RUSSIAN JOURNAL OF EARTH SCIENCES VOL. 9, ES1003, doi:10.2205/2007ES000222, 2007

Some Excerpts from the Work of N. A. Golovkinsky, 1868

[4]  In early April 1868, N. A. Golovkinsky submitted the manuscript of his doctoral thesis "The Permian Formation of the Central Kama-Volga Basin" [Golovkinsky, 1868] to the Department of Physics and Mathematics of Kazan University. This thesis was based on the materials acquired during the expeditions of 1866 and 1867.

[5]  In spring 1866, The Imperial Mineralogical Society of St. Petersburg invited N. A. Golovkinsky to take part in detailed geological studies in the territory of Russia. The Mineralogical Society provided N. Golovkinsky with funds to conduct geological observations in summer 1866 with the main focus on the Permian limestone formation in the Kazan and, partially, Vyatka provinces. Golovkinsky surveyed the areas between Elabuga and Chistopol and those between Tetyushi and Sviyazhsk. In summer 1867, the Permian formation was surveyed further to the east, up to the town of Malmyzha. In winter 1867-1868, these observations were generalised to form the aforementioned manuscript. The thesis was defended on 20 December 1868.

[6]  This work contains three chapters. The geological phenomena of the Permian basin are considered in the first chapter, main organic remains of the limestone formation in the second one, and the distribution of these remains in the third one [Golovkinsky, 1868; page 2]. (Here and below referred pages are related to the paper of Golovkinsky, [1868]).

[7]  The first two chapters are dedicated to the regional structure of the Permian formation and the layer-by-layer description of individual sections, folding, rock formation processes, secondary alteration of rocks (dolomitisation, gypsum formation, etc.) and palaeontological characteristics. Fundamental issues of strata formation are considered in the third chapter.

[8]  Golovkinsky wrote at the beginning of this chapter: "Let us now try to thoroughly investigate the meaning and causes of the distribution of organic remains in the Permian limestone formation described in the previous chapter" (Page 112).

2007ES000222-fig01
Figure 1
[9]  After analysing the distribution of organic remains, he developed a faunal zoning scheme (Figure 1), in which "a continuous layer of the shallow-water fauna envelops the deep-sea fauna" (Page 120).

[10]  It was later found that there was no lower conchiferous bed in this formation. (This stratum was initially identified by several observations near the village of Bogorodskoye but was later found to be the upper conchiferous bed). Nevertheless, Golovkinsky's concept that shallow-water environments are replaced by deep-water ones and then again by shallow-water ones has been proven to be principally true and solid. This proposition states that sedimentation is characterised by cyclicity. Golovkinsky further used this concept to build the first geological sedimentation model for the littoral environment (from this point on, the bold font was created by the authors of the present paper and the italics are according to Golovkinsky's original text). Golovkinsky built his model in the following way [Golovkinsky, 1868]:

[11]  "Let A (see Figure 1a) represent the rock mass composing the land and gradually plunging below the sea level oo prime. The coastal portion co prime accumulates materials delivered from the land, conglomerates, sandstones and clays; the open-sea portion ab contains limestone formed by mollusc shells; the bc portion contains deposited marl, an intermediate rock formed through the mixing of limestone with the littoral drift.

[12]  The subsidence of the basin's bottom and of the land should in some time produce new masses of limestone, marl and sandstone at the o 1 o 1prime level in a similar position (Figure 1b), but marl, corresponding to bc, is above sandstone co prime, and the limestone portion, corresponding to ab, above the marl portion bc and the sandstone portion coprime. As the level changed gradually, the rocks did not form any highs, as shown in Figure 1b, but were shaped as continuous layers as shown in Figure 1c that also depicts further stages of the same process. Let us assume that the subsidence of the bottom and the infilling of the basin took place gradually, and that the infilling rate was two thirds of the subsidence rate, as in the preceding figures. In this case, the depth of the left portion of the basin gradually increases to become four times higher at the level o3 o3prime than at the level ooprime. If the subsidence rate is then decreased and the basin infilling rate remains unchanged, the latter will finally be higher than the former will only change by o3 o4 during the period of time corresponding to that between level positions o3 and o2, o2 and o1, o1 and o (Figure 1d), and the mass of coastal rocks transferred to the basin will also remain unchanged. Therefore, without being deposited into the mass of the same thickness as before, it will gradually fill in the coastal shallow-water zone and will extend towards the centre of the basin to e (Figure 1d) to cover limestone... It can be assumed that the coastline will in this process be elevated to h. During a subsequent, slower change of the level to o5, marl and then sandstone will extend further towards the centre of the basin to f. Because of the continuity of the process, the stratification shall finally assume the shape shown in Figure 1e; (Pages 122-123).

[13]  "The previously assumed subsidence and basin infilling rates only affect secondary features of the geological lens (only half of which is currently considered) that is formed by this stratification, thickness of the strata, sharpness of their bends and other parameters, but the overall pattern generally remains unchanged. If the subsidence rate does not decrease and remains unchanged or increases, then only the lower portion of the lens is formed with the strata gently sloping from the coast; if the elevation precedes the subsidence, then the upper and lower parts in the resulting pattern swap places" (Page 124).

[14]  "The consequences of this process should be studied in full detail. Let us consider a formation consisting of the overlapping sandstone, marl and limestone strata as shown in Figure 1f. Conventionally, these strata are considered to have been deposited one after another during consecutive periods of time. However, if these strata represent only the lower, non-eroded portion of the geological lens, then this concept can only be valid in the limited area. Figure 1e shows that the lines that pass through simultaneously deposited portions of the formation, i.e. those showing the position of the bottom, intersect all the three strata, and the continuous tracing of any bed from left to right, - for instance, sandstone - brings us to another formation. This can lead to the following, apparently paradoxical, conclusion: the generally accepted concept that successive strata are formed consecutively is not true. The initial consideration of this conclusion and of strata belonging to different formations would naturally lead to the following serious objection: if the adjacent strata of sandstone, marl and limestone were formed from gradually deposited sediments, as shown in Figures 1a, 1b, and 1c, then the transition from one stratum to another would have to be gradual because there could of course be no sharp boundaries between the deposition zones of sandstone, marl and limestone (Page 125)."

