The Castanhão Reservoir, NE Brazil: Reservoir-Triggered Seismicity in secondary transtensional tectonic settings within a major strike-slip system

Clicks: 8
ID: 331973
2026
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #331 of 338 articles by views in geophysical journal international

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 338 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Summary We investigate Reservoir-Triggered Seismicity (RTS) associated with the Castanhão Reservoir in northeastern Brazil, located within an intraplate region. Using continuous waveform data from a local seismic network (2009–2010), we construct a high-resolution earthquake catalogs of 227 events through template matching (PyMPA) and probabilistic location methods, with subsequent double-difference relocation improving spatial resolution for 103 events. The seismicity forms two clusters delineating a steeply dipping (∼80°) fault zone characterized as a reactivated strike-slip system with secondary transtensional/stepover structures within the Jaguaribe Shear Zone corridor, with moment magnitudes ranging from Mw 0.0 up to Mw 2.7. To assess triggering mechanisms, we model pore-pressure diffusion induced by reservoir impoundments. The estimated hydraulic diffusivity (∼0.080 m²/s) and spatiotemporal evolution of seismicity indicate a response governed by fluid pressure diffusion. Pore-pressure increases on the order of tens of kPa are sufficient to activate critically stressed fault segments, consistent with previous RTS observations. The seismic sequence exhibits swarm-like behavior, interpreted as progressive, fluid-driven rupture within a segmented fault network. We further analyze the temporal evolution of seismic strain using Seismic Strain Dynamics (SSD) and seismic regularity (dc) metrics, revealing patterns consistent with a multi-stage earthquake preparatory process. The largest event in the main cluster (Mw 2.1) occurs during a late-stage failure phase, following prolonged fault conditioning. Our results highlight the role of reactivated, critically stressed secondary strike-slip fault networks as hydraulically favorable conduits for pore-pressure diffusion and RTS. The study demonstrates that even moderate pore-pressure perturbations can induce delayed, swarm-type seismicity in intraplate settings, emphasizing the importance of integrating geological structure, hydromechanical processes, and seismic monitoring for improved hazard assessment near large reservoirs.
Reference Key
openalex_W7221174254 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Helena Ciechowska, Beata Orlecka‐Sikora, Łukasz Rudziński, Aderson do Nascimento, José Augusto Fonsêca, Alessandro Vuan
Are you one of these authors? Claim your profile
Journal geophysical journal international
Year 2026
DOI
10.1093/gji/ggag431
URL
https://doi.org/10.1093/gji/ggag431
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.