A chemical method for extracting calpionellids from indurated calcareous rocks

Duchamp-Alphonse, Stéphanie; Fiet, Nicolas; Pagel, Maurice; Remane, Jürgen
March 2009
Micropaleontology;2009, Vol. 55 Issue 1, p87
Academic Journal
Indurated calcareous rocks often offer opportunities to date and examine local palaeoenvironmental conditions from the analysis of included microfossils. While most microfossils provide valuable biostratigraphic information through thin section analysis alone, diagnostic and palaeoenvironmental information typically require free specimen observations. A range of extraction techniqnes are well documented for the commonly encountered robust microfossils (foraminiferas, ostracods...), but a method is still missing for the delicate calcareous groups. This paper presents a method for extracting calpionellids from highly indurated ca.lcareous rocks. This method is based on the use of chlorhexidine and benzalkonium chloride. These compounds form complexes with the matrix of calcareous material and render it soluble. The technique is easy, quick, economical, and produces reliable results. Importantly, for the first time it allows the observation of the delicate external morphology of calpionellid specimens using a scanning electron microscope (SEM). This may prove to be helpful in better defining the taxonomic position of this group of organisms and might also be useful in determining their palaeoecological affinities. This technique might also prove applicable for other delicate groups.


Related Articles

  • Deciphering hieroglyphs--Tracks and trails in rocks. Romano, Mike // Journal of Biological Education (Society of Biology);Spring94, Vol. 28 Issue 1, p27 

    Discusses the study of trace fossils or hieroglyphs in rocks, as an important branch of paleontology. Interpreting the former behavioral activity of extinct organisms; Uses of hieroglyph studies in sedimentological, stratigraphical and paleogeographical studies.

  • Glauconitic deposits at JulegÃ¥rd on the south coast of Bornholm, Denmark dated to the Cambrian. Clemmensen, Lars B.; Bromley, Richard G.; Holm, Paul Martin // Bulletin of the Geological Society of Denmark;2011, Vol. 59, p1 

    Bioturbated, glauconitic siltstones and sandstones are overlain by presumed Upper Triassic deposits at coastal exposures at Julegård on the south coast of Bornholm. These glauconitic deposits have not previously been dated. A 40Ar-39Ar dating of the glaucony gives an age of 493 ± 2 Ma...

  • Why so few dinosaurs? RICH, THOMAS H. // Australian Geographic;Sep/Oct2014, Issue 122, p41 

    The article focuses on the scanty success of finding dinosaur fossils in Australia, but there is a unique opportunity for discovery in the region as Australian topography is both flat and ancient. In outback New South Wales and South Australia, isolated bones are found in the opal fields, and...

  • A cautionary note on the use of invertebrate trace fossils for correlation in the Triassic-Jurassic Fundy Group. MACNAUGHTON, ROBERT B.; PICKERILL, RON K. // Atlantic Geology;2010, Vol. 46, p90 

    Red-bed strata generally considered to be of Triassic age are present in outcrop at Point Lepreau and St. Martins, New Brunswick. These successions preserve assemblages of invertebrate trace fossils that are similar to one another. Some authors have taken this as evidence that the successions...

  • Trace fossils from Talchir carbonate concretions, Giridih basin, Jharkhand. Das, S. S.; Tripathi, Mahesh Kumar // Journal of Earth System Science;Feb2009, Vol. 118 Issue 1, p89 

    The carbonate concretions occurring at the bottom of Talchir fissile shale facies preserved signatures of various trace fossils along with a cast of doubtful organisms and cyanobacterial mat structures. The host shale deposited under glacial melt water fed lacustrine condition. The concretions,...

  • Neoichnology of Thyonella gemmata: A Case Study for Understanding Holothurian Ichnofossils. Smilek, Krista R.; Hembree, Daniel I. // Open Paleontology Journal;2012, Vol. 4, p1 

    While the fossil record of holothurians extends from the Cambrian to the Holocene, adequately evaluating their temporal and spatial distribution is difficult due to their poor preservation potential. Several extant holothurians, however, produce abundant shallow burrows that a have a high...

  • Fossil Facts. Geiger, Beth // National Geographic Explorer;Apr2008, Vol. 7 Issue 6, p12 

    The article offers information about fossils. Fossils are the remains of plants or animals from long ago. They come in every shape and size. Many fossils were once animals that lived in a lake or ocean. After the animals died, their bodies sank to the bottom. Mud or sand covered the remains....

  • Microfósseis do Grupo das Beiras (Monfortinho - Salvaterra do Extremo, Beira Baixa, Portugal Central). Sequeira, António J. D. // Comunicaçõe Geológicas;Jan2011, Vol. 98 Issue 8, p55 

    Following the discovery of several microfossils in the region of Coria (Spain) (Liñán & Palacios, 1987; Palacios, 1989), a sampling campaign was made in the Monfortinho - Salvaterra do Extremo region (Central Portugal), during August of 1987, to verify their presence in the Portuguese...

  • Paleo-Environmental Significance of Ichnofossils from the Babaguru Formation of the Cambay Basin, Gujarat, India. Mude, Shyam N. // Universal Journal of Environmental Research & Technology;Feb2012, Vol. 2 Issue 1, p52 

    Ichnofossils are biogenic structures preserved on or within the substrate by an organism during their various movements such as dwelling, feeding, resting etc. Ichnofossils are widely used for the interpretation of the paleo-environment of the sediments / rocks. The present paper documents four...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics