Results 41 to 50 of about 186 (126)

The research of LWD acoustic isolator based on SAW spatial separation [PDF]

MATEC Web of Conferences, 2019
Acoustic logging while drilling (LWD) can extract P-wave and S-wave information from the formation. However, the transmission of the collar wave propagated directly from the emitter to the receiver may interfere with the P-wave and S-wave and affect the ...
Yang Peinian, Chen Dehua, Xiuming Wang
doaj   +1 more source

Dissociating Gas Hydrate Beneath the Hydrate Stability Zone

Geophysical Research Letters, Volume 52, Issue 13, 16 July 2025.
Abstract Vast amounts of carbon are stored beneath the seafloor in the form of methane hydrate. Hydrate is stable at moderate pressure and low temperature at a depth extending several hundred meters beneath the seafloor to the base of gas hydrate stability (BGHS) often marked by bottom simulating reflections (BSRs) in seismic profiles.
I. A. Pecher, A. E. Cook, E. A. Solomon, X. Wang, S. Han, M. Paganoni, M. Luo, K. U. Heeschen, D. D. McNamara, M. Nole, L. LeVay, K. Petronotis, P. M. Barnes, L. M. Wallace, D. M. Saffer   +14 more
wiley   +1 more source

A theoretical analysis of the logging-while-drilling dipole acoustic reflection measurement

Frontiers in Earth Science
Post-drilling wireline acoustic single-well imaging technology can now detect geological structures tens of meters away from boreholes. Further development of this single-well imaging technology in the logging-while-drilling (LWD) environment will have ...
Yanghu Li, Yanghu Li, Zhenlin Wang, Zhenlin Wang, Yuanda Su, Xiaoming Tang   +5 more
doaj   +1 more source

State of Stress Across Major Faults in the Nankai Subduction Zone Estimated From Wellbore Breakouts

Journal of Geophysical Research: Solid Earth, Volume 130, Issue 7, July 2025.
Abstract Quantifying the orientation and magnitude of stress at tectonically active margins and along major fault systems is integral to understanding the mechanics of faulting and earthquakes. Here we use data collected as part of the IODP (Integrated Ocean Drilling Program) Nankai Trough Seismogenic Zone Experiment to constrain in situ stress ...
Kaitlin E. Schaible, Demian M. Saffer
wiley   +1 more source

Near Steady Late Pleistocene Tropical Denudation Rates in SW Madagascar

Journal of Geophysical Research: Earth Surface, Volume 130, Issue 7, July 2025.
Abstract Denudation is a key parameter controlling the evolution of the Earth's surface, the production of soils, the stability of relief, or the long‐term evolution of climate. Climate fluctuations conversely have a strong impact on denudation, but these complex feedback mechanisms are still under‐constrained.
Etienne Large, Julien Charreau, Pierre‐Henri Blard, Germain Bayon, Eduardo Garzanti, Bernard Dennielou, Gwenaël Jouet, Natalia Vazquez Riveiros, Jacques Giraudeau, Laurie Reisberg, Aimeryc Shcumacher, Alfred Andriamamonjy, Amos Fety Michel Rakotondrazafy   +12 more
wiley   +1 more source

Research on calculation method of BI by logging while drilling of shale reservoirs: A case of Qiongzhusi formation in Cambrian, Weiyuan area

Youqicang pingjia yu kaifa, 2018
As a new parameter of the rock mechanics evaluation, the brittleness index （BI） has an important influence on the later fracturing and reconstruction of the reservoirs.
Wang Hanwei, Xia Hongquan, Liu Chang, Zhao Hao   +3 more
doaj  

Development of Eccentric Transmitter Transducer for LWD Acoustic Remote Detection

Cejing jishu
To address the challenge that traditional logging while drilling (LWD) acoustic transducers lack directional radiation capability, hindering the identification of geological structures outside the borehole in drilling environments, this study developed ...
SUN Zhifeng, QIU Ao, LIU Xien, LUO Bo, LI Jie, ZHAO Han   +5 more
doaj   +1 more source

Unlocking the Style and Timing of Submarine Landslides: Insights From the Tuaheni North Slide, Hikurangi Margin

Geophysical Research Letters, Volume 52, Issue 9, 16 May 2025.
Abstract We investigate the morphology and timing of Tuaheni North, a large submarine landslide within the Tuaheni Landslide Complex on Aotearoa New Zealand's Hikurangi Margin. We show a clear correlation between two major source volumes from Tuaheni North and two downslope mass transport deposits (MTDs), suggesting there were two distinct events ...
Alexey Portnov, Jess I. T. Hillman, Sally Watson, Ann E. Cook, Andreas Laake, Francisco José Lobo   +5 more
wiley   +1 more source

Recent Advances in the Use of Drill Cuttings for Determining Subduction Zone Structure, Stratigraphy, and Stress State

Geochemistry, Geophysics, Geosystems, Volume 26, Issue 5, May 2025.
Abstract Obtaining in situ samples from active subduction systems is critical for assessing the material properties and geological evolution of rocks and sediments that host plate boundary deformation, and advancing our understanding of the processes that lead to fault locking and rupture.
P. H. Cornard, A. M. Schleicher, C. Regalla, M. Hamahashi, M. Kitamura, R. Fukuchi, K. T. Pickering, H. Kitajima, T. Wiersberg   +8 more
wiley   +1 more source

High‐magnification platform for characterising microscopic communities

Methods in Ecology and Evolution, Volume 16, Issue 4, Page 715-721, April 2025.
Abstract Characterising microscopic communities is important for both ecological research and diagnostic applications. In these areas, light microscopy is still a fundamental tool due to its accessibility and real‐time imaging capabilities. However, the higher magnifications required for accurate identifications typically necessitates extensive sample ...
Gerhard du Preez
wiley   +1 more source