Clay Mineral Assemblages in the Cretaceous Volcanogenic–Sedimentary Rocks of the North-Western Part of the Transition Zone from the Asian Continent to the Pacific Ocean

: In this study, clay and non-clay minerals in the cement of Cretaceous volcanogenic– sedimentary rocks from the bottom of the marginal seas of the north-western Paciﬁc Ocean and adjacent areas were studied. Corrensite and mixed-layer chlorite–smectite, rectorite and mixed-layer illite–smectite, chlorite, swelling chlorite (?), illite, kaolinite, smectite (?), calcite, ankerite, barite, gypsum, epsomite, zeolites (laumontite, analcime, and stilbite), cristobalite, and quartz were determined. The following are the indicative properties: (a) minerals: corrensite and rectorite; (b) associations: corrensite–chlorite, corrensite–chlorite–laumontite, corrensite–epsomite–authigenic calcite, and quartz–illite. Such minerals indicate that the thickness of the accumulated sediments in the studied basins could reach three to ﬁve kilometers and that the temperature of their formation could be higher than 150 ◦ C. Transformations in the process of diagenesis and epigenesis occur in two di-rections: smectite–rectorite–mica, with an excess of potassium, and smectite–corrensite–chlorite, with an excess of magnesium. The chlorite–corrensite association may indicate conditions favorable for seawater evaporation, and the presence of laumontite in the corrensite–chlorite association suggests a periodic supply of calcium to the sedimentation basin. The illite–kaolinite association is probably associated with coal accumulation in epicontinental conditions and a warm humid climate in nearby areas. Periods of sedimentation, possibly associated with global climate events, were identified: 113–120, 110–113, 105–110, 93–95, 72–83 and 61–72 Ma. The established time intervals and mineral associations can serve as benchmarks for stratigraphic constructions in reconstructing the physicochemical, climatic parameters, and conditions of Cretaceous volcanogenic–sedimentary strata accumulation.


Introduction
Clay minerals are sensitive indicators of sedimentation conditions, indicating changes in the paleogeographic setting and the nature of the dia-and epi-genetic transformations of sedimentary material. Layered silicates (smectite, corrensite, and rectorite) in association with other minerals have the greatest indicative features. They can be useful in determining the climatic, physical, and chemical conditions of sedimentation and stratigraphic constructions, and in clarifying the geological development history of the studied region.
The Cretaceous period in the history of the Earth is interesting not only from the point of view of global events occurring during this time but also in terms of the huge mineral reserves concentrated in the deposits synchronous with it. In the Far East Region, Cretaceous rocks occupy a significant part of the territory. Hundreds of papers have been written on the geology, stratigraphy, and mineral resources of this area. However, mineralogically, the rocks of this period are less characterized, especially from an authigenesis point of view. There are only separate works [1][2][3] on some regions of the Russian Far East. The purpose of this work is to summarize the mineralogical studies carried out by the author on the Cretaceous rocks of this area.

Methods
Rock samples collected from the abovementioned area were mainly studied using X-ray diffraction, as well as electron and optical microscopy, thermography, and chemical analyses as additional tests. The phase structures of the clay and non-clay minerals were determined from bulk rock cement. The samples were crushed in an agate mortar and sieved to a size less than 0.06 mm. The resulting fractions were prepared in an aqueous suspension and applied to a glass slide for orientation. They were analyzed under different conditions [4,5]: air drying, glycol saturation, and heating for three hours at 550 • C. Some minerals selected under a binocular microscope were prepared with alcohol and analyzed in powder. On a fraction smaller than 1 µm, which was obtained from some samples by gravity sedimentation [4], a silicate wet chemistry analysis with atomic absorption ending on AA-6800 (Shimadzu, Japan) was carried out. The following tools were used: a "Dron-2.0" diffractometer (NPO "Burevestnik", Russia) with Cu Kα radiation (flat graphite monochromator), an anode voltage of 40 kV, and a current of 30 mA; an optical polarizing microscope, "Amplival" (Carl Zeiss Jena); and a derivatograph, "Q-1000" (Paulik, MOM, Budapest, Hungary). Electron microscopy and optical microscopy were applied for layered silicate morphology, microstructure determination, preliminary descriptions, and mineral formation staging. The determination of mixed-layer formations was carried out according to [4][5][6][7].

