PRELIMINARY REPORT

on a student excursion along the Tom River

in 1909.

In the summer of 1909, by instruction of the Council of the Tomsk Technological Institute, I undertook a geological excursion along the Tom River from the city of Kuznetsk to the city of Tomsk.

Taking part in this excursion were also students of the Mining Department: I. E. Devyashin, Ya. T. Kalnin, N. P. Pavlov, and K. T. Tyumentsev, for whom, having chosen the geological-prospecting specialty, it was necessary to complete geological practice.

The task of the excursion was to examine the banks of the Tom River, which in the indicated area present a mass of excellent sections, making it possible to become acquainted with the geological structure of the locality, and also allowing the collection of abundant paleontological material, often in very good preservation.

Along the indicated stretch, the Tom River flows chiefly within the so-called Kuznetsk coal-bearing basin, and therefore the attention of the excursion was concentrated mainly on the Carboniferous deposits. But, in addition to this, no small attention was paid to other sedimentary rocks exposed in the valley of the Tom River, such as Devonian and post-Pliocene rocks, as well as to igneous rocks.

For a more complete acquaintance with the geological structure of the Kuznetsk basin, it was necessary to begin the examination of the bank sections not from the city of Kuznetsk, but from the mouth of the Belsa River, a right tributary of the Tom, since here lies the eastern boundary of the Kuznetsk basin. For this purpose it was necessary to go up to the indicated point by poles in special boats. In addition, part of the excursion participants (I, Tyumentsev, and Pavlov) went by poles up the right tributary of the Tom—the N. Ters—to the so-called Prokopyevsky Spring, which flows into the N. Ters from the right. The purpose of this small excursion was to examine the outcrops of melaphyres and to collect the various minerals occurring in them in the form of segregations, including zeolites, first indicated for this locality by Privatdozent of Tomsk University P. P. Pilipenko.

The excursion participants left Tomsk for Kuznetsk on the steamer of the commodity office of Vtorov, the Vasilii, in the first days of June. On June 8 they set out from Kuznetsk upstream in two pole-boats and ascended approximately 80 versts. Having then returned to the town of Kuznetsk in the same boats and made the necessary purchases, the members of the excursion, on June 16, moved downstream along the Tom. This time the excursion had at its disposal two boats: one large one, the so-called karbas, in which all the necessary provisions and items of equipment were kept, as well as the collected material, and another small boat, one of those in which they had ascended the Tom above Kuznetsk; this boat served for lighter and faster crossings. The excursion from Kuznetsk to Tomsk took 20 days, and on July 6 the participants arrived in the city of Tomsk.

Active assistance in outfitting the excursion was rendered by S. A. Maleshevskii, a feldsher living in Kuznetsk, who was kind enough to find in the town of Kuznetsk the boat needed for the excursion, and also pointed out a reliable and knowledgeable man, who was hired by us and sailed with us to Tomsk as helmsman. I take this opportunity to express here my gratitude to Mr. Maleshevskii for his assistance to the excursion.

During the excursion, not only geological and paleontological material was collected, but also a small amount of zoological material. In addition, the excursion had at its disposal two photographic cameras, thanks to which it was possible to obtain an entire series of excellent photographs, taken by the experienced hand of one of the excursion participants, K. G. Tyumentsеv. He also made measurements of air pressure and temperature.

In the present report I intend to give only a general outline of the geological observations made by the excursion and to present some new data concerning the geological structure of the locality touched upon by our observations, leaving a detailed description of various interesting points until the material we collected has been fully determined.

The valley of the Tom River, within the limits between the mouth of the Belsa River and the city of Tomsk, crosses, as has already been indicated, the so-called Kuznetsk Basin. This locality has more than once been the subject of geological observations. We see not only a whole series of investigators who incidentally touched upon the geological structure of the banks of the Tom, but also a considerable number of persons who specially and systematically studied the valley of the Tom River in geological terms. I shall not give here a detailed list of the investigators who have visited the locality of interest to us. I shall only point out that in recent times special attention has been devoted to the study of the geological structure of the Kuznetsk Basin by a number of geologists working from the Geological Section of the Cabinet of His Imperial Majesty. Among them we see Derzhavin, who even earlier, when serv—

lived at Tomsk University, followed the same route that we did, and printed a report on his investigations in the Proceedings of Tomsk University¹; of Venyukov², Polienov³, Tolmachev⁴, and Petz⁵, who clarified, in greater or lesser detail, the picture of the geological structure of the Kuznetsk Basin and, in particular, gave a systematic description of sections in various parts of the Tom valley within the above-mentioned limits.

The indications of these persons formed precisely the principal basis of our investigations, and, thanks to this, the tasks of our excursion were considerably facilitated. We had exact indications of various interesting points where we could, in advance, expect to find abundant material; we had only to concern ourselves with clarifying the details of the structure and with collecting, chiefly, paleontological material. But alongside this we also managed to encounter new facts, about which it will be necessary to speak separately and in greater detail. Before dwelling on our observations, it is necessary, in the most general outline, to touch upon the orography and geological structure of the locality that served as the object of our observations.

As can already be seen from the map of Tomsk Province, the Tom River, from the mouth of the Belsa River, flows at first in a latitudinal direction (from E to W), and then, a little below the town of Kuznetsk, sharply changes its direction to a meridional one and thus flows as far as the city of Tomsk.

Over this stretch it flows through localities of a comparatively uniform orographic character; here it flows chiefly through the Kuznetsk depression. The latter is a lowered steppe plain, bounded on the west by the Salair Ridge, and on the east by the spurs of the Alatau.

