Natural H2 Emanations in the Rio de la Plata Craton, First Data

Moretti, Isabelle; Prinzhofer, Alain; Roche, Vincent

doi:10.3390/geosciences16030120

Abstract

This study presents the first comprehensive soil gas survey across southern Uruguay’s H₂ prospective terranes. A pre-field trip selection was done on the basement rock nature, as well as vegetation anomalies in subcircular depressions and fault presence. The Neoproterozoic terrane, north of Punta del Este, and the Archean Rio de la Plata Craton, north of Montevideo, as well as along the suture zones between the two, were targeted. Our findings reveal substantial H₂ concentrations, significantly outperforming many established basins worldwide. The suture zones act as critical migration conduits for H₂ coming from a deeper structural level. Slightly abnormal helium signatures confirm an active, deep-sourced fluid system, particularly within the Sierra Ballena and Cordillera shear zones. The Archean Rio de la Plata Craton appears promising but has only been partially sampled and warrants further investigation. These results underscore the high potential of Uruguay as a new frontier for natural hydrogen exploration.

Keywords:

natural hydrogen; Uruguay; Rio de la Plata Craton

1. Introduction

Natural H₂ exploration is currently active in various parts of the world [1,2,3] in the hope of reducing the carbon footprint of human activities as H₂ is a naturally carbon-free fuel. Cratons, both Archean and Neoproterozoic, have been shown to contain numerous H₂-rich areas [4]. These have been identified in Mali [5], in Russia [6], in Namibia [7,8], in Australia [9] and in Brazil [10,11], among others. The H₂ could be generated either by radiolysis [12,13] or by oxidation of the Fe-rich facies, such as Banded Iron Formation (BIF) [14], biotites in the granites [15] or greenstone belts [16]. In Uruguay, the Rio de la Plata Craton faces the Kalahari Craton in Namibia, where H₂ has already been confirmed (Figure 1). It is, therefore, worthwhile to study the area. Potential H₂-generating rocks have been mapped by [17], but no data has yet been published about the presence of natural H₂ in the subsurface. Here, we present a set of new data on soil gas and some laboratory measurements that confirm the high potential of the country, at least of the southern central part, where the data have been collected. Measured helium anomalies confirm deep fluid transport to the surface.

Figure 1. Cratons of South America, their relationship with the African ones and the presence of H₂ already confirmed by well data or soil gas emanation measurements. Data from Amazonia [4], São Francisco [10,11], Rio de la Plata for the Brazilian part/Paraná Basin [18], Damara Belt, Namibia [7,8], South Africa [12], Mali [5,19], and Morocco [20].

1.1. Geological Setting of Uruguay

Under the umbrella term of the Rio de La Plata Craton, Uruguay’s geology consists of a Precambrian basement and three main sedimentary basins [21,22,23]. The basement is divided into three primary domains (Figure 2) from west to east:

Piedra Alta Terrain (PAT): A Paleoproterozoic unit featuring metamorphic belts, granite-gneiss areas, and the Florida Dyke Swarm.
Nico Pérez Terrain (NPT): A central region of Archean to Paleoproterozoic rocks reworked during the Brazilian-Panafrican cycle.
Dom Feliciano Belt (DFB): An eastern belt formed during the Brazilian-Panafrican cycle (750–550 Ma), containing supracrustal rocks and granitic intrusions [24].

And there are three principal onshore basins:

Norte Basin (NB₁ to NB₃, Figure 2): The Uruguayan portion of the Paraná Basin. It contains Paleozoic to Mesozoic sedimentary rocks and thick basalt flows (up to 1000 m). Its infill spans four mega-sequences: Devonian marine, Carboniferous-Permian glacial/fluvial, Jurassic-Cretaceous volcanic/continental, and Upper Cretaceous fluvial deposits [25].
Santa Lucía Basin (SLB): A southern pull-apart basin featuring Mesozoic continental deposits and basaltic flows.
Laguna Merín Basin (LMB): An eastern basin characterized by Jurassic-Cretaceous igneous rocks and a Cenozoic sedimentary cover [26].

Figure 2. (a) Major geological provinces of Uruguay, modified from [27], (b) presence of H₂_GR in Uruguay modified from [17]. H₂_GR1: mafic and ultramafic rocks, H₂_GR2: iron rich sedimentary or intrusive rocks, H₂_GR3 radioactive facies, H₂_GR4 organic rich rocks [28].

