Near Shore -Shallow Marine (Ophiomorpha and Margaritichnus) Trace Fossils from Fatehgarh Formation of Barmer Basin, Western Rajasthan, India

2016 ◽  
Vol 06 (01) ◽  
Author(s):  
Parihar VS ◽  
Nama SL
Keyword(s):  
Trace Fossils ◽  
Shallow Marine ◽  
Barmer Basin ◽  
Near Shore

Trace Fossils in Quaternary, Bahamian-Style Carbonate Environments: The Modern to Fossil Transition

1992 ◽  
Vol 5 ◽  
pp. 105-120 ◽  
Author(s):  
H. Allen Curran
Keyword(s):  
Fossil Record ◽  
Trace Fossils ◽  
Subtidal Zone ◽  
Carbonate Sediments ◽  
Shallow Marine ◽  
Shallow Subtidal ◽  
Dominant Process ◽  
Burrowing Activity

Tracemaking organisms are common and diverse components of the fauna and flora of tropical, shallow-marine and coastal carbonate environments. In the shallow subtidal zone, the burrowing activity of callianassid shrimp commonly is the dominant process in the modification of original depositional fabrics (Tudhope and Scoffin, 1984; Tedesco and Wanless, 1991). Both borers and burrowers have great potential to leave their mark in tropical carbonate sediments and rocks and to become part of the fossil record.

The Fish River Subgroup in Namibia: stratigraphy, depositional environments and the Proterozoic–Cambrian boundary problem revisited

2005 ◽  
Vol 142 (5) ◽  
pp. 465-498 ◽  
Author(s):  
G. GEYER
Keyword(s):  
Trace Fossils ◽  
Global Scale ◽  
Depositional Environments ◽  
Trace Fossil ◽  
Braided River ◽  
Shallow Marine ◽  
Sequence Stratigraphic ◽  
Marine Habitats ◽  
Short Period ◽  
Distinct Sequence

The Fish River Subgroup of the Nama Group, southern Namibia, is restudied in terms of lithostratigraphy and depositional environment. The study is based on partly fine-scaled sections, particularly of the Nababis and Gross Aub Formation. The results are generally in accordance with earlier studies. However, braided river deposits appear to be less widely distributed in the studied area, and a considerable part of the formations of the middle and upper subgroup apparently were deposited under shallowest marine conditions including upper shore-face. Evidence comes partly from sedimentary features and facies distribution, and partly from trace fossils, particularly Skolithos and the characteristic Trichophycus pedum. Environmental conditions represented by layers with T. pedum suggest that the producer favoured shallow marine habitats and transgressive regimes. The successions represent two deepening-upward sequences, both starting as fluvial (braided river) systems and ending as shallow marine tidally dominated environments. The first sequence includes the traditional Stockdale, Breckhorn and lower Nababis formations (Zamnarib Member). The second sequence includes the upper Nababis (Haribes Member) and Gross Aub formations. As a result, the Nababis and Gross Aub formations require emendation: a new formation including the Haribes and Rosenhof and possibly also the Deurstamp members. In addition, four distinct sequence stratigraphic units are deter-minable for the Fish River Subgroup in the southern part of the basin. The Proterozoic–Cambrian transition in southern Namibia is most probably located as low as the middle Schwarzrand Subgroup. The environmentally controlled occurrence of Trichophycus pedum undermines the local stratigraphic significance of this trace fossil which is eponymous with the lowest Cambrian and Phanerozoic trace fossil assemblage on a global scale. However, occurrences of such trace fossils have to be regarded as positive evidence for Phanerozoic age regardless of co-occurring body fossils. Other suggestions strongly dispute the concept of the formal Proterozoic–Cambrian and Precambrian–Phanerozoic boundary. Carbon isotope excursions and radiometric datings for the Nama Group do not help to calibrate precisely the temporal extent of the Fish River Subgroup. Fossil content, sequence stratigraphy and inferred depositional developments suggest that this subgroup represents only a short period of late orogenic molasse sedimentation during the early sub-trilobitic Early Cambrian.

scholarly journals Lower Cambrian trace fossils from the Buen Formation of central North Greenland: preliminary observations

1990 ◽  
Vol 147 ◽  
pp. 44-62
Author(s):  
I.D Bryant ◽  
R.K Pickerill
Keyword(s):  
Lower Cambrian ◽  
Trace Fossils ◽  
Shallow Marine ◽  
Basal Portion ◽  
North Greenland

The trace fossils Cruziana cf. C. stromnessi (Trewin, 1976), Curvolithus Fritsch, 1908, Hormosiroidea Schaffer, 1928, Monomorphichnus cf. M. bilinearis Crimes, 1970, Monomorphichnus lineatus Crimes et al., 1977, cf. Palaeobullia Gotzinger & Becker, 1932, Palaeophycus tubularis Hall, 1847, Phycodes pedum Seilacher, 1955, Psammichnites Torell, 1870, Rusophycus Hall, 1852, Skolithos Haldeman, 1840 and cf. Zoophycos Massalongo, 1855 are recorded and briefly described from the Lower Cambrian Buen Formation, central North Greenland. Interbedded sandstones, siltstones and shales of the Buen Formation were deposited in a tide and storm-dominated shallow marine shelf environment. Ichnofaunal diversity is low in monolithologic cross-bedded sandstones, which characterise the basal portion of the sequence, and considerably higher in heterolithologic sandstones, siltstones and shales, which occur higher in the sequence.

scholarly journals Sedimentology and ichnology of the mid-Cretaceous succession of Ouled Nail Mounts (Eastern Saharan Atlas, Algeria)

2021 ◽  
Vol 74 (3) ◽  
pp. 209-223
Author(s):  
Mohammed Nadir Naimi ◽  
◽  
Amine Cherif ◽  
Keyword(s):  
Trace Fossils ◽  
Decapod Crustaceans ◽  
Shallow Marine ◽  
Marine Deposits ◽  
Northern Algeria ◽  
Continental Intercalaire ◽  
Lowermost Part ◽  
Maximum Flooding Surface ◽  
Glossifungites Ichnofacies

Shallow marine deposits characterize the upper Albian – lower Cenomanian deposits of Northern Algeria. In Djebel Azzeddine (Ouled Nail Mounts), the corresponding sediments have been subdivided into three distinctive units A to C. The first discovered ammonite fauna from the Bou Saada area allowed the attribution of a part of the mid-Cretaceous post-Continental Intercalaire deposits to the upper Albian. The ammonite-bearing level indicates a maximum flooding surface and could be correlated with similar levels from Northern Algeria. The studied succession is characterized by a low ichnodiversity containing eight ichnotaxa with abundant Thalassinoides, common Skolithos, and rare Gyrolithes, Oichnus, Planolites and cf. Tisoa. This ichnoassemblage is dominated by domichnion, fodinichnion and praedichnion trace fossils, and is attributed to the Skolithos and Glossifungites ichnofacies. These traces are produced mainly by decapod crustaceans, polychaetes and naticid gastropods. The sedimentological and ichnological data suggest shoreface to backshore environments with mixed tide/storm energy, and long subaerial exposures indicated by Lofer cyclothems in the lowermost part and dinosaur footprints in the upper part of the section.

scholarly journals Exploring Ichnofacies Distribution in Ancient Seaways: The Late Miocene Rifian Corridor as a Natural Laboratory

2020 ◽  
Author(s):  
Wouter de Weger ◽  
Francisco Rodríguez-Tovar ◽  
Olmo Miguez-Salas
Keyword(s):  
Ocean Circulation ◽  
Late Miocene ◽  
Trace Fossils ◽  
Shallow Marine ◽  
Climatic Variations ◽  
Fine Grain ◽  
Major Controlling Factor ◽  
Palaeoenvironmental Conditions ◽  
Natural Laboratory ◽  
Ophiomorpha Rudis

Abstract Oceanic gateways have modulated ocean circulation and have influenced climatic variations throughout the Earth´s history. During the Late Miocene (7.8 - 7.35 Ma), the Atlantic Ocean and the Mediterranean Sea were connected through the Rifian Corridor (Morocco). This gateway is one of the few examples of deep ancient seaways with a semi-continuous sedimentary record. Deposits comprise turbidites intercalated between deep-sea fine grain sediments (i.e., hemipelagites and drift deposits), channelized sandstone contourite facies, and shallow marine sandstones. Herein an ichnological analysis was conducted in these upper Miocene sediments to improve characterisation of palaeoenvironmental conditions. In addition, ichnofacies were analysed to elucidate how bottom currents control ichnofacies distribution and can modified their attributes. Turbidite deposits are typified by vertical trace fossils (i.e., Ophiomorpha), conforming the Ophiomorpha rudis ichnosubfacies. Contouritic sandstones exhibit high density and low diverse trace fossil assemblage, with predominant Macaronichnus and Scolicia, resembling a proximal expression of Cruziana ichnofacies. Shallow marine environments are dominated by vertical trace fossils (e.g., Conichnus, Ophiomorpha and Skolithos), allowing an assignation to Skolithos ichnofacies. This study reveals energy to be a major controlling factor determining ichnofacies attributes and distribution in ancient deep seaways. Within these seaways, highly energetic conditions typical of shallower settings are present in deeper environments (i.e., slope), contributing to ichnodiversity impoverishment in ichnofacies.

