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Facies characterisation of a shallow-water deltaic succession: the Upper Jurassic Wagad Sandstone Formation of Kachchh, western India

Joseph J. K., Patel S. J.

Geologos

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2018

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Vol. 24, No. 2

137--150

EN

Ancient deltaic facies are difficult to differentiate from tidally influenced shallow-marine facies. The Wagad Sandstone Formation of the Wagad Highland (eastern Kachchh Basin) is typified by offshore and deltaic facies with sedimentary characteristics that represent different conditions of hydrodynamics and related depositional processes. The study area, the Adhoi Anticline, constitutes a ~154-m-thick, shale-dominated sequence with progressive upward intercalations of bioturbated micritic sandstone and quartz arenite. Two thick Astarte beds (sandy allochemic limestone), with an erosional base and gravel blanketing, illustrate tidal amplification and high-energy stochastic events such as storms. Sedimentological characteristics document three depositional facies: an offshore, shale-dominated sequence prograding to proximal prodeltaic micritic sandstone and quartz arenite with sandy allochemic limestones, further prograding to mouth bars and abandoned channel deposits. The Wagad Sandstone Formation displays depositional environmental conditions that are dissimilar from those of coeval deposits in Kachchh sub-basins as well as on regional and global scales. This is attributed to a reactivation of the Kachchh Mainland and South Wagad faults which resulted in detachment and uplift of the Wagad block which then experienced prograding deltaic conditions.

2

Selected Oxfordian brachiopods from Zalas (Cracow Upland, Poland)

Radwańska U.

Acta Geologica Polonica

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2017

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Vol. 67, no. 3

433--440

EN

Small brachiopods of the families Craniidae Menke, 1828 and Thecidellinidae Elliott, 1958 were selected from the Oxfordian sequence which lies transgressively upon a Variscan rhyodacite laccolite exposed at Zalas in the Cracow Upland, southern Poland, a site which is well-known due to various kinds of ubiquitous fossils. The craniids include three species: Craniscus bipartitus (Münster in Goldfuss, 1837), Craniscus tripartitus (Münster in Goldfuss, 1837) and Craniscus antiquior (Jelly, 1843), and the thecidellinids – two species: Rioultina zalasensis sp. nov. and Rioultina wapiennensis Krawczyński, 2008. The species described herein indicate tropical or subtropical waters, and a moderately (?) deep character of the sea basin at Zalas.

3

A rare comatulid crinoid, Semiometra petitclerci (CAILLET, 1923), from the Upper Oxfordian of Poland

Radwańska U.

Acta Geologica Polonica

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2007

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Vol. 57, no. 2

161-167

EN

A small faunule of feather stars or comatulids (free-living crinoids of the order Comatulida A.H. CLARK, 1908) is recorded from Upper Oxfordian strata (Bielawy/Wapienno sequence) in the Couiavia region, north-western Central Poland. It represents a single, very small-sized species, Semiometra petitclerci (CAILLET, 1923), hitherto an extreme rarity in the Jurassic sequences of France and Germany. The present record extends the geographic distribution of the species in Europe, to evidence a wider range of the genus Semiometra GISLEN, 1924, prior to its fairly common occurrence and higher diversity during the Late Cretaceous.

4

Systemy piętrowych nor krewetek-alfeuszy i ich znaczenie środowiskowe w oksfordzie i kimerydzie Gór Świętokrzyskich

Radwańska U., Radwański A.

