Seismicity Triggering in the North Delaware Basin, West Texas, USA
Description:
As part of the intraplate tectonic regime within the continental US, the seismicity rate in Texas is expected to be low. However, the seismicity rate in West Texas has steadily increased since 2009, and significantly accelerated since 2020. Notably, the Texas Seismological Network (TexNet) has reported 49 M≥4 earthquakes (all after 2020) and 3 M≥5 earthquakes (all after 2022). In the area of the North Delaware basin of Texas, the first M4+ earthquake (2020-02-18, 13:28:06) occurred in the area of Mentone, followed one month later by a main event (M4.9; 2020-03-26, 15:16:27). The seismogenic structure that hosts the Mentone cluster is a normal fault striking WSW-ENE, with the seismicity distributed around or above the basement. The presence of nearby long-term deep wastewater injection in the area strongly suggests that the seismicity is due to the oil and gas operations.
In contrast, ~11km to the southeast of the Mentone cluster, seismicity with its first M3+ earthquake on Jan 25th 2021, shows a complex, normal faulting system near the area of Coalson Draw. Since then, the Coalson Draw seismic zone has been very active, with two notable M5+ events (M5.4, 2022-11-16 21:32:44 & M5.2 2023-11-08 10:27:49 ). The seismicity is apparently spanning ~5 km in depth and stretching across the basin-basement interface at about 5 km depth. Following an increase of seismicity in September 2021 (6 M4+ events occurred between September 3rd and October 3rd, 2021), in October 2021 the injection volume has been reduced at approximately 20 km to the north of the Coalson Draw sequence, due to concerns of deep injection being the causal factor of seismicity in the area. Additionally, the hypocenter of the M4.9 Mentone event is closer (~11km) to the deep injection than the Coalson Draw sequence (~20km). These relations suggest that the Coalson Draw sequence might have been initiated by deep wastewater injection, and later the seismicity rate has accelerated (M3+ events) due to dynamic triggering mechanisms (i.e., earthquake-to-earthquake triggering), eventually resulting in the occurrence of the first M5+ event.
Session: Induced Earthquakes: Source Characteristics, Mechanisms, Stress Field Modeling and Hazards - II
Type: Oral
Date: 5/1/2024
Presentation Time: 10:45 AM (local time)
Presenting Author: Alexandros
Student Presenter: No
Invited Presentation:
Authors
Alexandros Savvaidis Presenting Author Corresponding Author alexandros.savvaidis@beg.utexas.edu University of Texas at Austin |
Anthony Lomax alomax@free.fr ALomax Scientific |
Guo-Chin Huang dino.huang@beg.utexas.edu University of Texas at Austin |
Yangkang Chen yangkang.chen@beg.utexas.edu University of Texas at Austin |
Natalie Alvarez natalva@utexas.edu University of Texas at Austin |
Jessica Domino jessica.domino@texnetops.org University of Texas at Austin |
Grace Burke grace.burke@austin.utexas.edu University of Texas at Austin |
Fernando Ferrer fernando.ferrer@texnetops.org University of Texas at Austin |
Daniel Siervo daniel.siervo@beg.utexas.edu University of Texas at Austin |
Victor Salles victor.salles@beg.utexas.edu University of Texas at Austin, Austin, Texas, United States |
Preston Fleck preston.fleck@beg.utexas.edu University of Texas at Austin, Austin, Texas, United States |
Bede Uku bede.uku@beg.utexas.edu University of Texas at Austin, Austin, Texas, United States |
Cooper McCabe cooper.mccabe@beg.utexas.edu University of Texas at Austin, Austin, Texas, United States |
Vincent J O'Sullivan vincent.osullivan@beg.utexas.edu University of Texas at Austin, Austin, Texas, United States |
Seismicity Triggering in the North Delaware Basin, West Texas, USA
Category
Induced Earthquakes: Source Characteristics, Mechanisms, Stress Field Modeling and Hazards