Sunday, March 23, 2014

Globigerina Ooze from the H.M.S. Challenger Expedition ~ Not Moon Rocks

The H.M.S. Challenger (a British sailing vessel with an auxiliary motor) spent March 21, 1875, at latitude 7o 45' N and longitude 144o 20'  E, just to the west of the Caroline Islands in the western Pacific.  The ship, in the third year of its epic voyage of scientific discovery, would not return to England until May, 1876.  (The picture of the ship is from Report of the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-76.  Narrative, Volume 1, First Part, 1885, p. 1.)

On this particular day, the Royal Navy seamen and the group of civilian scientists on board (called “the scientifics” by the crew) performed the same grueling tasks that they had performed with monotonous regularity since the beginning of the voyage.  In doing so, they were fulfilling the expedition’s charge from the British government and the Royal Society of London – explore the biological, chemical, and other physical attributes of the world’s oceans.  A specially equipped line was let down to determine the depth of the ocean at this specific location or “station,” measure the temperature at different depths, secure water samples at different depths, and recover a small sample of the bottom material.  In addition, a more substantial sample of fauna was collected from the bottom by means of dredging (at many stations,  trawling was used to secure this sample).  All of this made up a daylong process that required the ship to run its auxiliary engine (thereby burning scarce fuel) in order to remain at station and drag the dredge or trawl across the bottom.  On this day, the Challenger worked station 224.

(I've marked the location of station 224 with an arrow.  I realize that it's difficult to read this chart in this post.  This and other Challenger charts in much more readable size have been placed online by the University of Kansas Natural History Museum.  The section shown above is from chart 31.)

I wrote about the importance of the Challenger expedition from 1872 to 1876 in a previous post in which I reviewed Richard Corfield’s superb book titled The Silent Landscape:  The Scientific Voyage of HMS Challenger, 2003.  The book remains my primary resource on things Challenger.

In the first months of 1875, the Challenger, which had been in Hong Kong for nearly all of the last two months of 1874, sailed to the Philippines, New Guinea, and then the Admiralty Islands.  Of the present leg of its voyage which included station 224, Challenger scientist Henry Nottidge Moseley wrote, “The Admiralty Islands were left behind on March 10th, and a most tedious voyage, of a month’s duration, to Japan ensued.”  (Notes by a Naturalist.  An Account of Observations Made During The Voyage of H.M.S. “Challenger” Round the World in the Years 1872-1876, 1892, new and revised edition, p. 416.)

Among the data collected that day:  the ocean bottom lay 1,850 fathoms (2.1 miles) below the ship, it was 1.3o C (34.3o F) at the bottom, and the dredge came up full of Globigerina ooze.  (This information from station 224 appears in “Challenger” Expedition.  List of Observing Stations, Printed for the Use of the Naturalists Engaged in Preparing the Account of the Voyage, by C. Wyville Thomson, 1877, p. 40.)

Globigerina ooze.  Savor the phrase . . . just the phrase, not ooze, but this is such an evocative name, wonderfully capturing the essence of this muck.  The ooze is composed largely (by definition, at least 30 percent) of shells from foraminifera (single-celled protozoa) of the planktic Globigerinidae family.  The shells, the mineral remnants of dead foraminifera, slowly drift down through the water column and collect on the sea floor in staggering amounts.  The resultant calcium carbonate ooze today covers some 130 million square kilometers of the ocean floor; it is one of the planet’s principal ocean sediments, present generally at low and mid latitudes, and at depths from roughly 400 fathoms (2,400 feet) down to about 2,200 fathoms (2.5 miles) at which point the acid level of the water works to dissolve calcium carbonate shells.  Below those depths and in high latitudes, Radiolarian ooze is likely to predominate; this ooze is composed primarily of the siliceous skeletons of radiolaria (single-celled, planktic protozoa).  (Corfield, Silent Landscape, p. 62-63; John O. E. Clark and Stella Stiegelier, The Facts on File Dictionary of Earth Science, 2000, p. 147.)

The Globigerina ooze is often white, but the color can change depending upon depth and the inorganic materials in the mix.  The ooze from station 224 had “a slight rose tinge” and, when dry, was “almost white . . ., slightly coherent, friable, chalky, earthy.”  This description of the ooze at station 224 comes from the Report on Deep-Sea Deposits Based on the Specimens Collected During the Voyage of H.M.S. Challenger in the Years 1872 to 1876, by John Murray (one of the scientifics) and geologist A.R. Renard (1891, p. 108).  (I’m not sure what “coherent” means in this context.)

Murray and Renard’s volume contains some incredibly beautiful plates of the faunal remains that the expedition collected from the deep sea.  One particularly striking figure (Plate XI, figure 5) shows the composition of Globigerina ooze (after a bit of washing) from station 13 in the North Atlantic from a depth of 1,900 fathoms (2.2 miles).  The authors noted that the material shown “consists chiefly of various species of pelagic Foraminifera, together with a few fragments of worm-tubes, Pteropods, and Ostacode valves.”  (Pteropods are planktic snails and ostracodes are crustaceans that live inside two hinged tests.)

Among the Globigerinidae foram shells that made the reverse trip from ocean bottom to the surface on March 21, 1875, at station 224 were many from the foraminifera called Sphaeroidinella dehiscens (Parker and Jones, 1865) (this foraminifera was known as Sphaeroidina dehiscens at the time).  A small sample of those recovered by the Challenger that day in March, 1875, is shown below, mounted (well, most of them remain mounted even after the passage of so much time) in an antique microscope slide from the period.

These particular specimens may not be very old.  As the ocean floors move away from the mid-ocean ridges (where the floor material is created), toward the edges of the ocean basins, they can, over millions of years, accumulate a deep covering of Globigerina ooze.  Richard Corfield writes, “In fact, the oldest sediment occurs at the far western edge of the biggest ocean basin of them all, the Pacific.  In this region the deepest sediment is 200 million years old – an age that places it firmly in the middle of the Jurassic period of Earth history.”  (The Silent Landscape, p. 138)  The S. dehiscens shells shown above are of more recent vintage since the species itself seems to have evolved only some 3 million years ago in the Pliocene epoch.  (Evolutionary Changes in Supplementary Apertural Characteristics of the Late Neogene Sphaeroidinella dehiscens Lineage (Planktonic Foraminifera), Bjorn A. Malmgren, et al., Palaios, 1996, Volume 11, p. 192-206.)

Nevertheless, these foraminifera shells exude a gravitas for me that far surpasses whatever significance I might attach to them because of their age.  These very shells were lifted from the Pacific Ocean 139 years ago by the men of the HMS Challenger.  They are simply amazing because of their connection to this historical voyage.  And there is also the remarkable fact that I own them and have them here before me, encased on a slide.

Well, wait, perhaps it’s not so remarkable that they have come into my possession because many, many people have Challenger specimens and these days they still frequently show up on eBay.  But, how did that happen?  After all, weren’t these specimens collected during an ocean expedition financed by the British government and conducted with a vessel of the Royal Navy staffed by Navy officers and crew?  Why didn’t they remain the property of the British Government like, say, the moon rocks brought back by the Apollo astronauts which are the property of the U.S. government?

The Challenger microfauna very quickly escaped from the scientifics and the other scientists enlisted in the production of the 50 volumes of official reports which took some 20 years to complete.  The sheer number of people involved is one key.  That’s certainly Peter B. Paisley’s hypothesis about the relatively quick appearance of Challenger specimens in the hands of the general public:  “With so many involved in analysis of the Challenger results, ‘leaking out’ of material for mounters was well-nigh inevitable.”  (Aquatic Life and British Victorian Microscopy, Micscape Magazine, October 2010.)  More importantly, the number of microfauna specimens hauled in with just a single passage of the dredge bordered on the countless.  So vast numbers of Challenger foraminifera and radiolaria and other specimens could disappear and no one would be the wiser, and the research would be unlikely to suffer.  In contrast, Apollo moon rocks remain preciously rare and so it’s not beyond the realm of possibility to keep control of all of them, enforcing governmental ownership, in a way decidedly impossible with the microscopic fauna brought home by the Challenger.  But, apparently even the former may be a challenge, since NASA has had a less than stellar record of keeping track of the Apollo moon rocks.  (See, for example, The Misplaced Stuff:  NASA Loses Moon, Space Rocks, by Seth Borenstein, The Boston Globe, December 8, 2011; and NASA’s Management of Moon Rocks and Other Astromaterials Loaned for Research, Education, and Public Display, NASA Office of Inspector General, Report No. IG-12-007, December 8, 2011.)

