Tertiary Formation Research Articles

山口県西部地方のウラン鉱床

A weak radioactive anomaly (0.080mR/hr) was detected at Yuya in 1959, but since then no furthur efforts in prospection have been undertaken in the area, since at that time it was not customary to attach much value to such occurrences. In November, 1966, significant radioactivity (1.7mR/hr, 0.6% U3O8) was detected 35m south of the previous location, in the course of a systemafic car-borne radiometric survey undertaken by the Atomic Fuel Corporation of Japan. To date, several uranium occurrences have been discovered in formations belonging to the Cretaceous Period. This is the first instance of such occurrence in Cretaceous formation discovered in Japan.The Yuya uranium deposits occur mainly in dark gray to brown, hard compact sandstone and/or sandy shale. The deposits appear related to rhyolitic rock intrusions. A secondary uranium mineral, believed to be autunite, is sporadically found in the black silicified sandstone closely associated with pyrite and chlorite. Little uranium would appear to be contained in such clay minerals as chlorite according to radioluxograph and X-ray fluorescent examination, since primary uranium minerals have not yet identified.So far prospection for uranium deposits in Japan have been directed mostly to the Neogene Tertiary just above the granitic host rocks. The discovery of the Yuya deposits in Cretaceous formation is highly significant in that it has opened up a vast new area to prospection in strata other than Tertiary formation, and this urges us to continue our efforts in gathering further information that should contribute to a better assessment of the domestic uranium potentiality.

Cenozoic oolitic iron ore, Paz de Rio, Boyaca, Colombia

The oolitic iron ore in the lower Tertiary Concentracion formation 'records a unique episode of chemical sedimentation' that seems anomalous in this succession of essentially nonmarine detrital sediments. The bed of ore, with its basal sandstone, is 2 to 20 m thick and has been traced for 20 km. Red goethitic ore contains 45 percent Fe, green siderite-chamosite ore 35 to 40 percent Fe.

Methods concerning the Subsurface Study of a Littoroal Lowland viewed from an Applied Geologic Stand Point

It is difficult for an engineering geologist who participates in exploitation on a large scale to learn an underground condition of alluvial plains, without plenty knowledge of soil mechanics, hydrodynamics, geophysical prospecting, boring techniques and so on. Practical utility is the most significant essence for the establishment of engineering geology. The writer intends to approach to the aim at this stage, having a perfect command of geology, together with fundamental knowledge of geophysics, geochemistry and civil engineering.The writer has investigated the 25 areas among the extensive littoral lowland in Japan by way of boring method during these seven years, in order to learn the underground condition. He has known the fact that the bore hole attains to the Tertiary formation within the average depth of 150 200 meters even in the deepest case ; that is an unconsolidated deposit has accumulated from the earth surface down to the depth, underneath which a harder formation has been found. These researches have utilized the newer method of prospecting, such as electric prospecting, lifting-up subterranean water, soil mechanic test and chemical analysis of pore water of boring cores etc. He describes the nature of the underground structure of the districts surveyed, illustrating a few examples.Then the writer explains means for study necessary for the localization of industry upon a littoral lowland. It is a important problem whether the ground of sites can be borne against the weight of the building of factories or not. There are soft grounds, the bearing-power of which are less than 10t per m2, everywhere in a littoral plain. An engineering geologist has tried to search for various kinds of prospecting methods, which occupy an indispensable part. The writer explains a few techniques for prospecting bearing-power of grounds, viz, standard penetration test (N-value method) and sounding method of Sweedish mode etc.Measurement of void water-pressure in a stratum can determine stability of grounds or solve land subsidence. The writer recommends and explains an instrument named Sakata P. P. R. void pressure meter fitting for in situ test, introducing a few instances of success.Engineering geologist must make efforts for counter-measures in the prevention of disasters in a littoral lowland, such as land subsidence in the main industrial regions and quick sand phenomenon after a severe earthquake. Since the writer has touched on the character and origin of the two phenomena previously, he has been able to account for a detail status quo of the studies in Japan.

