scholarly journals GeoArabia’s Infracambrian Debate: Cryogenian versus Ediacaran Models

GeoArabia ◽  
2010 ◽  
Vol 15 (2) ◽  
pp. 209-244 ◽  
Author(s):  
Moujahed I. Al-Husseini
Keyword(s):  
Middle Eastern ◽  
Volcanic Rocks ◽  
Age Dating ◽  
Petroleum Exploration ◽  
Time Interval ◽  
Zircon Geochronology ◽  
Petroleum Systems ◽  
Younger Age ◽  
Geologic Time Scale ◽  
Ca 50

ABSTRACT The Middle Eastern Infracambrian Debate offers specific choices between profoundly different tectono-stratigraphic models that have important scientific and petroleum exploration implications worldwide. A crucial first step in the Debate is choosing between the interpretations of zircon geochronology (Cryogenian Model) or regional chrono-stratigraphy based on much younger age-dating by alternative radiometric techniques (e.g. K-Ar, Rb-Sr, Ar/Ar; Ediacaran Model). The interpretation of zircon geochronology implies Oman’s oldest diamictites of the Abu Mahara Group represent the Sturtian (ca. 720–700 Ma) and Miranoan (ca. 663–636 Ma) glaciations of the Cryogenian Period (850–630 Ma) separated by the ca. 50 My Fiq-Ghubrah Hiatus. The Cryogenian Model implies three phases of rifting in the same regions between ca. 723–530 Ma, and another younger but disputed ca. 30–40 My Shuram-Khufai Hiatus occurring in a tectonically quiescent platform setting (post-glacial Nafun Group’s fine clastics and carbonates). This combined essay and book review of Global Neoproterozoic Petroleum Systems disputes the interpretation of zircon geochronology to establish absolute time for Oman’s oldest rocks. It argues for the single-rift-without-hiatus Ediacaran Model based on ages of basement and volcanic rocks using alternative radiometric techniques in Jordan, Oman and Saudi Arabia. Oman’s Hadash Formation and coeval Mirbat Cap Carbonate are believed to provide an important correlative marker that recorded the start of the great sea-level rise of the Nafun Transgression at ca. 572 Ma, not 636 Ma. The Transgression was due to the melt-out of the late Ediacaran Varanginian Glaciation (represented in Oman by the diamictites of the Ayn, combined Fiq-Ghubrah and subsurface Ghadir Manqil formations, all of the Abu Mahara Group, deposited between ca. 585–572 Ma), not the Sturtian and Miranoan glaciations. The deep-marine organic-rich shales and siliciclastics of Oman’s Masirah Bay Formation (coeval Arkahawl Formation of Mirbat Group) are syn-rift and reflect the Nafun Transgression spilling beyond the rift basins and their surrounding lowlands. As proposed in the Middle East Geologic Time Scale 2010 and GeoArabia’s Infracambrian Debate, the time interval ca. 585–530 Ma can best be cast in terms of transgressive-regressive chrono-sequences in a regional tectono-stratigraphic extensional framework.

The times they are a-changin': Australian biozones, petroleum basins, and the international geologic time scale (GTS) 2012

2014 ◽  
Vol 54 (2) ◽  
pp. 473
Author(s):  
Tegan Smith ◽  
John Laurie ◽  
Lisa Hall ◽  
Robert Nicoll ◽  
Andrew Kelman ◽  
...  
Keyword(s):  
Time Scale ◽  
Age Dating ◽  
Burial History ◽  
Geologic Time ◽  
Petroleum Systems ◽  
Geologic Time Scale ◽  
History Of ◽  
And Migration ◽  
The Times ◽  
Hydrocarbon Expulsion

The international Geologic Time Scale (GTS) continually evolves due to refinements in age dating and the addition of more defined stages. The GTS 2012 has replaced GTS 2004 as the global standard timescale, resulting in changes to the age and duration of most chronological stages. These revisions have implications for interpreted ages and durations of sedimentary rocks in Australian basins, with ramifications for petroleum systems modelling. Accurate stratigraphic ages are required to reliably model the burial history of a basin, hence kerogen maturation and hydrocarbon expulsion and migration. When the resolution of the time scale is increased, models that utilise updated ages will better reflect the true basin history. The international GTS is largely built around northern hemisphere datasets. At APPEA 2009, Laurie et al. announced a program to tie Australian biozones to GTS 2004. Now, with the implementation of GTS 2012, these ties are being updated and refined, requiring a comprehensive review of the correlations between Australian and International biozonation schemes. The use of Geoscience Australia’s Timescales Database and a customised ‘Australian Datapack’ for the visualisation software package TimeScale Creator has greatly facilitated the transition from GTS 2004 to GTS 2012, as anticipated in the design of the program in 2009. Geoscience Australia’s basin biozonation and stratigraphy charts (e.g. Northern Carnarvon and Browse basins) are being reproduced to reflect the GTS 2012 and modified stratigraphic ages. Additionally, new charts are being added to the series, including a set of onshore basin charts, such as the Georgina and Canning basins.

