High-resolution monitoring of Yok Balum Cave, Belize: An investigation of seasonal ventilation regimes and the atmospheric and drip-flow response to a local earthquake

Abstract

The nature of cave ventilation is of interest to cavers, speleologists, and paleoclimatologists working with stalagmites. Because cave ventilation systematics may change over the growth span of a stalagmite, understanding what factors affect them is critical for determining events that may have affected climate proxies within the stalagmite. Similarly, understanding how the hydrology of the drips feeding a stalagmite evolves through time is key to building robust records of paleoclimate, particularly because stalagmite records have become critical archives of climate change information of the last 500,000 years. Here we present data from an extensive, on-going monitoring effort at Yok Balum Cave, Belize, initiated in 2011, that characterizes high-resolution ventilation dynamics at this site. Clear seasonal ventilation regimes exist, driven by thermally induced inside-outside air density differences. The winter regime is dominated by air inflow into the cave, decreased drawdown from the epikarst into the cave, and a limited diurnal signal. Conversely, summer ventilation is dominated by air outflow from the cave, greater CO 2 drawdown and drip water degassing, and a strong diurnal signal. Active monitoring during a large (M7.4) earthquake in November 2012 provides a unique opportunity to assess the response of the cave atmosphere and hydrology to substantial seismic activity. Cave atmosphere dynamics and hydrology are found to be highly resilient to seismic activity, with no observable disturbance occurring around the earthquake, despite there being considerable evidence of physical disruption in the cave. Monitoring included different kinds of drips, and the earthquake affected none of the monitored drip types. This suggests that stalagmite-derived paleoclimate records are not affected by seismic activity, except in extreme cases where the stalagmite or conjugate stalactite is damaged or reoriented.

Environmental parameters controlling stalagmite growth in tropical areas: New insights from cave monitoring at Petruk Cave, central Java, Indonesia

“…Seasonal fluctuation of pCO 2 -air observed in this study is typical, as in previous studies (e.g., 400 to 1400 ppm in Austria, Spötl et al, 2005; 500 to 8000 (30000 in extreme case) ppm in central Texas, Banner et al, 2007; 500 to 8000 ppm in Gibraltar, Mattey et al, 2010). Moreover, our seasonal fluctuation of pCO 2 -air is similar to that of Ridley et al (2015) although the values they observed in Belize are lower than those of this study. The summer is characterized by higher mean pCO 2 -air (̴ 500 ppm) and high temporal variability, whereas winter has lower pCO 2 -air (420 ppm) and displays lower temporal variability.…”

“…According to Spötl et al (2005), pCO 2 -air variation is driven by cave ventilation or CO 2 production in the soil zone. In the case of Belize, the change of airflow direction from inflow to outflow appear mainly due to thermally induced inside-outside air density differences (Ridley et al, 2015). However, in Petruk Cave, airflow direction is almost constant throughout the year, as shown in Figure 4, because seasonal variation of outside air temperature is much lower (Fig.…”

Reconstructing seasonality through stable isotope and trace element analysis of the Proserpine stalagmite, Han-sur-Lesse Cave, Belgium: indications for climate-driven changes during the last 400 years

“…The in phase variations of Mg, Sr and Ba in P19 described above supports the hypothesis of a seasonally changing degree of PCP. Seasonal variations in the amount of PCP and its effect on δ 13 C has previously been recognized in monsoon regions (Johnson et al, 2006;Ridley et al, 2015). During P16, seasonal changes in incongruent dolomite dissolution dominate the trace element variations of Mg versus Sr and Ba over PCP.…”

Ventilation and cave air PCO2 in the Bunker-Emst Cave System (NW Germany): implications for speleothem proxy data

“…A wide range of processes in the soil, epikarst (the uppermost zone of the karst in contact with the soil; Bakalowicz, 2012;Fairchild and Baker, 2012), and karst zone, as well as fractionation dynamics, can alter proxy data. To gain a better and quantitative understanding of the processes involved, sophisticated monitoring programs have been established (Spötl et al, 2005;Mattey et al, 2008Mattey et al, , 2010Mattey et al, , 2016Riechelmann et al, 2011Riechelmann et al, , 2017van Rampelbergh et al, 2014;Breitenbach et al, 2015;Ridley et al, 2015;Czuppon et al, 2018). In this context, a large variety of parameters have been recorded, including surface, soil, and cave air temperature, air pressure, 222 Rn, pCO 2 (carbon dioxide partial pressure) and humidity, as well as the geochemical composition of rain, soil, and dripwater.…”