CO₂ flux from Javanese mud volcanism

Area of Science:

• Geochemistry
• Geology
• Earth Science

Background:

• Understanding CO2 emissions from back-arc mud volcanoes is crucial for modeling geological processes and the global carbon cycle.
• Mud volcanoes play a significant role in fluid dynamics, thermodynamics, and geochemistry.
• Quantifying CO2 fluxes is essential for accurate carbon cycle assessments.

Purpose of the Study:

• To measure and constrain the CO2 flux from the Bledug Kuwu mud volcano.
• To determine the origin of CO2 emitted by the mud volcano.
• To assess the contribution of Javanese mud volcanism to the global carbon cycle.

Main Methods:

• Scanning remote sensing absorption spectroscopy was employed to measure CO2 fluxes.
• Geochemical, geological, and geophysical evidence were analyzed to infer CO2 sources.
• Man-portable active remote sensing instruments were utilized for gas release probing.

Main Results:

• The Bledug Kuwu mud volcano expels gas rich in CO2 (≥16% volume fraction).
• A lower limit CO2 flux of 1.4 kg s⁻¹ (117 t d⁻¹) was determined.
• Extrapolation suggests Javanese mud volcanism contributes ~3 kt d⁻¹ CO2, comparable to magmatic CO2 efflux.

Conclusions:

• The CO2 source at Bledug Kuwu is a likely mixture of thermogenic, biogenic, and magmatic origins.
• Faulting appears to control pathways for magmatic fluid migration.
• Remote sensing offers a viable method for quantifying CO2 fluxes from natural gas releases.