scholarly journals Rhenium–osmium (Re–Os) geochronology of crude oil from lacustrine source rocks of the Hailar Basin, NE China

2020 ◽  
Author(s):  
Qi-An Meng ◽  
Xue Wang ◽  
Qiu-Li Huo ◽  
Zhong-Liang Dong ◽  
Zhen Li ◽  
...  
Keyword(s):  
Crude Oil ◽  
Source Rocks ◽  
Radiometric Dating ◽  
Age Dating ◽  
Hydrocarbon Generation ◽  
Ne China ◽  
Petroleum Systems ◽  
Younger Age ◽  
Hailar Basin ◽  
Age Trends

Abstract Re–Os radiometric dating of crude oil can be used to constrain the timing of hydrocarbon generation, migration or charge. This approach has been successfully applied to marine petroleum systems; however, this study reports on its application to lacustrine-sourced natural crude oils. Oil samples from multiple wells producing from the Cretaceous Nantun Formation in the Wuerxun-Beier depression of the Hailar Basin in NE China were analysed. Subsets of the Re–Os data are compatible with a Cretaceous hydrocarbon generation event (131.1 ± 8.4 Ma) occurring within 10 Myr of deposition of the Nantun Formation source rocks. In addition, two younger age trends of 54 ± 12 Ma and 1.28 ± 0.69 Ma can be regressed from the Re–Os data, which may reflect the timing of subsequent hydrocarbon generation events. The Re–Os geochronometer, when combined with complementary age dating techniques, can provide direct temporal constraints on the evolution of petroleum system in a terrestrial basin.

About this title - Application of Analytical Techniques to Petroleum Systems

10.1144/sp484 ◽  
2020 ◽  
Vol 484 (1) ◽  
pp. NP-NP
Author(s):  
Patrick J. Dowey ◽  
Mark Osborne ◽  
Herbert Volk
Keyword(s):  
Oil And Gas ◽  
Organic Geochemistry ◽  
Analytical Techniques ◽  
Petroleum Exploration ◽  
Electricity Production ◽  
Sediment Provenance ◽  
Chemical Production ◽  
Petroleum Systems ◽  
Wide Range ◽  
Analytical Approaches

Cutting-edge techniques have always been utilized in petroleum exploration and production to reduce costs and improve efficiencies. The demand for petroleum in the form of oil and gas is expected to increase for electricity production, transport and chemical production, largely driven by an increase in energy consumption in the developing world. Innovations in analytical methods will continue to play a key role in the industry moving forwards as society shifts towards lower carbon energy systems and more advantaged oil and gas resources are targeted. This volume brings together new analytical approaches and describes how they can be applied to the study of petroleum systems. The papers within this volume cover a wide range of topics and case studies, in the fields of fluid and isotope geochemistry, organic geochemistry, imaging and sediment provenance. The work illustrates how the current, state-of-the-art technology can be effectively utilised to address ongoing challenges in petroleum geoscience.

PETROLEUM SYSTEMS IN TASMANIA'S FRONTIER ONSHORE BASINS

2000 ◽  
Vol 40 (1) ◽  
pp. 26
Author(s):  
M.R. Bendall C.F. Burrett ◽  
H.J. Askin
Keyword(s):  
Oil And Gas ◽  
Source Rocks ◽  
Petroleum Exploration ◽  
Late Triassic ◽  
Upper Permian ◽  
Lower Permian ◽  
Peak Oil ◽  
Petroleum Systems ◽  
Upper Proterozoic ◽  
Oil Seep