On Oil Indications met with in Tenkari Coal-field, Horokanai, Hokkaido, with Refference to their Source Formations

Tenkari coal-field coveres the junctional area of three counties, Uryu, Tomamae and Embetsu, and consists of the Neogene Tertiary coal-or lignite-bearing formations overlying the Cretaceous basement. Several oil indicating localities have hitherto been reported from the coal-field by several geologists. The writers newly added several localities and from which obtained oil samples for study. As has been carried on the chemical analysis of those samples, the following facts were recognized.(1) The oil-sand from the Cretaceous containes too small quantity of crude oil for quantitative analysis.(2) The crude nature of the sample obtained from the seepage in the Quaternary of the Kamisekiyuzawa area [Loc. No. 1 in fig. 1] is quite different from that of one from the Tertiary formation of the Sanjussenzawa area [Loc. No. 6 in fig. 1]. As comparing with data of the nature of Japanese crude oil already known, the former belongs to the older type or the Cretaceous-Palaeogene oil type and the latter to the younger or the Neogene oil type [figs. 2-5].Judging from the subserface geological data to the former seepage, it seems to the writers to be possible that this seepage is fed with crude oil generated in the underneath Cretaceous deposits through the conceald fault.

Changes in Polybutadiene Rubber under Various Conditions of Aging

Abstract 1. The systematic relations of the oxidation of SKB under the action of heat, light, and ionizing radiation are considered and it is shown that the formation of a series of oxygen-containing products takes place (hydroperoxides, alcohols, aldehydes, ketones, acids, ethers, and esters). The general tendency for formation of these compounds was clarified for each separate case. 2. The behavior of double bonds of various configurations (1,2 and cis and trans 1,4) reveals differences in reactivity, namely: in the thermal, light, and radiation reactions, a decrease of the number of double bonds in the 1,2 position takes place, in general this is due to crosslinking and formation of volatile acids, but in the radiation reaction it is also due to hydrogenation. The increased rate of the decrease of the number of cis 1,4-bonds is in all cases interpreted as evidence of isomerization to the trans-configuration. It was shown that migration of 1,4 double bonds along the chain towards the tertiary carbon atoms and formation of conjugated double bonds (band at 1595 cm−1) takes place. 3. A decrease of the number of double bonds in the backbone (cis and trans 1,4) takes place that is mainly due to the formation of oxygen-containing compounds. Therefore, the quantitative investigation of this process can give an idea of the level of oxidative degradation. 4. The increase of the total absorption in the region 1400 to 750 cm−1 is connected with crosslinking. This, together with other existing methods (investigation of equilibrium swelling and stress relaxation) can be used for the estimation of the degree of crosslinking.

On the Occurrence of Geothermal Products in Japan

Geothermal areas in Japan are distributed along Quaternary volcanic zones. Fumaroles and hotsprings in these areas issue from younger volcanic rocks and origin of them seems to be related to Quaternary volcanic activities, though a few jet from Tertiary granitic rocksThermal activities in these areas are divided into two types : One is caused by emanation of shallow magmas of active volcanoes like as Atosanupuri and Showa-shinzan in Hokkaido and Iwojima in Kyushu which are characterized by high temperature and strongly acidic gases, the other is originated by consolidation of deeper magmas.One of characteristic appearances of geothermal areas in Japan is that surface thermal indications are poor. But, according to investigations made in some areas, it has become clear that geothermal products are reserved in porous beds and permeable hard rocks of younger volcanics and their basements. For example, hot water occurs from Tertiary formation covered by younger andesite lava flow in spite of lacking remarkable surface indications, in Matsukawa area, Iwate Prefecture. Occurrences in other areas may be analogous to that of Matsukawa.To know more clearly subsurface structures in geothermal areas, investigations by drilling are necessary.