Volumina Jurassica

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2004

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Vol. 2, no. 1

113-130

EN

To the activity of alpheid shrimps genus Alpheus Weber, 1795) ascribed are the tiered burrows of a gridlike appearance from Lower Kimmeridgian oolitic shoals and Middle Oxfordian nearshore micritic limestones of the Holy Cross Mountains, Central Poland. The burrow networks are confined to beds of the soft or hard bottom type, the upper parts of which are more or less deeply truncated, to indicate erosional events of storm agitation. At low stand, the open burrows served as traps for solutions derived from the nearby hypersaline lagoons of the sabkha type, to cause precipitation either of dolomite, or of silica gel. At high stand, the open burrows, exemplified by the Małogoszcz section (Lower Kimmeridgian), became taphonomic traps and/or crevice habitats for diverse biota, the echinoderms in particular, to form their graveyards (EchinodermenlagerstŹtten). In these, represented are echinoids (tests, some spine-coated, all either empty, or sediment-filled; broken tests and their fragments, spines) stalkless crinoids (cusps, centrodorsals, radials, brachials, cirrals), stalked crinoids (columnals, pluricolumnals), starfish (marginalia, ambulacral plates), and ophiuroids (vertebrae, arm plates). Eco-taphonomic pathways for particular echinoderms (21 taxa taxonomically recognised) are interpreted since their death to burial in open burrows. Spine-coated echinoids were entrapped alive, others were swept into during successive storms which acted as a lethal agent. The storms, catastrophic for echinoderm communities, have prevailed through a longer timespan, when the alpheid-burrowed shoal evolved from the soft bottom to the hard ground colonized by a successive echinoderm community dominated by stalked crinoids.

5

Jeżowce oksfordu Bałtowa

Radwańska U.

Volumina Jurassica

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2004

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Vol. 2, no. 1

131-140

EN

The autecology of echinoids from the Middle Oxfordian coraliferous limestones of Bałtów (NW margin of the Holy Cross Mountains, Central Poland) is discussed, as aparent from the morphology of tests, ambulacral pores for tube feet, and spines. Inferred is mode of life, locomotion, and feeding, as well as the diet of the taxonomically recognised three species: Paracidaris florigemma (Phillips, 1829) – spines only, Glypticus hieroglyphicus (Goldfuss, 1826), and Hemicidaris merryaca Cotteau, 1850, the latter reported for the first time in Poland. The phenotypic convergence is indicated of such species as: P. florigemma and extant Eucidaris tribuloides Desmoulins, 1835, of Florida and the Caribbean, as well as G. hieroglyphicus and extant Colobocentrotus atratus (Linnaeus, 1758) of the Indo-Pacific. Environmental conditions, under which the Bałtów echinoids lived, are concluded as extremely shallow marine (shallow subtidal up to low-intertidal), connected with the Bałtów coral patch reef nearby.

6

Aberrantne rozgwiazdy z rodzaju Sphaeraster Quenstedt, 1875, w profilu oksfordu Wapienno/Bielawy na Kujawach

Radwańska U.

Volumina Jurassica

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2003

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Vol. 1, no. 1

63-70

7

Oxfordian and Kimmeridgian of the northeastern margin of the Holy Cross Mountains, Central Poland

Gutowski J.

Kwartalnik Geologiczny

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1998

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Vol. 42, nr 1

59-72

EN

In Late Jurassic the area of Central Poland was a part of the northern Tethyan shelf which developed in the margins of the East European Craton. The present day NE margin of the Holy Cross Mountains was situated in a proximal part of thhis shelf. The Oxfordian sedimentationbegan with open shelf, sponge-algal mudstones of the mariae, cordatum, and plicatilis Zones. During the latest transversarium and bifurcatus Chrons, shallow water biogenic and oncolitic facies developed. They were, in turn, replaced during the Late Oxfordian and the Early Kimmeridigian by oolitic-bioclastic grainstones and laminites. During the divisum Chron and the Late Kimmeridgian oyster shellbeds and clays were deposited. Within the studied sequence thirteen lithostratigraphic units are esablished and described. The collected ammonite fauna document the following ammonite zones: mariaem cordatum, plicatilis, transversarium, bifurcatus, planula, hypselocyclum and divisum.

