Science in Christian Perspective
From: JASA, 2, 1(1950): 1-15.
The theory of deluge geology is summarized by H. W. Clark, The New Diluvialism, Science Publications, 1946, p. 205 as follows, "The pristine earth was destroyed by one great overwhelming catastrophe, the Flood, the Deluge, of Genesis 6, 7, and 8 and that this Flood was the direct or indirect cause of most of the major geological ,features of the earth." This statement is in complete disagreement with the conclusions of trained geologists the world over who believe various strata have been deposited over tremendous periods of time according to known physical and chemical laws. Since geology as a science is concerned with the history of the physical and biological earth, it deals with a subject important to a Christian view of the world. Although a large proportion of the geologists of the 19th century were at least nominal Christians and suggested means of harmonizing the science of geology with the Scriptures, the field was soon lost to the rising tide of secularism. In the early 1900's George McCready Price wrote the first of a stream of books and papers on "Flood Geology." Because this view gave apparent support to certain popular interpretations of Genesis, Price's writings received wide distribution in evangelical circles. Numerous would-be apologists who wrote for the Christian public such as Rimmer, Nelson, O'Toole, Hamilton and others assumed Price's Flood Geology to be sound science and a weapon against evolution. This theory has grown and infiltrated the greater portion of fundamental Christianity in America primarily due to the absence of trained Christian geologists.
It is the purpose of this paper to present selected fragments of the geological evidence in terms of the physical and chemical laws which apply to geological processes and materials. The greatest difficulty in accomplishing such a purpose is the adequate visualization of geologic features. To understand geology right ly one must visit the fields, the mountains and valleys, and the seasides armed with a reasonable preparation in physics and chemistry.
The most Complete account of flood geology by G. M. Price is to be found in his "The New Geology" 1923. (For 50 years the thesis has hardly been modified as in one of his latest, "Common-sense Geology" 1946.) In 1941 the Bulletin of Deluge Geology was started, edited by G. M. Price and C. B. Courville for further discussion and propagation of the thesis. This publication has apparently been replaced in 1946 by "The Forum" of which Volumes I and II comprising 130 pages over 19461948 have appeared.
Recently another point of view in flood geology has appeared in a book by Clark referred to previously. Clark differs considerably with Price in that he admits many of the accepted geological facts which Price denies. These admissions make flood geology even less tenable.
Training of the Exponents of Flood Geology
G. M. Price according to his brief autobiography in Vol. I, No. 4 of the Bull. of Flood Geology had two years at Battle Creek College in classics and theology.
Later he took a teachers training course at the Normal School in New Brunswick which included some elementary study in natural science. This ended his formal education.
The primary proponents of flood geology have been of 7th Day Adventist persuasion and have assumed from their theological tenets that a 6-10,000 year span is required for all life. Price writes in the above Bulletin, "From childhood I had always believed in the Flood and ... I had become convinced of what that book (Patriarchs and Prophets, Mrs. E. G. White 1890) teaches about the Flood as the cause of the chief geological changes." It is evident that he did not approach the subject without a preconceived pattern to which the data must conform.
The authors of the articles in the flood geology bulletins include two M.D.'s, one Ph.D. chemist who makes a number of incorrect statements on chemical principles, and the others who list no degrees. The other prominent writer on Flood geology is H. W. Clark who has a master's degree in biology. None of these men have done any geologic field work such as mapping or studying paleontological or structural sequences.
Basic Errors -
~ There are four basic errors in the flood geology writings which appear persistently:
(1) There it confusion that geology and evolution are synonomous. The evolutionist does claim support from geology, and geology generally predicates at least physical evolution but geology itself is the independent science of the rocks of the earth's crust, their properties, origin, and history. The basic principles which geologists have discovered about the earth's crust can be developed without recourse to fossils.
(2) It is assumed that life has been on the earth only a few thousand years, therefore-the flood must account for geological strata. A good example of this is the constant reference to the present as a "zoologically impoverished-world." There are certainly many more animal types represented in the whole fossil record than are living. The present world is only "zoologically improverished" if all these fossils lived at one time and were all destroyed by the flood. However if these lived in various times over 500 million years as seems to be the case, then the biological statistics of this era are little different from others. It is a case of assuming in a major premise that which is to be proved.
(3) The physical and chemical conditions under which rocks are formed and, later, under stress, folded are not understood. This accounts in part for the illusionary confidence of the sincere flood geologists.
(4) The historical perspective accounts for the continuation of basic error. Price first wrote before radio activity was applied to age measurement, before oil wells had penetrated over three miles of sedimentary strata and perforated certain parts of the sedimentary column like a sieve, before Hedberg's classic work on the conditions under which sedimentary rock will be formed, before Grigg's experiments on the plastic flow of rock under sufficient pressure and temperature, before M. King Hubbert's calculations defining the state of rocks while undergoing folding, and before extensive sampling and age measurement of the finely laminated, continuous, but very ancient deep sea sediments.
THE SCIENCE OF GEOLOGY
Like other fields of physical science, geology assumes that the world abou t us operates according to law-and order. Much has been written by Christians against "uniformitarianism" while actually we must believe in it. We believe God created the universe according to a blueprint and that it operates according to predetermined laws. While it is true that God may supersede any of these laws at any time, it is certainly not the normal course of events, nor is it perpetuated for any great length of time. Therefore in geology the present operation of erosion, transportation sedimentation and compaction is the key to those actions in the past. The geologist does not believe everything that has happened to the earth's crust in the past can be identically duplicated today. He does believe that the present is the key to the past and that the same physical chemical laws have applied to all phenomena of geology. This is accepted generally by Christians for other sciences and, should be extended in their thinking to the science of geology. Another viewpoint is represented by Prof. Monsma of Calvin College who distinguishes "creation" from "providence." He thinks we can accept the extrapolation into the past of most physical quantities as measured at present except time. Thus he would infer that phenomena such as radioactivity operated by different rules in the "creation" and have the present rules due to "providence." This view is considered unreasonable because it would require God to have changed hundreds or thousands of physical laws or situations all in different ways by different amounts to give a consistent appearance of great antiquity but actually all were created a short period of time ago. Thus radioactivity, the accumulation of the salt in the sea, the heat radiation from the earth, or the speed of light and the distance of stars, all indicate millions of years of earth history yet are all independent, depending for their observation on entirely different laws,and events. So it will be assumed the rules haven't changed and that they can be applied.
Physical Chemistry of Rocks
There are three major rock types, igneous, sedimentary, and metamorphic. The igneous rocks which are those formed by a cooling silicate melt, intrude and cut the other two types of rock. The most common igneous rocks are granite and basalt. Sedimentary rocks are made up of particles derived either from the erosion of previously existing rocks or by chemical or biological precipitation. The major types of sedimentary rocks are shale (mudstone), sandstone, conglomerate, and limestone. There are many minor varieties and combinations of these four. From shale through sandstone ' to conglomerate the difference is primarily in particle size. Either igneous or sedimentary rocks may, under sufficient temperature and pressure become changed into metamorphic rocks. If this change is carried far enough, fossils are destroyed and still further many of the characteristic sedimentary features are obscured.
Formation of Sedimentary rocks
I The first stage in the formation of sedimentary rock is either erosion by chemical or mechanical means of previously existing rock, or in the case of chemical sediments, of precipitation by some chemical agency. First consider the detrital rocks-shale, sandstone and conglomerate. Whether the material is derived from chemical decomposition or mechanical abrasion, the process is extremely slow. Consider granite tombstones. How much has been chemically decomposed in historic time?
After material is broken up by mechanical or chemical means it must be transported by wind, ice or water. It has been determined that for sand and gravel the size of the particle that a stream can carry varies with the sixth power of the velocity of the stream. Thus the larger particles are quickly segregated on the basis of speed of the carrying medium. Fine particles of colloidal dimensions are carried in suspension by sluggish rivers and are precipitated only upon entry to the ocean water rich in electrolyte. Far out from shore, over the continental shelves there is very little sediment. Over these areas rates of sedimentation are so slow that a few feet may represent several hundred thousand years of continuous deposition. (See papers by W.D. Urry in Bull. of the Geol. Society of Am. and Am. Journ. of Science). The sedimentary rocks of the earth's crust were not produced by such deep water sedimentation but rather along continental shelves and in great inland seas such as the present Gulf of Mexico and Hudson's Bay. Offshore, where detrital material is lacking, limestone may form if the sea is sufficiently shallow and warm. Some limestones consist largely of shells of organisms but the bulk of the limestone in the sedimentary strata is in large part chemical precipitate. It must be emphasized, contrary to statements by flood geologists, that practically every sedimentary rock type known can be shown in the process of formation today with or without fossils.
After obtaining the detrital material and transferring it to a place of deposition such as a river delta, how does this loose mud become rock? Hedberg's great work in Venezuela elucidated this process under typical conditions. (Am. Assoc. Pet. Geol. Bull, 10, p. 105 and later Am. Jour. Science (1936) p. 241.) He was able to study the gradual compaction of river mud into hard rock shale with oil well cores. The area he chose is well known geologically from the intensive drilling. No essential change in sedimentation type is observed for two miles vertically in this area. Hedberg demonstrated that loose sediment must have at least a mile of additional sediment piled on top of it to lithify it. A mile of water will not suffice because the rock forming process is one of squeezing out water. Additional work by other scientists has confirmed these findings and further shown that essentially similar thicknesses must be applied to limestone and sandstone. Here then is a quantitative measure of the rock forming process. When we see a sedimentary rock on the surface, it must of necessity have been at least a mile deep in the earth's crust at some time in its history. Therefore if we observe a great thickness of sedimentary rock such as along the Rocky Mt. Front which has been folded and eroded to yield a much younger conglomerate, it is known that rocks were already lithified before this erosional process for the second cycle and had been covered by at least a mile of additional material which has been eroded off. The time dimension is large for such a process.
In Price's writings, the statement is frequently made that the fossiliferous strata are relatively thin. For example in Vol. I No. 4 of the Deluge Bulletin, "Everyone knows that the fossiliferous strata are seldom more than a mile or so in total thickness - often only a few hundred feet and below them is granite or primitive rocks which contain no fossils." The "everyone" in this statement must not include geologists for it is well known that in the various geosynclines and basins of sedimentation there can be found up to 20,000 to 30,000 feet for each geologic period. (For the relations of the various geological periods to each other as they are mentioned in the discussion, see Table 1.) Strata in the northern coast of
Geological Time Table (as generally accepted)
Era Period Epoch Date
Quaternary Recent 1,000,000
Paleozoic Devonian 300,000,000
(Pre-Cambrian) Timiskamian 1,000,000,000
Gulf of Mexico have been demonstrated by oil wells and seismic methods. A simple calculation will show that were all of the soil and loose rock in the U. S. A. bulldozed into a basin the size of this Gulf Coast geosyncline, it would hardly be full. But this basin is only one of dozens throughout geologic time and this represents only the time from Cretaceous to the present. Table 2 shows the total thicknesses (maximum) of sedimentary rocks observed in the Frazer Geosynclinal belt, which trends from So. California to Alaska, for each geologic period. It should be obvious that no flood of short term duration could possibly account for these strata.
These great accumulations of seidiments occur due to the filling of subsiding basins called geocynclines. One of these geocynclines is commonly truncated by another at a later time. In any particular period the sequence of sediments in the geosyncline is normally (1) conglomerate, (2) sandstone, (3) shale, (4) limestone.
The origin of coal, when the evidence is understood, also precludes flood geology from being correct. Coal is found in every period of geologic time but is most abundant in Central North America and England during the Carboniferous. That coal results from the accumulation, compaction, and alteration of plant debris has been demonstrated without question. There are two theories of origin, one that the material accumulated in situ where the vegetation grew and fell, the other that the material was transported. Most all deposits can be shown to fall into the first type - certainly all those of large a real extent. Since it takes a hundred feet of loose vegetable matter to form one foot of coal it can be readily calculated that if all the vegetation were scraped from ten times the area of the midwest coal fields and compressed in this sedimentary basin it would only supply enough plant matter to make a few of the thirty significant coal horizons.
The evidence for the in situ origin of coal beds is voluminous but a few items will be presented to show the nature of the data. Further details can be obtained by examining the scientific literature on coal or referring to some standard work on the subject such as Coal, by E. S. Moore published by Wiley, 1940.
1. There are large accumulations of vegetal matter forming in swamps at the present time, some of which, as the Great Dismal Swamp of Virginia and North Carolina, or the many large swamp's of Sumatra, are on a scale approaching those which gave rise to coal seams of considerable extent.
2. The purity of the coal, its freedom from mineral matter suggests the collection of the vegetation in swamps rather than in deposits where it has been transported with other sediments.
3. Numerous tree trunks with their roots firmly embedded in the underlying clays occur in the coal seams and in some cases the rootlets pierce fragments of buried wood in the clays.
4. Old soils on which the trees grew lie beneath the seams in some places.
5. The arrangements of various portions of plants with respect to one another is not, as a rule, that of transported material.
6. The lenses of cannel in bituminous coal indicate patches of open water in swamps where spores would collect in great quantities rather than deposits forming part of an ordinary sedimentary formation.
Maximum thickness for various periods in the Frazer
Geoiynclinal Belt (So. California to Alaska)
Period Maximum Thickness
Cambrian 12,000 feet
Permian 15 000
total 160,000 feet or about 30 miles
Many minor features give the geologist important information on the origin of
certain strata. Example (1) Gravels deposited by streams are generally clearly
graded in texture and the pebbles are rounded in proportion to the distance from
their source. Glacial gravels on the other hand are poorly sorted and commonly
show parallel striations caused by being dragged over abrasive surfaces. These
markings are never found on water carried pebbles. (2) the peculiar rare and
heavy mineral aggregates may distinguish one source area from another for the detrital material used in making up the rock. (3) Glacial varved clay could occur
only under the unique physiochemical conditions of low electrolyte glacial melt
water which rushes into glacial lakes during the summer and is very quiet with an
ice cover during the winter which permits slow sedimentation of the colloidal
fraction. This has been demonstrated both in the laboratory and by sampling over
a period of years of present day glacial lakes. There is no question any longer
that glacial varves are annual. (4) Conglomerates are most interesting in that
they contain pebbles of sedimentary rock which has already become lithified and
which due to warping or folding has been exposed to erosional agencies. Conglomerates which rest on an angular unconformity generally show pebbles of all of the
underlying tilted beds.
Fossils occur sporadically in sedimentary rocks. Many thick formations contain no observable fossils while others are richly fossiliferous over large areas. This is due to the type of deposition and the nature of the life entombed. Along present shores the same variation may be observed. A recent three foot high wave cut bench cut in unconsolidated sand at Jones Beach, N. Y. gives a beautiful exposure of undisturbed shells in the sand awaiting further burial. The appearance is that of a fossiliferous sandstone. Off the Florida coast and around the Gulf, away from large deltas, fossiliferous lime muds are undergoing compaction into limestone. The end product will duplicate any fossiliferous limestone of the Ordovician system except for the fauna.
Much has been made of the geologist "reasoning in a circle." It is said that the geologists assume that evolution is true and thus dates the rocks primarily by the fossils that are in them. He simply makes the simpler fossils and the less complex, younger. This is a misrepresentation of the situation. While it is true that the geologist will tentatively label a rock as Cambrian because it contains certain distinctive fossils, he does not do it because he accepts evolution. He does it because hundreds of thousands of careful observations have shown that for large periods of time, or if you please, for thick sequences of rock, there has been a definite fossil sequence which is the same the world over. While gaps in the record occur locally, and these are expected of an unstable crust which with its buckling and doming allows sedimentation at one time and erosion at another, the sequence observed is always the same so long as undisturbed sedimentary strata are dealt with. .
The geologist has excellent evidence that during the past the earth's crust was not static but constantly changing. Such changes are still going on but at a very slow rate. The Scandanavian peninsula for example, is emerging from the water at a measurable rate. Similar observations have been made on many parts of the 'earth's crust. In the rock strata these broad warps or narrower intense welts are shown by basins or troughs of deposition where the sediments are much thicker than in immediately adjacent areas. Invariably after a certain period of deposition either a broad warp or compression folding brings these rocks to the surface where erosional agencies can act on them. Subsequently they are again depressed and the new sediments truncate the old at some angle. Such is called an angular unconformity (or nonconformity) and since it commonly involves first the planing off by erosion of the tilted strata prior to deposition of the next cycle (which in each case recall must be superseded by at least a mile of sediment) a considerable time, far more than that 9vailable to historians, must be admitted.