Upper Cretaceous and Tertiary Stratigraphy of Guatemala

Upper Cretaceous and Tertiary sediments cover more than half of Guatemala and were deposited in the Chapayal basin, an extension of the Gulf Coast embayment. The basin's foredeep lies between a southern borderland and the Yucatan foreland. Deposition in the Caribbean was connected during late Mesozoic and early Cenozoic time with the deposition in the Chapayal basin by the Sarstun portal. The first age-identifiable sediments are the Carboniferous and Permian. The earliest Gulf Coast embayment deposition in the Chapayal basin was probably that of the late Jurassic Todos Santos Formation, followed by the thick Lower Cretaceous carbonates and evaporites of the Coban Formation. Overlying the Coban, the Upper Cretaceous units--which have an aggregate thickness of approximately 1,750 meters--include Senonian limestones of the Campur Formation and younger clastics of the Verapaz group. The latter consists of the Chemal, Sepur, and Lacandon Formations deposited in early episodic Laramide stages, with the Chemal and Sepur in the foredeep region and the Lacandon on the foreland. The Chemal and Sepur are an argillaceous facies, but the Chemal was deposited only in the region of the present-day Cuchumatanes Mountains and is preserved under distinct environmental conditions in synclinal and downfaulted valleys at elevations exceeding 10,000 feet. The shelfal Lacandon Formation is detrital limestone. Five early Tertiary and six late Tertiary formations occur in the Chapayal basin and Amatique embayment, and cover more than one-third of Guatemala. Previously, only the Rio Dulce and Toledo have been mentioned formally in the literature. The Sepur, thought by Sapper (1937) to be Eocene, is now known to be Cretaceous at the type locality and in other areas. The early Tertiary formations are assigned to the lower Eocene Peten Group. They were deposited contemporaneously and are differentiated on lithology and basin position. The Reforma, Cambio, and Toledo are the shaly formations in the foredeep region. The Toledo occurs only in the Amatique embayment. Shales with conglomeratic lenses characterize the Cambio, and softer clay shales identify the Reforma. The shelfal formations are the anta Amelia and Buena Vista, defined separately by an extensive basal gypsum bed in the overlying Buena Vista. Carbonates and evaporites occur in both formations, but evaporites predominate in the Buena End_Page 425------------------------------ Vista. The thickness of the Peten Group is 1,500 meters. Mid-Tertiary non-deposition divided Tertiary sedimentation into early and late periods. Late Tertiary sedimentation is represented by Oligocene to Pliocene deposits in the Chapayal basin and by Miocene to Pliocene(?) deposits in the Amatique embayment. The Chapayal basin formations are the Desempeno conglomerate, the Lacantun, and the Caribe which have an aggregate thickness of 1,500 meters of terrestrial and deltaic claystones, sandstones, and conglomerates. The Amatique embayment is a graben continuation of the Bartlett trough. The Miocene Rio Dulce Limestone is its oldest late Tertiary formation. Following late Miocene uplift, clastics of the Pliocene(?) Herreria and Armas Formations were laid down. The Rio Dulce has a thickness in excess of 1,000 meters, the Herreria 240 meters, and the Armas 2,500 meters. The seas withdrew at the end of the Pliocene. Quaternary depo its mask older rocks in some areas.

Geology and Hydrocarbon Deposits of the Shonai Basin in Yamagata Prefecture, Japan

Recent deep drilling by Teikoku Oil Co. is adding much new subsurface geologic information, making possible an interpretation of the central portion of Shonai Plain. The present study is a report on the subsurface stratigraphy and the structure of that region, related to hydrocarbon deposit. Three matters in particular are reported. 1) There is a newly discovered Jurizuka Uplift which is gently descending to Sakata city and increasing the thickness of the tertiary formation to the north. 2) The gentle anticlinal structure is disclosed near Sagoshi and its core is composed of the pyroclastic sediment of green tuff formation. On the crestal part of this anticrine, a small amount of hydrocarbon is found, but not so productive as the lacking of the potential reservoir. 3) The writer discusses the petroleum accumulation in Narahashi-Ishinazaka oil field, related to the sedimentation and the growth history of each anticline in Shonai Basin.

Prtroleum Geological Study on Tenpoku District in Hokkaido, Japan

In Tenpoku district, petroleum exploration has been continued from 1914, but only 6 oil and 1 gas pools have been discovered, and their main producing horizon is neogene Mapsuporo formation. Considering the variation of lithofacies and thickness of neogene tertiary formation of this district, it can be distinguished that the geological condition during the deposition of these formations undergo considerble transformation and fluctuation. The writer can explain these phenomena more clearly for Masuporo and Wakkanai formations, because at those stages more geological data are available. At Masuporo stage, it is recognized that there were several uplift parts such as Masuporo, Matsuozawa, Kiyokawa and Chikubetsu, and depression areas such as Magaribuchi, Utakoshibetsu and Sarakitomanai.The nature of these uplift and depression areas are different in their genesis and development. From the earlier stage of Magaribuchi, Soya, and Onishibetsu, some parts of these differences had been succeeded.But later Wakkanai stage, the configuration of the sedimentary basin is widely changed and simplified. The center of sinking is clearly distinguished along Wakkanai-Sarakitomanai trend, and the west and east margins of the basin are graduary made clear of their presence. The writer presents a hyposesis to explain the mode of occurence of petroleum in Tenpoku district.

Tertiary Formation Along the Northern Part of the Itoigawa-Shizuoka Tectonic Line

Tertiary Formation Along the Northern Part of the Itoigawa-Shizuoka Tectonic Line