As stated before, Uruguay is surrounded by countries where natural H₂ has already been mentioned. Northward in Brazil, wells with up to 8% of H₂ have been reported in the Paraná Basin, mainly in the Paleozoic sediments [18]. The authors proposed, therefore, the coal of this basin as the source, but they do not disregard a deeper origin. Eastward, in Namibia, on the other side of the Atlantic Ocean, many vegetation anomalies (Sub Circular Depression, SCD) are associated with active flow of H₂ in the soil [7,8]. In contrast to Brazil, the source of H₂ appears to be different, and the authors favor H₂ generation related to the alteration of Banded Iron Formation (BIF). Taking all these positive factors into account, it therefore seems reasonable to ask about the potential of Uruguay to contain natural H₂.

1.2. Natural H₂ Generation

H₂ is generated in the subsurface mainly by the water-rock interaction (oxidoreduction reactions or radiolysis) or by the late maturation of organically rich rock [28]. These three main reactions and four main contexts were named from H₂_GR1 to H₂_GR4 by the previous authors and we will use this wording, which was also adopted by [17] who mapped them in Uruguay (Figure 2b). The water reduction is expected to be very active in presence of mafic and ultramafic rocks (reaction of serpentinization) or in the case of iron-rich sedimentary rock, such as BIFs [8,14] or siderite [29]. The BIFs, which may contain more than 50% of iron, are Archean or Neoproterozoic in age, and even if they are partially oxidized, they may still contain a large quantity of Fe²⁺. Iron formations are common in the South American platform and have been described in Brazil (especially in the São Francisco Craton) but also in Uruguay [30]. Radiolysis also generates H₂ in the presence of H₂O [31], and the late maturation of organic matter (above 250 °C [32,33]) constitute the last main processes. Other reactions may generate H₂, such as the H₂S oxidation [34], but it is mainly important for the volcanic area. In Uruguay, all four H₂_GR are potentially present.

Serpentinization is fast at high temperature (around 300 °C, [35]) but clearly also at low temperature since H₂ is observed in many ophiolitic nappes which are not so currently buried [36]. The optimum temperature rate for the H₂_GR2 is lower, may be as low as 100 °C [14,37]. The radiolysis is not temperature dependent, and, as mentioned before, the late maturation of organic matter requires high temperature and is very unlikely in the first 6 km.

1.3. Natural H₂ Transport, Accumulation and Dysmigration

Once generated, H₂ will move through the subsurface, like all fluids, either as a free gas phase or dissolved within the formation waters, facilitated by its enhanced solubility under high-pressure, deep-subsurface conditions [38]. The H₂ transport mode could be diffusive or advective but quantitative modeling indicates that the diffusion is virtually negligible, because it is too slow, at basin scale [39]. Carrier beds and aquifers serve as primary conduits facilitating long-distance H₂ transport far from its generation zone [39,40]. Finally, the H₂ may remain trapped as free gas in the reservoir below a seal, as in Mali [5,41], or be largely dissolved in aquifers but also reach the surface. Since H₂ solubility decreases when depth decreases, exsolution is expected from the shallow aquifers, resulting in H₂ emanations [39]. Additionally, reservoirs may not be perfectly sealed and may leak [42]. Features related to these emanations were first described in Russia [43] and in the US [44] and are now used daily as a proxy to de-risk H₂ exploration. However, the presence of SCD is neither necessary nor sufficient to ensure the presence of an accumulation. These H₂ escapes often affect the vegetation, which may disappear, as in the Minas Gerais in Brazil [10], or just be less developed, as in Colombia [45]. In all cases, vegetation indexes such as the NDVI (Normalized Difference Vegetation Index) or the SAVI (Soil Adjusted Vegetation Index) allow for the visualization of these anomalies [7].

Fault systems typically channel fluid migration, including water, hydrocarbons and other gases [46]. When the rocks are tight, bulk porosity and permeability may be very low, making fracture-related secondary permeability dominant. Consequently, the role of faults is predominant in tight-matrix, but in all cases, they play a role in the migration pathway. It has been observed regardless of the stress regime but is more pronounced when the faults are active [47]. Higher H₂ contents have been observed in fault zones compared to values in the soils at larger distances from the structural discontinuities in compressive zones, such as the Pyrenean foreland [48] or the Dinarides [49], in extensional margin, such as the Perth Basin in Australia [50], or the Atlantic margin in Brazil [51]. In fault zones, the H₂ signal often appears to be more constant and not subject to daily fluctuation, as observed in the soils [10,52]. In the Uruguayan craton, the rocks are rather tight and the faults are expected to play a key role in gas migration. The main ones are roughly N-S shear zones and converge toward Punta del Este (Figure 2a).

2. Methods

2.1. Selection of the a Priori Prospective Zones

In comparison to the H₂ provinces in other countries, we first wanted to test the H₂ presence in:

The lithospheric shear zones (hypothesis: H₂ generated in deep levels and migrating through the fault zone).
The Neoproterozoic terranes and the Archean craton (hypothesis H₂_GR2 or H₂_GR3), as in Namibia.
The area where coal seam could be present (hypothesis H₂_GR4 as in the Parana Basin in south Brazil).

The remote sensing approach developed before the field trip allowed us to highlight the presence of many SCDs that were then targeted during the field acquisition. These SCDs were often aligned with the suture zones visible in Figure 3.

Figure 3. Samples of SCDs that were mapped before the mission and gas measurements were taken on them. (a) Infrared vegetation index highlighting an SCD in the Rio de La Plata area, (b) satellite (GoogleEarth Pro) images showing (b1,b2) aligned SCDs between the two shear zones of Sarandi del Yi and Sierra Ballena and (b3) zoom on a typical Uruguayan CSD, rather small and full of water.

2.2. Field Acquisition and Laboratory Gas Analyses

The soil gas measurements were acquired with a GA5000. The version we used for this field trip analyses the soil-gas content in CO₂, CH₄, O₂ in % (accuracy ±0.5% vol) and H₂ in ppm (accuracy ±2.5% FS), a balance is computed, which usually corresponds to the N₂. After digging a small hole in the ground, or in the rock depending on what is exposed, approximately 100 cm long and 15 mm in diameter, a tube is installed in the soil to collect the gas at that depth. Details on the protocol can be found in [28]. There is a wealth of literature on the best way to make this hole (rotation or not), the best season (dry or wet) [53], and the best time of day (before rain, during rain, midday) [7,52] to obtain the most representative measurement. But overall, everyone who takes this type of measurement recognizes that the signal varies over time and space and that it is the overall picture and geographical distribution of H₂ anomalies, rather than any particular value, that is significant [28].

When the depth of penetration of the drill bit, and there of the tube, is lower, that could be the case when hard rocks are outcropping, it is indicated in the last column of the result table (Appendix A Table A1). Systematic deepest measurements, down to 7 m, have been done once, in Colombia [54], and results show that the gradient of H₂ content versus depth is sometimes positive, sometimes negative. Even though there is greater dilution with air in the first few centimeters of soil, the standard depth of between 50 and 100 cm seems sufficient to verify that there is a deep signal. When we are above an H₂ emanation zone, the pulses of H₂ in the soil, similarly to gas bubbles rising in a water saturated zone, are random, as are their frequency and intensity. Only by staying in an area for a long time and taking many measurements can we be sure of its activity. In general, we took about ten measurements at each studied zone.

Microorganism activity can also influence the H₂ content in the soils. In general, this influence is negative, as microorganisms consume H₂ [55], but fermentation can also generate it [56]. These influences are generally considered to be of secondary importance, and statistical approaches can be developed to separate near-surface noise from deep flow [48]. These last authors find a threshold at 74 ppm in their case study (the foreland of the Pyrenees) but this value is not universal. GA5000 is very sensitive (1 ppm), and legitimate doubts may arise if the signal is weak (e.g., less than a few tens of ppm) and inconsistent with the geology.

Due to the internal pump in the GA5000, the small volume of gas around the tube is pumped during the 2 min of the measurement; it is classically replaced by air, and gas contents, other than O₂ and N₂, decrease, except when there is an active flow of deep gases. To test the existence of this deep flow, one may do monitoring and repeat the measurements; this has been done, for instance, in Brazil with one measurement each hour during months [10,52], but for a first acquisition campaign, we did not choose this rather heavy option. Due to time constraints, we only left the tube in place and closed it for a couple of minutes and measured the gas content afterwards. Any H₂ content during the second or third measurement confirms H₂ upward displacement and therefore some flow. As a matter of fact, in many SCDs, after an initial H₂ peak measured with the GA5000, no measurable recharge is observed in the following hours of the day. However, sometimes, a recharge may be observed during several minutes or hours, indicating that hydrogen is actively seeping during the entire series of measurements [51]. It constitutes a proof of an active H₂ system.

Another option to ensure that some active flow exists is the helium measurement. This will be discussed later.

At a few locations, samples of the soil gas have been taken with vial. They have been analyzed in a laboratory in France with a μGC and also allow the He and Ne content to be determined.

Classically, the measurements published using a GA5000 (or other similar tools) are the maximum of the H₂ signal, which is reached after a few tens of seconds due to the velocity of the sensor but also due to the diffusion rate of the H₂ toward the tube.

During the field campaign, 155 soil gas measurements were done (raw data in Appendix A) and 11 gas samples were collected.