Sedimentary successions belonging to three petroleum su persy stems can be recognised in and below the Late Carboniferous to Late Triassic onshore Tasmania Basin. These are the Centralian, Larapintine and Gondwanan. The oldest (Centralian) is poorly known and contains possible mature source rocks in Upper Proterozoic dolomites. The Larapintine 2 system is represented by rocks of the Devonian fold and thrust belt beneath the Tasmania Basin. Potential source rocks are micrites and shales within the 1.8 km-thick tropical Ordovician Gordon Group carbonates. Conodont CAI plots show that the Gordon Group lies in the oil and gas windows over most of central Tasmania and probably under much of the Tasmania Basin. Potential reservoirs are the upper reefal parts of the Gordon Group, paleokarsted surfaces within the Gordon Group and the overlying sandstones of the Siluro-Devonian Tiger Range and Eldon Groups. Seal rocks include shales within the Siluro-Devonian and Upper Carboniferous-Permian tillites and shales.The Gondwanan supersystem is the most promising supersystem for petroleum exploration within the onshore Tasmania Basin. It is divided into two petroleum systems— the Early Permian Gondwanan 1 system, and the Late Permian to Triassic Gondwanan 2 system. Excellent source rocks occur in the marine Tasmanite Oil Shale and other sections within the Lower Permian Woody Island and Quamby Formations of the Gondwanan 1 system and within coals and freshwater oil shales of the Gondwanan 2 system. These sources are within the oil and gas windows across most of the basin and probably reached peak oil generation at about 100 Ma. An oil seep, sourced from a Tasmanites-rich, anoxic shale, is found within Jurassic dolerite 40 km WSW of Hobart. Potential Gondwanan 1 reservoirs are the glaciofluvial Faulkner Group sandstones and sandstones and limestones within the overlying parts of the glaciomarine Permian sequence. The Upper Permian Ferntree Mudstone Formation provides an effective regional seal. Potential Gondwanan 2 reservoirs are the sandstones of the Upper Permian to Norian Upper Parmeener Supergroup. Traps consisting of domes, anticlines and faults were formed probably during the Early Cretaceous. Preliminary interpretation of a short AGSO seismic profile in the Tasmania Basin shows that, contrary to earlier belief, structures can be mapped beneath extensive and thick (300 m) sills of Jurassic dolerite. In addition, the total section of Gondwana to Upper Proterozoic to Triassic sediments appears to be in excess of 8,500 m. These recent studies, analysis of the oil seep and drilling results show that the Tasmanian source rocks have generated both oil and gas. The Tasmania Basin is considered prospective for both petroleum and helium and is comparable in size and stratigraphy to other glaciomarine-terrestrial Gondwanan basins such as the South Oman and Cooper Basins.

scholarly journals Studying Luminous Red Galaxies to probe H(z) at high redshift

2012 ◽  
Vol 8 (S295) ◽  
pp. 185-185
Author(s):  
A. Ratsimbazafy ◽  
C. Cress ◽  
S. Crawford ◽  
Keyword(s):  
High Redshift ◽  
Sloan Digital Sky Survey ◽  
Age Dating ◽  
Time Interval ◽  
Spectral Fitting ◽  
Luminous Red Galaxies ◽  
Sky Survey ◽  
Intense Burst ◽  
Red Galaxies ◽  
The Universe

AbstractLuminous Red Galaxies (LRGs) have old, red stellar populations often interpreted as evidence of a formation scenario in which these galaxies form in a single intense burst of star formation at high redshift. By measuring the average age of LRGs at two different redshifts, one can potentially measure the redshift interval corresponding to a time interval and thus measure the Hubble parameter H(z) ≈ −(1 + z)−1 Δ z/Δt (as in Jimenez & Loeb). The goal of this project is to measure directly the expansion rate of the universe at the redshift range 0.1 < z < 1.0 within 3% precision. We explore the age-dating of Sloan Digital Sky Survey LRGs using the stellar population models of Lick absorption line indices after stacking spectra in redshift bins to increase the signal-to-noise. We also use the method of full spectral fitting to measure the ages of LRGs observed with the Southern Africa Large Telescope (SALT).

