Current Land Subsidence And Fault Movement In The Long Point Fault Area

Land subsidence driven by groundwater withdrawal has affected the greater Houston region for over a century, posing ongoing risks to infrastructure and urban development. This study investigates fault activity along the Long Point Fault (LPF) and characterizes surrounding land subsidence using a combined GPS and Sentinel-1 InSAR approach spanning 2013-2026. Continuous and campaign-style GPS displacement time-series from eleven LPF network stations, processed within the Gulf of Mexico 25 (GOM25) stable geodetic reference frame, are analyzed for full-record and recent-period (2018-2026) velocity estimates and compared against the 2013-2018 baseline established by Liu et al. (2019). LiCSBAS-derived InSAR vertical and EW horizontal velocity fields for the 2017-2025 period were anchored to GOM25 GPS velocities, providing spatially continuous deformation maps across the study area. GPS results confirm that the Long Point Fault remains inactive during the study period, with no resolvable differential velocity contrast between hanging wall and footwall station pairs attributable to fault slip. Horizontal velocity vectors exhibit coherent northwestward motion consistent with gravitational spreading toward the Jersey Village subsidence bowl, with no systematic directional discontinuity across the fault trace. The GPS-anchored InSAR velocity fields corroborate this finding, showing no discernible surface expression of fault-related deformation. These findings confirm the continued inactivity of the Long Point Fault through 2026 and demonstrate that observed surface deformation is dominated by spatially variable aquifer-system compaction rather than fault-related strain. Network-wide subsidence rates have declined relative to the 2013-2018 period, supporting the effectiveness of HGSD groundwater regulation in reducing subsidence across the greater Houston area.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

XMASTERS

Discipline thesis:degree_discipline

Geophysics

Grantor

University of Houston

Year dc:date.issued

2026

Author dc:creator

• Thomson, Jack Kean 2001-

Advisor dc:contributor.advisor

• Wang, Guoquan

Committee members dc:contributor.committeemember

• Sun, Jiajia
• Deng Fanghui

• Subsidence
• Urban fault movement

Language dc:language.iso

English

Handle dc:identifier.uri

https://hdl.handle.net/10657/21606

OAI identifier oai:identifier

oai:uh-ir.tdl.org:10657/21606