the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
| 03 Jul 2024
SedDARE-IB: An open access repository of sediment data for Iberia and its continental margins
Abstract. Sediments provide valuable information for geologists and geophysicists whenever they strive to understand, and reproduce, the geological evolution, lithology, rock properties, seismic response, and geohazards of a region. The analysis of sedimentary sequences is thus useful to the interpretation of depositional environments, sea-level change, climate change, and to a recognition of the sediments' source areas, amongst other aspects. By integrating sedimentary data in geophysical modelling, such interpretations are improved in terms of their accuracy and reliability. To help our further understanding of Iberia's geological evolution, geological resources and geohazards, this work presents to the scientific community the SedDARE-IB data repository. This repository includes available data of the depth to the Base Cenozoic and Top Paleozoic stratigraphic markers for the Iberian Peninsula and surrounding Western Atlantic and Mediterranean Neogene basins, or to the acoustic basement as interpreted for the Valencia Trough and Alboran Mediterranean basins. As an example of the broad applicability of the data included in SedDARE-IB, we investigate how sediment thickness affects the depth to the 150 oC isotherm at specific basins, as commonly used in geothermal exploration. The calculated trend suggests that, given constant measured surface heat flow and thermal conductivity, the 150 oC isotherm becomes shallower as a function of sediment thickness, until a critical threshold value is reached for the latter.SedDARE-IB database has been built thanks to a Portuguese-Spanish collaboration promoting open data exchange among institutions and research groups. SedDARE-IB is freely available at https://doi.org/10.20350/digitalCSIC/16277 (Torne et al., 2024) bringing opportunities to the scientific, industrial, and educational communities for diverse applications.
- Preprint
(1626 KB) - Metadata XML
-
Supplement
(13 KB) - BibTeX
- EndNote
Status: final response (author comments only)
-
RC1: 'Comment on essd-2024-210', Anonymous Referee #1, 04 Dec 2024
The manuscript titled "SedDARE-IB: An open access repository of sediment data for Iberia and its continental margins" by Torne and co-authors, presents the SedDARE-IB database, which includes available data of the depth to the Base Cenozoic and Top Paleozoic stratigraphic markers for the Iberian Peninsula and surrounding Western Atlantic and Mediterranean Neogene basins, or to the acoustic basement as interpreted for the Valencia Trough and Alboran Mediterranean basins. Very interesting, the authors also assess the effect of sediment thickness on the depth to the 150oC isotherm (commonly used in geothermal exploration) at specific basins, as an example of the broad applicability of the data included in SedDARE-IB. The manuscript is well-written, and the sections are well structured. I collectively categorize my review as "minor revisions" and look forward to seeing the paper published at Earth System Science Data (ESSD) after some small edits – see below.
Minor Edits:
Probably an effect of the template. It would be useful for the reader to increase the size for all figures to 1.5 column or double column (full width), as well as its resolutions (see some comments below).
L80. Figure 1: Please change the label to "Tagus Basin" for clarity.
L230 Figure 3: Caption.
Please revise the sentence "Base Cenozoic marker." (see below)L324. García-Lobón et al. (2010a).
L353. García-Lobón et al. (2010b).
L353. García-Lobón et al. (2010b).
L377. Change to "the reader is referred to García-Lobón et al. (2010d)."
L384. García-Lobón et al. (2010a).
L395. Carvalho et al. (2005, 2017).
L399. (Carvalho et al., 2017).L410. "Exceptions are the Valencia Trough and the Alboran Basin, where the basement marker corresponds to the Base Cenozoic marker or the so-called Oligocene unconformity." Add this paragraph in the caption of Figure 3? See my previous comment above.
L499-504.
L501. "considering surface heat flow values ranging from 40 to 120 mW/m2": from Fernàndez et al. (1998) and IHFC (Fuchs et al., 2023)? Please add some references for the different parameters for context.The authors assume a crustal thermal conductivity of 3.1 W/m K for the crust. However, I think this value is very high. The authors could consider a thermal conductivity of 2.5 W/m K. Or it would be supportive if the authors provided a statement about the relative importance of thermal conductivity of the crust; its control over the critical threshold? Probably the main control is the own sediment thickness..
About Figure 7. Please see my comment above about the figures. The authors could consider to present this results as subplots 2x2. On the other hand, I think it would help the reader a great deal if the labelling on the panels were improved.
Citation: https://doi.org/10.5194/essd-2024-210-RC1 -
AC1: 'Reply on RC1', Montserrat Torne, 05 Dec 2024
First of all, we would like to thank the reviewer for their valuable comments, which will undoubtedly help us improve the quality of the manuscript. Regarding the minor edits, we have already incorporated them into the revised version of the paper. We will also attempt to expand the figures to double-column format, if feasible, and we will carefully review the errors and figure captions to align them with the reviewer’s suggestions.
As for the comment regarding the thermal conductivity of the crust,
The reviewer’s observation is correct: the crustal thermal conductivity value of 3.1 W/m·K is within the upper range. We intentionally selected this higher value to extend the range of sediment conductivity values considered in our analysis. Nevertheless, as the reviewer correctly notes, the critical threshold depth is determined solely by the thermal conductivity and thickness of the sediment layer. Crustal materials typically exhibit higher thermal conductivities than most sediments, particularly unconsolidated or porous ones. Since sediment conductivity is generally lower than that of the crust, a constant surface heat flow causes the depth of the isotherm to decrease with increasing sediment thickness until the critical threshold depth is reached. Importantly, this threshold depth is independent of crustal conductivity. However, if lower crustal conductivity values are assumed, the depth of the 150ºC isotherm would be shallower in regions where sediment thickness is below the threshold depth.
Furthermore, following the reviewer’s observation, we have slightly modified the corresponding paragraph (lines 505–512) to include a comment explaining why we have used a high crustal conductivity value. Now the paragraph reads as follows:
"Figure 7 shows the variations in the depth of the 150ºC isotherm in relation to sediment thickness, surface heat flow, and four different thermal conductivity values for the sediments (panels Fig. 7A to D). The calculated trend indicates that, for a constant measured surface heat flow and constant thermal conductivity, the isotherm depth decreases as sediment thickness increases until it reaches a critical threshold depth. Beyond this depth value, the isotherm is stable. Our results also show that, as expected, for a given thermal conductivity, an increase in surface heat flow leads to a relative shallowing of the isotherm, while a decrease in surface heat flow produces the opposite effect. Notably, an increase in thermal conductivity is associated with greater deepening of the 150ºC isotherm for the same heat flow and sediment thickness values. The crustal thermal conductivity value of 3.1 W/m·K, which is within the upper range of typical values, was selected to provide a broader range for assessing the influence of sediment thermal conductivity on subsurface thermal gradients. Importantly, this threshold depth is independent of the crustal conductivity. However, lower crustal conductivity values would result in a shallower depth of the 150ºC isotherm in regions where the sediment thicknesses are below the threshold depth"
Citation: https://doi.org/10.5194/essd-2024-210-AC1
-
AC1: 'Reply on RC1', Montserrat Torne, 05 Dec 2024
-
RC2: 'Comment on essd-2024-210', Anonymous Referee #2, 17 Dec 2024
The main objective of this short and well-illustrated paper is to present the open access database for sedimentary basins of Iberia and also its offshore basins, SedDARE-IB. This important database appears to include only Mesozoic and Cenozoic sedimentary successions (i.e. no Paleozoic or older sediments). If so, it would be useful to explicitly state this. The paper also presents maps of depth to base Cenozoic and Top Paleozoic stratigraphic markers. These maps are rather small and could be presented to greater advantage by filling the full page. The paper briefly describes the geological characteristics of the major onshore and offshore Iberian basins. Some attention is needed to complete and harmonize the data provided for each basin. An illustrative modelling of depth to the 150°C isotherm is presented with intriguing results, which require a clearer explanation. But I think this has already been addressed.
I recommend publication with minor revisions.
More detailed comments.
Line 42: replace ‘rocks sourcing them’ with ‘rockes in source areas’
Line 45 : replace ‘whose detailed knowledge’ with ‘ a detailed understanding of which’
Line 52 replace ‘is instrumentale for ‘ with ‘contributes to’
In the introduction it would be very useful to indicate the range of ages of the sedimentary succession in the database.
Line68 : replate ‘the applicability of’ with ‘the potential uses of’
Line 104 : replace ‘at c 156 Ma’ with ‘starting at c 156 Ma’
Line 107: replace ‘at about 118 Ma’ with ‘starting at about 118 Ma’
Line 114 : replace ‘salt-related’ with ‘salt-rich’
Line 130 replace ‘occurrence’ with ‘development
Section 2.2.1 Ebro Basin : Need to state clearly that this is a foreland basin.
2.2.2 Duero and Basque-Cantabrian basin : give thickness range, age range of sedimentary fill. Is this a foreland basin?
2.2.3 : give clear information on thickness range, age range of sedimentary fill.
2.2.5 : This setion is quite unlike the other basin descriptions. It describes the tectonic features and evolution of the Guadelquivir Basin but there is little information about the basins sedimentary fill. Would be good to give the same information for this basins as for the others.
Line 215: replace ‘Similarly to’ with ‘Like the’ or ‘With the’
Line 221/ replace ‘comprises’ with ‘ involves’
230: suggest completion of sentence ‘of the Acoustic Basement marker for most of the Western Mediterranean region, which is equivalent to the Base Cenozoic marker’.
Line 251: Estremadura Spur – needs to be shown on a figure
Line 259: outer shelf should read inner shelf?
259-260: Present day? sediment composition on the shelf varies with water? Depth
Line 275: shallow marine and shelf break limestones … what is the age of these sediments?
Line 279: Setubal and Asao Vicente – these localities need to be shown on a figure
Line 288: Replace ‘Neo-Tethys’ by ‘Atlantic’??
Line 291 : add: Carboniferous basement rocks of the SP2 zone (Fig.1b)
Line 292: I would say the Guadelquivir basin lies to the SE of this basin? – Also I’m wondering if it makes sense to make this statement as the Guadelquivir basin did not exist when the rift forming?
Between Lines 300 and 309 – clarify and harmonise the ages given for the development phases of the Algarve basin.
Line 358 : replace ‘differing’ with ‘new’?
Line 385: replace ‘limitations in terms of’ with ‘limited’
Line 397: replace ‘was’ with ‘were’
Figure 5 locate Valentia trough and Alboran Sea on the map.
Figure 5: Figure caption. I find the term ‘Paleozoic-cover sequence boundary’ unclear compared with ‘top of Paleozoic basement’. Im not sure I understand why you need to make this distinction?
Figure 5 : in caption replace ‘discordance’ with ‘unconformity’
420 : correct positions of brackets
437: replace ‘comprise’ with ‘provide’
479: replace ‘it serves’ by ‘it is identified’
Section 4 – influence of sediment thickness and nature on geothermal potential – Your response to the first reviewer has answered my request here to provide a clearer explanation of the model results.
Figure 7: You plot values for various basins but it is not clear how there data were gathered. A deeper discussion of their significance would be helpful to illustrate the relevance of your models.
Line 503: ‘other parameters considered ‘… Are these input parameters that are held constant in all the models?
Line 505 replace ‘concerning…..’ with ‘with varying sediment thickness and surface heat flow and for….’
Line 506: four different thermal conductivity values for the sediment’…. It would be very useful for the reader to appreciate the relevance of these values for real sedimentary basins?
Figure 7. Colour scale for depth to 150°C isotherm is I presume in km? add km to the scale or say in figure caption…
Line 541: replace ‘a rise’ with ‘an increase’
Data sets
SedDARE-IB: An open access repository of sediment data for Iberia and its continental margins Monterrsat Torne, Tiago M. