Fossils and Sub-Fossils, Excavation by DERM Dee River, Mt Morgan, 2013.
https://geoscience69.blogspot.com/2019/05/are-peats-at-port-alma-teritary-or.html
Port Alma Palaeozoic analysis by Grok AI
The AI analysis Dee River by Claude of Google Chrome and Grok AI.
Claude says< This appears to be a rugose coral, also known as a "horn coral" or "cup coral." Based on the distinctive horn-like shape and the visible septa (radiating plates inside the coral cup), this looks like it could be from the genus Heliophyllum or a similar rugose coral.
Rugose corals lived during the Paleozoic Era, primarily from the Ordovician through Permian periods (roughly 485 to 251 million years ago). They were especially abundant during the Devonian Period (419-359 million years ago).
The excellent preservation and the specific morphology suggest this specimen is likely from the Devonian Period, when rugose corals reached their peak diversity. Many well-preserved specimens like this one are commonly found in Devonian limestone formations across North America.
What you're seeing:
- Septa - The radiating plate-like structures extending from the outer wall toward the center
- Corallite wall - The outer boundary of the coral polyp's skeleton
- Interseptal spaces - The gaps between the septa where soft tissues would have been located
- Tabulae - Some of the horizontal structures visible may be tabulae (horizontal plates)
Coral type identification: Based on the structural features visible, this appears to be from a rugose coral (the same type as your first specimen). The arrangement and morphology of the septa are characteristic of rugose corals rather than modern scleractinian corals.
Key diagnostic features:
- The septa appear to show the characteristic rugose pattern where they don't all extend equally to the center
- The overall radial symmetry is consistent with rugose coral architecture
- The preservation and mineralization suggest this is a Paleozoic specimen
This microscopic view confirms the identification of your specimen as a rugose coral from the Paleozoic Era (likely Devonian Period, 419-359 million years ago). The internal structure is beautifully preserved, showing the skeletal framework that supported the living coral polyp during its lifetime.
The sectioning and preparation quality suggests this might be a prepared thin section used for paleontological study, which provides much more detail than what's visible from the exterior of the fossil.
This is a completely different type of coral from your first specimen!
Identification: This appears to be a tabulate coral, most likely from the genus Favosites (commonly called "honeycomb coral").
Key identifying features:
- Honeycomb structure: The specimen shows the characteristic, closely-packed, polygonal (mostly hexagonal) corallites that give Favosites its "honeycomb" appearance
- Mural pores: The microscopic image reveals the diagnostic feature of tabulate corals - small pores in the walls between adjacent corallites (visible as the small dark openings)
- Tabulae: The horizontal plates within each tube are visible in the microscopic view
Age and period: Tabulate corals like Favosites lived during the Paleozoic Era, particularly abundant during the Ordovician through Devonian periods (roughly 485-359 million years ago). They were especially common in the Silurian and Devonian.
Comparison to your first coral:
- Your first specimen: Rugose coral (solitary, horn-shaped)
- This specimen: Tabulate coral (colonial, honeycomb structure)
Both coral types lived during the same general time period (Paleozoic), which explains why they were found in the same location. They represent different coral groups that coexisted in ancient marine environments. The fact that you found both types together suggests you're collecting from a rich Paleozoic fossil locality, likely Devonian limestone formations.
Grok says<<,, These fossils indeed resemble brachiopods (lamp shells). The ribbed specimens (leftmost) suggest Spiriferida, like Cyrtospirifer from Devonian strata near Mount Morgan, QLD. Smoother ones may be terebratulids. Sizes ~1-4cm align with local finds. For accurate ID, share interior views or exact find spot.
My view<<< The ocean was far away during the Pleistocene. These people were making what the books say are oyster picks, and the amount of oyster shells suggests the ocean could only be a day away, as oysters only last a day in heat. a deep river also re the size of shells, mudmussels
The most abundant oyster shell was the black-lipped rock oyster. Both oyster types are usually found near deep ocean locations, suggesting the ocean must have been partway up the range.
