Hitta hit:
T-bana: Universitetet
Frescativägen 40

Ordinarie öppettider:
Tisdag–fredag 11–17
Lördag–söndag 10–18

  • Huvudmeny

History of the investigation of Age and Stratigraphy of the Plant Bearing Formation

Emanuel Swedenborg (1772), Carl von Linné (1751) and Samuel Gustaf Hermelin (1773) were the first to describe profiles from the Scanian coal formation (the Höganäs Formation). However, it was not until 1808 that Vilhelm Hisinger attempted to correlate units within the Scanian coal formation. From the area of Helsingborg he described “flötssandsten" (“seam sandstone") overlaying “the transitional sandstone" and breccia. Moreover, he described coal layers intercalated with the sandstone layers (Hisinger, 1808, Lundgren, 1878). In the beginning of the 19th century various theories on the age and chronostratigraphy were put forward by scientists such as Hausmann, Örsted, Esmarch, Forchhammer, Wahlenberg, and Brongniart. Some theories considered the Scanian coal formation coeval to the Carboniferous coal formations of England and France, other theories considered the age to be either Cretaceous, or more precisely Wealden. These early theories were summarized by Bernard Lundgren (1878).
The collections, work and discoveries by Sven Nilsson (e.g. 1819, 1820a, 1823) laid the foundation for understanding the geology of the Scanian coal formation. In 1819 he recognized the Höör Sandstone, containing fossil plants, as a separate stratum (Nilsson, 1819, 1820a, b). Earlier, it had been considered a part of the “transitional sandstones", e.g., the Hardeberga Sandstone. In 1823 Nilsson described plant-bearing layers at Höganäs, Raus, and Bosarp. To determine the fossils he was assisted by Carl Adolf Agardh and Elias Fries. In the same year Agardh (1823) published his own description of Nilsson´s material. Based on studies of the fossil content Nilsson was convinced that the coal formation was different from, and younger than the Carboniferous coal formations of England and France. In the beginning he thought that the coal formation was of marine origin. However, in the course of a re-examination of his collections it was found that a tooth previously interpreted as a fish tooth actually originated from a crocodile. Also, an insect wing and various molluscs, among which was Avicula inaequivalvis Low, were found in the layers of Höganäs deposits. Based on these findings Nilsson concluded that the coal originated from plants growing close to the area of deposition, and under limnic conditions. Because A. inaequivalvis is a key fossil for the Lower Jurassic (Liassic), the age of the Höganäs Formation could be determined more precisely, and was considered older than and clearly separated from the Höör Formation.
In 1859 Nils Peter Angelin published a geological map of Scania, followed by an explanatory text in 1877, in which he compared European strata from Keuper and Lias with the Scanian strata thought to be Liassic. He recognized the strata underlying the coal formation to be of Keuper age and the coal formation at Höganäs to represent the Triassic-Jurassic transitional beds, so-called Infra Liassic (Bonebed zone, Rhätische Stufe, Avicula contorta zone) (Angelin, 1859/1877). Angelin did not define the stratigraphic position of the Höör Sandstone. Alphonse von Dittmar agreed with Angelin in that at least a part of the Höganäs Formation belonged to the Avicula contorta zone and he considered Nilsson´s Avicula inaequivalvis zone to be Liassic. Von Dittmar was the first who mentioned that both Keuper and Rhaetian, as well as the Liassic were present in Scania (Lundgren, 1878, Dittmar, 1864). Edmond Hébert was the first scientist after Nilsson who made new field investigations and collected material in 1865 and 1869. The identification of this material was carried out by Louis G. de Saporta and Wilhelm P. Schimper. Hébert thought that the coal formation belonged to the same geological system and that it was not possible to distinguish a lower stratum with coal and plants from an upper stratum with marine animal remains, but he agreed with Angelin on the Avicula contorta zone (Lundgren, 1878, Hébert 1869).
Few plant fossils were known at the time, but this radically changed with the work of Alfred Gabriel Nathorst. He described new species from Scania from three different plant-bearing strata, which, in his opinion, belonged to the Rhaetian Stage (Nathorst 1876, 1878a and 1878b). At the same time Bernhard Lundgren investigated and described a number of localities and referred to the works of Nilsson, Hébert and Nathorst. He identified the Avicula contorta zone and a zone with Ammonites planorbis (psilonotus) and Ammonites angulatus. Like Angelin and Hébert he assigned them “Infra Liassic". In contrast, he placed the older flora of Bjuv and the older flora of Höganäs into the Rhaetian, and the younger flora of Höganäs and the flora of Pålsjö into the Lias, based on the investigations by Nathorst (Lundgren, 1878). In 1910 Nathorst presented his conclusions on the 11th International Geological Congress in Sweden. He described 16 plant bearing zones based on his own investigations and the works of Lundgren and Erdmann among others (Nathorst, 1910). Nathorst defined the Rhaetian-Liassic boundary as lying between the Mytilus bed and the zone with Nilssonia polymorpha (Table 1).