Material
The material for this study was sampled from Cretaceous volcanogenic-sedimentary rocks (Figures 1-6, Figure S1 [8], Table S1), obtained by the author on field trips to the Primorye Region during coastal expeditions to the Sakhalin (the Terpeniya Peninsula) and Shikotan islands in 2000-2009. It was obtained via dredging in the Sea of Japan (the Yamato Upland) and the Kuril Island Arc (the Underwater Vityaz Ridge), and data on the Kamchatka Peninsula (western part, the Palana Section) were obtained. During the coastal trips, mainly coarse-grained rocks (sandstones, tuff sandstones, and the cement of gravelites and conglomerates) were selected with a sampling frequency of 10-50 m in normal layering and without visible traces of alterations. Sometimes, fine-grained rocks were studied. Each sample dredged from underwater uplands was also analyzed. Using an X-ray analysis, the author personally analyzed over 1200 samples of Cretaceous rocks from the Primorye Region (≈900), the Yamato Upland (Sea of Japan, ≈50), the Terpeniya Peninsula (Sakhalin Island, ≈20), Shikotan Islands (Lesser Kuril Arc, ≈200), the Underwater Vityaz Ridge (≈50), and the Palana Section (Western Kamchatka, 10).
Clay minerals developed in the Cretaceous volcanogenic-sedimentary rock cement of the northeastern part of the transition zone from the Asian continent to the Pacific Ocean are represented by chlorite, illite, swelling chlorite, vermiculite (?), kaolinite, smectite (?), corrensite, mixed-layer chlorite-smectite, rectorite, and mixed-layer illite-smectite varieties. Non-clay minerals are calcite, ankerite, epsomite, tschermigite, gypsum [27], barite [28], zeolites (laumontite, analcime, and stilbite), cristobalite, goethite, quartz, and plagioclase (Figures S2-S8 [25,26,29]). Smectite and mixed-layer formations of the smectite-illite type (low-ordered, R0) are very rare in Cretaceous rocks. Mixed-layer illite-smectite (highly ordered structures, R1) appears at the turn of the Paleogene and Cretaceous, as well as regular mixed-layer chlorite-smectite (corrensite) ones. Cristobalite is occasionally found in the rocks of the Maastrichtian-Danian (Uchirskaya Suite, the Terpeniya Peninsula) and earlier periods. Kaolinite is only found in the Triassic and Lower and Upper Cretaceous rocks of Primorye, and on the Yamato Upland (Sea of Japan). The sulfate group of minerals (epsomite, gypsum, barite, tschermigite, and ankerite) is only present in the Lower Cretaceous rocks of the Yamato Upland (Sea of Japan). Zeolites: laumontite is found in the Cretaceous and Paleogene rocks of Primorye and the Lower Cretaceous rocks of the Yamato Upland; analcime and stilbite predominantly developed in both sedimentary and volcanogenic-sedimentary rocks of the Lower and Upper Cretaceous. Carbonates: calcite is very common in Cretaceous rocks in the forms of veins and veinlets, and ankerite (possibly redeposited, slightly rounded) is only found on the Yamato Upland (Sea of Japan).
The mineral associations found in the Cretaceous rock cement of Southern Primorye are chlorite-illite (illite-chlorite), corrensite-chlorite, chlorite-corrensite-mixed-layer chloritesmectite-laumontite, illite-rectorite-mixed-layer illite-smectite, and illite-kaolinite-quartz. The Yamato Upland (Sea of Japan) is characterized by the above associations, but the mineral composition is much richer. The composition of the mineral associations in other studied areas is somewhat poorer. No illite-kaolinite-quartz (no kaolinite) association is found. A chlorite-corrensite-mixed-layer chlorite-smectite association is rare, and laumontite is absent (not determined?), but other zeolites are present.

Discussion
Before beginning, it is necessary to agree on the terminology and nature of the minerals found in the cement of the studied rocks.
As for the nature (authigenic or detrital) of clay minerals, the author accepts the statement that most of the rock cement is authigenic, as it is believed that a fraction of less than 0.06 mm is represented mainly by this and only an insignificant part of it can be involved in the grinding from clasts [4,[34][35][36]. As a rule, these are quartz and plagioclase.
This statement is partially confirmed by viewing thin sections, where it can clearly be seen that corrensite, kaolinite, illite, and quartz are authigenic ( Figure S8a-c). In the case of mica (illite), this is also confirmed by electron microscopic studies ( Figure S8d), as well as the diffraction patterns of samples of various ages. In modern sediments, we observe sharp, high, symmetrical peaks of detrital mica and chlorite. With the aging of sedimentary rocks, the peak belonging to smectite (001) begins to increase in intensity and narrows. The peaks of terrigenous mica and chlorite decrease significantly. Highly ordered mixed-layer illite-smectite and chlorite-smectite formation types begin to appear in the cement of Oligocene rocks. Corrensite and rectorite are maximally developed in Paleogene and Upper Cretaceous rocks. In the Lower Cretaceous rocks, we observe the presence of chlorite in association with corrensite and laumontite, and illite. In the rocks of the Jurassic and older, we still mainly find the illite-chlorite association.
Some non-clay minerals are also authigenic. These are laumontite (Figures S7 and S8b), sometimes quartz ( Figure S8c), epsomite, tschermigite, barite ( Figure S7), cristobalite, and calcite. Ankerite may be terrigenous. In thin sections, it looks slightly rounded. This is also the case for analcime in the Lower Cretaceous rocks of the Yamato Upland, which is represented by formations that look similar to ooids or peas, as if impregnated in the rock. In other areas, analcime can develop over pyroclastic fragments. This is also the case for other zeolites, which are widely represented in Upper Cretaceous rocks.
Therefore, we can confidently consider corrensite, rectorite, laumontite, illite, epsomite (interlayer in siltstone), tschermigite, barite (crusts on slip mirrors), sometimes quartz ( Figure S8c), and cristobalite (interlayer in radiolarite) as authigenic. As conditionally authigenic, we can take chlorite, calcite, sometimes ankerite, and analcime. The remaining minerals can be considered detrital. Therefore, the main emphasis in our discussion focuses on the confidently authigenic minerals. However, nature (origin) is not so important from the author's point of view. The appearance of minerals in rocks of the same age from different regions is much more important.
The most representative results of the mineralogical analysis were obtained for the Lower Cretaceous rocks of South Primorye [9,10]. The samples from the Upper Cretaceous rocks of Primorye (Primorskaya Series) are much less characterized. The new data (Table S1) did not change the previously obtained conclusions. In the Upper Cretaceous rocks, there is a tendency for the predominance of the illite-chlorite association, the greater presence of mixed-layer chlorite-smectite and mixed-layer illite-smectite, illite, swelling chlorite (?), and stilbite. There is a decrease in the content of corrensite and rectorite. Kaolinite is absent.
In the distribution of minerals and mineral associations in the cement of the studied Cretaceous rocks, latitudinal, age, and chemical zonation are observed. The southern (a) and northern (b) zones can be distinguished as follows: (a) characterized by the presence of kaolinite and minerals of the sulfate group in the Lower Cretaceous rocks of the Yamato Upland (Sea of Japan), possibly the Primorye Region, and a weak magnesian content of mixed-layer chlorite-smectite formations (Tables 1 and 2) [1,2,25,26,37], and (b) distinguished by the absence of minerals of the sulfate group and kaolinite, and a slightly increased magnesian content of mixed-layer chlorite-smectite varieties. Age zoning is expressed as follows: in the Lower Cretaceous rocks, chlorite-corrensite and chlorite-corrensite-laumontite associations dominate; in the Upper Cretaceous rocks, the role of the mixed-layer chlorite-smectite and mixed-layer illite-smectite formations with the appearance of analcime and stilbite is increased. (n = 4) (n = 4) (n = 2) (n = 2) (n = 6) (n = 2) (n = 3) (n = 3) (n = 1) (n = 3) (n = 3) (n = 6) (n = 7) (n = 10) (n = 3) (n = 3) (n = 6) (n = 6) (n = 6)  The main conclusions made earlier [9] are that the chlorite-illite (illite-chlorite) association is found in all formations and that it cannot be determinative by itself. For the kaolinite-illite association, the time of formation can be established as Aptian-the beginning of the Early Albian-113-120 Ma (coal accumulation, the "Lipovetskoe" period, is noted in the Lipovetskaya Suite, Suchanskaya Series, and North Yamato Ridge). For the corrensite-chlorite association, it is the beginning of the Early Albian-110-113 Ma (noted in the Lipovetskaya and Galenkovskaya Suites, and Suchanskaya and Korkinskaya series); for the corrensite-chlorite-laumontite association, it is the second half of the Albian-105-110 Ma (the "Galenkovskoe" period, which is recorded in the Galenkovskaya Suite, Suchanskaya and Korkinskaya series, and South Yamato Ridge); and for rectorite, it is the Late Cenomanian-93-95 Ma (the "Korkinskoe" period, reddish color sediments of the Korkinskaya Series (Romanovskaya Suite)).
Therefore, within the "Lipovetskoe" period, we have two events: one for the kaoliniteillite association, 113-120 Ma (coal accumulation epoch), and one for the corrensite-chlorite association, 110-113 Ma; this period is comparable to the Early Albian event (Paquier event, OAE 1b, 111 Ma). For the "Galenkovskoe" period (the presence of laumontite), the interval can be defined as 105-110 Ma. The nearest global events with a marked supply of calcium in sedimentary deposits are recorded at the boundaries of 103, 105, and 107.5 Ma, corresponding to Urbino, OAE1c, and OAE1d, respectively. Such a multiplicity can be explained by the repetition of events increasing calcium supply to the sea basin, i.e., there may be several supply periods, and they may not yet have been sufficiently studied in these deposits.
The formation interval of the reddish colored sediments of the Korkinskaya Series (upper part of the Romanovskaya Suite) is 93-95 Ma (the epoch of lateritic weathering), which coincides in time with the Cenomanian-Turonian events (OAEs-Bonarelli event, C/T OAE, OAE2,~93 Ma).
In general, the proposed scheme of mineral formation for the Cretaceous rocks of Southern Primorye [9] does not undergo any special changes. Therefore, it becomes possible to extend the information obtained to areas with a lesser degree of knowledge.
The new data obtained make it possible to identify at least two more periods in the Upper Cretaceous stage of sedimentation, probably associated with the existence of conditions favorable for the evaporation of seawater (corrensite association). In the Primorskaya (mainly volcanic) Series, corrensite is found in sandstones in the areas of Zalesye Village [9] and Dal'negorsk area (Table S1). The problem of sandstones in that strata is debatable. Both olistostromal and normally sedimentary origins are possible. Consequently, the deposits of this period (Santonian-Campanian, 72-83 Ma) require more detailed studies.
In the rocks of the Maastrichtian-Danian period, another event appears, which is recorded in almost all Upper Cretaceous rocks (Table S1). Corrensite, mixed-layer chloritesmectite and rectorite, and mixed-layer illite-smectite encountered the most likely fall on the sediments bordering on the Upper Cretaceous deposits. These are the Uchirskaya (Terpeniya Peninsula and Sakhalin Island) and Malokuril'skaya (Shikotan Island) Suites, and basement rocks on the Vityaz Ridge (Maastrichtian-Danian, 61-72 Ma). It is possible that the pyrite of the black shales found on Shikotan Island reflect an OAE1d event (Campanian-Maastrichtian).
These include coastal marine conditions, some with the possible evaporation of sea water, and others under conditions of adjacent chemical weathering. Detailed locations and descriptions of these deposits are given in [9] ( Figure S2).
The latest data [38] for the south of Primorye Region give two absolute ages for the Early Cretaceous period of coal accumulation-118 ± 1.4 and 109 ± 1 Ma for the Lipovetskaya (Nikanskaya Series) and Frentsevskaya (Suchanskaya Series) Suites, respectively. Now, it is possible to specify the time of existence of the kaolinite-illite association (the period of coal accumulation or the first "Lipovetskoe" event); the time is older than 118 ± 1.4 million years and in the region of 109 million years. P.V. Markevich [3] notes the appearance of kaolinite in the section of the Cretaceous rocks of Primorye in three periods-Barremian-Aptian, Aptian-Albian, and the end of the Albian (129-125, 125-113, and 100 Ma, respectively). Chlorite prevails in the interval of 113-100 Ma, which coincides with the periods and conditions of sedimentation identified by the author [9]. The chloritecorrensite suites in this study are confined to Cretaceous sedimentation periods between 119 and 109 Ma, whereas the other identified mineral suites range in age between 129 and 100 Ma.
A special role should be assigned to the corrensite-laumontite association. The corrensites found in the Cretaceous rocks of the studied region ( Table 2) are similar in chemical composition to the Fe-Mg-corrensite minerals of the Cretaceous coal-bearing formation of Western Verkhoyansk [33]. Such an association of corrensite-laumontite is fairly well characterized in [39][40][41]. It is widely believed that laumontite is a function of depth and temperature, while corrensite is formed due to the femic components of volcanic-sedimentary material with intermediate and basic compositions. The author suggests a different nature of this association in which smectite (sepiolite and palygorskite?) is formed under conditions close to evaporitic conditions (seawater evaporation), and laumontite (or some other zeolite) with an increased content of calcium in sandy sediments is formed after smectite (fills the pores later), with both of them, smectite and zeolite, being transformed during epigenesis into corrensite and laumontite. Calcium carbonate can form concretions (boudins) and secondary fissured veinlets common in Cretaceous rocks. In these cases, the relevance of finding calcite together with laumontite and corrensite should be studied more carefully. In the Primorye Region, corrensite in association with laumontite is found at least in the Lower Cretaceous and Paleogene-Neogene rocks. In the Upper Cretaceous rocks, the zeolites of stilbite and heulandite types predominantly develop, which is also noted in [33] for the coal-bearing formation of the Western Verkhoyansk Region. Therefore, a similar regularity can be found in other sedimentary coal-bearing basins of the Far East.