This plain descends from the east and from the west toward the middle part, where the Tom River flows. The monotony of the level expanse of this locality is disturbed only by the Karakan Ridge and the so-called melaphyre horseshoe; the latter consists of the Saltymakovo Ridge and of the Abinsk or Naryk mountains, running from the village of Kyrganskaya toward the Tom valley from the west and continuing on the right bank of the Tom in the form of the so-called Babii Kamen, which in turn forms the beginning of the so-called Kailot mountains; all these elevations stand out rather sharply above the surrounding locality. It should also be noted that small elevations, likewise consisting of melaphyre, are observed somewhat farther north—near the Taidon River. It is necessary

It is also necessary to note the hilly belt which, according to Polunov, runs along the eastern edge of the Salair Ridge. The remaining space of the Kuznetsk Basin is, as has been said, a more or less level locality. The latter is dissected by the valleys of the Tom River and of the tributaries flowing into it into a series of more or less noticeable ridges or “grivy,” forming watersheds between the rivers, as well as so-called “shelomy” (see Venukov). The grivy usually extend over a fairly considerable area, following the bends of the rivers, and, in Venukov’s opinion¹, constitute a characteristic feature of this locality. Polunov² also points to the existence of interfluve ridges, especially with respect to the left tributaries of the Tom River.

According to the indications of the same author³, “the elevation of various points of the Kuznetsk Basin does not show significant fluctuations. In general, outside the river valleys it varies around 300–325 meters, rising at the foot of the escarpment of the Salair Ridge to 350 meters and descending in the valleys of the Tom and Kondoma to 280–240 meters. The height of individual hills along the eastern margin of the Salair Ridge is not less than 400 meters.” The height of the ridges above the river level, according to Venukov⁴, reaches 40, 50, and even 60 sazhens (from 80–120 meters); the height of the shelomy is from 10 to 20, rarely more, sazhens above the surrounding locality.

As Venukov⁵ and Polunov⁶ quite rightly indicate, the relief of the Kuznetsk Basin is determined mainly by prolonged denudation, and only in exceptional cases does tectonics make itself felt in it. Polunov attributes, to a significant degree, a denudational character even to those elevations which extend parallel to the escarpment of the Salair Ridge. Only on the elevations forming part of the “melaphyre horseshoe” is the influence of tectonics visible.

That processes of erosion played an enormous role in this locality is evident at least from the fact that wherever the occurrence of post-Pliocene deposits upon coal-bearing deposits can be observed, one can observe an unconformable overlap of the former upon the latter; moreover, it is apparent that a considerable thickness of coal-bearing strata, gathered into various kinds of folds, has been carried away, and, if one were mentally to restore these folds, it would be necessary to add to their eroded parts very substantial portions (anticlines and saddles). That tectonics has no effect on the structure is also evident from the fact that we often observe a level

space there, where the bedrock has been strongly disturbed and the tectonics are very complex. Processes of erosion, of course, may have played a large role, since they acted over a prolonged period, beginning at the end of the Carboniferous period and continuing up to the post-Pliocene; in this locality, rocks intermediate in age between the Carboniferous and the post-Pliocene are unknown. Of course, the varying geological composition of the different parts of the locality did not fail to influence the character of erosion and, indirectly, the relief. For example, limestones are less susceptible to erosion than sands or clays. Limestone outcrops often have the appearance of high cliffs. Such cliffs we see, for instance, near the village of Pozharishcheva, where Devonian limestones crop out, or near the village of Mozzhukha, where Lower Carboniferous limestones are exposed.

Now it is necessary to dwell in greater detail on the valley of the Tom River. The direction of the Tom’s course is rather curious. It cannot be stated with complete precision what causes produced, in each instance, one or another deviation in the course of the Tom, but in general it must be said that the direction of the Tom’s course was influenced not only by factors of orographic and tectonic character. A striking example of this may be the sharp change in the Tom’s course immediately below Kuznetsk, after the Kondoma River flows into the Tom. Before the latter’s confluence, the Tom flows from east to west; after the confluence it changes its direction to a meridional one. In Polȳnov’s opinion¹, the valley of the Tom below Kuznetsk is a continuation of the valley of the Kondoma River. The latter, in Polȳnov’s opinion, in ancient times had worked out the channel along which the Tom later directed its waters; in other words, the Tom made use, as it were, of an already prepared channel. The valley of the Tom from the Belsy River to Tomsk has, of course, a very varied appearance. Closer to the headwaters it is narrow and has the character of a gorge. But then, especially after the Kondoma River flows into it, it widens considerably, and thus flows for almost its entire length to Tomsk. Only in the region of the Naryk Mountains and especially of the Saltymak Range does it narrow considerably, and here again we see gorges with steep banks.

The width of the Tom valley in the sections studied by Polȳnov², as the latter indicates, “is in general fairly uniform, and only to the north, at the place where the river cuts through the melaphyre ridge at Baby Kamen, does it narrow considerably, as it also does farther north at the breach through the Saltymak Range. The depth of the valley in relation to

the adjoining plateau, as barometric measurements have shown, is 60–70 meters.”

According to Venyukov¹, in sections more northerly than those investigated by Polinov, the Tom is not wide, and in summer, at low water, the width of the river usually does not exceed 200–300 sazhens, rarely more; only where there are islands in midstream does the width of its channel reach as much as a verst. Its course is confined by both banks, of which the right bank almost throughout consists of an uninterrupted series of high, precipitous hills, formed now of coal-bearing, now of Devonian rocks; the left bank is more low-lying, with rare bluffs of bedrock, and is formed for the most part by ancient river deposits or by loess-like yellow loam. Polinov also points to the more elevated right bank of the Tom at various points in the Tom valley.

The width of the valley of the Tom River reaches 6–7 versts. The velocity of the current of the Tom varies greatly. In the upper reaches it is, of course, considerable. There one can often distinguish small waterfalls—rapids—over which the river flows turbulently. The river deposits are represented by gravel. Lower down, on the contrary, finer river sediments—sand and clays—are seen more often, although gravel is observed almost as far as Tomsk itself, which depends on the unequal velocity in different parts of the Tom’s course. I shall not dwell on the tributaries of the Tom; those interested in them may find their description in the authors indicated. I shall pause only briefly on the N. Ters. This tributary flows through wild taiga country. Only in its lower reaches are there significant alluvial deposits, and the current there is weak. Higher up, however, this little river has a purely mountainous character and is distinguished by numerous riffles with a turbulent current.

Where the river widens, there are islands. These islands are composed in most cases of gravel, lying below, and of finer material—sandy-clayey in the upper parts—and are covered with dense vegetation.

The force of the current is not the same at different seasons of the year. In spring the current is much stronger and causes the transport of significant blocks of frozen ice. This same ice, together with the large stones frozen into it, produces the characteristic smoothing of the scarps approaching the very channel from either bank, and the formation on them of grooves and scratches running parallel to the course of the Tom. Both Venyukov¹ and Polinov dwell on this circumstance. The former indicates that rounding is observed most sharply on clay shales, then on limestones, partly on sandstones, and, among these, on sandstones interbedded with clay shales—

... it appears that the principal process is rather destruction, uneven weathering, and collapse, than the polishing and rounding of the cliffs.

There are no floodplains or inundated meadows along the banks of the Tom whatsoever, as the same author says. Therefore there is no strong spring flood, says the same author (p. 15). Therefore, there is no strong spring flood, but the water rises considerably, according to his indications, by 2, sometimes by 3 sazhen; the boundary is sharply expressed by a band of dark coloration and by a particular rounding of the lower parts of the bluffs¹; under such conditions the force of the current is concentrated almost in the same narrow channel through which the river flows at low water. It is not surprising that, thanks to this, such enormous blocks may be carried away as are often visible on the towpath in various places on the Tom. As Vennokov indicates, blocks are carried 100–200 versts, and sometimes more, from their original location. Such blocks, brought from afar, were also observed by us. Thus, for example, on the towpath of the left bank of the Tom below the mouth of the Osinovaya River we saw a large block of conglomerate up to 1 sazhen long and up to 2 arshins across, which had evidently been brought here by spring ice. Blocks likewise brought from afar were observed by us beyond Atkarinskaya, on the right bank of the Tom. Here there are blocks of sandstone with well-preserved plant impressions. The proof that they were brought lies in the fact that there are no such rocks nearby. Finally, a large block of limestone was observed opposite the village of Popovaya on the right bank of the Tom—it, too, was evidently brought by spring ice.

The locality through which the Tom flows differs in its vegetation cover in its different parts. The southern part and the south-western part represent steppe terrain, whereas the eastern and north-eastern parts are covered with taiga. The latter either comes directly up to the Tom River, or else is separated from the settlements by more or less considerable empty spaces, where the Tom valley widens, and in part, perhaps, the taiga has already been cleared for ploughlands, since in such places the population is denser.

Vennokov, who studied the more northern parts of the Kuznetsk basin, even says directly that this region is divided by the course of the Tom River into two almost equal parts: one—the south-western part—represents an agricultural region (it is the most populated), the other—the north-eastern, beyond-the-Tom part—is covered with taiga². As he indicates, little forest remains, and even that is concentrated chiefly in the river valleys, only occasionally emerging onto elevated places and covering ridges and summits.

The locality situated farther south, closer to Kuznetsk, likewise represents open space, often occupied by crops. Here, as

notes Polÿnov, we have a steppe plain¹. Here, too, the rivers flowing into the Tom from the left have a typical steppe character²—with disproportionately wide, rather weakly incised valleys, with a swampy floor and gently sloping valley sides; the tributaries of these rivers have the character of steppe gullies.

In many places lush herbaceous vegetation is visible. In some places this vegetation presents an astonishing “abundance of grasses.” The population is not uniform. Already on the map one can see that the more populated areas are either near the town of Kuznetsk or, especially closer to Tomsk; meanwhile, for example, in the area of the so-called melaphyre horseshoe there are almost no populated places at all. This is due, of course, partly also to the geological character of the locality. In those places where the banks of the Tom River are steep and wooded, large villages naturally could not develop, and there are only so-called zaimki or apiaries. The villages are confined mainly to the second terrace, composed of post-Pliocene loess-like clay, and they press mainly toward the Tom. Likewise, large villages are found on the left tributaries of the Tom, whereas on the right tributaries, which flow for the most part through wooded country, there are no large villages. For example, the valley of the N. Ters River presents an almost wild appearance; on it there are only zaimki and apiaries.

Geological Description of the Valley of the Tom River

As has already been indicated, the Tom, on its course from the mouth of the Belsa to Tomsk, flows among Devonian, Carboniferous, post-Pliocene, and ancient and modern alluvial deposits; in addition, along this route eruptive rocks crop out in several places.

These rocks, in general, are arranged as follows in the Tom valley: the Devonian and Carboniferous deposits, as well as the eruptive rocks, form the upper or oldest terrace of the Tom; the post-Pliocene deposits compose the second, or supra-meadow, terrace; and, finally, the ancient and modern river formations enter into the composition of the third, or meadow, terrace.

The three terraces mentioned can be observed in many places along the Tom River. Indications of their existence are given also by earlier authors, and our excursion likewise was able repeatedly to convince itself of their existence. These terraces can be observed especially well in those places where the Tom valley widens and significant

areas of post-Pliocene deposits. But in many places it may be seen that certain terraces are absent. This is the case when the Tom, having eroded the newer terraces, has approached the very oldest one. Or it may also be that new terraces could not have formed because of special orographic conditions—when, for example, the Tom had to force its way among hard rocks—there its long-continued activity could find expression almost exclusively in the formation of comparatively narrow gorges.

Sedimentary Rocks.

Devonian rocks.

Devonian deposits are represented by rather varied rocks and belong to two divisions—the middle and the upper. These sediments are developed unevenly in the Tom valley. Above the town of Kuznetsk they occur only above the Bel’sa River, where they form a narrow belt extending approximately in a meridional direction and bounding on the east the area of distribution there of Lower Carboniferous limestones. Here, on both the right and left banks of the Tom, there crops out a red marly limestone without fossils, which on the geological map published by the Geological Section of the Cabinet of H. I. M. is assigned to the Upper Devonian. Tolmachev ¹) assigns in the indicated region to the Upper Devonian red tuffaceous arkose sandstones, in places passing into conglomerates, with red limestones overlying them, connected in turn with calcareous sandstones overlying them. This geologist indicates here a complete section of Upper Devonian rocks with Lower Carboniferous rocks overlying them.

Below the indicated outcrops, the bedrock on the Tom River over a considerable distance is represented by Carboniferous sediments; only to the north of the melaphyre horseshoe do we again meet Upper Devonian deposits. Namely, on the left bank of the Tom above the mouth of its right tributary—the Taidon, almost opposite Simonova Zaimka, somewhat below Natal’in Island, an interesting section of Devonian sediments is visible. (Point No. 76 of our diary.) Fossils from this section were first collected by Derzhavin ²). Chernyshev, from the material delivered by the latter, determined the following forms: Spirif. Archiaci Murch., Sp. disjunctus Sow., Athyris phalaena Phill., Cyrtina heteroclyta Defr., Atrypa reticularis Lin. Strophomena Dutertrei Murch., Str. asella Vern.

Polynov ³) dwells in greater detail on this section, indicating that at this place there is a continuous sec—

¹) Tolmachev. Proceedings of the Geological Section of the Cabinet of H. I. M., vol. VI, pp. 422–423.
²) Derzhavin. Geological section of the banks of the Tom River, p. 53, and report on the geological excursion on the Tom River, p. 40.
³) Polynov. Proceedings of the Geological Section of the Cabinet of H. I. M., vol. III, pp. 175 and 253–254.

a cut through violet-red, thin-bedded, hard sandstones with a strike of NW 30°, dip 10° SW, which downstream are interbedded with green sandy loose rocks, in turn replaced farther below by coffee-brown and then light-brown sandstones and loose rocks; still lower, as Polnov points out, within this sequence there occur interbeds of light-yellow clayey limestone, in one of which Derzhavin found fossils. We recorded a fairly detailed section, in which we managed to collect a great many fossils. The processing of this material may constitute a rewarding subject for work. Besides many representatives of brachiopods, numerous corals were found here, which in some cases form reefs; two such beds were found here. Among these corals, representatives of the genus Cyathophyllum play a large role. Likewise, we were able to convince ourselves that the Devonian deposits here are represented by very diverse rocks. They consist of a series of alternating sandy clays, sandstones, partly conglomerates, marls, and marly limestones. The coloration of the rocks is variegated, but dark-reddish shades predominate. Fossils are confined chiefly to the limestone interbeds. The latter are grayish in color, with a fine-crystalline structure.

These Devonian rocks here rest upon a volcanic breccia, which in turn borders on porphyries and porphyrites that compose the core of the anticline indicated here by Derzhavin¹. The Devonian sediments just mentioned constitute the southwestern limb of this anticline. The continuation of the porphyry core of the anticline is visible below the mouth of the Taidon on the right bank of the Tom. Still farther downstream along the Tom, on the same right bank, Devonian sediments are visible, analogous to those just indicated and represented chiefly by dark-red conglomerates with very large pebbles. A little farther down, on the same right bank, a limestone interbed was found with the same fossils as above. These rocks constitute the northeastern limb of the same anticline. Polnov² states that the conglomerates emerge from beneath the orthoclase porphyries and their tuffs, but our observations did not confirm this. Rather, it must be thought that the conglomerates rest upon the porphyries.

A much more significant area of Devonian distribution appears near the village of Podonina and can perhaps be traced for a considerable distance along the banks of the Tom. Some localities with fossils, indicated by Derzhavin and Venyukov, were not found by us in this region, but instead new localities were found where there occur

fossils. Thus, in addition to the Devonian limestones with fossils already known in the literature, which crop out on the right bank above Pozharishcheva, we found Devonian fossils on the left bank below the same village, where alternating beds of limestone and light greenish shale are exposed. The limestone is bedded and strongly crumpled. Interbeds occur here in which the fossils are cemented by a clayey cement. The dip of the beds is approximately to the W. In the beds exposed upstream, corals occur: Favosites cervicornis, together with Spir. Archiaci and Sp. Chechiel; in the beds exposed downstream, Spir. Archiaci and Sp. Chechiel occur in abundance; in addition, Atrypa reticularis, Streptorhynchus umbraculum, Strophomena interstrialis, Martinia glabra, Rhynchonella, Bronteus, and others were found.