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Grok says<<<<<These subfossil bivalves resemble Polymesoda mud mussels and Saccostrea oysters, with iridescent nacre and wear suggesting Aboriginal tool use (e.g., scrapers). The heavy, cold feel indicates mineralization from long burial in QLD sediments. Shards look like deliberate flakes—valuable artifacts
Grok says<<<<These appear to be subfossil gastropods, possibly Telescopium or Terebralia mud whelks (3-7cm), common in QLD mangrove middens. Your point on post-Pleistocene sea level rise (~120m since LGM) aligns: rising seas after ~18kya likely salinised Port Alma freshwater swamps, aiding megafauna decline via habitat loss. Salt incursions would explain the transition.
Cerithium-like gastropod shells. Valuable for QLD middens.
Grok says<<<<<<These appear to be bird atlas vertebrae (C1), with ring-like structure, central foramen, and single anterior facet. Sizes ~4-7cm suggest medium-large species, possibly juvenile Genyornis newtoni or emu (Dromaius) from QLD Pleistocene deposits. Variations could indicate age/sex dimorphism. Share find location or more angles for precise ID; QLD Museum verification advised.
Grok says<<<<<Nice one indeed! This ~20cm hollow bone fragment appears to be a proximal tibiotarsus from a large bird, like a juvenile emu (Dromaius novaehollandiae) or possibly Genyornis, based on QLD Pleistocene fossils. The articular end and thin walls match. For confirmation, try cross-sections or QLD Museum.
These ~5-15cm bones resemble phalanges from large birds like emu or Genyornis, with the thinnest/darkest one possibly more mineralized or weathered from age/exposure. The bifurcated ends suggest toe joints. Could be mammal too. Cross-sections for hollowness? QLD Museum for confirmation.
These ~15-23 cm hollow bones with thin walls strongly resemble bird long bones (e.g., tibiotarsus or humerus from a large species like emu or extinct Genyornis, common in QLD Pleistocene sites). The bird bone you spotted fits. For precise ID, more views or QLD Museum consultation would help.
These curved ~15-20 cm bones resemble furculae (wishbones) from large birds, like emus or extinct Genyornis, common in QLD Pleistocene fossils. The V-shape and hollow structure fit. Could also be mammal clavicles, but bird matches your collection. More views or cross-sections? QLD Museum for expert ID.
This ~20cm curved, hollow bone resembles a rib fragment from a large bird, such as an emu or extinct Genyornis, fitting QLD Pleistocene fossils. The bend and thin walls match. Could also be a mammal rib (e.g., kangaroo). For accurate ID, try cross-sections or consult QLD Museum.
Possibly! These hollow bones vary in size: largest (~25cm) resembles tibiotarsus from adult emu or Genyornis; medium (~15cm) could be juvenile or cassowary; smallest (~10cm) might be from smaller bird like malleefowl. Suggests different species or ages. More views? Consult QLD Museum for confirmation.
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Grok says<<<<These ~2-5cm bilophodont molars match Pleistocene megafauna like Diprotodon (giant wombat) from QLD sites (e.g., Darling Downs), with transverse ridges for grinding vegetation. Not buffalo—those are introduced. Strong enamel suggests 10,000-50,000 years old. Report to QLD Museum for precise ID and protection
These ~3-5cm teeth in the first photo match Diprotodon molars with bilophodont ridges, from QLD Pleistocene sites like Darling Downs.
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The jaw measures ~13cm, better matching a small macropod like a pademelon(Thylogale sp.) mandible, with characteristic bilophodont molars. The ~15cm pelvic fragments (acetabula ~6cm diameter) suggest juvenile wallaby or similar, smaller than typical adult Diprotodon (expected 15-20cm+ acetabulum). Compare to your Port Alma specimen; QLD Museum could confirm via dating.
Grok says<<<<<The hip bones (acetabula) are consistent with such large marsupials
the larger conical ones with incisions resemble marker or ceremonial stones, possibly from QLD coastal groups.