It should be assumed that some of the Lower Cretaceous rocks of the Yamato Upland (Sea of Japan) may also have similar stages in sedimentation since similar mineral associations have been identified there (Table S1).
Some rock samples of the North Yamato Ridge are probably from approximately 118 ± 1.4 Ma (kaolinite-illite association) and possibly a little younger (113-115 Ma, due to the presence of corrensite and mixed-layer chlorite-smectite varieties). The age of some samples of the Southern Yamato Ridge can vary from 118 ± 1.4 to 109 ± 1 Ma (due to the presence of kaolinite and corrensite with laumontite, respectively). The presence of epsomite, barite, ankerite, and analcime, and the signs of brine evolution in silty mudstones [22] indicate that the conditions for the evaporation of seawater in the Early Cretaceous in the area of the Yamato Upland were more pronounced than in Primorsky sedimentary basins. It is possible that, in the Late Cretaceous, the area of the Yamato Upland could serve as a zone for the supply of sedimentary material to the regions of Southern Primorye for deposits similar to the upper parts of the Korkinskaya Series (Cenomanian?). Some samples of stations 1410b and 1411 (Table S1) are massive goethite, which could be formed during lateritic weathering or under an oxygen-rich environment [42]. It is true that no similar specimens have been found in the Southern Primorye to date.

Conclusions
When analyzing the clay mineral assemblages of Cretaceous rock cement in the transition zone from the Asian continent to the Pacific Ocean, the following six periods in sedimentation are distinguished, possibly associated with world global climatic events: 113-120, 110-113, 105-110, 93-95, 72-83, and 61-72 Ma. The first three periods are confirmed by absolute data [38], but the others require clarification.
According to M.A. Levitan et al. [43], during the Cretaceous, up to six or more temperature maxima could be observed, during which salt-bearing deposits could form under the conditions of seawater evaporation.
The conclusion is confirmed that, for the Lower and Upper Cretaceous rocks of this region, analcime or laumontite facies of epigenesis are possible [44]. During epigenesis, two parallel processes are observed: (1) the progressive transformation of smectite into mica under "oxidizing" (environment saturated with oxygen) [45] conditions in the presence of potassium and (2) chloritization under the condition of an excess of calcium and magnesium under "reducing" (oxygen deficiency) conditions, i.e., the transformation of smectite into mica reflects the course of epigenetic processes, while the transformation into corrensite reflects the specific conditions of sedimentation for a given region [33,46,47]. It should be noted that, in the direction from south to north, the magnesian content of corrensite increases (Table 1), which may indicate a meridional orientation of the salinization process.
Supplementary Materials: The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/min12070909/s1, Table S1: Clay and non-clay minerals in Cretaceous rocks cement of the studied area; Figure S1: Geological map of the central part of Primorye Region; Figure S2: Oriented X-ray diffraction patterns of the main associations of clay and non-clay minerals in the Lower Cretaceous sedimentary rocks cement; Figure S3: Oriented X-ray diffraction patterns of clay and non-clay minerals in the Lower Cretaceous sedimentary rocks cement of the Northern Yamato Ridge; Figure S4: Oriented X-ray diffraction patterns of clay and non-clay minerals in the Lower Cretaceous sedimentary rocks cement of the Northern Yamato Ridge; Figure S5: Oriented X-ray diffraction patterns and thermograms of mixed-layer chlorite-smectite minerals in the Lower Cretaceous sedimentary rocks of the Southern Yamato Ridge; Figure S6: Oriented X-ray diffraction pattern of the Upper Cretaceous sedimentary rocks cement of Palana Section (Western Kamchatka, sample 87d); Figure S7: Powder X-ray diffraction patterns of minerals in the Lower Cretaceous sedimentary rocks of the Southern Yamato Ridge; Figure S8: Images from polarizing optical and electron-microscope of the well-sorted Lower Cretaceous sandstones of the Yamato Upland.
Funding: This work was supported by the Ministry of Science and Education of Russia (project 121021700342-9).

Data Availability Statement:
The data presented in this study are available on request from the author.