3. Results

3.1. Soil Gas Measurements

All the measurements are in Appendix A. The statistics are presented in Figure 4 and the values in the map in Figure 5.

Figure 4. Statistical distribution of H₂ soil content; raw data in Appendix A.

Figure 5. Location of the soil gas measurements. The size of the circles highlights the H₂ content. The GA5000 threshold, 1000 ppm, was exceeded at three locations.

We first have to note that the values were high, with a mean value of around 140 ppm and roughly two-thirds of the measurements being above 50 ppm.

As expected, the fault zones are preferential migration pathways, and the highest values (saturation of the GA5000, large red circle, Figure 5) were above the faults.

3.2. Gas Geochemistry

Among the 155 measurements performed in the southeastern part of Uruguay, 11 gas samples were taken whose H₂ concentrations were high, and a complete gas chromatographic measurement was made to measure precisely the concentrations of helium, neon, hydrogen, oxygen, nitrogen, methane and CO₂ (Table 1).

Table 1. Gas chromatography analyses and comparison with field measurements for the H₂ (last column). The helium and hydrogen uncertainties are ±0.2 ppm. The other gases present uncertainties of 0.03%.

Two spots (PN 88 and PN 95) saturated the H₂ detector GA5000 with concentrations above 1000 ppm. Six have shown concentrations above 500 ppm, and 73 samples had concentrations above 100 ppm. The maximum concentrations of methane and CO₂ were 0.7% and 9.3%, respectively, and are probably related to superficial biological methanogenesis and soil respiration, respectively.

4. Discussion

4.1. Presence of H₂ in the Uruguayan Subsurface

4.1.1. Suture Zones

Measurements done on the Sierra Ballena (SBSZ) and Cordillera (CSZ) shear zones are uniformly high (Figure 6) and these fault zones appear to be drainage features for H₂. The granite belt between the two shear zones is Neoproterozoic (Cryogenian) and displays very high values.

Figure 6. Example of measurements across the SBSZ. The numbers indicate the H₂ content in ppm at the location, and the color from white to red indicates the variation in this content. The highest H₂ content is found on the fault (almost vertical). The width of the highly deformed zone is indicated by the double arrow, and the main slip plane by the dotted line. The zone has been crossed twice and the H₂ content displays the same pattern. Measurements from points 98 to 103 in the table.

Westward in the Sarandi del Yi Shear Zone, values are lower in the south (Piriapolis area) but happen to be very high northward (contact Rio de la Plata Craton). More systematic data collection along this lineament should be done to conclude about its potential.

4.1.2. Regarding the Pre-Selected Sub-Circular Depression

The SCD we had scouted had promising features (as the one in Figure 7), but we learned that all properties had to have a natural pond if they housed livestock. This raises the question of the origin, natural or otherwise, of these depressions. The soil gas measurements confirmed that they correspond, in the vast majority, to areas of H₂ emanations but are deepened by earthwork to create water reserves. Their alignment with the direction of the faults leads us also to believe that the depressions existed before the farmers’ work.

Figure 7. Measurements in one of the SCD (measurements number from 75 to 83 in the Appendix A, values H₂ content in ppm), the apparent diameter of the area with water is about 100 m, but the depressed area is much larger. This example is representative of the SCD, where we measured H₂. Earthworks had been carried out to create a water reserve (essential for the animals), taking advantage of an initial natural depression, probably due to gas escapes.

4.1.3. Archean Craton

Due to time constraints and heavy rains, only the southern part of the Rio de la Plata craton has been reached (points 40 to 61 in the Appendix A), north of Montevideo. Values were high, up to 556 ppm. We performed a recharge test (point 57): the initial value was 349 ppm. It dropped to close to 0 at the end of the two-minute measurement, but after 6 min it roses again up to 83 ppm and after half an hour to 198 ppm. This rapid recharge shows that H₂ flow is active in the area.

4.2. Relation Between the Various Deep Gases

Comparing the H₂ concentrations measured directly in the field and from laboratory measurements with a gas chromatograph (Table 1), it appears that the H₂ concentrations observed in gas samples are systematically lower than the ones measured in the field. The fit is never perfect but such a gap is unusual. This may be explained by the fact that the field measurements with the GA5000 detector use an electrochemical sensor, which induces a time shift between the observed H₂ peak and the real H₂ presence in the tubing. This induces a difficulty in sampling the gas exactly during the real H₂ maximum, different in time from the observed maximum with the GA5000. With a GA5000, the maximum is usually reached between 35 and 45 s, but the peak of the H₂ is reached before and the sampling in the vial takes a few seconds. Therefore, in the vial, one samples a non-constant gas during an interval that rarely corresponds to the maximum of H₂. As a result, the H₂ content measured by both methods is never the same; GCs are usually smaller, and the field data is more accurate at measuring the maximum but both indicate similar trends [43].