Table 1. Principal fossil zones of the Rahetian-Liassic strata of Scania (Nathorst, 1910).

Another to investigate the Scanian stratigraphy was Edvard Erdmann (1872, 1887, 1911-1915), who presented a comprehensive description of the geology and mining techniques at the Scanian coal mines (Table 2).

Table 2. Selection of stratigraphic profiles of the Scanian Coal Formation from a shaft at the Bjuv mine (Erdmann, 1911-1915).

He put the shales, clays and sandstones that lie immediately on the Scanian Silurian systems into the Keuper. Based on petrographic evidence these layers most likely belong to Keuper. Above the Keuper strata follows the coal formation of Scania, which is of Rhaetian-Liassic age. The lower part is generally believed to be Rhaetian and the upper part Liassic, but they are not separated by a clear boundary. The Höör Sandstone is considered a part of the Liassic.

In the middle of the 20th century, Anna Birgitta Lundblad wrote that professor Thore G. Halle “repeatedly pointed out" the need of a complete revision of Rhaetian-Liassic floras of Scania (Lundblad, 1950). Previously, Tom M. Harris (1937) had asked for a “critical revision of the stratigraphy and the specific determinations in the flora". The stratigraphy and the many biostratigraphic zones established by Nathorst and others were, until Gustaf Troedssons investgations, not subject to any major investigations, even though Antevs (1919) and Johansson (1922) pointed out the weakness in Nathorst´s zones. The need for revision was partly redressed by Troedsson (1938, 1940, 1943, 1950, 1951). In a number of publications he gave comprehensive, partly new, conclusions on the stratigraphy of the Rhaetian-Liassic succession of Scania, including chronostratigraphy, delimitation of some lithostratigraphical units (e.g., the Vallåkra Member, the strata of Boserup). Furthermore, he described the cyclic depositional environment linked to transgressions and regressions. In his publication of 1950 he presented a summary of the older Mesozoic strata of Scania (Table 3).

Table 3. Older Mesozoic of Scania (Troedsson, 1950).

Along with Troedsson, Lundblad also contributed to the revisions, presenting descriptions of local floras, including taxonomic revisions, and investigations on the stratigraphy (Lundblad, 1950, 1959). She considered the Triassic-Jurassic boundary somewhere between the upper coal seam and the Boserup beds. Harris (1937) also questioned the many biostratigraphic zones established by Nathorst and others. In addition, he identified two zones in the Scanian Rhaetian-Liassic that he believed to be similar to the Scorseby Sound flora of Greenland (Harris, 1937).

The main features of Troedsson´s scheme (Troedsson 1950) are still a valid framework for the Rhaetian-Liassic stratigraphy of Scania. Improved techniques and continued investigations have shed new light on the question of the age of the plant bearing strata and the question of the Triassic-Jurassic boundary. However, it is very difficult to mark the Rhaetian-Liassic boundary with the lithology only. Biostratigraphic data too, is needed, which is the case for many drilling cores (Sivhed, 1980). In more recent time it has mainly been palynological studies that provided new data (e. g., Norling, 1972, Lund, 1977, Guy-Ohlson, 1981, Guy-Ohlson and Norling, 1994). Ulf Sivhed summarized current opinions on the Rhaetian to Middle Jurassic in Scania, with references to the works of Nilsson, Angelin, Lundgren, Nathorst, Erdmann, Troedsson, and Lundblad (commented on above). Sivhed (1984) also referred to more recent works of Edmund Bölau, 1949, Hans Tralau, 1975, Jens Lund, 1977 and Dorothy Guy-Olsson, 1981. Beside the summary of Sivhed there are older summaries by Nathorst (1876), Lundgren (1878), Troedsson (1943, 1950) and Lundblad (1946). Most recent, a comprehensive overview was given by Norling et al. (1993) in the “Guide to the Upper Triassic and Jurassic geology of Sweden". A stratigraphic scheme is presented in Table 3 (Sivhed, 1984). Today, the Triassic-Jurassic boundary seems to be undisputed lying between the Bjuv Member and the Helsingborg Member.