The Flood geologists attribute such folding to soft muds and sands produced by the deluge. Physically this is impossible. M. King Hubbert, Director of Geophysical Research for the Shell Oil Company contributed an excellent theoretical investigation on the matter of scale models. He showed-that in order for any laboratory attempt to reproduce earth conditions, it must keep all the dimensions of the model to scale. By using the known viscosities of solid rock at the temperatures and pressures of 5 to 10 miles in the earth's crust, it can be shown that the comparable scale model material for a laboratory compression experiment would have to be modeling clay or shoemakers wax. Experiments with these materials under controlled conditions have produced Appalachian type folding, and in general the type of deformation observed in rocks. If the sedimentary rocks were once unconsolidated debris at the same time and the entire muddy mass was subjected to compression stress the result would be a chaotic mixture of material. The laboratory model to scale would be observed by squeezing a rubber flask which contained a layered mixture of alcohol and water. It would simply mix and spill out as a more or less homogeneous mass. Nothing of the type of thing observed in folded rocks could be obtained.
Other objections to the compressed mud suggestion is that the shear and tension fracture patterns can only be interpreted in terms of essentially solid rock. Furthere if the deformation has gone very far, high temperature and pressure minerals take the place of those of sediments. Pressure and temperature gradients are sufficiently well known for the earth to know that these minerals can only be produced at considerable depth on a regional scale. Also most of these intense metamorphic minerals are anhydrous.
Griggs, in his various articles in the Bull. of the Geol. Soc. of Am. and elsewhere, further showed by laboratory experiment that if rocks such as granite and limestone were subjected to confining pressure and temperature equivalent to great depths, the rocks would deform plastically to give the type of material found in nature.
Thus, strata is first lithified at considerable depth. Subsequently, subject to greater depth plus compressional and tensional stresses, it is deformed to yield folded rock strata so commonly observed by the geologists in the areas of orogeny (folding).
Price has claimed repeatedly that recumbent folds or thrust faults have been invented by paleontologists simply to save face when the fossil sequence was reversed. He says "In all examples of this sort (reversal) which are now known from all parts of the world, the physical evidence of the strata gives no indication of anything abnormal." By "anything abnormal" he means folding or thrust faulting on 6,large scale''. To such an unwarranted assertion the person who wishes to evaluate the question must go map the rocks for himself. The fact is that such faults occur only in belts of obvious intense deformation which make up only a very small fraction of the sedimentary column. Commonly described areas are the Alps, Scottish Highlands, Appalachian-Taconic region, and the Canadian Rockies. Price always refers to a statement by McConnel of the Canadian Survey Report of 1886 on the Structure .of the Canadian Rockies which emphasizes the conformability of the pre-Cambrian limestone on top of the Cretaceous shale. Price then claims on this basis that thrust faulting is a fiction. The difficulty is that he has listed a small part of the quotation which gave clear evidence for such thrusting. A more complete quotation from the report follows:
"The fault plane here (in the Bow Valley) is nearly horizontal and that two formations, viewed from the valley, appear to succeed one another conformably. The Cretaceous shales are bent sharply toward the east in a number Qf places, but with this exception have suffered little by the sliding of the limestone over them, and their comparatively undisturbed condition seems hardly compatible with the extreme faulting which was necessary to bring them into their present position. They are, however, very soft, and doubtless owe their immunity to this fact. It is otherwise with the overlying limestones, which have been strongly corrugated in many places, and are often whitened and cracked in the vicinity of the fault plane, the cracks have been subsequently filled with calcite. Enclosed argillaceous beds have been turned into schists and the banded appearance of much of the limestone is, no doubt, due to the shearing caused by the thrust. The limestones west of the fault are often bent by their pressure against the beds on the eastern side into a succession of sharp folds and are occasionally completely overturned. They also show disturbances in the altered and cracked appearance of the strata in the immediate vicinity of the faulted line."
The mobility of such shale has been demonstrated in the laboratory. 70 years of additional detailed mapping in the Canadian Rockies has thoroughly confirmed the thrust faults - on physical not paleontologic grounds.
The Time Dimension
The time required for these processes to yield their results is obviously the most critical in the whole discussion. If the various rocks labelled Cambrian, Ordovician, Silurian and so on can be shown to have been formed at 500 million., 400 million, 350 million years ago respectively there could no longer be any argument about the flood doing the work 6000 years ago.
In geology there are numerous evidences of great antiquity. Some of these have already been mentioned. Relative ages are agreed on by all, flood geology writers included. The clear superposition of strata in underformed areas is sufficient. For absolute time, recourse must be made to other features. Qualitative indications can be made from rates of weathering, rates of mechanical erosion and sedimentation, the number of unconformities in a sequence indicating uplift and erosion, rates of deformation, rate loss of heat from the earth's surface, accumulation of salt in the sea, etc. In Yellowstone Park there is a stratigraphic section of 2000' exposed which shows 18 successive petrified forests. Each forest grew to maturity before it was wiped out with a lava flow. The lava had to be weathered into soil before the next forest could even start. Further, this is only a small section of the stratigraphic column in this area. It would be most difficult for flood geology to account for these facts. Price suggests that vulcanism is due to coal burning underground which is being formed from vegetable matter trapped during the flood. This would mean that hundreds of times the total world coal reserve must have been used in melting rock at depth to account for the prodigious thickness of volcanic rocks through the stratigraphic section. A chemist might inquire where the oxygen came from for the combustion.
There is an interesting unconformity bordering the San Joaquin Valley in California. The Pliocene Tulare formation was deposited on older sedimentary beds, later folded back on itself, then was eroded level so that Pleistocene sediments could be superimposed. After more than a mile of this material was laid down the whole area was tilted and eroded to give the present relationship. This is one more of the excellent qualitative evidences for the great antiquity of these formations.
One of the most convincing arguments of a qualitative nature of the antiquity of sedimentary strata is derived from a study of the gypsum and salt content of the stratai Great thicknesses of gypsum and salt occur in several places in North America such as the Silurian strata of Michigan or the Permian of West Texas and New Mexico. In the latter area the gypsum alone totals around 1500 feet in thickness. It is not continuous vertically but some of the pure gypsum beds may be several tens of feet thick. The beds have an areal extent of thousands of square miles and are underlain and overlain by fossiliferous sedimentary strata. Gypsum is.-formed by precipiation of the salt out of ocean water under intensely arid conditions.. The presence of large bodies of salt therefore means long time evaporation in restricted bodies of salt water with continual subsidence of the land. Since the evaporation of 1000. vertical feet of sea water yields only 0.7 foot of gypsum, it would take a body of water some 450 miles high to evaporate out the amount of gypsum found in the West Texas Permian basin. This can only mean continual influx of ocean water plus sustained evaporation. Such natural salt pans are numerous in coastal areas of arid regions. The Gulf of Karabugaz, on the eastern side of the Caspian Sea, is a well-known example of concentration of salt water behind a bar with a narrow shallow inlet. Here amid the surrounding deserts, evaporation is so rapid that a current flows continuously from the Caspian Sea into the Gulf augmenting the Gulf waters with some 350,000 tons of salt daily.
An idea of the rate of evaporation can be obtained from the Dean Sea where careful measurements show an evaporation of 10' of water per year. Since this is the fastest evaporation measured it will be applied to the West Texas case. Here about 5,000,000 feet of water must have been evaporated. This would require 500, 000 years as an absolute minimum. Recalling that these gypsum layers are intercalated, underlain and overlain with fossiliferous sedimentary rocks measuring up to four or five miles in total thickness, great spans of time are essential for any rational interpretation.
The only quantitative methods of getting absolute time are based on radioactive isotopes in the earth's crust. While much remains to be done in the refinement and development of technique, it is thoroughly established that approximate absolute dates may be put on rocks with as much theoretical justification as the weight of an object by a balance.
The method is very simple in principle. All radioactive atoms of a particular specie of an element disintegrate at a constant rate characteristic of that particular specie or isotope. This rate is unaffected by any temperature, pressure, electrical or magnetic fields, mass, impurity, or indeed anything that could be done to the atom under normal surface conditions. It can be calculated that these rates
do change as stellar temperatures of the order of millions of degrees are reached. But such temperatures the earth has never known since it was a separate body in the universe. The various geochemical processes in the earth's crust tend to separate one element from another, thus it is that uranium is found in the mineral uraninite or pitchblende while lead is found in galena. The uranium in the uraninite crystal so formed from ore solutions emanating from the depths of the earth's crust was disintegrating throughout its history at its constant rate but the lead being produced was constantly separated from it by these chemical processed at depth. The result is that when the uraninite crystal forms it is essentially free from lead and hence as it continues its constant disintegration lead accumulates. Thus when a geologist finds such a crystal and brings it back to the laboratory an analysis for uranium and lead coupled with a knowledge of the rate of production of lead gives him the age since the uranium crystal was formed. Since such crystals are found in ore bodies which crosscut other rocks, the other rocks must at least be older than this date. But what if the uranium crystal was in some way contaminated with some common lead from somewhere. This simply means a little more work. Ordinary-lead has a different isotopic composition from uranium lead and hence by mass spectrometer analysis the presence and percentage of ordinary lead can be measured. Actually on most uraninite specimens, four independent age measurements can be made. There are present the two uranium isotopes, U238 and U235 as well as thorium isotope 232. Each of these isotopes has a known long half life (the time for half of the material to disintegrate) and each yields its own specie of lead. Further, since the ratio of U238 to U235 is constant, but the rates of decay are different, the ratio of the lead produced from U235 to that produced from U238 changes in a known way with time. This is the fourth independent age measurement that can be made on the same specimen.
Hundreds of measurements of uranium-lead ratios have been made. In all cases the ages have been in agreement with the order already worked out by geologists on the basis of stratigraphy and structure. An idea of the precision of the method is shown in Table 3 which gives the measured ages of the Marealabian pegmatites of the Baltic shield in N. E. Karelia. The specimens come from four different pegmatites and were analyzed by three different chemists.
The uranium lead method has yielded ages of rocks from early pre-Cambrian to Pliocene.
Radioactive age determinations are not restricted to uranium-lead ratios. The heavy radioactive elements give off helium in the course of their series, decay to lead, and this is trapped in the crystal lattice. Thus a helium-uranium ratio should also give the age of the mineral. With helium, however, there is the possibility of leakage throughout geologic time. It has been shown that certain minerals such as magnetite retain their helium almost completely while others have known leakage rates. In general the helium age would be a minimum age. Two important conclusions come out of the helium work to date. (1) For a given rock type the relative ages of rock strata from all over the earth agree with the accepted geologic labels and show Paleozoic rocks to be of the order of hundreds of millions of years old. (2) The smaller number of very carefully measured specimens on minerals which retain their helium 100% are in complete agreement with uranium-lead ages. Again much work of refinement and of technique and the amassing of more date is going on but the method has been demonstrated to be valid by the hundreds of consistent results obtained.
In addition to these methods there are a number of others which are entirely independent but which give identical results. One of the most promising of the newer methods is the measurement of the rubidium 87 - strontium 87 ratio. Rubidium 87 decays to strontium 87 with a half life of about 5 x 1010 years hence can be used to date the older rocks. Ordinary strontium is dominantly strontium 88 and hence by mass spectrometer analysis the radiogenic (i.e. from rubidium) can be separated from common strontium. The amount of radiogenic strontium, of course, is alone used for the age ratio. Further, methods are being developed for the direct dating of sedimentary rocks.
A recent symposium on these methods published by the ASA gives details on the various methods and contains a bibliography of the more important scientific papers dealing with the subject. Anyone unconvinced of the validity of the radioactive method of dating should study these papers following the mastery of a book on the elements of radioactivity or nuclear physics.