However, very important information may be observed with the laboratory analyses: the helium concentration of the air is 5.24 ppm. Any excess in the helium concentration indicates that a gas flow from the subsurface is active during the measurement. The helium measurements presented in Table 1 have an uncertainty of ±0.2 ppm. As a matter of fact, helium cannot be generated by any superficial process, biological or chemical, and cannot be adsorbed, and then desorbed, on the mineral surface, contrary to H₂, which may be adsorbed on shale minerals, and may be generated either through biological generation or human artifact during the drilling [53]. No positive helium anomaly is observed except in the gases PN 82, PN 94 and PN 95. Even if some uranium and thorium may exist in low concentrations in soils, associated helium generation through natural radioactivity needs geological times in order to generate measurable helium amounts. A soil may be considered as an open system through geological times, indicating that absolutely no helium anomaly may be associated with soil production, but needs to migrate from the subsurface.

This direct proof of a deep flow of helium, and probably associated H₂, may be confirmed for the other gas samples, even if the helium concentrations are only slightly but significantly above the air concentration (Figure 8a).

Figure 8. (a) Correlation between the helium and hydrogen concentrations obtained with a gas chromatograph; (b) correlation between nitrogen and oxygen concentrations obtained with a gas chromatograph. The uncertainties are those presented in the Table 1 caption.

Comparing the nitrogen and oxygen concentrations (Figure 8b), an inverse correlation occurs only due to the 100% normalization of a gas analysis, and that N₂ and O₂ are the two main gas compounds. The decrease in O₂ concentration is due to soil respiration, whereas the associated N₂ increase may be either due to a simple normalization effect, or to an addition of deep N₂. The fact that the neon concentrations remain constant and close to air values favors the second interpretation for the N₂ concentrations

Figure 9 presents the relation between nitrogen and hydrogen concentrations and between nitrogen and helium concentrations. It is confirmed that the samples PN82, PN94 and PN95 do not present any helium anomalies. However, these three gases present relatively high hydrogen concentrations, maybe linked to superficial biological generation. As is usually observed, a rough correlation may be observed between helium and nitrogen, whereas the correlation is not clear between hydrogen and nitrogen. The usual interpretation of a correlation between helium and nitrogen is the area where both gases are generated, i.e., the metamorphic terrains at depth. Their generation is quite different, as helium is generated through the natural radioactive decay of uranium and thorium, whereas nitrogen is generated through the decomposition of ammonium ions and organic matter at great thermal stress.

Figure 9. Correlation between nitrogen and helium (a) and hydrogen (b). The uncertainties are those presented in the Table 1 caption.

On a map of the studied area (Figure 10), we may define three areas with a confirmed hydrogen potential (red areas) because they are associated with small helium anomalies. The area north of the map (samples PN 94 and 95) does not show this evidence of helium. It could be interpreted in terms of the absence of deep gas flow in the two samples analyzed or another H₂ generation process.

Figure 10. Map of the studied area, with the red areas presenting the highest interest for hydrogen exploration. In the yellow area, the H₂ content is high but there is no He, which may be due to a lack of deep flow or to another H₂ generation process.

In conclusion, the gas analyses show that, apart from the H₂ evidence in various spots of the studied area, adding the helium measurements allows us to distinguish areas affected by active deep gas flow from areas where the presence of H₂ may be either due to gas desorption during our drilling operations or to artificial hydrogen generated during the drilling. Three sweet spots could be defined, as presented in Figure 10.

5. Conclusions

The Sierra Ballena and Cordillera shear zones act as leakage features for both H₂ and helium; therefore, a review of potential aquifers, reservoirs and seals in the vicinity should be conducted. These zones also have the advantage of being close to the coast and to potential customers or export hubs should reserves be identified. The SBSZ extends northward into Brazil within the same geological context and warrants further attention.

The Sarandi del Yi Shear Zone exhibits lower H₂ leakage in the south and does not contain helium anomalies in the north of the studied area. It may be considered as a second priority, but considering only a few data (Figure 4), additional measurements may be useful before drawing definitive conclusions, particularly as northern faults were reactivated during the Cenozoic [57].

The Archean craton looks promising and deserves more time for data acquisition. More generally, as only a small portion of Uruguay was covered through this first field trip, northward the presence of H₂ also has to be tested. The reactivation of faults in this region, studied using high-resolution topographic data, has recently shown that this region is less stable than previously assumed [57]. This reactivation of ancient structures is confirmed by current seismicity [58] and may represent a highly favorable factor for the circulation of deep-sourced fluids, as confirmed here by the helium anomalies. In conclusion, the presence and concentration of H₂ are very encouraging and strongly justify continued acquisitions to better understand the H₂ and helium systems within the country.