Agardh, C. A., 1823. Närmare bestämmande af några Vextaftryck funne uti Höganäs Stenkolsgrufvor. Kongl. Vetenskapsakademiens Handlingar 1823: 106-112.

Angelin, N. P., 1859 (map), 1877 (text). Geologisk Öfversigts-karta öfver Skåne. Ph. Lindstedt. Lund.

Antevs, E., 1919. Die Liassische flora des Hörsandsteins. Kungliga Svenska Vetenskapsakademiens Handlingar 59(8): 1-71.

Bölau, E., 1949. Berggrundstudier i trakten av Höganäs. Geologiska Föreningens i Stockholm Förhandlingar 71(3): 383-412.

Dittmar, A. von, 1864. Die Contorta-Zone (Zone der Avicula contorta Portl.) : Ihre Verbreitung und ihre organischen Einschlüsse. H. Manz. Münich. P9. 217p.

Erdmann, E., 1872. Beskrifning öfver Skånes Stenkolsförande Formation. Sveriges Geologiska Undersökning C 3. 87pp.

Erdmann, E., 1887. Beskrifning öfver Skånes Stenkolsfält och gruvor. Häfte 1. Sveriges Geologiska Undersökning C 65. 124pp.

Erdmann, E., 1911-1915. De skånska stenkolsfälten och dess tillgodogörande. Geologisk och tekninsk beskrivning. Sveriges Geologiska Undersökning Ca 6. 548pp.

Guy-Ohlson, D., 1981. Rhaeto-Liassic palynostratigraphy of the Valhall bore No. 1, Scania. Geologiska Föreningens i Stockholms Förhandlingar 103(2): 233-248.

Guy-Ohlson, D and Norling, E., 1994. Jurassic sequences in Sweden. Geobios, M. S. 17: 275-286.

Harland, W B., Armstrong, R. L., Cox A. V., Craig, L. E., Smith, A. G. and Smith D. G., 1990. A geologic time scale 1989. Cambridge University Press. Cambridge.

Harris, T. M., 1937. The fossil Flora of Scoresby Sound East Greenland. Part 5. Stratigraphic relations of the plant beds. Meddelelser om Grønland 112 (2): 82-86.

Hébert, M., 1869. Recherches sur l´âge des Grés á combustibles d´Helsingborg et d´Höganäs. Annales des Sciences Géologiques 1(2). 37pp.

Hermelin, S. G., 1773. Anmärkningar om Boserups stenkols-grufva och de öfrige stenkols-försök uti Skåne. Kungliga Svenska Vetenskapsakademiens Handlingar 34.

Hisinger, W., 1808. Samling till en mineralogisk Geografi öfver Sverige. 254 and 264 cont. H. A. Nordström. Stockholm.

Johansson, N., 1922. Die rätische flora der Kohlengruben dei stabbarp und skromberga in schonen. Kungliga Svenska Vetenskapsakademiens Handlingar 63(5): 1-78.

Linné, C. von, 1751. Carl Linnaei Skånska resa, på höga öfwerhetens befallning förrättad år 1749. Med rön och anmärkningar uti oeconomien, naturalier, antiquiteter, seder, lefnads-sätt. Med
tillhörige figurer. Med kongl. Maj:ts allernådigste privilegio, uplagd på Lars Salvii kostnad 1751. Stockholm.

Lund, J., 1977. Rhaetic to Lower Liassic palynology of the onshore south-eastern North Sea Basin. Danmarks Geologiske Undersögelse. Raekke 2: 109. 128pp.

Lundblad, B., 1946. De sista 35 årens bidrag till kännedomen om Sveriges mesozoikum. Geologiska Föreningens i Stockholms Förhandlingar 68(2). 251-267.