Reconciling zircon and monazite thermometry constrains H2O content in granitic melts

2020 ◽  
Author(s):  
Silvia Volante ◽  
William Collins ◽  
Chris Spencer ◽  
Eleanore Blereau ◽  
Amaury Pourteau ◽  
...  
Keyword(s):  
Water Content ◽  
Volcanic Rocks ◽  
Saturation Temperature ◽  
Granitic Rocks ◽  
Zircon Geochronology ◽  
Bulk Rock ◽  
Independent Evidence ◽  
Water Values ◽  
Host Rocks ◽  
Eastern Domain

&lt;p&gt;In this contribution, we compare and test the reliability of zircon and monazite thermometers and suggest a new and independent method to constrain the H&lt;sub&gt;2&lt;/sub&gt;O content in granitic magmas from coeval zircon and monazite minerals. We combine multi-method single-mineral thermometry (bulk-rock zirconium saturation temperature (T&lt;sub&gt;zr&lt;/sub&gt;), Ti-in-zircon (T&lt;sub&gt;(Ti-zr&lt;/sub&gt;&lt;sub&gt;)&lt;/sub&gt;) and monazite saturation temperature (T&lt;sub&gt;mz&lt;/sub&gt;)) with thermodynamic modelling to estimate water content and P&amp;#8211;T conditions for strongly-peraluminous (S-type) granitoids in the Georgetown Inlier, NE Queensland. These granites were generated within ~30 km thick Proterozoic crust, and emplaced during regional extension associated with low-pressure high-temperature (LP&amp;#8211;HT) metamorphism.&lt;/p&gt;&lt;p&gt;SHRIMP U&amp;#8211;Pb monazite and zircon geochronology indicates synchronous crystallization ages of c. 1550 Ma for granitic rocks emplaced at different crustal levels&amp;#8212;from the eastern deep crustal domain (P = 6&amp;#8211;9 kbar), through the middle crustal domain (P = 4&amp;#8211;6 kbar), to the western upper crustal domain (P = 0&amp;#8211;3 kbar).&lt;/p&gt;&lt;p&gt;Bulk-rock T&lt;sub&gt;zr&lt;/sub&gt; and T&lt;sub&gt;(Ti-zr&lt;/sub&gt;&lt;sub&gt;)&lt;/sub&gt; yielded magma temperature estimates for the eastern domain of ~800&amp;#176;C and ~910&amp;#8211;720&amp;#176;C, respectively. Magma temperatures in the central and western domains were ~730&amp;#176;C (T&lt;sub&gt;zr&lt;/sub&gt;) and ~870&amp;#8211;750&amp;#176;C (T&lt;sub&gt;(Ti-zr)&lt;/sub&gt;) in the central domain, and ~810&amp;#176;C (T&lt;sub&gt;zr&lt;/sub&gt;) and ~890&amp;#8211;720&amp;#176;C (T&lt;sub&gt;(Ti-zr)&lt;/sub&gt;) in the western domain, respectively. These temperature estimates were compared with P&amp;#8211;T conditions recorded in the host rocks to determine if the magmas had equilibrated thermally with the crust. Similar temperatures were obtained for the middle and lower crust suggesting that the associated magmas thermally equilibrated at their respective depths, whereas the sub-volcanic rocks were, as expected, significantly hotter than the adjacent crust.&lt;/p&gt;&lt;p&gt;By plotting the results on a P&amp;#8211;T&amp;#8211;X&lt;sub&gt;H2O&lt;/sub&gt; petrogenetic grid, and assuming adiabatic ascent through the crust, the sub-volcanic magmas appear to be drier (~3 wt% H&lt;sub&gt;2&lt;/sub&gt;O) than the granitic magmas (~7 wt% H&lt;sub&gt;2&lt;/sub&gt;O) which formed at greater depth. Monazite saturation temperatures (which depends on the water content, light&amp;#8211;REE content and composition of the granitic melt), are in agreement with the zircon thermometers only if water values of ~3 wt% H&lt;sub&gt;2&lt;/sub&gt;O and ~7 wt% H&lt;sub&gt;2&lt;/sub&gt;O are assumed for the upper crustal magmas and deeper magmas, respectively. Moreover, melt compositions extracted from a modelled pseudosection of a sillimanite-bearing metapelite, which was interpreted to be the typical source rock for the surrounding granites (P=5 kbar and T=690&amp;#176;C&amp;#8211;850&amp;#176;C), show comparable water content values.&lt;/p&gt;&lt;p&gt;The T&lt;sub&gt;mz&lt;/sub&gt; results provide independent evidence for the H&lt;sub&gt;2&lt;/sub&gt;O content in magmas, and we suggest that reconciling T&lt;sub&gt;zr&lt;/sub&gt; with T&lt;sub&gt;mz&lt;/sub&gt; is a new and independent way of constraining H&lt;sub&gt;2&lt;/sub&gt;O content in granitic magmas.&lt;/p&gt;

scholarly journals Ocena wpływu nasuwającego się górotworu karpackiego na przebieg procesów naftowych w utworach jego podłoża w rejonie Rzeszowa

