Diplocraterion

Diplocraterion
Diplocraterion burrow (at left) from the Silurian-age Tuscarora Formation at Bald Eagle Mountain, Centre County, Pennsylvania. Specimen is ~22cm high.
Trace fossil classification Edit this classification
Ichnogenus: †Diplocraterion
Sketch by Richter (1926) showing spreite in a Diplocraterion parallelum burrow.

Diplocraterion is an ichnogenus describing vertical U-shaped burrows having a spreite (weblike construction) between the two limbs of the U.[1][2] The spreite of an individual Diplocraterion trace can be either protrusive (between the paired tubes) or retrusive (below the paired tubes).[3] Some ichnospecies have both types (e.g., Diplocraterion yoyo).[4] The presence/absence of funnel-shaped openings should not be used as an ichnotaxobase due to the high probability that the upper portions of the trace may have been eroded away.[2] Observation of the orientation of Diplocraterion in the field is frequently used to determine the way up of rock strata at outcrop.[5]

There are several ichnospecies of Diplocraterion.

Some Ichnospecies of Diplocraterion
Ichnospecies Diagnosis
D. parallelum[6] Parallel burrow walls and unidirectional spreite[6][2]
D. helmerseni[7] U-tubes expand laterally at the base[7][2]
D. biclavatum[8] Arms of the U-tube extend below the curved base and form blind pouches[8][2]
D. habichi[9] Arms of the U-tube diverge upward[9][2]
D. polyupsilon[10] Bidirectional spreite that constrict upward[10][2]
D. yoyo[4] U-tubes with both retrusive and protrusive spreiten[4]
  1. ^ Cite error: The named reference richter1926 was invoked but never defined (see the help page).
  2. ^ a b c d e f g Cite error: The named reference Fursich1974 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Cornish1986 was invoked but never defined (see the help page).
  4. ^ a b c Goldring, Roland (1962). "The trace fossils of the Baggy Beds (Upper Devonian) of North Devon, England". Paläontologische Zeitschrift. 36 (3–4): 232–251. Bibcode:1962PalZ...36..232G. doi:10.1007/BF02986976. S2CID 140161473.
  5. ^ "Determining stratigraphic tops". Geological digressions. 6 February 2019. Retrieved 19 January 2020.
  6. ^ a b Torell, O., 1870. Petrificata Suecana Formationis Cambricae. Lunds. Univ. Arsskr. 6. Avdel. 2, No. VIII, p. 1-14.
  7. ^ a b Opik, A., 1929. Studien uber das estnische Unterkambrium (Estonium). I-IV. Acta Comment. Univers. Tartuensis, A. 15(2), 56 p.
  8. ^ a b Miller, S.A. (1875). "Some new species of fossils from the Cincinnati group and remarks upon some described forms". Cincinnati Quarterly Journal of Science (2): 349–355.
  9. ^ a b Lisson, C.I., 1904. Los Tigillites del Salto del Fraile y algunes Sonneratia del Morro Solar. Cuerpo Ingen. Minas del Peru, Bol No 17, 64 p.
  10. ^ a b Smith, J. (1893). "Peculiar U-shaped tubes in sandstone near Crawfurdland Castle and in Gowkha Quarry, near Killwinning". Transactions of the Geological Society of Glasgow (9): 289–292.