Lundblad, B., 1950. Studies in the Rhaeto-Liassic floras of Sweden 1. Kungliga Svenska Vetenskapsakademiens Handlingar 1(8): 2-82.

Lundblad, B., 1959. Studies in the Rhaeto-Liassic floras of Sweden 2:1. Kungliga Svenska Vetenskapsakademiens Handlingar 6(2): 1-38.

Lundgren, B., 1878. Studier över faunan i den stenkolsförande formationen i nordvästra Skåne. Kongl. Fysiografiska Sällskapets Minnesskift 1878: 1-58.

Nathorst, A. G., 1876. Bidrag till Sveriges fossila flora. Växter från rhätiska formationen vid Pålsjö i Skåne. Kungliga Svenska Vetenskapsakademiens Handlingar 14(3). 82pp.

Nathorst, A. G., 1878a. Beiträge zur fossilen Flora Schwedens. Über einige rhätiche Pflanzen von Pålsjö in Shonen. E Schweizerbart´sche Verlagshandung (E. Koch). Stuttgart. 34pp.

Nathorst, A. G., 1878b. Om floran i Skånes kolförande bildningar 1. Floran vid Bjuf, första häftet. Sveriges Geologiska Undersökning C 27: 1-52.

Nathorst, A. G., 1910. Les dépôts mésozoïques précrétacés de la Scanie. 11th International Geological Congress in Sweden: Excursion C6. 46pp.

Nilsson, S., 1819. Beskrifning öfver en petrikatförande sandsten vid Hör i Skåne. Kungliga Svenska Vetenskapsakademiens Handlingar 1819.

Nilsson, S., 1820a. Om försteningar och aftryck af tropiska trädslag och deras blad, funne i ett sandstenslager i Skåne. Kongl. Svenska Vetenskapsakademiens Handlingar St. II. a: 108-122.

Nilsson, S., 1820b. Om försteningar och aftryck af tropiska trädslag, blad, ormbunkar och rörväxter m. m. samt trädkol funna i ett sandstenslager i Skåne., Kongl. Svenska Vetenskapsakademiens Handlingar St. II. b: 277-285.

Nilsson, S., 1823. Underrättelse om några petrificater, fundna i den Skånska Stenkols-formationen. Kongl. Svenska Vetenskapsakademiens Handlingar 1823: 95-106.

Norling, E., 1972. Jurassic stratigraphy and foraminifera of western Scania, southern Sweden. Sveriges Geologiska Undersökning Ca 47. 120pp.

Norling, E., Ahlberg, A., Erlström, M. and Sivhed, U., 1993. Guide to the Upper Triassic and Jurassic geology of Sweden. Research paper. Sveriges Geologiska Undersökning Ca 82. 71pp.

Sivhed, U., 1980. Lower Jurassic Ostracodes and Stratigraphy of western Skåne, southern Sweden. Sveriges Geologiska Undersökning Ca 50. 61pp.

Sivhed, U., 1984. Litho- and biostratigraphy of the Upper Triassic-Middle Jurassic in Scania, southern Sweden. Sveriges Geologiska Undersökning C 806: 1-31.

Swedenborg, E., 1722. Miscellanea observata circa res naturales & praesertim circa mineralia, ignem & montium strata. Leipzig. 174pp.

Tralau, H., 1975. An Upper Triassic microflora from Vallåkra, southern Sweden. Geologiska Föreningens i Stockholm Förhandlingar 97(3): 237-242.

Troedsson, G., 1938. On the Sequence of strata in the rhaetic-Liassic beds of Scania. Geologiska föreningens i Stockholm förhandlingar 60(3): 547-550.

Troedsson, G., 1940. Om Höörs sandsten. Geologiska Föreningens i Stockholm Förhandlingar 62(3): 245-283.

Troedsson, G., 1943. Om gränsen mellan rät och lias i Skåne. Geologiska Föreningens i Stockholm Förhandlingar 65(3): 271-284.

Troedsson, G., 1950. Om lagerföljden inom Sveriges äldre mesozoikum. Meddelelser fra Dansk Geologisk Forening 11(5): 595-597.

Troedsson, G., 1951. On the Höganäs Series of Sweden (Rhaeto-Lias). Skrifter från Mineralogisk- och Paleontologisk-Geologiska Institutionerna, Lund: 7. 269pp.

Text: Ove Johansson