Nafta-Gaz ◽  
2021 ◽  
Vol 77 (6) ◽  
pp. 351-365
Author(s):  
Karol Spunda ◽  
◽  
Tomasz Słoczyński ◽  
Krzysztof Sowiżdżał ◽  
◽  
...  
Keyword(s):  
Tectonic Evolution ◽  
Geological Structure ◽  
Source Rocks ◽  
Petroleum Exploration ◽  
Special Role ◽  
Petroleum Systems ◽  
Geological Processes ◽  
Lower Palaeozoic ◽  
Outer Carpathians

The article presents the concept of petroleum systems modeling in the area with complex fold-thrust belt structure. The aim of the study was to verify the views on the influence of the overtrusting Carpathian orogen on the course of petroleum processes in the basement (Meso-Palaeozoic) formations. The project was implemented in the marginal zone of the Skole Unit (Outer Carpathians) overlapping various structural and tectonic units of the basement. The area of Rzeszów city was selected as it presents adequate complexity of the geological structure to meet assumed methodological objectives of the project and, at the same time, provides relatively vast amount of geological data available which creates a conditions for a comprehensive approach. The study was carried out using the Dynel 2D and PetroMod 2D software. The course of the structural and tectonic evolution of the area was reconstructed in 5 stages, the results of which were subsequently applied in a dynamic modeling of the petroleum systems. The modeling results made it possible to recreate and analyze the course of a complex geological processes, the effects of which are manifested, among others, by the time and amounts of generated hydrocarbons as well as the dynamics of expulsion, migration and accumulation processes. The results show the course of petroleum processes in each stage of the petroleum basin evolution, revealing a special role of thrust tectonic of Outer Carpathians on basement formations. For the adopted assumptions of the structural and tectonic evolution, the generation of hydrocarbons by Lower Palaeozoic source rocks was initiated with the overthrusting of the Carpathians. This increases the chances of their accumulation in reservoir intervals sealed by an overthrusting orogen. This is a positive premise in the context of petroleum exploration in the area.

scholarly journals The deformation and granitisation of Ketilidian rocks in the Nanortalik area, S. Greenland

1966 ◽  
Vol 59 ◽  
pp. 1-102
Author(s):  
A Escher
Keyword(s):  
Volcanic Rocks ◽  
Time Interval ◽  
Chemical Analyses ◽  
Intrusive Body ◽  
Major Phase ◽  
Fine Grained ◽  
Field Evidence ◽  
Rigid Mass ◽  
Metasomatic Replacement ◽  
Subsequent Replacement

The Nanortalik peninsula, situated between the fjords of Tasermiut and Sarqâ, is largely composed of Ketilidian schists, quartzites and volcanic rocks. All these rocks are more or less strongly folded. The folding took place probably in three successive phases during the Ketilidian period : A first deformation resulting in folds with NNE trending axes, was followed by a second major phase of folding with NW axes. This second folding was essentially plastic. A third deformation, acting probably on a more rigid mass, was characterised by the formation of fracturec1eavage. Third-period folds possess very long wavelengths; their axes are oriented NNE to NE. Migmatisation started probably during the second deformation period resulting in the formation of many dykes and veins of pegmatite and aplite. Four generations of Ketilidian pegmatites can be recognised. Most of them appear to have been formed by metasomatic replacement. It seems that during the Ketilidian orogeny, the evolution of the schists and gneissic schists tended to a granodioritic composition. Potassium metasomatism only became active at the end of the Ketilidian period. In the NE part of the Nanortalik peninsula, three Sanerutian granites can be observed. These granites are similar in composition (quartz-microline-biotite), but possess different ages and textures. The time interval between the last Ketilidian deformation and the emplacement of the first Sanerutian granite was marked by the intrusion of several metadoleritic dykes. The first and principal Sanerutian granite usually shows an indistinct foliation due to numerous oriented inc1usions. Field evidence indicates that this granite was formed mainly by replacement of volcanic rocks. Chemical analyses show that large amounts of K, Si and Na have been supplied to produce the granitisation of the volcanic rocks. The second Sanerutian granite is characterised by a coarse porphyroblastic texture and appears to have been emplaced partially by the intrusion of a melt and partially by a subsequent replacement of the host-rock. Finally, the last Sanerutian granite displays all the characteristics of a pure intrusive body. It is generally very fine-grained and forms many cross-cutting dykes.

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