Precambrian rift-related magmatism and sedimentation, south Victoria Land, Antarctica

2007 ◽  
Vol 19 (4) ◽  
pp. 471-484 ◽  
Author(s):  
Y.A. Cook
Keyword(s):  
Oceanic Crust ◽  
Volcanic Activity ◽  
Igneous Rocks ◽  
Source Rocks ◽  
Main Body ◽  
Quartz Syenite ◽  
Continental Extension ◽  
Victoria Land ◽  
First Time ◽  
Marine Basin

AbstractPrecambrian continental extension is described in detail for the first time in the Victoria Land segment of the Transantarctic Mountains and is comparable with plume related intercontinental rifting of the Afar area, Africa. The Baronick Formation comprises igneous-derived conglomerate, marble and volcanic to sub-volcanic igneous layers. Volcanic and carbonate horizons were eroded in a fluvial or marine environment and provided debris for mass flow and slump deposits which formed in a marginal marine basin in the Precambrian. Clasts in these deposits include basalt, trachyte and comendite, and along with the interbedded volcanic layers of basalt, trachyte and quartz syenite, indicate proximity and contemporaneity of volcanic activity. Igneous layers and source rocks for clasts of the Baronick Formation have an enriched MORB chemistry and underwent albitization of calcic feldspar before erosion and conglomerate deposition. The Highway Suite forms a kilometre-scale body of gabbro and dolerite plugs and is interpreted as a slice of transitional continental oceanic crust. The chemistry of all igneous rocks suggests a continental rift environment and the associated sediments are consistent with such a setting. The Baronick Formation was locally intruded by sills of the Highway Suite; however, the main body of the Highway Suite was juxtaposed against the Baronick Formation during greenschist facies shearing before c. 551 Ma.

scholarly journals LINGKUNGAN DAN EVOLUSI TEKTONIK BATUAN DAN SEDIMEN BERDASARKAN UNSUR KIMIA UTAMA DI PERAIRAN BAYAH DAN SEKITARNYA, PROVINSI BANTEN

2016 ◽  
Vol 12 (3) ◽  
pp. 125
Author(s):  
Ediar Usman ◽  
Udaya Kamiludin
Keyword(s):  
Oceanic Crust ◽  
Major Elements ◽  
Igneous Rocks ◽  
Source Rocks ◽  
Calc Alkaline ◽  
Triangular Diagram ◽  
Sediment Samples ◽  
Tectonic Environment ◽  
Continental Arc ◽  
Magma Series

Pengeplotan data unsur kimia pada diagram SiO2 vs K2O untuk sampel sedimen dasar laut cenderung terjadi kenaikan SiO2 dan penurunan K2O, sehingga arah evolusi berkembang dari kalk-alkalin sedang ke kalk-alkalin rendah (toleitik). Pada sampel batuan beku dan sedimen hasil pemboran memperlihatkan pola evolusi magma sebaliknya, terjadi kenaikan SiO2 dan K2O dalam seri magma yang sama (toleitik). Kondisi ini diperkuat oleh diagram segitiga AFM (A = Na2O+K2O; F = FeOtotal ; M = MgO) yang menunjukkan sebagian besar sampel yang diplot berada antara toleitik dan kalk-alkalin sedang. Hasil ini memberi kesimpulan bahwa batuan ini bersifat transisi antara toleitik dan kalk-alkalin sedang, dan condong ke arah seri toleitik sebagai indikasi batuan berasal dari daerah samudera. Berdasarlan pengeplotan pada diagram segitiga TiO2 – 10MnO – P2O5, lingkungan tektonik batuan beku di pantai Cibobos, sedimen dasar laut dan sedimen pemboran pada umumnya berada pada lingkungan tektonik andesit kepulauan samudera dan sebagian busur benua. Hasil tersebut, maka dapat disimpulkan bahwa sedimen di daerah Bayah berhubungan dengan seri magma dengan afinitas rendah mulai toleitik hingga kalk-alkalin sedang dan batuan samudera yang menyusup ke busur kepulauan atau busur benua. Hasil ini dapat mengetahui lingkungan dan evolusi batuan sumber sehingga diharapkan bermanfaat dalam kegiatan ekplorasi sumber daya mineral dan energi di masa mendatang. Kata kunci: unsur kimia utama, lingkungan tektonik, evolusi, kerak samudera dan kontinen, perairan Bayah Plotting of major elements data of the seafloor sediment samples on diagram of SiO2 vs K2O tends to increase the SiO2 and decrease the K2O, therefore the direction of evolution develop from medium to low calc-alkaline (tholeitic). From igneous rocks and drilling sediment samples shows that the evolution magma has the opposite pattern, increasing of SiO2 and K2O in the same magma series ( tholeitic). This condition is confirmed by the triangular diagram of AFM (A = Na2O+K2O; F = FeOtotal ; M = MgO) that shows the most of plotted samples are between medium calc-alkaline and tholeitic. This result give a conclusion that these rocks are at transitional area between tholeitic and medium calc-alkaline, and tend towards tholeitic series as an indication of rocks from oceanic zone. Based on plotting on the triangular diagram of TiO2 - 10MnO - P2O5, tectonic environment of igneous rocks in the coast of Cibobos, surface and drilling sediment samples, in general these samples are in the tectonic environment of oceanic islands andesite and partial of continental arc. From this study, it can be concluded that the sediment in the Bayah area is associated with affinity magma series from low kalk-alkaline (tholeitic) to medium calc-alkaline, and oceanic crust is being subducting to continental arc. This result could recognize the environment and the evolution of source rocks, therefore it may useful in the exploration activities of mineral and energy resources in the future. Keywords: major elements, tectonic environment, evolution, continental and oceanic crust, Bayah waters.

Stratigraphic position and localities of the Temlyan flora from the Anadyr river lower course basin

Palaeobotany ◽  
2015 ◽  
Vol 6 ◽  
pp. 48-67 ◽  
Author(s):  
L. B. Golovneva ◽  
A. A. Grabovskiy
Keyword(s):  
Volcanic Activity ◽  
City Area ◽  
Plant Fossils ◽  
Stratigraphic Position ◽  
Early Paleocene ◽  
First Time ◽  
Systematic Composition ◽  
Stratigraphic Range

Plant fossils from the volcano-clastic deposits of the lower part of the Tanyurer Formation and lower part of the Tavaivaam Unit in the Anadyr city area (Northeastrn Russia) are described for the first time. This assemblage was named as the Temlyan flora. It consists of 25 taxa and includes ferns, horsetails, lycophytes, ginkgoaleans, czekanowskialeans, cycadophytes, conifers and angiosperms. The Temlyan flora is similar in systematic composition to the Rarytkin flora from the upper part of the Rarytkin Formation which was dated as the late Maastrichtian-Danian. But it is distinguished from the latter by presence of the numerous relicts (Lokyma, Nilssonia, Encephalartopsis, Phoenicopsis and Ginkgo ex gr. sibirica). Probably the presence of relicts in the Temlyan flora is connected with influence of volcanic activity. Age of the Temlyan flora is determined as the late Maastrichtian-Danian on the basis of systematic similarity with the Rarytkin Flora. However this age may be slightly younger, possibly only early Paleocene, because the Tanyurer Formation superposes the Rarytkin Formation. Stratigraphic range of Lokyma, Nilssonia, Encephalartopsis, Phoenicopsis and Ginkgo ex gr. sibirica is extended from its previously known latest records in the early Campanian or middle Maastrichtian up to as late as the latest Maastrichtian or early Paleocene. It is very possible, that these typical Mesozoic taxa may have persisted into the Paleogene.

Specifics of the Caledonian Collision in the Ol’khon Region (Lake Baikal, Russia)

2021 ◽  
Vol 62 (4) ◽  
pp. 389-400
Author(s):  
V.A. Makrygina
Keyword(s):  
Subduction Zone ◽  
Oceanic Crust ◽  
Lake Baikal ◽  
Siberian Craton ◽  
Island Arc ◽  
Geophysical Data ◽  
Igneous Rocks ◽  
Fold Belt ◽  
Adjacent Part

Abstract —Analysis of geochemical, geochronological, and new geophysical data on metasedimentary and igneous rocks of the Ol’khon region has made it possible to substantiate: (1) the absence of products of the Caledonian suprasubduction magmatism from the adjacent part of the Siberian craton and (2) the presence of a product of this magmatism in the Anga–Talanchan island arc, namely, the Krestovsky massif with gabbro-diorite to granite phases. This suggests subduction of the Paleoasian oceanic crust under the island arc before the collision. The geophysical data showed a steep sinking of the Siberian craton margin. This sinking and the supposed contrary movement and rotation of the Siberian craton prevented the appearance of a subduction zone beneath the craton during the collision but caused the wide development of fault plates in the fold belt at the late collision stage. The residue of oceanic crust slab was pressed out along the fault planes near the surface and formed a row of gabbro-pyroxenite massifs of the Birkhin Complex in the fold belt, where syncollisional granitic melts (Sharanur Complex) formed at the same time. The interaction of two contrasting melts gave rise to the Tazheran and Budun alkaline syenite massifs and alkaline metasomatites of the Birkhin and Ulanganta gabbroid massifs.

Revised stratigraphy of the Mesozoic rocks of southern Cyprus

1980 ◽  
Vol 117 (6) ◽  
pp. 547-563 ◽  
Author(s):  
R. E. Swarbrick ◽  
A. H. F. Robertson
Keyword(s):  
Oceanic Crust ◽  
Continental Margin ◽  
Late Cretaceous ◽  
Sedimentary Cover ◽  
Igneous Rocks ◽  
Late Triassic ◽  
Metamorphic Rocks ◽  
Southern Cyprus

SummaryRecent resurgence of interest in the Mesozoic rocks of SW and southern Cyprus necessitates redefinition of the Mesozoic sedimentary and igneous rocks in line with modern stratigraphical convention. Two fundamentally different rocks associations are present, the Troodos Complex, not redefined, a portion of late Cretaceous oceanic crust, and the Mamonia Complex, the tectonically dismembered remnants of a Mesozoic continental margin. Based on earlier work, the Mamonia Complex is divided into two groups, each subdivided into a number of subsidiary formations and members. The Ayios Photios Group is wholly sedimentary, and records the evolution of a late Triassic to Cretaceous inactive continental margin. The Dhiarizos Group represents Triassic alkalic volcanism and sedimentation adjacent to a continental margin. Several other formations not included in the two groups comprise sedimentary mélange and metamorphic rocks. The Troodos Complex possesses an in situ late Cretaceous sedimentary cover which includes two formations of ferromanganiferous pelagic sediments, radiolarites and volcaniclastic sandstones. The overlying Cainozoic calcareous units are not redefined here.

scholarly journals Composition Changes of Hydrocarbons during Secondary Petroleum Migration (Case Study in Cooper Basin, Australia)

Geosciences ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 78 ◽  
Author(s):  
Sara Borazjani ◽  
David Kulikowski ◽  
Khalid Amrouch ◽  
Pavel Bedrikovetsky
Keyword(s):  
Capture Rate ◽  
Pulse Generation ◽  
Source Rocks ◽  
Deep Bed Filtration ◽  
Concentration Difference ◽  
Petroleum Migration ◽  
Compositional Grading ◽  
First Time ◽  
Composition Changes

The reliable mathematical modelling of secondary petroleum migration that incorporates structural geology and mature source rocks in the basin model, allows for prediction of the reservoir location, yielding the significant enhancement of the probability of exploration success. We investigate secondary petroleum migration with a significant composition difference between the source and oil pools. In our case study, the secondary migration period is significantly shorter than the time of the hydrocarbon pulse generation. Therefore, neither adsorption nor dispersion of components can explain the concentration difference between the source rock and the reservoir. For the first time, the present paper proposes deep bed filtration of hydrocarbons with component kinetics retention by the rock as a physics mechanism explaining compositional grading. Introduction of the component capture rate into mass balance transport equation facilitates matching the concentration difference for heavy hydrocarbons, and the tuned filtration coefficients vary in their common range. The obtained values of filtration coefficients monotonically increase with molecular weight and consequently affects the size of the oleic component, as predicted by the analytical model of deep bed filtration. The modelling shows a negligible effect of component dispersion on the compositional grading.

Recycling of Paleo-oceanic crust: Geochemical evidence from Early Paleozoic mafic igneous rocks in the Tongbai orogen, Central China

Lithos ◽  
2019 ◽  
Vol 328-329 ◽  
pp. 312-327 ◽  
Author(s):  
Fei Zheng ◽  
Li-Qun Dai ◽  
Zi-Fu Zhao ◽  
Yong-Fei Zheng ◽  
Zheng Xu
Keyword(s):  
Oceanic Crust ◽  
Igneous Rocks ◽  
Central China ◽  
Early Paleozoic ◽  
Geochemical Evidence

An Isolated Occurrence of Igneous Rocks at Gorei in the Las Anod District of the Somaliland Protectorate

1957 ◽  
Vol 94 (6) ◽  
pp. 498-502 ◽  
Author(s):  
J. E. Mason
Keyword(s):  
Igneous Rocks ◽  
Present Contribution ◽  
Quartz Syenite ◽  
Field Evidence ◽  
True Relationship

AbstractThe quartz-syenite outcrop in the Las Anod District of the Somaliland Protectorate has been known for at least twenty-three years, but the true relationship between it and the overlying Cretaceous sediments has not been clearly resolved. Some geologists have said that the igneous rocks are overlain unconformably by the Cretaceous, whilst others have said that they intrude the Cretaceous. The present contribution brings forward field evidence to confirm the former view.

A New Approach to Kinematics Modelling of Snake-Robot Concertina Locomotion

2011 ◽  
Vol 110-116 ◽  
pp. 2786-2793
Author(s):  
Alireza Akbarzadeh ◽  
Jalil Safehian ◽  
Javad Safehian
Keyword(s):  
The Body ◽  
Function Parameter ◽  
Future Research ◽  
Main Body ◽  
New Approach ◽  
Snake Robot ◽  
Modelling Method ◽  
Dynamic Function ◽  
Basic Characteristics ◽  
First Time

In this paper, for the first time, kinematics modelling of snake robot travelling with concertina locomotion is presented. Next a novel kinematics modelling method is presented which has an advantage of allowing natural snake like locomotion. During concertina motion, certain parts of the body contract, expand or do not change their shape. This results into having different body curves for different parts of a snake. To simulate this, first we introduce a mathematical equation, called dynamic function, in which by varying a certain function parameter, body curve during motion is realized. To obtain concertina gait, the snake body is divided into three different modules, head module, tail module and main body module that connects the head to the tail module. Each module forms a specific curve which can be modelled using the proposed dynamic function. At each moment during snake locomotion, the kinematics of different links can be derived by fitting links to the body curve. Finally concertina locomotion is simulated using Webots software. Results indicate concertina locomotion can be obtained. Furthermore, the proposed dynamic function requires relatively lower computation requirement. Therefore, adaption of body curve to other real snake like gaits as well as mixed type locomotion is made possible. This works represents a first approach to a simulation of a snake-like mechanism in order to get basic characteristics of such locomotion and to enable our future research.

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