Newly Discovered Tertiary Formation Exposed at Tabayama in Yamanashi Prefecture

Newly Discovered Tertiary Formation Exposed at Tabayama in Yamanashi Prefecture

Geomorphological Study in Kawasaki Basin, MiYagi Prefecture

The writer studied three basins which belong to the catchment area of the Natori River. The surroun-ding area are the table lands of tertiary formation composed of the Takadate andesite, liparite and the marine and Paleo-lake deposits. The Kawasaki Basin of rectangular form lies between the Takadate and the Akyu table lands, and the slender Hasekura basin and the complicated Tsubonuma-Sugo basin in the latter. Near them the two tectonic lines, named Nagamachi-Rifu and Hisanohama and Iwanuma, run or the east bounding the table lands form the Sendai coastal plain, and another one of importance meaning is the Murata thrust fault in the southwestern part of the Takadate table land. After surveys in the field, the writer concluded as follows. 1) All the three basins are the tilt block basin by Jhonson (or the fault angle depression by Cotton). No fault lines have been informed by geolagist, but the topographical features prove the dislocation. The evidences in the Kawasaki basin are the presence of the terminal facets and the fans and the narrow disturbed zone of the formation along the linear margins of the basin (the two sides of it having the different formation). In the Hasekura basin, the steep and linear northwestern slope is contrary to the gentle and comlicatec southeastern slopes with the terminal facets and the geology and the surface geology differ between then (the gravel bed in the case of the former and the loam in the latter). In the Tsubonuma-Sugo basin, the dislocation is supposed form the displacement of the plane of the surrounding table lands and the steel diffs of the western margin which prolongs to the Murata Fault. 2) The Kawasaki basin and the Tsubonuma-Sugo basin are the lake basin. In the former, two group of the horizontal patches (180m and 220m above sea-level) are dominantly adhered to the hill in the basil and further its corresponding delta sediments and deposits are observed in the western part. In the latter, the thick clay deposit and peat show the fact of the lake at the cottom.

Tertiary granites in the northeastern Japan I

Many granitic rocks occur in the Green tuff region of the northeastern Japan. Many of these rocks have hitherto been considered as the base of the Tertiary formation, but in the Waga district along the Okoku railway line, there are many granitic intrusives which show various forms such as irregular masses, dykes and tongues. This paper describes mainly the occurrence, petrographic feature, and chemical property of these intrusives. The writers have been able to distinguish the green tuff to the two formations in this district. One of them is penetrated by granitic rocks and the other covers uncomformably the same rocks. The granitic rocks, occurring in elyke forms are quartz diorites and in irregular masses are granodiorites.

火成岩の風化に關する研究

(1) The volcanogenous soils derived from quartz biotite hornbrende andestic ejecta, which accumulated on the pyroxene andesite soils, basalt soils, soils from tertiary formation, and soils from diluvial series, are widely distributed in Tottori-district. (2) The author studied on the volcanogenous soils at Tomari-mura, Tohaku-gun, and at Kando, Tottori-shi, Tottori Prefecture. The soil profiles studied consisted of yellow or brownish-yellow lower horizon (which the author conveniently calls “yellow horizon”) derived from lapilli, brown B horizon derived either from volcanic sand or from volcanic ash, and dark coloured A horizon derived from volcanic ash. Under the yellow horizon there is reddish-brown pyroxene andesite soil. The humus content in the B horizons was about 2%, and that in the A horizons was about 11%. The B horizons are clayey, and the A horizons are clay-loamy. (3) From the amount of silica and alumina which were dissolved by 10% NaC03 solution, it was recognized that the free alumina contents in the soils were 2_??_4% and that there was no horizon markedly enriched in free alumina. (4) In extracting silica and alumina from the volcanogenous soil with 5% KOH solution, the ratio SiO/Al2O3 becomes constant when the quantity of this solution is larger than 120cc per g of the sample. 5% KOH solution dissolved the free alumina, com-plex A1 (allophane-like substance) almost completely, and complex A2 (halloysitic substance) partly. The volcanogenous soil contains a large amount of silica and alumina, which are soluble in 5% KOH solution, and the ratio SiO2/Al2O3 in this case is very low (0.88_??_1.14). This is a marked characteristics of this soil.

Studies on the Erosion-Volume of the Topography of Yamagata Prefecture

During the cycle of erosion and sedimentation, there should be a volumetric equilibrium between them. The writers have assumed the volume of sediments in basins is equal to the void space between the summit level and the present topography at each drainage area. In that case, the volume of the youngest Tertiary formation (Shibikawa stage of Plioceneage) at Shonai, Shinjo and Yamagata basin is nearly equal to the erosion volume of the topography covered by the Mogami River. In other words, the formation of the present topography has just begun at the latest Pliocene. Further writers found a key to solve the problems to determine the stage of a geomorphological development by analyzing the present topography. Lastly, there is shown a volumetric relation between the river-length (l) and erosion volume (v) in this district, v = 0.019l2 + 0.12l.

