Fossil Sponge Devonian Solid Chert Onondaga Limestone Fossil 100% Intact 390 MYO

Description

Fossil Sponge Devonian Onondaga Limestone
Solid Chert Fossil Sponge.
(Flint) Fossil Sponge Sponges
Preserved 100% Intact
390 Million Years Old.
Glacial Erratic Paleozoic (Devonian) Chert Fossil Sponges
(Porifera: Demospongea with Excellent 3D Preservation)
From Glacial Drift and Lakeshore Deposits on Lake Erie
In Western New York USA and Southern Ontario Canada.
My fossil sponges come from the surface bedrock exposures of the Onondaga Limestone that occur in southern Ontario Canada, under Lake Erie, and in Western New York.  They have been liberated from the bedrock by repeated cycles of Ice Age glaciation as well as 390 million years of uplift and erosion and and weathering and concentration of these indestructible solid chert fossils in glacial and lakeshore deposits.
PREPARATION:
Repeated soakings in hydrochloric acid followed by repeated scrubbings with detergents.  These solid chert fossils are largely indestructible and hold up to 50% HCl baths for days at a time. Many detergent scrubbings between acid baths.  A final coating of detergent (Dawn) is spread over most fossil surfaces to bring out details, to further loosen matrix particles during dormancy or in transit, and unlike paints and glues and oils, it can easily be scrubbed off with hot water (It's only Soap!)  I leave a light coating of Dawn on most of my fossils and museum specimens to bring out surface details.  Wash off and/or reapply at your pleasure.
HOW OLD?
According to Wikipedia:
Relative
age
dating of the
Onondaga
places its formation in the Eifelian to Givetian stage of the Middle Devonian period, or 391.9 to 383.7 Ma. Radiometric dating of a sample from the bentonite at the top of the
Onondaga
placed it at 390 ± 0.5 Ma.
Overlies:
Helderberg Group
,
Old Port Formation
,
Named for:
Onondaga, NY
Underlies:
Hamilton Group
and Marcellus Formation.
KEYWORDS: fossils rocks minerals shells sponge fossil sponges biology geology science teaching education fossils.
Sponges…
Diverse, Abundant, Practically Immortal,
Well-Preserved, Beautiful, & Everywhere!
For Half A Billion Years.
And they can Morph !
Meet the Sponges...
If you plan on becoming a Marine Biologist, a Zoologist, an Oceanographer, a Paleontologist, or just getting through a entry level course in college Zoology... You will need to know these things in both your education and in your work. Sponges Rock !
Sponges are among the most evolutionarily successful phyla of multicellular organisms on Earth. They are much more abundant in the fossil record than many misinformed paleontologists and biologists are willing to admit because they just do not yet know.  But They Will Now!
Sponges along with much-easier-to-identify corals have been the dominant life form on reefs and both deep and shallow ocean bottoms for more than 600 million years.  Sponges occupy niches in almost every marine ecosystem, have done so since Precambrian times, and still do. It should be no surprise that their fossil remains are just as common as corals and perhaps even more so once we are able to identify them clearly and properly.
Many of the things that Science has erroneously identified as "nodules" and "concretions" and "just chert" for generations are, in fact, Sponges.
Sponges, the members of the phylum Porifera (meaning "pore bearer"), are the basal-most clade of animals, as sister of the diploblasts. They are multicellular parazoan organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells. Sponges have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. Sponges do not have nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes.
My current research is constructing a flow chart of features common in fossil sponges and which can be used for the general identification of fossil sponges in marine sedimentary rocks.
One of the identification features I have observed is what I call the Tree Of Haeckel. The "tree" is the Flagellated Choanocyte (Collar Cell) channels and water current flow system in sponges. Haeckel depicted it brilliantly in several of his highly stylized and idealized depictions of sponges and other marine creatures.
Ten common features to watch for in answering “Is It A Sponge?"
·
Incurrent Pores, Excurrent Pores, Oscular Cavities and flagellated canals are well-preserved and are evident in most living sponges and in sponge fossils.
·
Chert present.  Most Chert is formed from silicate sponge spicules.
·
“Haeckel's Tree” Branching spicule-supported system of flagellated canals.
·
Hexagons.  Roughly hexagonal shape of many structural growth features is apparent.
·
Cloverleafs. Roughly cloverleaf shaped structural growth features occur in many sponges.
·
Iron Crosses.  Many sponges have rough iron cross shaped growth features evident.
·
Discoid (coin-like) structural marks, attachment points, and basal scars.
·
Tip-over.  Sponges are adapted for “Tip-over” damage control… a “Plan B”.
·
Balance.  Sponges are adapted for Balance.  Fossil sponges retain that balance.  One can recount the life history and chronology of living and fossil sponges recorded in their morphology similarly to studying and ascertaining cross-cutting relationships in general geology.
·
Basalia or Basal Aster.  The original orientation of sponges about their points of origin (basalia) and from which they grow a basal prosopore and flagellated choanocyte canals in a general ever-upward direction, which is recovered following a tip-over event.
Sponge Characteristics:
Some Common Characteristics of Sponges and Sponge Fossils:
--   Sponges have overall cup-like or bottle-like or vase-like vertical shapes OR flattish discoidal or mound-like horizontal shapes.
--   Incurrent Pores appear as circles, dots, lumps, bumps, and nodules on external surfaces.  Pyrite minerals are quite common in the taphonomy of sponges.
--   Many vertical sponges have wide top oscular openings showing sediment infilling; and occasionally but rarely show open internal structure of the oscular cavity due to sediment infilling.
--   Sediment-filled oscular cavities are often capped by epifauna such as corals weathering /eroding to "sponge plugs".
--   Some sponges have very narrow excurrent oscular openings or excurrent pores resembling a blowhole or volcano shape in gross morphology.
--   Discoidal horizontal growth forms are replaced by elongate vertical forms when environmental conditions are right.
--   Flat horizontal lateral discoidal growth is a common default growth habit in many species.
--   Tipped over vertical sponges may adopt the horizontal growth mode as damage control under certain environmental conditions.
--   Right angle vertical branches are common damage control and regrowth adaptations following tipover.
--   Both growth modes are evident in some larval sponges, which adapt and develop according to environmental conditions… how they first land… flat or upright.
--   Tall vertical columnar growth toward the Sun is often a "preferred" morphology under ideal environmental conditions.  Tipped over sponges grow to resume this configuration.
--   Many/Most sponges have hollow sediment-filled Oscular Cavities or Osculum (Oscula) often with a pyrite dot in the center…
--   Branching Pattern of Extremities (arms): Normal Growth, Budding, Damage Regrowth, and Tipover Regrowth.
--   Many sponges have irregularly shaped hexagons in their anatomical structures.
--   Many sponges have a central pyrite-filled canal as a center nucleus in their oscula and incurrent pores, which often appears as a rusty dot or bullseye in the center of circular features such as  oscula, incurrent pores, and cross sections.
--   Sponges often display faint and roughly 4-Leaf Clover shaped or Irregular-Hexagon shaped patterns in growth structures, attachment points, buds, pores, openings, color changes in the sediments infilling the oscular cavity, cross-section, and in weathering patterns.
-- Tip-over and Regrowth angles and patterns occur in some specimens as evidence of damage control adaptations.
--   Some species of sponges are dimorphic with flat and discoidal horizontal forms as well as classic upright vertical forms.  Adapting to environmental conditions and changes.
--   Sponges often demonstrate preferential substrates and take special advantage of shells and tests of other organisms.
--   Many sponges are opportunistic settlers well-adapted for settling and pioneering on and in muddy bottoms.
--   Some larval sponges have both Upright and flat Discoidal growth patterns which develop according to how they land on their substrates.
--   Balance.  Sponges are adapted for Balance.  Fossil sponges retain that balance.  One can recount the life history and chronology of living and fossil sponges recorded in their morphology similarly to studying and ascertaining cross-cutting relationships.
-- “Haeckel's Tree” Branching spicule-supported system of flagellated canals.
--   Some sponges have flat discoidal attachment surfaces with which they contact their substrates.
--   Some sponges have wide but slender "Beaver Tail" wedge shaped anchors at bottom for muddy bottom benthic ecology.
--   Some sponges have conical pointed cone shaped anchors at their bottom (apex) convergent upon the "horns" of Rugosa.
--
Some sponges demonstrate "Rollerball" rotation for balance, growth, and regrowth following tipover or damage.
--   Sponges Lack the regular geometric features and textural patterns seen in corals due to the lack of a calcium carbonate skeleton as found in most corals.
--    Sponges have spicules which they can rearrange and reshape themselves with great plasticity.
--   Most Chert and Chert Nodules are formed from accumulations of recrystallized sponge spicules.  If Chert, then Sponge.
--   The "acid test" of sponges is, of course, the microscopic thin section analysis for spicules.
..........................
Research Paper Abstract (Bruner & Smosna, 2002)
Cherty sponge reefs in the Devonian Onondaga Limestone: Newly discovered gas reservoir in Pennsylvania
January 2002
Kathy Bruner
& Richard Smosna
Abstract
Recent wells drilled to the Onondaga Limestone in northwestern Pennsylvania have encountered previously unknown sponge reefs comprised of porous chert and nonporous limestone. The chert represents fossil sponges-small globular encrusting with large numbers of spicules-that underwent neomorphism from biogenic opal to microcrystalline quartz. Abundant calcitic material has been incorporated into the chert masses, presumably calcareous sediment taken into the sponges' body by the organisms themselves. In addition, thin beds of skeletal-peloidal grainstone occur within and over the reef rock. The porous chert masses range in size up to several centimeters. Most of the pore volume, and up to 18% of the total rock volume, consists of open tubes having the same shape and size as the siliceous monaxon spicules (straight cylinders, 150-800 μm long, 10-110 μm in diameter). Inside a single sponge, the tubular pores are relatively uniform in size and commonly exhibit a parallel orientation. These pores clearly represent the molds of dissolved spicules. Additional pore types in the chert include micropores, small vugs, and microfractures. Total porosity, however, has been significantly reduced by physical compaction as well as cementation by chert, calcite, collophane, and bitumen.
================================
My fossil sponges come from the surface bedrock exposures of the
Onondaga
Limestone that occur in southern Ontario Canada, under Lake Erie, and in Western New York.  They have been liberated from the bedrock by repeated cycles of Ice Age glaciation as well as 390 million years of uplift and erosion and and weathering and concentration of these
indestructible
solid chert fossils in glacial and lakeshore deposits.
PREPARATION:
Repeated soakings in hydrochloric acid followed by repeated scrubbings with detergents.  These solid chert fossils are largely indestructible and hold up to 50% HCl baths for days at a time. Many detergent scrubbings between acid baths.  A final coating of detergent (Dawn) is spread over most fossil surfaces to bring out details, to further loosen matrix particles during dormancy or in transit, and unlike paints and glues and oils, it can easily be scrubbed off with hot water (It's only Soap!)  I leave a light coating of Dawn on most of my fossils and museum specimens to bring out surface details.  Wash off and/or reapply at your pleasure.
KEYWORDS: fossils rocks minerals shells sponge fossil sponges biology geology science teaching education fossils.