Farther downstream, on the same bank, greenish clayey shales are visible, among which there is an interbed of white fine-crystalline limestone, crowded with corals that here form a reef. The strike of the rocks is to the NE, while the dip varies—either to the NW or to the SE, which proves that the Devonian deposits here form a series of folds. In the shales one also observes a false cleavage running across the bedding planes. On them, incidentally, the action of the spring ice is clearly visible.

Farther along the Tom we did not find fossils; for a considerable distance greenish clayey shales crop out here, partly interbedded with grayish sandstones. But, taking into account that Derzhavin found Devonian fossils on the right bank of the Tom, considerably lower down, between Taimenskaya and the village of Ust-Iskitim (Spirifer Wihtneyi Hall, Sp. Archiaci Murch, Spirif. disjunctus Sow., Productella sp.), it must be supposed that the indicated shales belong to the Devonian. Farther from Ust-Iskitim to Kulakovo the banks of the Tom were examined by Petz¹, who considers the clayey shales exposed along the Tom between Ust-Iskitim and the village of Kulakovo to be Devonian. But in fact the picture here is different, and the area of distribution of the Devonian should be shown as much smaller than is done on the geological map of the Altai District published by the Cabinet of His Imperial Majesty. On this map, beginning from the Polomoshnaya station along the right bank of the Tom to the village of Spasskoye, a continuous development of the Middle Devonian is shown. This was evidently done on the basis of Petz’s supposition, who on p. 170 of his article (l. c.) says: “it is easier to suppose that the Tom shales will be somewhat older than the typical Upper Devonian ones and will perhaps constitute the upper horizons of the middle division of the same system.”

But, as it turns out, this is not entirely correct, since some of these shales must be assigned to the Carboniferous system. It may be supposed that the reason for this was an insufficiently detailed acquaintance with the bank sections of the Tom River below Polomoshnaia and the external similarity in petrographic composition of the argillaceous shales occurring here with the undoubted Devonian argillaceous shales developed higher up the Tom, as well as the stratigraphic data. Meanwhile, fossils alone could finally decide the question of the age of these rocks. In any case it is beyond doubt that, beginning with the village of Kulakovo, in the bank sections of the Tom River there occur deposits which should rather be recognized as Carboniferous. Near this village, in gray argillaceous shales, there are limestone lenses in which remains of cephalopods occur: Nautilus, Orthoceras (many), Productus, Chonetes, Orthis resupinata, Spirifer, Athyris, crinoid joints, Chaetetes, and others. The fossils are badly distorted, which makes them difficult to determine, but in general their character is more Carboniferous than Devonian. Still more certainly at another point, namely above the village of Yarskaia, half a verst below the mouth of the Shumikha brook, we have genuinely Carboniferous sediments; here, in dark-gray argillaceous shales, rather numerous Lower Carboniferous forms were found. In an argillaceous interbed on a small rocky peninsula the following are especially common: Syringothyris cuspidata, Spiriferina imbricata n. sp., Athyris, Productus semireticulatus, and others. The shales exposed here dip to the NE 56° at an angle of 12°. Taking also into account that farther along the Tom the same dark-gray argillaceous shales are developed as far as Tomsk, where Carboniferous fossils again occur,^1 it is necessary to conclude that the bedrock exposed along the right bank of the Tom, beginning with the village of Kulakovo and as far as the city of Tomsk, belongs to the Carboniferous system. At the same time, this confirms Derzhavin’s view,^2 which recognized a Carboniferous age for the thickness of argillaceous shales, and refutes the view of Petz^3 and Krasnopolsky,^4 who assigned a Devonian age to these shales.

Thus, the area of Devonian development on the map of the Altai District must in any case be pushed back to Kulakovo, or perhaps

^1 See Zaitsev. Proceedings of the Tomsk Society of Naturalists, I, 1889.
Derzhavin. “The bank of the Tom near Lagernoe,” Bulletin of Gold Mining, II, Nos. 17, 18, 1894. By the same author. “Geological investigations in Tomsk Province.” 1893. Mining Journal, 1896, p. 46.
Yanishevsky. “A note on the argillaceous shales near Tomsk,” Appendix to the minutes of the meeting of the K. Society of Naturalists, No. 220.

^2 Ibidem, p. 41.

^3 Ibidem, p. 170.

^4 Krasnopolsky, Geological investigations and searches for hard coal in the Mariinsk and Tomsk Districts in 1896 and 1897, p. 54.

and farther to the south. The exact boundary can be indicated only after a more detailed study of the geological structure of the area and a more thorough study of the clay shales of Tomsk Province, which occur, as can be seen, both in the Devonian and in the Carboniferous. In the future I intend to take this up. For the present, however, it may be said that our excursion collected some valuable data for forming a more correct idea of the Carboniferous in Tomsk Province, and in particular in the locality adjoining Tomsk.

The Devonian deposits have everywhere been brought out of a horizontal position.

Coal-bearing deposits.

The coal-bearing deposits have a much wider distribution in the locality through which the Tom flows. They in fact constitute the so-called Kuznetsk Basin. Without giving in detail all the points where material was collected, I shall dwell only on some of the most interesting ones. But before this it is necessary to say a few words in general about the coal-bearing series. The composition of the latter is defined as follows by the authors who have studied the Kuznetsk district. The lower division consists of dark-gray limestones with a comparatively not especially rich fauna; the upper is formed by sandstones, clay shales, and shaly clays with beds of coal, with a rich and varied flora, but a very poor fauna, consisting of small lamellibranchs (Anthracomya, Posidonomya, Carbonicola, and others).

The lower division was observed by us in various places. Above the town of Kuznetsk, Lower Carboniferous limestone could be seen opposite the mouth of the Belsa River, on the left bank of the Tom River. Here an exposure of dark-gray Carboniferous limestone extended for a rather considerable distance (about 1 verst), and a small amount of paleontological material was collected, though not in especially satisfactory preservation. This locality was described by Tolmachev¹), who cites from there a whole series of forms characteristic of the Lower Carboniferous of Siberia, such as Syringothyris Carteri Hall, Spirifer tornacensis Kon., Productus burlingtonensis Hall, and others. But our greatest attention was directed to another point: namely, to the right bank of the Tom River, a little above the village of Roika. Here, for approximately 1 verst, there extends an exposure of gently dipping limestones, which are distinguished by an extraordinary abundance of fossils. This exposure is discussed by Derzhavin²), who cites 9 forms from there, and by Polyonov³), who collected considerable material there and indicates the following determinations by Petz: Pro-

¹) Tolmachev. Proceedings of the Geological Section of the Cabinet of His Imperial Majesty, vol. II, p. 424.
²) Mining Journal, 1893, vol. III, p. 125.
³) Proceedings of the Geological Section of the Cabinet of His Imperial Majesty, 1901, vol. III, p. 179.

ductus semireticulatus, Productus punctatus, Productus longispinus, Spirifer tornacensis, Spirifer striatus, Spirifer attenuatus, Syringothyris cuspidata, Reticularia lineata, Orthotetes crenistria, Schizophoria resupinata, Derbya aff. hemisphaerica, Rhipidomella Michelini L’Ev., Hemiplet(h)orynchus fallax n. sub. n. sp., Michelinia megastoma Phill., Michelinia aff. tenuisepta Phill., Caninia Uswae Stuck., Aulopora sp., Fenestella aff. carinata M’Coy, Fenestella plebeja M’Coy, encrinites. This list also included the forms that were indicated by Derzhavin, with the exception of Productus pustulosus Phill. and Platyceras sp.

Here we made a detailed section and traced an entire series of beds. These beds dip gently downstream. According to Polynosov, the beds strike NW—290° and dip gently to the SW. They consist of argillaceous light-gray limestone, partly interbedded with grayish clays. Some beds are literally filled with fossils. Michelinia and Syringothyris cuspidata are especially abundant in certain beds. We collected here a very large amount of material, which may constitute a grateful subject for serious work. Besides many representatives of brachiopods, corals, and bryozoans, lamellibranchs, gastropods, fish teeth, a fragment of a large ichthyodorulite, and so forth were found. The fossiliferous limestones are overlain by light-gray flaggy limestones without fossils; they are of the same character as the limestones interbedded with greenish clays, marls, and sandstones on the left bank of the Tom above Roikovo. Beneath these rocks, one must suppose, lie already Devonian volcanic red tuffs, as may be judged from fragments of the latter, evidently brought from above and found along the towpath. But the direct superposition of the rocks could not be seen.

I note that the bank where the Carboniferous limestone with fossils crops out forms a series of landslides and presents a fairly well expressed karst character. There is a ledge running parallel to the bank, evidently the result of a landslide; on it there are fairly significant funnel-shaped depressions, arranged in a row along the bank. These depressions evidently arose as a result of the erosion of deeper parts of the limestone and the formation of cavities there, and then the collapse of the overlying limestone beds into these cavities. Despite the considerable thickness of the section, estimated at approximately several tens of sazhens, the fauna is rather uniform in the different beds and varies chiefly quantitatively rather than qualitatively.

Lower Carboniferous limestones with fossils were also observed by us on the left bank of the Tom near Mozzhukha, above the Verkhne-Tomsk ostrog, precisely where the Tom abuts against the left precipitous bank composed of these limestones and sharply turns away.

Here, as Venukov also indicates,^1 the limestone beds dip steeply from WSW to ONO at an angle of dip of 70°–80°; in places the beds even seem overturned. The latter is confirmed by our observations as well. Venukov cites from here a comparatively large number of Lower Carboniferous forms. We found few fossils. The section of Carboniferous deposits on the right bank of the Tom, somewhat below the Verkhne-Tomskoye ostrog, is interesting. Here, near the village of Verkhne-Tomskoye, Venukov also points to the existence of several anticlinal folds, where the cores of the folds are formed by dark-gray limestones, which are covered by alternating beds of limestones, greenish-gray sandstones, and dark clayey shales. We too observed this section, and it was possible to establish in these beds likewise a Lower Carboniferous fauna. Thus here the type of rocks of the lower division is different from what was indicated above. This section is of interest in that it sheds light on the Carboniferous clayey and sandy deposits near the town of Tomsk and upstream along the Tom. In both places not only the petrographic composition of the deposits, but also the character of the fauna, have much in common. It must be thought that here there are deposits transitional to the upper—productive—division of the Carboniferous. Venukov^2 dwells in considerable detail on the beds of sandstones and shaly clays alternating with Lower Carboniferous limestone, and from the fact of finding such beds (near the village of Verkhne-Tomskoye and the village of Balakhonka) draws the conclusion that the coal-bearing series represents a direct continuation of the Lower Carboniferous series, forming one whole with it, and supposes that for this reason the boundary between the upper and lower divisions cannot always be drawn sharply. He artificially draws it by assigning to the lower division all the interbeds of limestones with the sandstones, clays, and clayey shales interbedded with them, since these limestone interbeds have a fauna identical with that of the underlying limestones; the overlying beds of sandstones, clayey shales, and shaly clays, in his opinion, constitute the upper—coal-bearing—stage.^3

