Enhanced evaporation compared to precipitation can lead to increased salinity in lakes, which behave like miniature sea. Short lived population of diminutive sized forams could possibly be introduced in such lakes lying deep and far removed from the sea by seeding or other unknown mechanism. Your suggestions and publication of such lacustrine facies would be highly appreciated.
Dear KMT
Answer to your question is Yes and No ! I am not aware of any flourishing planktic foraminifera in the modern lakes, hence this question. However, my question was specifically posted to solve one strange occurrence of planktic foraminifera in a few centimeter thick intertrappean beds of central India (Jhilmilli section) closely embracing K/Pg boundary and is of basal Danian P1a zone. The assemblage has been analysed and published by Gerta Keller of Princeton University (Keller et al. 2009). Both LM and SEM documentation . No benthic forams or calcareous nannofossils were found. Nearest coeval marine intertrappean beds lie over 800Km away in SE coastal area of India, containing fully marine biotope. Since marine signatures are missing either in the east or west of India, it was hypothesized that essentially in a lacustrine setup of Deccan Volcanic terrain, somehow by seeding or other mechanism planktic foraminifera were introduced to flourish for a short period (For details see Episodes of subaerial Large Igneous Provinces (LIPs) etc...(Jafar, 2015 and references therein at RG). There is some report of benthic foraminifera and dinoflagellate cysts from Middle Miocene of Colombia, nearly 2000 Km away from the sea (Boonstra et al. (2015), X3P, 417, 176-194. Your feedback would be much appreciated.
Dear KMT
Not exactly ! There is no evidence of marine incursion either from the east or west of India. So where did they come from? Any idea? Unless this problem is resolved, scientists would continue to indulge in wild speculations. They can be correlated with P1a zone globally and not only with Danian chalks of Europe.
In Journal of Foraminiferal Research, v. 37, no. 4, p. 318–326, October 2007, FORAMINIFERS FROM HOLOCENE
SEDIMENTS OF TWO INLAND BRACKISH LAKES IN CENTRAL GERMANY, WENNRICH, MENG AND SCHMIED mention in their introduction:"The most diverse non-marine foraminiferal fauna has been reported from Salt Lake, Hawaii, and is comprised of 41 species, including Ammonia tepida and Haplophragmoides wilberti (Resig, 1974). Monospecific populations of Ammo- nia beccarii tepida accompanied by the brackish-water ostracod Cyprideis torosa were recorded from Quaternary sediments and recent water bodies of the Dead Sea area, Israel (Almogi-Labin and others, 1992; Almogi-Labin and others, 1995). Numerous studies have yielded fossil foraminiferal faunas in lacustrine and fluvial deposits from various localities in North Africa, up to 1700 km distant from the ocean (compiled in Le ́vy and others, 1995). These faunas are characterized by the occurrence of Ammonia tepida or A. beccarii, accompanied by specimens of the genera Elphidium, Cribroelphidium, Quinqueloculina and Trichohyalus. A similar faunal composition was reported from recent Lake Qarun, Egypt (Le ́vy, 1984; Abu-Zied and others, 2007) and wells of l’Oued Rhir, Algeria (Gauthier- Lie`vre in Le ́vy and others, 1995). Evidence of non-marine foraminifers from central and western Asia have also been reported, for example, in the Caspian and Aral Seas (Boltovskoy and Wright, 1976), in Lake Balpash-Sor, Kasakhstan (Schmalhausen, 1950) and in water wells in the Kara-Kum desert, Turkmenistan (Brodsky, 1928). Most of these records are linked to Paratethyan relict faunas (Le ́vy and others, 1995). etc ".
No, forams do not grow in fresh water lakes, but in brackish water lakes
Some benthic can live in brackish water but not planktonics, they have requirements that do not allow them to live in such environments. Even in the Mediterranean deposits related to the Messinian salinity crisis there are levels with G. quinqueloba, but they are peseent when periodic marine ingressions occur.
In the article Gennari, G., Rosenberger, T., Spezzaferri, S.*, Berger, J.-P., Fleitmann, D., Preusser, F., Al-Shanti, M., and Matter, A., 2011. Faunal evidence of a Holocene pluvial phase in Saudi Arabia. Journal Foraminiferal Research, 41:3, 248-259.
we found benthic forams far away from the coasts and we speculate about the transport mechanisms. Maybe it can help but I do not see how similar mechanisms can be applied to plankton.
@Francis Hirsch: I believe that in most of the instances where foraminifera have been found in (brackish) lacustrine deposits, these are benthic foraminifera, like Ammonia, right?
In case of the study of Keller et al. (2009), we are talking about planktic foraminifera, taxa such as Parasubbotina, Parvularugoglobigerina and Subbotina. In general, these taxa are considered characteristic for normal marine environments, not stressed, hypo- or hyper saline environments? To me, it seems unlikely that such normal marine taxa occur in a lacustrine environment. Even if the salinity is stable and approximately similar to marine conditions (which already seems unlikely for a saline lake), the conditions still differ immensely from normal marine. If we would be talking about stress-resistant taxa like Guembelitria cretacea, I would consider them possibly in situ, but in this case, a reworked origin seems more likely.
Hellow Colleagues- Francis, Silvia, Johan
Thank you so much for furnishing very important references. I just stumbled upon a reference which has a direct relevance to the problem dealt herein. Both benthic and planktonic foraminifera of Late Coniacian-Santonian age from Songliao Lacustrine Basin of China are documented. Although the results are preliminary, further work on this would help us inch towards the truth.
Syed
Foraminifera fossils of the Late Coniacian-Santonian age documented from Songliao Lacustrine Basin of China have been reported and published. They are associated with calcareous nannofossil, algae and shark tooth, and then are interpeted as records of sea-water incursion.
Hi Xianghui
Extremely happy to get this information. Would you be kind enough to furnish details of the taxa of calcareous nannofossils, algae and shark tooth. Is there any associated remains of Nypa, Cocos, Acrostichum or dinocysts?
Syed
Foraminifera can be transported far inland by birds (link #1). There are some examples of benthic species in continental saline environments (links #2 and #3)
http://link.springer.com/article/10.1023%2FA%3A1007927622654
http://people.rses.anu.edu.au/dedeckker_p/pubs/85.pdf
Conference Paper Re-discovering Entzia, an agglutinated foraminifer from the ...
Sorry, I do not have those as I never do research the topic. I just know the information on the sea-water incursion into the Songliao Basin. Please directly contact the authors in the paper one can donwload.
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