[15]  Golovkinsky points out that the model proposed by him is a substantially simplified one:

[16]  "However, it should be remembered that the accuracy and simplicity of the strata shown in Figures 1c and 1e could only be imagined if the process that formed them were ideally simple; it would require that littoral sediments be distributed equidistantly from the coast and that the margin of the sand formation c (Figure 1a) be moved to the right by the same distance as the coastal point of the sea level o prime due to its lowering. In reality, such accuracy is impossible: under the influence of rainy and dry seasons with abundant and rapid or shallow and quiet rivers bringing various quantities of suspended or rolling material distributed over large or small areas and under the influence of storms and temporary flows littoral sediments constantly reshape their distribution zone, which extends into the open-sea limestone area during one period and regresses towards the coast during another. These processes make strata unevenly serrate; the dents, very sharp and long, are in the form of thin interlayers that alternate with rocks of the adjacent layer... (Page 126)."

[17]  In this context, Golovkinsky considers correlation of sedimentary formations in the following way: "A distinction should be made between chronological, stratigraphical, petrographical and palaeontological horizons. Generally, a geological horizon is a zone containing those portions of a formation that are similar in one of the above criteria. For instance, Figure 1c shows sandstone and marl strata that are single petrographical or stratigraphical horizons throughout their extent. However, these are not identical: the stratigraphical horizon of a pinched-out stratum continues further into the zone where its petrographical one does not exist..., so it is a palaeontological horizon that can be not only different from the above one but also not parallel to the petrographical horizon...

[18]  The above relation of a petrographical horizon to a chronological one is also fully applicable to palaeontological horizons. All faunas with a lens-like distribution at various depths within the formation existed at the same time; these represent different facies of a given geological period, which depended on depth and gradually moved due to sea-bottom movements. Figure 1e shows the general trend of their movement. To study this trend in more detail, some additional data should be taken into consideration. The works of Forbes and other researchers demonstrate that the distribution of marine organisms depends, apart from the depth, on many other factors, including the mineral nature of the bottom that will be considered here. Both the deep-sea facies and shallow-water facies are subdivided into sandy, silty, rocky and other facies, each characterized by its specific forms...

[19] ... The study of gradual changes of the forms in time is possible through tracing the faunas' movement." (Pages 127-129).

[20]  "... The apparent lack of transitional form in the vertical direction indicates nothing but insufficient attention to the known facts on the distribution of recent marine organisms and on its strong dependence on the complex combination of external conditions.... If transitional forms really existed in time, these should be horizontally traced within geological formations, along the strike of palaeontological horizons, but not in a perpendicular direction, according to conventional practice." (Page 131).

[21]  "If geological parallelism means isochronism, then parallelization (correlation) should be based on facies. As expected, the vertical succession of forms in one country may totally disagree with that in another, which may be puzzling to researchers. And the conventional practice of chronological parallelization suggests that the strata under study should be correlated with other strata of previously studied basins formed at the same time. This can be done in a very simple way: focusing attention on those forms that occur in a desired succession and rejecting the others as insignificant, local exceptions. Moreover, geologists use coincidental occurrences of fossils as a convincing proof of the simultaneous formation of strata." (Page 133).

[22]  "... Some formations appeared in different times but within one geological period with the unchanged fauna, and these formations are nothing but facies. There is nothing puzzling in their similar successions, just as in recurring successions of seasons; similarly to the transition from winter to summer through spring, the transition from littoral, sandy deposits to purely marine limestone is implemented through clay and marl and through the deep-sea fauna" (Page 134).

[23]  "Numerous books claim that geological science is complete with perfect principles, and one only has to accommodate some new facts in the ready-made framework. Unfortunately, this is the illusion that has nothing to do with the reality.

[24]  Formations are usually correlated layer by layer as if this method is simple and perfect as an axiom. However, a closer look at this concept makes it clear that this is not an axiom but a relic of half-poetic, half-ignorant and outdated ideas that the outer portion of the earth consists of continuous, concentric, homogeneous layers. These ideas were amended and published on behalf of d'Orbigny to find numerous supporters due to their clearness and plainness. However, new studies revealed new facts that the concept of the co-existence and simultaneous disappearance of omnipresent faunas is incorrect. The theory of facies and gradual changes of the biotic population steadily progressed, and no geologists, even the most enthusiastic supporters of parallelism, are likely today to discard the existence of the same forms in various times and of different forms at the same time in various localities. Notwithstanding that the above obsolete principle is confronted by the obvious reality, it is largely obeyed through habits and inertia." (Page 135-136).

[25]  In the authors' view, these excerpts from Golovkinsky's work most vividly demonstrate his understanding of the facies law and of the infilling of basins with sediments as well as the architecture (geometry) of the strata that are formed in the process. Unfortunately, the authors cannot quote any more fragments of this remarkable paper for space considerations and have to refer readers to the original.


RJES

Citation: Nurgalieva, N. G., V. M. Vinokurov, and D. K. Nurgaliev (2007), The Golovkinsky strata formation model, basic facies law and sequence stratigraphy concept: Historical sources and relations, Russ. J. Earth Sci., 9, ES1003, doi:10.2205/2007ES000222.

Copyright 2007 by the Russian Journal of Earth Sciences

Powered by TeXWeb (Win32, v.2.0).