the nature of the lake has been controversial.... The differences of opinion involve fundamental matters such as the source of the organic material, the source and mechanism for formation of the carbonate laminae, the cause of the cyclic laminations, and which laminations geologists use to define a varve.
Origin Of Lamina Materials
In one model, geologists perceive the organic material comprising the laminations coming from a rain of organic detritus produced by plankton living near the upper level of the lake (Bradley, 1929). Another states that microbial mats growing in shallow pools and shoreline zones on the margin of the lake produced the organic material (Surdam and Stanley, 1979). A third says the photosynthetic activity of the phytoplankton that draw CO2 from the lake water, raising the pH and in turn causing calcium carbonate to precipitate, produces the carbonate laminae (Bradley, 1929). This does not happen in ocean water because the salt ions react with the silt and clay particles causing them to sink to the bottom of the ocean and form a featureless deposit. (Oard, p. 72) Another view attributes the carbonate laminae to calcium rich streams entering saline, alkaline lake water (Boyer, 1982). Others suggest that the calcium carbonate laminae arose from dust storms blowing off the carbonate mudflats surrounding the lake (Bradley, 1929, Surdam and Stanley, 1979).
Mechanism Of Cyclic Lamination Formation
One opinion holds that the cyclic laminations are the result of periodic algal blooms (Eugster and Surdam, 1973). Bradley explained that periodic dust storms sweep carbonate dust from the mudflats surrounding the lake (Bradley, 1929). Kurt (our author) proposes another mechanism for varvesspontaneous segregation of heterogranular material falling in still water.
Julien, Lan and Berthault (1994) experimentally produced laminations by slowly pouring mixtures of sand, limestone and coal into a cylinder of still water. Using a variety of materials, they found that laminae formed if there were differences in size and density of the materials and that the thickness of the laminae depended upon differences in grain size and density.
Inconsistent Varve Counts
Buchheim and Biaggi (1988) measured Green River Formation "varves" between two volcanic tuff beds each two to three centimeters thick. Geologists consider each tuff bed a synchronous layer, i.e., every point on that tuff bed has the same age. The two tuff beds thus represent two different reference times. If the laminations in between these two beds are annual layers, the same number of layers should be present everywhere between the two beds. Buchheim and Biaggi found the number of laminae between the tuff beds ranged from 1160 to 1568. Lambert and Hsü (1979) measured "varves" in Lake Walensee, Switzerland and found up to five laminae deposited during one year. From 1811, which was a clear marker point (because a newly built canal discharged into the lake), until 1971, a period of 160 years, they found the number of laminae ranged between 300 and 360 instead of the expected one per year or 160.
Fischer and Roberts (1991) state, "In some cases the observer counting varves is left in doubt as to which couplets are varves and which are subvarve units, a matter that was handled in our image analysis varve counts by arbitrarily counting only variations above the 30 micron level." In other words, they arbitrarily chose 30 microns as the minimum thickness to be used for computer analysis. However, many laminations are less than 30 microns thick. Also, many of the "varves" consist of organic layers squeezed together with very tiny carbonate laminae in between. There is no consistency in varve structure.
Other Nonseasonal Causes Of Lamination
Geologists have suggested other causes of lamination as potential contributors to varves, including storm events, turbidites and glacial meltwater. Each one of these is aperiodic, producing laminations with no relation to annual, cyclic processes. For example, turbidity currents from melting snow or heavy rain produce extra couplets.
Our investigations supported de Geer's first contention that sediment-laden floodwaters could generate turbidity underflows to deposit varves, but threw doubt on his second interpretation that varves or varve-like sediment are necessarily annual.
Turbidity currents can mimic varves, especially at the end of the flow that is farthest from the source or sediment. (Hambrey) Many supposed varves are multiple turbidity current deposits and do not represent seasonal changes.
It is very unfortunate from a sedimentological viewpoint that engineers describe any rhythmically laminated fine-grained sediment as 'varved.' There is increasing recognition that many sequences previously described as varves are multiple turbidite sequences of graded silt to clay units...without any obvious seasonal control on sedimentation. (Quigley, p. 151)
Turbidity flows have the surprising ability to deposit silt and clay quickly in equal thicknesses. Under normal conditions, silt usually settles in a few days and clay can take years to settle.