Within five years most of the important stratigraphic sections will have been dated in absolute-time to an accuracy of 25% of the true age. The dates will range from the present back to earliest per-Cambrian (ca. 2,500,000,000)
Mechanisms of Flood Geology
G. M. Price suggests a shock from outside the earth (astronomical) which might cause great tidal waves sweeping twice daily around the earth from east to west at speeds up to 1000 m.p.h. at the equator. After the waters started receding climatic conditions would be so altered that for centuries there would be increased rainfall causing faster erosion than today. Further he assumes the clouded conditions produced cooling and glaciation. The alternative that Clark suggests is that the initial geography of the earth was that of a low broad flat area with low narrow seaways which are supposed to correspond to presently observed geosynclines of deposition. He appears to want less exciting conditions. He offers strong rising currents along narrow waterways to account for the stratified rocks. Since Clark admits of the universal fossil sequence he can use quieter water. He says the sequence is simply an ecological one with the animals that lived at lower altitudes being engulfed first.
All of the potent objections to flood geology presented previously apply to both of these views. There are a few additional facts which remain to be considered. Since the important sedimentary rock types are being formed today under observable conditions it is reasonable to assume that 1000 m.p.h. tidal waves would cause a very different result. Such a process would, it seems, continually mix and remix: in the most chaotic fashion the soft materials of the earth's outer surface. It would do relatively little to solid rock and certainly could not be called on to produce miles of thinly laminated colloidal sediments, nor is it reasonable to assume that the fossils would be unbroken lying in neat horizontal layers as is the usual case. The fact that deep sea caves show extremely slow unbroken sedimentation of a most delicate sort back hundreds of thousands of years by radioactivity measurements also precludes wildly rushing water. But then, if quieter water is assumed where is the detrital material to fill even a few of the great sedimentary basins? Why should most geocynclines show the sediments to coarsen to the uplifted side or sides showing clearly that the materials which fill the basin were eroded from the adjacent land mass and that solid rock was being eroded largely by chemical weathering which would play no part in a flood since it involves oxidation and the slow action of carbonated water on the insoluble silicates. If the fossiliferstrata are simply a reflection of ecological zones why are ocean and continental deposits constantly interlayered after the other throughout the geological column. All Tertiary rocks are certainly not continental.
Ages from Uraninite Specimens from Marealbian Pegmatites
Baltic Shield (Report of Comm. on Geol. Time 1946-1947 p. 43)
Apparent Age in 1760
Those that contain the mammals are continental--because mammals generally live on
land but there are deep water Tertiary deposits as well as deep water and shallow
water Cambrian deposits, The difference is that in the continential Tertiary deposits mammal bones are found whereas in continental Cambrian rocks no such are
found. Whether a rock
continental or marine in origin can be determined by the
mineralogy,independent of the fossils it contains.
Finally it might be of interest to observe the effect of large tidal waves, the tsunamis of the Pacific. During a tsunami the water often rises very much like a tide so that erosion which accompanies the wave may come largely from the rushing back of the water down the slope or from the ordinary wind waves which ride in on top of-the tsunamis and which are able to attack an area that has not been adjusted to wave attack and may, therefore, yield very rapidly. Sand dunes and earth embankments inside the beach may be greatly truncated but the beach outside this eroded area may show, little sign of change in profile. Many such cases were found in the Hawaian Islands after the tsunami of April 1, 1946. Two features claimed by flood geology are emphatically not observed even in miniature in tsunamis action. (1) Solid rock is not appreciably eroded. (2) Sedimentary deposits similar to that which could form rocks like those observed in the geological sequence are not formed.
1. The theory that a relatively recent universal flood can account for the sedimentary strata of the earth is entirely inadequate to explain the observed data in geology. The major propositions of the theory are contradicted by established physical and chemical laws.
2. The science of geology precludes certain interpretations of Genesis but does not make impossible acceptance of plenary inspiration of the scriptures.
3. This paper has been negative in character because it is believed that this unscientific theory of flood geology has done and will do considerable harm to the strong propagation of the gospel among educated people. On the positive side it is important for the Christian geologist to carefully study the truly superficial erosional and depositional effects on the earth to obtain evidence on the extent and nature of the flood of Noah.