PL

Opracowanie przedstawia syntezę lito- i biostratygrafii utworów górnojurajskich północno-wschodniego obrzeżenia Gór Świętokrzyskich odsłaniających się między Dobrutem i Wierzbicą, w okolicach Iłży, w dolinie Kamiennej od Przepaści, przez Bałtów po Skarbkę oraz nad Wisłą w Zawichoście i Rachowie. Na podstawie 76 profili z odsłonięć i otworów wiertniczych wyróżniono 13 nieformalnych jednostek stratygraficznych. Obejmują one zarówno osady dolnego i niższej części środkowego oksfordu wykształcone w facji gąbkowej i mikrytowej otwartego szelfu, jak i utwory płytkowodnej facji platformy węglanowej, tworzone od przełomu poziomów transversarium i bifurcatus, a wykształcone początkowo jako wapienie biogeniczne z koralami, a następnie wapienie onkolitowe, oolitowe oraz laminaty i wreszcie (od poziomu divisum) - muszlowce ostrygowe i margle. Na podstawie kolekcji amonitów obejmującej 94 okazy udokumentowano następujące poziomy amonitowe: mariae, cordatum, plicatilis, transversarium, bifurcatus, planula, hypsalocyclum oraz divisum. W wyniku neokimeryjskiego ścięcia erozyjnego utwory neokomu lub albu kontaktują z różnymi ogniwami górnej jury. Najgłębiej neokimeryjska erozja sięgnęła w rejonie Ożarowa, gdzie piaskowce albu kontaktują bezpośrednio z muszlowcami ostrygowymi poziomu divisum.

8

Profil wiercenia Kcynia IG IV i jego znaczenie dla stratygrafii i paleogeografii oksfordu i dolnego kimerydu

Matyja B. A., Wierzbowski A.

Biuletyn Państwowego Instytutu Geologicznego

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1998

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nr 382

35-74

PL

Opracowanie paleontologiczne kolekcji amonitów oksfordu i dolnego kimerydu z wiercenia Kcynia IG IV z północnej Polski pozwoliło na zrewidowanie biostratygrafii występujących tu utworów i wydzielenie w całym profilu submedyterańskich poziomów i podpoziomów amonitowych. Oprócz obecnych w całym profilu amonitów submedyterańskich, ilościowe zestawienie przedstawicieli prowincji borealnej i subborealnej pozwoliło wykazać, że najsilniejsze wpływy tych prowincji rejestrują się w dolnej części poziomu Bimammatum i najwyższej części poziomu Hypselocyclum. Występowanie amonitów charakterystycznych dla różnych prowincji biogeograficznych w tych samych przedziałach profilu pozwoliło na wyróżnienie nowych powiązań korelacyjnych pomiędzy różnymi podziałami biostratygraficznymi: (1) dolna granica subborealnego poziomu Baylei, równoważna w podziale subborealnym dolnej granicy kimerydu, przebiega w obrębie wyższej części submedyterańskiego poziomu Bimammatum, (2) dolna granica subborealnego poziomu Mutabilis (sensu Birkelund i in., 1983) przebiega w obrębie najwyższej części submedyterańskiego poziomu Hypselocyclum. Analiza paleoekologiczna rozprzestrzenienia poszczególnych rodzin amonitów submedyterańskich w Polsce wskazuje, że w najwcześniejszym kimerydzie istniało bezpośrednie połączenie umożliwiające swobodne przemieszczanie amonitów pomiędzy północną Polska, a obszarami Jury Frankońskiej i Jury Szwabskiej poprzez obszary obecnie pozbawione osadów górnojurajskich.

EN

Palaeontological study of the ammonite collection of the Oxfordian and Lower Kimmeridgian in the Kcynia IG IV borehole in northern Poland has resulted in biostratigraphical revision of the succession and allowed the recognition of the Submediterranean Zones and Subzones. Although Submediterranean ammonites overdominate in the succession, Subboreal and Boreal ammonites increase proportionally in the lower Bimammatum Zone and the uppermost Hypselocyclum Zone reflecting significant ammonite invasions from the north. The co-occurrence of the ammonites indicative of different bioprovinces in the same intervals of the studied succession permits closer correlation of the zonal schemes. The new results of the correlation are as follows: (1) the lower boundary of the Baylei Zone of the Subboreal zonal scheme corresponding therein to the lower boundary of the Kimmeridgian lies within the upper part of the Submediterranean Bimammatum Zone, (2) the lower boundary of the Subboreal Mutabilis Zone (sensu Birkelund et al., 1983) lies within the uppermost part of the Submediterranean Hypselocyclum Zone. Palaeoecological analysis of the distribution of ammonites representing the particular Submediterranean families in Poland has shown that during the earliest Kimmeridgian there existed a direct marine connection between northern Poland and the Franconian and Swabian Albs enabling free migration of ammonites through the areas presently devoid of Upper Jurassic deposits.