As both clay and silt fractions are transported to the site of deposition at the same time, successive surge deposits are likely to have similar proportions of silt and clay. In other words, thick silt layers will have thick clay layers, and thin silt layers will have thin clay layers. (Smith, pp. 198-199)
Turbidity flows are independent of season and can continuously deposit microlaminae throughout the year, including the winter:
In many cases where large ice lobes or glaciers sit or float in lakes, there is year round delivery of sediments and turbidite activity occurs almost continually resulting in graded laminae that are not true varves. (Quigley, p. 152)
How many varve-like layers form from year to year becomes anyone's guess. Wood (1947) describes peak river inflows after light rain that deposited three varve-like couplets in two weeks. Just as we have seen in many situations, e.g., stalagmite and canyon formation, strata deposition, and fossilization, time is not the essential factor for their development, although evolutionists insist that such things took much time to form. While evolutionary catastrophists admit rapid formation, they almost invariably propose long periods of tedium between catastrophic events. (Ager)
Steve Austin, who has done much field work at Mount St. Helens, documented in his new book Grand Canyon: Monument to Catastrophe that the volcano eruption produced 25 feet of volcanic ash varve-like deposits from hurricane-velocity surging flows in five hours.
We do not intend to deny the capability of seasonal variations to produce annual layers. The intent is to show that many varve-like deposits do not represent annual processes. The following summarize why we must be cautious when evaluating laminar deposits:
Controversy exists as to the source material comprising varves as well as the mechanism of their cyclic formation.
Lamination counts in historically known sections have been demonstrated not to correspond to elapsed years or counts are inconsistent.
There is frequently uncertainty as to how many laminations constitute a varve and the use of arbitrary minimum sizes may lead to erroneous conclusions.
There are many nonseasonal mechanisms for producing laminations such as storms, floods, turbidites, glacial meltwater and spontaneous segregation of dissimilar materials. All of these causes of laminar deposits indicate that varve-like laminations are a common effect of many nonseasonal processes.
In view of the data presented, assertions regarding geochronolgy which rely on varve-like data must be made with caution especially since they deeply affect important issues of faith.
Ager, Derek, 1993, The New Catastrophism, Cambridge University Press, Cambridge, p. xix.
Boyer, B., 1982, Green River Laminites: Does the playalake model really invalidate the stratifiedlake model: Geology, v. 10, p. 321-324.
Bradley, W.B., 1929, The varves and climate of the Green River epoch: U.S. Geological Survey Professional Paper 158, p. 87-110
Buchheim, H.P. and Biaggi, R., 1988, Laminae counts within a synchronous oil shale unit: a challenge to the "varve" concept: Geological Society of America Abstracts with Programs, v. 20, n. 7 p. A317.
Eugster, H.P. and Surdam, R.C., 1973, Depositional environment of the Green River Formation in Wyoming: a preliminary report: Geological Society of America Bulletin, v. 84, p. 1115-1120.
Fischer, A.G. and Roberts, L.T., 1991, Cyclicity in the Green River Formation (Lacustrine Eocene) of Wyoming: Journal of Sedimentary Petrology, v61, n7, p . 1146-1154.
Hambrey, M.J., and W.B. Harland, editors, 1981, Earth's pre-Pleistocene glacial record. Cambridge University Press. Cambridge, p. 14.
Julien, P.Y., Lan, Y., and Berthoult, G., 1993, Experiments on stratification of heterogeneous sand mixtures: Bulletin of the Geological Society of France, v. 164(5), pp. 649-660 (CEN Technical Journal, v. 8, n. 1, pp. 3750).
Lambert, A. and Hsü, K.J., 1979, Nonannual cycles of varve-like sedimentation in Walensee, Switzerland: Sedimentology, v. 26, pp. 453-461.
Oard, Michael J., 1992, VarvesThe First "Absolute" Chronology (Part I), Creation Research Society Quarterly, vol. 29. pp. 72-80.
Quigley, R.M., 1983, Glaciolacustrine and glacionarine clay deposition: a North American perspective. In N. Eyles, editor. Glacial Geologyan introduction for engineers and earth scientists. Pergamon Press. New York, pp. 140-167.
Smith, N.D., M.A. Venol and S.K. Kennedy, 1982, Comparisons of sedimentation regimes in four glacier-fed lakes of western Alberta. In Davidson-Arnott, R., W. Nickling and B.O. Fahey editors, Research in glacial, glaciofluvial, and glaciolacustrine systems. Geobooks, Norwich, pp. 203-238.
Stoner, D., 1994, Why the Earth is old, Science Speaks, v1.1, Schroeder Publishing for Jesus, Paramount, California.
Surdam, R.C. and Stanley, K.O., 1979, Lacustrine sedimentation during the culminating phase of Eocene Lake Gosiute, Wyoming (Green River Formation): Geological Society of America Bulletin, v. 90, pp. 93-110.
Wood, A.E., 1947, Multiple banding of sediments deposited during a single season. American Journal of Science 245:304-312.