The occurrence of Lower Carboniferous fossils in the sandy-clayey series was established by us not only at the point indicated by Venukov, on the right bank of the Tom below the village of Verkhne-Tomskoye, but also at two new points: near the village of Kulakovo, on the right bank of the Tom, in gray clayey shales (see above, p. 12), and on the right bank of the Tom, 1/2 verst below the mouth of the Shumikha River, above the village of Yarskoye, where in the same clayey shales were found Syringothyris cuspi-

^1 Venukov, vol. II, issue 1, p. 50.
^2 Ibid., p. 121, and also pp. 27–31.
^3 Venukov, ibidem, p. 126.

data, Spiriferina imbricata n. sp., Spirifer tornacensis, Productus semireticulatus, and other forms, likewise indicating the Lower Carboniferous age of these rocks.

It is interesting that closer to Tomsk, in the clayey-sandy sequence, limestone interbeds apparently are no longer observed, and evidently the suite of Carboniferous sediments here is represented by a clayey-sandy facies. It is difficult at present to say whether there is exclusively a sequence here corresponding to the lower division of the Carboniferous of other parts of the Kuznetsk basin, or whether part of it also represents transitional beds to the upper division. In particular, such a question arises with regard to the clay shales near the city of Tomsk. In addition, there is also the question whether Derzhavin’s view¹ is confirmed, which saw in the clay shales a special facies of the lower division of the Carboniferous system. This question can be resolved only after a detailed study of the paleontological material from the Tomsk shales, which is precisely the subject of my work at the present time. In any case, it is beyond doubt that the composition of the lower division of the Tomsk Carboniferous is more varied than is usually thought, and that, besides limestone, it includes a considerable quantity of clay shales and sandstones—that is, it is rather a sandy-clayey-shale facies of the Lower Carboniferous. In view of the fact that the sandy-clayey-shale sequence, in petrographic character, very strongly resembles a similar Devonian sequence, they are easily confused, and it is also difficult to draw the boundary between them in the case when these sequences are in contact, as occurs between the village of Iskitim and the village of Kulakovo. It must be said, however, that in general the Devonian clay shales apparently differ in their predominantly greenish coloration, whereas the Carboniferous shales are dark gray or even black. It is probable that a more detailed study of them from the microscopic and other aspects will also reveal differences between them.

The upper division of the Carboniferous system in the Kuznetsk basin is made up of the coal-bearing sequence. It is most fully developed here. According to Polenov,² in his latest work, devoted to the description of the sheet—Kuznetsk—of the geological map of the Altai District, he finds it more appropriate to divide this sequence into two stages: a lower stage of sandstones and shaly clays with coal seams, interbeds and concretions of sphaerosiderite, and an upper stage of sandstones and conglomerates. The lower stage of greenish sandstones which he had earlier distinguished, observed in more northern districts, turned out in the southern districts not to have independent significance, and therefore—

merges with the middle stage, which under the new scheme is considered the lower stage. Venyukov¹, in the vicinity of Balakhonka, also indicates beneath the coal-bearing series a layer of sandstones, partly containing conglomerates. We observed both stages, and it could be noticed that the deposits of hard coal are confined not exclusively to the lower stage, but also occur in the upper one. Polénov dwells in detail mainly on the petrographic differences between the rocks of the one and the other stage, but this distinction cannot always be clearly traced and one or the other stage distinguished. In this respect, plant remains occurring in one or the other stage may perhaps prove useful. But this can be done only after a complete treatment of the paleontological material collected by us in considerable quantity. As regards plant remains, for the present it can only be noted that we found, in considerable quantity and almost everywhere, remains of Cordaites. These remains are represented chiefly by remains of leaves. It must be supposed that the numerous fossilized trunks, which are usually called by the general name Araucarites, also belong here. In some cases whole deposits of fossil tree trunks were found, for example, three versts below Zmeinka, where trunks up to 10 arshins long occur. The trunks have for the most part turned into flint, but there are cases of their transition into coal. In addition, Calamites and remains of ferns occur. Of the fauna, besides Najadites and small crustaceans occurring here and there, remains of insects were found at two points (three versts below Zmeinka), and at one point remains of ganoid fishes (on the right bank of the Tom below Kurganskaya).

In the coal-bearing deposits—the sandy-clayey series—cases of unequal relation to processes of weathering were observed.

The coal-bearing deposits, like the Devonian ones, have also been brought out of their horizontal position by mountain-forming processes. In many cases whole systems of folds are visible, showing that these sediments underwent complex plicative dislocation.

But alongside this there are many facts indicating that these deposits also underwent disjunctive dislocation. Veins of eruptive rocks among these deposits are the most conspicuous evidence of this.

Post-Pliocene Deposits

Above the eroded coal-bearing deposits lie sediments that are regarded as post-Pliocene. They are confined—

the Tom valley and often form broad strips on one or the other side of the channel, constituting the second terrace.

The composition of the post-Pliocene is fairly constant. To judge of this composition one may cite at least one example. Between Bedareva and Ilyinskoe, on the left bank of the Tom, there is a section of the following composition:

a) loess-like clay, thickness—9 sazhens, partly with remains of terrestrial freshwater shells.

b) Brownish laminated clay—thickness 8 sazhens.

c) Gray clay, thickness 3 sazhens.

d) Pebble bed of indeterminate thickness, overlying eroded Carboniferous deposits. As may be seen, the base of the post-Pliocene sequence is represented by a pebble bed, which lies directly upon eroded bedrock. Such a character of the post-Pliocene is observed everywhere in the Tom valley from Kuznetsk almost to Tomsk itself; nowhere above Tomsk, in the interval between the bedrock and the post-Pliocene, are deposits older than the post-Pliocene observed. Only near Tomsk is there a considerable suite of sandy-clayey beds lying at the base of the post-Pliocene; it presumably belongs to the Miocene, but a final decision on the age of these beds can be made only after the paleontological material has been identified.

In the post-Pliocene there occur, besides remains of small shells, Succinea, Pupa, and others, in large quantity the remains of large mammals. Among the latter the remains most often encountered are those of the mammoth (Elephas primigenius), then of the ox (Bison priscus), more rarely of the rhinoceros (Rhinoceras tichorhynus), and of the horse (Equus caballus). The following points may be noted where bones of these animals were found: near the village of Saltymakova, near the village of Zmeyinki—in the so-called Yellow Yar on the Bystrukha, near the village of Krapivnina, near the village of Azhendarmkaya, near the village of Bedareva, and others. (It must be said that most of the bones were acquired from various persons who had found them near their place of residence.)

Ancient and modern river deposits, making up the 1st terrace, are represented by pebble beds or sandy-clayey deposits. In places they contain peat deposits.

Igneous Rocks

The igneous rocks in the locality visited are represented by porphyries, porphyrites, diabases, and melaphyres.

A considerable area of igneous rocks is found in the so-called melaphyre horseshoe. The composition of the latter, as has already been indicated,

earlier, include the Naryk Mountains, Babii Kamen, from which eastward from the Tom begin the so-called Kailot Mountains, and the Saltymak Range. Here, everywhere, we were able to observe black melaphyre with varying structure. In this melaphyre, in many places, a beautifully expressed columnar jointing could be seen. At various points among the melaphyres, well-formed minerals were collected in amygdules, such as rock crystal, calcite, and zeolites. Especially many minerals were collected in the Saltymak Range, and then along the N. Ters. Among the zeolites in the Saltymak Range—on the right bank of the Tom—apophyllite was found; this is a new locality for this mineral, first indicated for Siberia by Privat-Docent P. P. Pilipenko¹.

Diabases were observed along the Tom above the town of Kuznetsk—at various points over the stretch between the latter and the mouth of the Bel’su River.

In one place, namely near the village of Kura on the right bank of the Tom, it was possible to see the contact of diabase with Carboniferous sandstone and to trace the contact alterations.

Diabase porphyrites were observed above the Taidon River, on the left bank of the Tom River, and also at various points along the Tom below Polomoshnaya—closer to Tomsk. These porphyrites usually form veins cutting through sandstones or clay shales of Carboniferous age.

In the present report I confine myself only to these brief remarks, leaving a detailed description until the petrographic material has been worked up. Likewise I do not touch upon the question of the age of the volcanic rocks, and limit myself to a reference to Venyukov, Polyanov, and Tolmachev, who have examined this question in sufficient detail.

Nor do I touch upon the question of tectonics, referring to the same authors.

In conclusion I shall say a few words about useful minerals. The latter are represented by extraordinary deposits of hard coal, which at present is still scarcely being worked, but which, evidently, in the future will serve as the basis of broad industrial development, when the so-called Kuznetsk coal-bearing basin attracts the attention of industrial people. I shall not cite individual outcrops of hard coal, but will point out that these outcrops are extraordinarily numerous and at the same time often very thick, while their immediate proximity to such a river as the Tom serves as a guarantee that the extraction and sale of hard coal will be carried on on a large scale. Our excursion examined the outcrops of hard coal rather—

particularly thoroughly; the conditions of its occurrence were noted, and numerous samples of coal and of the rocks accompanying it were collected. Alongside the coal it is necessary to point out deposits of spherosiderite, which is confined to the same coal-bearing strata as the coal. One must suppose that it too will play a not insignificant role in the development of industry in the Kuznetsk Basin.

Finally, one may point to the presence of galena in the volcanic breccia on the left bank of the Tom, somewhat above the mouth of the Taidon River, near the outcrop of Upper Devonian rocks mentioned earlier—point No. 76 of our diary (see p. 9). But it should be noted that the galena was found in such negligible quantities that there is no reason to speak of its significance as a material for extraction.

Tomsk. 1910.

Prof. M. Yanishevsky.

1. See Yearbook of Geology and Mineralogy of Russia, vol. X, issues 7–8, p. 189. ↩↩↩↩↩↩↩↩↩↩↩↩

2. Polenov, vol. VI, issue 1, pp. 457–459. ↩↩↩↩↩↩↩

3. See Polunov, ibidem, p. 294. ↩↩

4. See ibidem, p. 10. ↩↩

5. Venukov, p. 9. ↩↩

6. Polunov, vol. VI, pp. 294–295. ↩