At least, there isn’t a public marketplace involving the sale, purchase, and exchange of Apollo moon rocks like the one that almost immediately sprang up for microscope slides with mounted Challenger specimens.  By 1879, a popular science journal like Hardwicke’s Science-Gossip was running in its Exchanges column the following ads (Volume XV, Number 173, p. 120):

Wanted, good slides, in exchange for well-mounted slides of “Challenger” sounding. – H.R. 85 Worcester Street, Higher Broughton, Manchester

Good slides of diatom and globigerine ooze (“Challenger” dredging); also parasite from gill of salmon, in exchange for other good slides. – Nicholas Wright, 8 Duke Street, Lower Broughton, Manchester

Two days after quitting station 224, HMS Challenger had sailed to station 225, and the excruciatingly dull voyage to Japan was enlivened by what the scientifics discovered there on March 23, 1875.  The line went out and out . . . and still out some more, until a depth of 4,575 fathoms (5.2 miles) was recorded, the deepest point measured during the entire voyage.  (This area is called the Challenger Deep and is known to be nearly 7 miles deep.)  No Globigerina ooze that day; instead, Radiolarian ooze emerged from the bottom.


In his comment (see below), Howard mentioned Henry B. Brady's report on the Challenger foraminifera and the truly marvelous drawings that appear there.  Here is one that shows a couple of shells from S. dehiscens.  This is just a portion of the full plate (LXXXIV) on which these shells appeared.  I made this photograph from the original 1884 publication (Report on the Foraminifera Collected by H.M.S. Challenger During the Years 1873-76, Zoology, Part 22, two volumes - plates are in the second volume); this specific volume is one held in the Smithsonian's natural history library.  Looking at this volume was quite a treat.  All of the plates can be seen at the 19thcenturyscience website.


  1. Nice post. I'm a big fan of Brady's Challenger forams volume, which was reprinted in 1960 by the SEPM; copies--though rare--are sometimes found in used book sales (not by me, I'm sorry to say).

    "More importantly, the number of microfauna specimens hauled in with just a single passage of the dredge bordered on the countless. So vast numbers of Challenger foraminifera and radiolaria and other specimens could disappear and no one would be the wiser, and the research would be unlikely to suffer."

    My own experience leads me to think that may be the case. I don't know how much sediment was collected at each Challenger station, but probably vastly more than needed for their purposes. It doesn't take much. I was the wellsite geologist on an oil exploration well in Central America, back in the '80s. We were directed to collect two vials of cuttings at each sample depth. One vial was archived for posterity, the contents of the second were to be pulverized in a mortar and pestle and used for a calcimetry test (to determine the fractional volume of calcium carbonate in the sample). The calcimetry test only used a fraction of the vial contents, so rather than toss the rest--about a thimbleful--into the sump, I would pick through the "discard" fraction for forams, of which there were often many.


  2. Howard:

    Thanks so much for your comment. I had several photographs of Brady's illustrations of the foraminifera in question and just added one to the post. They are really quite beautiful, even (I suspect) to those not into forams and other microfauna.

    I have begun to research that issue of how much in the way of specimens from the ooze the "scientifics" actually brought back from the voyage. (It's something I should have tackled before uploading the post, but I wanted to get it online by March 23rd.) I have some of the dimensions of the trawling and dredging equipment and I think they are large enough to have pulled up foram shells in probably the hundreds of thousands in any productive pass. (The abundance of the microfauna is staggering. Case in point, I've collected over 6,000 fossil ostracode shells from a small jar of Cretaceous matrix.) Donald Prothero in Bringing Fossils to Life (1998) writes that the ooze can have a foram density that "exceed[s] more than a million specimens per square meter of sediment." (p.190) I'm not quite sure what to make of that estimate, partly because I suspect he really meant per "cubic meter," and that's actually a lot of material.

    Anyway, the scientifics had arrangements of stacked sieves on deck which allowed them to separate the ooze on the spot, keeping and rejecting specimens as they looked through the material in the various sieves. The reports of the voyage documented and quantified everything, so why not some measure of what was brought back to England in the way of microfauna? I'll keep looking.


  3. Tony--

    I suspect Prothero really did mean one million per *square* meter. Doing the math, one square meter is 1000 x 1000 mm = 1 million square mm. Given that a lot of forams are much smaller than 1 mm, it's not unreasonable that a very rich deposit could have more than a million specimens per square meter of the sediment surface (essentially, the entire surface covered with forams). A cubic meter of sediment is a lot of dirt, and a million forams wouldn't be much by comparison. Perhaps "per square meter of sediment" is just sub-optimum wording, and should have read "per square meter of the sediment surface".


  4. Yes, your logic certainly holds, which means a staggeringly huge number of forams and the like would have been collected during the voyage (though not necessarily stored away on board the ship).


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