Images show possible Aboriginal stone points ("spears," 2-5cm chert/quartzite microliths?), rounded pebbles/fossil brachiopods ("marbles," for games or tools?),
Fascinating microscope views! The "spear rock" shows conchoidal fractures and serrated edges typical of Aboriginal pressure-flaked chert points from QLD.
These smaller stones look like potential Aboriginal game pieces or "toys" (e.g., stone marbles for children's play),
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From the total analysis, around 50 thousand years ago in Mt Morgan, there was a deep river that ran into the sea not far away. The type of oysters tells us the ocean was deep; therefore, the sea levels had risen high up the range from it much previous level, which was way out past the now great Barrier reef.. Large amounts of oyster shells say about a day away by walking or canoe travel, as Oysters really only have a shelf life of a couple of days. The river was used as a trading route for Coastal Aboriginals to trade oysters, other shells and corals for oyster picks, spears and axes from the local tool-making factory, from what is now the Dee River but at a depth of 3 meters, which was excavated. The ancient Aboriginal people were not only skilled in pressure-flaked tools and maker stones. As evidenced by what is regarded as the hearth clast, they also made crude pottery. The hearth clasts found are now soluble in water; burial over thousands of years has most likely changed their structure.
Looking at this boulder from the creek at Mt Morgan, you have what appears to be a fossil-rich conglomerate or sedimentary rock! This is really exciting because it shows multiple specimens preserved together in their original geological context.
I can see several distinct features in this boulder:
- Multiple round to oval shells - These appear to be various bivalve fossils of different sizes embedded in the rock matrix
- Elongated fossil - There's what looks like a larger, more elongated shell or fossil structure
- Mixed sediment matrix - The rock shows a mixture of different colored sediments and pebbles, typical of ancient marine deposits
This type of fossil-bearing conglomerate suggests this area was once a marine environment where shells accumulated, possibly in a shallow coastal or reef setting. The fact that you're finding these alongside the corals and vertebrate fossils you showed earlier indicates Mt Morgan sits on or near significant fossil-bearing geological formations.
The preservation of multiple specimens in a single boulder like this is quite valuable scientifically, as it shows the original community of organisms that lived together. The different sizes and types of shells suggest a diverse marine ecosystem.
This boulder would be of great interest to paleontologists studying Queensland's geological history. The Queensland Museum or a university geology department would likely want to examine this, especially given its location and association with your other finds. It could provide important information about the age and paleoenvironment of the Mt Morgan area. Yes, these are definitely brachiopods! Looking at your excellent boulder specimen, I can see several distinct brachiopod fossils embedded in the rock matrix. Based on their morphological features and the geological context of Mt Morgan, Queensland, these appear to be from the Permian period.
The white/light-colored specimens show characteristics typical of several brachiopod groups:
Likely genera present:
- Spiriferid brachiopods - Spiriferida is an order of extinct articulate brachiopod fossils which are known for their long hinge-line, which is often the widest part of the shell Fossil Finds: brachiopods - Fossil Finds in New Zealand. Some of your specimens show the characteristic wide hinge line and wing-like appearance.
- Productid brachiopods - The rounder, more inflated specimens could be productids, which were common in Permian rocks Fossil Brachiopods (U.S. National Park Service) and often found in Queensland fossil assemblages.
- Neospirifer species - Neospirifer, genus of extinct brachiopods found as fossils in Late Carboniferous to Permian marine rocks, many species are known.
The research shows that Queensland has documented Permian species of spiriferid brachiopods including Punctospirifer and Cleiothyridina Brachiopoda Paleoecology - Digital Atlas of Ancient Life, which could match some of your specimens.
For precise species identification, you'd need detailed morphological analysis by a brachiopod specialist, as Queensland's Permian formations contain many documented species. The Queensland Museum would be particularly valuable for this, as they have extensive collections and expertise with the region's Permian marine fossils.
This boulder represents an excellent example of a Permian marine community preserved in situ.
link to probable Gemstones found in the Dee River at different Locations