Author Contributions

The three authors contributed equally: I.M., A.P. and V.R. participated in the field work, analyzed the data, and wrote, reviewed and edited the manuscript. All authors have read and agreed to the published version of the manuscript.

Funding

This research was also supported by the Pulsar Programme of Région Pays de la Loire.

Data Availability Statement

The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

Acknowledgments

We would like to express our warmest thanks to Ricardo Bertolotti and Juan Negro, who became passionate about natural H₂ in the Southern Cone of South America, created Nativo, and made this work possible. We also benefited in the field from the presence and knowledge of Marcos Sequeira Callazo and Facundo Plenc, both students at the University of La Republica at Montevideo.

Conflicts of Interest

Author Isabelle Moretti was employed by the company MI-Energie. Author Alain Prinzhofer was employed by the company GEO4U. The authors declare that the research was conducted independently and that their affiliations did not influence the scientific outcomes of the study.

Appendix A

Field data. Data measured with a GA5000. CH₄, CO₂ and O₂ in %, H₂ in ppm, depth in cm. When depth is not specified, it is between 80 and 100 cm.

Table A1. Identifier of the sample, coordinate and gas content of the soil gas; the remaining part is roughly the N₂.

id	X	Y	CH₄	CO₂	O₂	H₂	Depth
1	−34.883402	−55.230623	0.6	0.1	20.4	171
2	−34.883402	−55.230623	0.6	0.1	19.9	138	50
3	−34.883292	−55.230818	0.5	0.2	19.8	44
4	−34.883113	−55.231111	0.5	0.1	19.8	53	30
5	−34.883006	−55.231356	0.5	0.1	19.6	2	30
5bis	−34.882997	−55.231713	0.5	0.1	19.4	205	50
6	−34.883235	−55.231856	0.5	0.1	19.6	12	60
7	−34.882294	−55.230130	0.4	0.6	19.4	16	80
8	−34.882308	−55.229968	0.5	0.6	19.7	0	80
9	−34.882401	−55.229720	0.4	0.7	19.7	0	70
10	−34.881688	−55.229341	0.4	0.2	20.1	5	60
11	−34.881453	−55.229367	0.4	0.6	19.9	14	90
12	−34.879710	−55.228012	0.4	0.1	20.3	12	80
13	−34.879623	−55.228227	0.4	0.3	20.1	0
14	−34.883602	−55.230976	0.4	1.1	19.7	4	80
15	−34.883838	−55.230960	0.4	0.1	20.9	9	40
15bis	−34.883838	−55.230960	0.4	0.1	20.5	26	30
15ter	−34.883838	−55.230960	0.3	0.1	20.5	34	40
16	−34.540322	−55.311296	0.5	0.2	19.4	39	90
16bis	−34.540244	−55.311292	0.4	0.2	19.2	31
17	−34.540123	−55.311118	0.4	0.2	20.4	35	70
18	−34.539786	−55.312567	0.4	0.3	20	22
19	−34.539288	−55.312625	0.4	0.3	20	100	40
20	−34.538700	−55.312858	0.4	1.3	18.9	0	100
21	−34.538196	−55.312680	0.3	0.2	19.5	22
22	−34.537719	−55.312316	0.3	0.2	20.1	6	100
23	−34.540253	−55.312344	0.3		19.4	144	100
24	−34.540452	−55.312395	0.3	1.3	19.4	29	100
25	−34.507954	−55.372205	0.4	0.1	20.4	62	50
25bis	−34.507954	−55.372205	0.3	0.1	20.6	11
26	−34.508300	−55.376193	0.3	0.1	20.7	5	50
27	−34.508480	−55.376320	0.3	0.1	20.6	13	100
28	−34.508756	−55.376670	0.3	1.5	19.1	21	40
29	−34.512441	−55.374390	0.3	0.3	20.8	36
30	−34.512793	−55.374477	0.3	0.1	21	0
