50+ Earth & Marine Sciences Dissertation Topics for 2025

If you’re stepping into the world of Earth and Marine Sciences, your dissertation isn’t just another assignment — it’s your chance to explore real-world questions that matter. Whether you’re curious about changing coastlines, deep-sea ecosystems, or human impact on natural systems, the right topic can help you dive into meaningful research with confidence.

To help you get started, here’s a collection of fresh and research-worthy Earth and Marine Sciences dissertation topics for 2025 — not generic, not overused, and definitely not boring.

Earth & Marine Sciences Dissertation Topics

• Impact of coastal urban development on marine biodiversity
• Microplastic distribution in deep-sea sediment layers
• Ocean acidification trends in polar marine ecosystems
• Changes in ocean currents and their climatic effects
• Role of satellite data in earthquake-prone zone monitoring
• Submarine groundwater discharge and coastal salinity balance
• Historical tsunami evidence through sediment core analysis
• Marine ecosystem damage due to offshore oil drilling
• Coral bleaching comparison between protected and unprotected areas
• Sediment displacement after undersea volcanic eruptions
• Deep-sea mining and marine habitat disruption
• Soil erosion mapping after monsoon floods
• Impact of glacier retreat on alpine river systems
• Salinity pattern shifts in global oceans post-2000
• Seasonal hypoxia formation in temperate coastal waters
• Rebuilding marine ecosystems after major oil spills
• Carbon capture efficiency of coastal salt marshes
• Seismic-triggered underwater landslides and coastal change
• Use of underwater acoustics for marine mammal tracking
• Behavioural shifts in fish due to increased ocean noise
• Sediment transport disruption in dam-affected river deltas
• Role of phytoplankton blooms in oxygen depletion events
• Coral growth variation across temperature gradients
• River water quality post-glacier melt in mountainous regions
• Role of mangroves in protecting coastal land from erosion
• Natural vs. artificial reef impact on local biodiversity

• Deep-sea vent ecosystems and their species diversity
• Ocean warming impact on fish migration routes
• Subduction zone influence on deep-sea topography
• Influence of marine sand mining on coastal shape
• Sea level rise impact on low-lying island geology
• Ocean thermal expansion and global sea level models
• Human impact on estuarine sediment composition
• Freshwater input from melting ice sheets into oceans
• Comparison of sonar and satellite tech in seabed mapping
• Geochemical changes in ocean water near hydrothermal vents
• Coral reef resilience strategies in the Indian Ocean
• Marine species response to El Niño and La Niña cycles
• Subsurface temperature trends in Arctic Ocean basins
• Tectonic plate movement and mid-ocean ridge formation
• Mapping seafloor habitats using remote sensing tools
• Nutrient runoff from agriculture and marine algal blooms
• Seafloor spreading and mineral formation processes
• Earthquake prediction models using ocean-based sensors
• Methane release from undersea permafrost zones
• Crustal deformation analysis in marine trench regions
• Impact of desalination plants on marine microfauna
• Ocean circulation shifts and their impact on fisheries
• Role of isostasy in coastal uplift and subsidence
• Long-term climate records from marine sediment layers
• Monitoring marine pollution using drone-based tech
• Eco-toxicological impact of shipwreck corrosion on seabeds
• Sediment budget estimation in rapidly eroding coastlines
• Earth’s magnetic field changes recorded in oceanic crust

Final Note

If one of these topics caught your eye — good. These aren’t recycled or overly general ideas. They’re built to help you stand out, explore something meaningful, and actually enjoy the research process. Pick a topic that not only fits your interest but also has real-world application. That’s where the value is.

If you want help shaping your chosen topic into a full research question — or building a proposal around it — you’re not alone. Just start, and the rest will follow.