Results 21 to 30 of about 2,604 (197)

The Late Great Unconformity of the Central Canadian Shield

Geochemistry, Geophysics, Geosystems, 2021
The Great Unconformity is a widely distributed surface separating Precambrian rocks from overlying Phanerozoic sedimentary sequences. The causes and implications of this feature, and whether it represents a singular global event, are much debated.
C. P. Sturrock, R. M. Flowers, F. A. Macdonald   +2 more
doaj   +1 more source

Onshore-offshore patterns in Late PreCambrian and Lower Palaeozoic trace fossils [PDF]

The Paleontological Society Special Publications, 1992
There was a dramatic increase in abundance and diversity of trace fossils in Upper Precambrian and Lower Cambrian shallow water seas. The trace-producing animals rapidly filled all the available niches and in low energy, muddy, environments they evolved winding, meandering and patterned habits. Traces such as Taphrhelminthopsis, Helminthoida, Nereites,
T. Peter Crimes, N. Chris Hunt
openaire   +1 more source

Vendian age of igneous rocks of the Chamberlain valley area (Northern part of the Wedel Jarlsberg Land, Svalbard Archipelago)

Записки Горного института, 2022
The geological structure, structural relations with the underlying complexes, mineral composition, age and origin of sedimentary-volcanogenic and intrusive formations of the Chamberlain valley area (northern part of the Wedel Jarlsberg Land, Svalbard ...
Aleksandr N. Sirotkin, Aleksandr N. Evdokimov   +1 more
doaj   +1 more source

On some aspects of the study of age ratios of rock complexes of the Ukrainian Shield

Геофизический журнал, 2020
The article discusses the applicability of stratigraphic dismemberment in the study of high-temperature metamorphic complexes of the Ukrainian Shield. The effectiveness of the stratigraphic method with respect to these complexes was called into question
V.P. Kyrylyuk
doaj   +1 more source

Major engineering breakthrough of Well XA‐1, the deepest ten‐thousand‐meter well in a global sedimentary basin

Deep Underground Science and Engineering, EarlyView.
Well XA‐1, completed at a true vertical depth of 11 156 m in the Shawan Sag of the Junggar Basin, is the deepest predominantly near‐vertical well drilled in a sedimentary basin. The figure shows the basin's tectonic framework and well location (a), a structural cross‐section spanning the Shawan Sag and adjacent uplifts (b), and the stratigraphic column
Fangkai Liu, Qingwen Tan, Sen Zhu, Guangyou Zhu   +3 more
wiley   +1 more source

Deep crustal structure of the southern Baltic Sea in the light of seismic and potential field data [PDF]

Solid Earth
The southern Baltic Sea lies within a critical transitional zone between two major geological provinces of Europe: the Precambrian East European Platform and the Palaeozoic Platform of Western Europe.
M. Ponikowska, S. Stovba, S. Stovba, M. Malinowski, M. Malinowski, Q. Nguyen, S. Mazur   +6 more
doaj   +1 more source

Groundwater Occurrence in the Lower Palaeozoic and Precambrian Rocks of the UK: Implications for Source Protection [PDF]

Water and Environment Journal, 1999
ABSTRACTLower Palaeozoic and Precambrian rocks are distributed in Scotland, Northern Ireland, Cumbria, Wales and the Channel Islands, and coincide largely with upland areas. Groundwater flow and storage is mostly shallow and flow paths are short, although there is some limited deeper groundwater circulation.
openaire   +2 more sources

World's fastest 10 000‐m breakthrough: The XY‐22 well redefines deep‐earth access in the Tarim Basin

Deep Underground Science and Engineering, EarlyView.
The Tarim Basin in northwestern China hosts one of the world's deepest petroleum systems, exemplified by the XY‐22 ultra‐deep well (bottom depth: 11 116 m; ~220°C, ~145 MPa). This study integrates tectonic mapping, geological cross‐sections, ultraviolet fluorescence microscopy, and optical photothermal infrared (OPTIR) spectroscopy to characterize ...
Qingwen Tan, Fangkai Liu, Sen Zhu, Guangyou Zhu, Haiping Huang   +4 more
wiley   +1 more source

Stratigraphic schemes of the Precambrian of the Ukrainian Shield (analytical review)

Мінеральні ресурси України
The first stratigraphic schemes of the Precambrian of the Ukrainian Shield were compiled in 1926 by V. I. Luchytskyi and D. M. Sobolev, and were subsequently developed by numerous authors until 1967.
V. P. Kyrylyuk
doaj   +1 more source

Modeling and monitoring injectivity evolution during cold CO2 injection with field evidence from aquistore carbon capture and storage operations

Deep Underground Science and Engineering, EarlyView.
This work integrates 5 years of field data from the Aquistore CCS project with a non‐isothermal THM modeling framework to explain how cold CO2 injection alters injectivity over time. The study shows that sustained cooling near the wellbore reduces effective stresses, promotes tensile micro‑cracking, and leads to semi‑reversible permeability enhancement
Alireza Rangriz Shokri, Stephen Talman, Erik Nickel, Rick Chalaturnyk   +3 more
wiley   +1 more source