scholarly journals Early complex tiering pattern: Upper Ordovician, Barrandian area, the Czech Republic

2021 ◽  
Vol 77 (1) ◽  
pp. 17-35
Author(s):  
Pavel Bokr ◽  
Radek Mikuláš ◽  
Petr Budil ◽  
Petr Kraft
Keyword(s):  
Czech Republic ◽  
Trace Fossils ◽  
Preferred Orientation ◽  
Upper Ordovician ◽  
The Czech Republic ◽  
Shallow Marine ◽  
Fine Grained ◽  
Bedding Planes ◽  
Barrandian Area

Upper Ordovician shallow marine fine-grained sandstones and siltstones exposed in the Loděnice – vinice locality yielded a distinct and well-preserved tiering pattern of trace fossils. The two uppermost tiers are composed mainly of Bifungites and Nereites. Deeper in the sediment, tiers dominated by Thalassinoides, Zoophycos and Teichichnus occur. Most of the succession is completely bioturbated; however, several storm layers enabled study of a well-preserved frozen tiering pattern. Large portions of the bedding planes (ichnologic snapshots) showed a considerable patchiness of intensive surface bioturbation and a preferred orientation of Bifungites. The identified tiering pattern is one of the earliest examples of a well-documented complex tiering of burrows documented in detail.

The Early Ordovician Middle Shale Member (Am3) of the Amdeh Formation and further evidence of conodont faunas from the Sultanate of Oman

2018 ◽  
Vol 156 (08) ◽  
pp. 1357-1374 ◽  
Author(s):  
AP Heward ◽  
CG Miller ◽  
GA Booth
Keyword(s):  
Gamma Ray ◽  
Trace Fossils ◽  
Heavy Minerals ◽  
Sultanate Of Oman ◽  
Shallow Marine ◽  
Middle Ordovician ◽  
Early Ordovician ◽  
Coastal Deposits ◽  
Conodont Fauna ◽  
Gamma Ray Log

AbstractThe Middle Shale Member of the Amdeh Formation is interpreted to be of Early Ordovician age based on its trace fossils, stratigraphic context and a newly discovered fauna of conodonts. The member abruptly overlies the Lower Quartzite Member, which may be Early Cambrian, and passes gradationally-upward into the Upper Quartzite Member, which is probably Early–Middle Ordovician. The 542.5 m thick Middle Shale Member can be divided into two parts: a shaly lower part, and a sandy upper part that contains an influx of heavy minerals. Bioturbation by marine trace fossils is one of the most obvious characteristics of the member. The shales and sandstones are interpreted to be of Cruziana and Skolithos ichnofacies and represent shallow-marine shelf, shoreface, beach and coastal deposits. Sparse shelly fossils occur in the sandy upper part, principally bivalves, inarticulate brachiopods, ostracods and conodonts. The small assemblage of conodonts includes elements interpreted to be Tremadocian (Tetraprioniodus, Drepanoistodus, Drepanodus, Scolopodus, ?Tropodus, Semiacontiodus and Teridontus), and others which may be Floian or ancestral forms of Floian taxa (Balognathidae gen. et sp. indet. A & B and aff. Erraticodon). No acritarchs have been recovered, probably due to high temperatures experienced during burial to >6 km. It is likely that the Middle Shale Member is the seaward equivalent of the Mabrouk and Barakat formations, and an outcrop gamma-ray log supports such a correlation. The trace fossils, sedimentology, conodont fauna and the general lack of macrofossils are in keeping with the regional Tremadocian–Floian of the Arabian margin of Gondwana.

Sign in / Sign up

Export Citation Format

Share Document