On the geology of the Teine mine, with some remarks on the mineral composition and paragenesis of the Mitsuyama, Koganesawa ore deposits

(1) The Teine deposits, once famous for various rarer minerals, occur mainly in the Tertiary formation, called “Green Tuff Group”, which consists of volcanic materials in the forms of lavas and pyroclastics alternating with some mudstone. (2) Most of the veins are believed to have filled up a part of radial fissures around the centre of eruption of propylite, while some veins have a tangential arrangement near the margin of the propylite. (3) The gangue minerals of the Koganesawa deposits are quartz and carbonates, while those of the Mitsuyama deposits are quartz and barite. The former have the lower temperature minerals, such realgar, orpiment, etc. than the later. (4) Luzonite crystallized earlier than enargite, and those minerals are the product of the latest stage of mineralization. The luzonite heated in a electric furnace is no obserbal change to 400°C. (5) The content of Au and Ag has a close connection with quartz, barite and calcite in the upper parts and with tetrahedrite (freibergite), luzonite, enargite in the lower part, where silver minerals are not detected.

Petrogenetic considerations on the lower formations in the oil-fiëld of northeastern Japan (2 nd Report)

1. In the north-eastern environs of Shinjo Basin near Yamagata Akita boundary, there occurs a group of holocrystalline intrusives partly in the granitic base rocks and partly in the lowermost Tertiary formation in this area, the Nozoki Formation which is chiefly composed of volcanic complex as so-called green-tuff formation (Fig. 1). 2. Those rocks in question are mostly dark gray holocrystalline rocks with a kind of dioritic feature as a whole, clearly distinguished from both granitic rocks as basement and the volcanics associated with Tertiary formations, however, they are comparatively rich in change of lithologic facies showing some hypabyssal habits. 3. The constituent minerals are plagioclase, augite and or biotite and hornblende often accompanied by some interstitial quartz and, orthoclase, the latter two being often of micropegmatitic texture (Fig. 3). 4. The coarser and more leucoclatic one, whose plagioclase is Andesine of about 40% in An. contents, corresponds to quartz-diorite or diorite. On the other hand, the finer and more melanoclatic one, whose plagioclase is Labradorite of about 60% in An. contents and mafic is diopsidic augite of about 50° in optic axial angle, has a little quantity of interstitial quartz. The latter corresponds to quartz-gabbro or gabbro.(Tab. 2) The result of the chemical analyses of the typical specimens collected from the main intrusive bodies of these rocks is given in Tab. 3. 5. These holocrystalline rocks may be expected to represent an intrusive member of Tertiary plutonism in relation to the orogenic movement following after the volcanism in the earlier stage of Miocene transgression in inner zone of north-eastern Japan. At any rate, it may be worth to pay attention that these intrusives may have relations not only to the Tertiary igneous activities but also to stratigraphy, tectonic geology and even to metallic ore deposits in Neogene Tertiary formations in north-eastern Japan.

Petroleum Reserves of Japan

The Japanese crude oil production has been steadily declining since 1937, the annual production of the fiscal year 1947 ending March 31, 1948 being 196, 000 kilolitres. It is also reported that about 88% of the total reserves of the proved oil fields owned by the Teikoku Oil Company, which is responsible for more than 90% of the domestic crude oil production, has been already depleted at that date. These circumstances are evidently due to the fact that no new oilpools of appreciable magnitude were discover ed in these years.To establish a sound and comprehensive exploration program embracing oil producing and potential oil producing areas, the Petroleum Exploration Advancement Committee was established in the Mining Bureau of the Ministry of Commerce and Industry, at the instigation of the Natural Resources Section, G. H. Q., S. C. A. P. Under the planning of the Committee, extensive exploration works are now being carried on together with the compilation works to review the existing data.Recent discovery of oil pools of fault trap type, such as at the Ishinazaka and Narahashi oil fields in Yamagata Prefecture, and those of stratigraphic trap type such as at the Shibata and Kaji oil fields in Niigata Prefecture, considerably enwidened the possible area of oil production. Also some structures underneath the alluvial plains in the petroliferous Tertiary basins were newly found by geophysical methods and wait further exploration.In Hokkaido large structures of the Tertiary formation are now being explored, to test the oil possibility of the underlying Cretaceous, which abounds in oil seepages in certain areas of the district.In short, the proved oil reserves of Japan is nearly exhausted, but the possibility of gaining new reserves is growing larger.

Notes on the Geological Age of the Tertiary Formation in the Southern Kii Peninsula

Notes on the Geological Age of the Tertiary Formation in the Southern Kii Peninsula

Description of Lora species from the Tertiary Formation in Isikawa and Toyama Prefectures

Description of Lora species from the Tertiary Formation in Isikawa and Toyama Prefectures