31	−34.488147	−55.364545	0.2	0.7	19.9	73	100
32	−34.488373	−55.364485	0.2	0.5	20.9	99
33	−34.488478	−55.364246	0.2		21.1	0	100
34			0.2	0.4	19.5	18
35	−34.488309	−55.364780	0.2	0.2	20.7	110	100
36	−34.488116	−55.365125	0.2	0.7	20.4	71
37	−34.488276	−55.365551	0.2	0.5	20.7	31
38	−34.488555	−55.365552	0.1	0.5	20.8	80
39	−34.488507	−55.364856	0.1	0.4	20.8	77	80
40	−34.432614	−56.263566	0.5	0.4	20.8	100	100
41	−34.432326	−56.263691	0.4	0.1	20.4	62
42	−34.432795	−56.263216	0.4	0.4	20	84
43	−34.432901	−56.262526	0.4	0.2	20.1	94
44	−34.433031	−56.261045	0.3	0.4	20	170
45	−34.433469	−56.260741	0.3	0.3	19.9	28	100
46	−34.321534	−56.245632	0.4	4.8	19	104
47	−34.321145	−56.245777	0.3	8.9	17.2	243	100
48	−34.320486	−56.245791	0.2	0.4	19.7	556
49			0.3	0.3	20.6	364	100
50	−34.320403	−56.245413	0.3	0.4	20.5	90
51	−34.320203	−56.245382	0.2	0.3	20.7	255	80
52	−34.319646	−56.245433	0.2	1.3	18.6	71
53	−34.319445	−56.245555	0.2	0.6	19.9	112
54	−34.319004	−56.245924	0.2	0.2	20.8	239	100
55	−34.319402	−56.246367	0.2	0.4	20.7	92	100
56	−34.320438	−56.246011	0.2	0.1	16.1	120	60
57	−34.320580	−56.245652	0.2	0.2	21	349	70
57 reload_1	−34.320580	−56.245652				70
57 reload_2	−34.320580	−56.245652				83
57 reload_3	−34.320580	−56.245652				198
58	−34.317666	−56.251127	0.2	0.2	21.4	39
59	−34.317318	−56.250712	0.2	0.3	21.2	75	75
60	−34.090220	−56.573650	0.3	0.6	21	8
61	−34.090225	−56.573658				0
62	−34.791536	−54.853242	0.5	0.2	20.7	65	15
63	−34.791469	−54.852859	0.5	1	20	3	70
64	−34.791502	−54.852761	0.5	0.6	19.8	30	40
65	−34.791776	−54.852580	0.5	0.6	19	14	60
66	−34.792113	−54.852431	0.5	0.7	19.4	183	100
67	−34.792420	−54.852701	0.4	0.1	19.5	160	80
68	−34.792552	−54.852473	0.4	0.3	19.5	20
69	−34.792783	−54.852066	0.4	0.1	19.4	93	100
70	−34.793027	−54.852262	0.4	0.1	18.9	110	80
71	−34.793019	−54.852818	0.3	0.1	19.4	139	80
72	−34.792472	−54.853121	0.3	0.2	19.6	40	75
73	−34.792019	−54.853469	0.3	0.1	19.9	266	90
74	−34.791689	−54.853396	0.3	0.1	20	74	80
75	−34.718429	−54.989311	0.4	6.2	16.9	315	95
75bis	−34.718429	−54.989311				41
75ter	−34.718429	−54.989311				38
75-IV	−34.718429	−54.989311	0.3	0.2	16.8	21
76	−34.718377	−54.988940	0.3	1.9	19.6	144	80
77	−34.717930	−54.988929	0.3	2.1	19.4	215	80
78	−34.717699	−54.989046	0.3	0.1	20.8	192	85
79	−34.718026	−54.989483	0.3	0.3	20.8	159
80	−34.712171	−54.983403	0.3	1.1	20.2	204
81	−34.712246	−54.983220	0.3	0.9	19.7	100	35
82	−34.712424	−54.983394	0.3	0.3	21	841	50
82bis						150
83	−34.711767	−54.984557	0.3	0.4	21	18	20
83bis			0.2	0.1	21.1	98
84	−34.711751	−54.984518	0.2	0.7	21	81	100
85	−34.636413	−54.966847	0.3	0.5	20.8	36	20
85bis			0.3	0.5	20.7	199	40
86	−34.636413	−54.967086	0.3	0.1	20.9	86	40
87	−34.637761	−54.966847	0.3	0.9	20	38	20
88	−34.638598	−54.960433	0.3	1.3	20.1	1500	40
89	−34.639168	−54.959258	0.3	0.2	21.2	30
90	−34.640436	−54.955973	0.3	0.5	21	430	30
91			0	0.4	20.4	27
92			0.5	0.1	20.5	108	20
92bis			0.5	0.4	20.3	64	70
93	−33.066960	−55.472813	0.6	0.1	21	518	40
94	−33.066976	−55.472895	0.5	0.1	20.8	360	70
95	−33.067085	−55.472622	0.5	0.1	20.8	1500	45
95bis						464
96	−33.047511	−55.494179	0.4	0.1	20.6	499	50
96bis			0.4	0.1	20.8	295	70
96ter			0.4	0.1	21	194	80
97	−33.195834	−55.501510	0.5	3.9	17.2	193	50
98	−33.195971	−55.501404	0.4	0.6	20.7	61	70
99	−33.195980	−55.501383	0.5	1.5	19.8	138	80
100	−34.656656	−54.525841	0.6	0.3	20.4	27	100
101	−34.656690	−54.525870	0.6	0.1	20.7	158	100
102	−34.656492	−54.526102	0.6	0.1	20.9	6	10
103	−34.656037	−54.526191	0.5	0.1	20.6	76	40
104	−34.655736	−54.526626	0.5	0.1	20.6	153	25
105	−34.441526	−54.369726	0.6	0.4	20.6	100	100
106	−34.441192	−54.369384	0.5	0.2	21	16	90
107	−34.440655	−54.369435	0.5	0.1	20.7	277	80
108	−34.440958	−54.369670	0.5	0.5	20.6	94	75
109	−34.426688	−54.391894	0.5	0.2	20.8	0	20
110	−34.426560	−54.391844	0.5	1.6	21	0	90
111	−34.425863	−54.391691	0.5	0.1	199	195	70
112	−34.425740	−54.391008	0.5	0.5	20.5	20	80
113	−34.408849	−54.425014	0.5	0.7	20.6	85	85
114	−34.408943	−54.425017	0.4	0.1	20.8	6	75
115	−34.409891	−54.423382	0.4	0.5	20.2	52	100
116	−34.410346	−54.421553	0.4	0.1	20.9	28	20
117	−34.410482	−54.420871	0.4	0.1	20.1	0
118	−34.330588	−54.404794	0.4	4.3	19.9	78	30
119	−34.330623	−54.404534	0.4	7.3	15.3	153	90
120	−34.330815	−54.404317	0.4	0.4	20.7	29
121	−34.308529	−54.415008	0.5	0.3	20.9	21
122	−34.308581	−54.415121	0.4	0.9	20.5	243	90
123	−34.308658	−54.415179	0.4	0.6	20.6	29	20
123bis			0.4	1.2	20.2	170	60
124	−34.561556	−54.924488	0.7	0.8	19.2	285	75
125	−34.561139	−54.924806	0.5	7.2	12.2	107	100
126	−34.561111	−54.925000	0.5	0.8	19.2	225	70
126bis			0.5	2.4	17.1	101	25
127	−34.561111	−54.925528	0.5	0.1	19.7	95	45
128	−34.560917	−54.925833	0.4	0.4	19.3	37	30
129	−34.560861	−54.925889	0.4	7.4	10.6	24
130	−34.561224	−54.924407	0.3	1.4	17.8	45	90
131	−34.561631	−54.923044	0.3	0.6	18.4	177	25
132	−34.561781	−54.922626	0.3	0.3	18.8	94	25
133	−34.561943	−54.922692	0.3	9.3	11.4	75	90
134	−34.561961	−54.922764	0.3	0.1	20.1	16	15
135	−34.562428	−54.922141	0.3	2.2	15.6	450	75
136	−34.302653	−54.836454	0.5	0.3	20.4	219	40
137	−34.302441	−54.836779	0.5	0.1	20.6	124	30
138	−34.302404	−54.836618	0.4	6.7	12	71	80
139	−34.302146	−54.837392	0.4	0.9	19.5	232	50
140	−34.302122	−54.837431	0.4	2.6	17.1	319	90
141	−34.302094	−54.837707	0.4	0.7	20.1	316	80
142	−34.301985	−54.83791	0.4	0.4	20.6	456	90
143	−34.301084	−54.838479	0.3	0.4	18.7	199	90
144	−34.598877	−54.763074	0.4	0.5	20.3	131	40
145	−34.598848	−54.763239	0.4	1.6	19.7	29	70
146	−34.599068	−54.762629	0.4	0.1	20	450
147	−34.599334	−54.76231	0.3	0.3	19.8	215
148	−34.599619	−54.761867	0.3	0.2	20.4	752	80
149	−34.599715	−54.7618	0.3	0.7	20.1	292	80
150	−34.500047	−54.761798	0.3	0.5	19.8	97	90
151	−34.560288	−54.772257	0.4	1.5	18.6	245	45
152	−34.560332	−54.772133	0.3	2.3	17.3	94	60
153	−34.560197	−54.771903	0.3	6	14.5	93	100
154	−34.559992	−54.772832	0.3	0.3	20.4	295	25
155	−34.559999	−54.772926	0.3	3.9	15.4	78	75

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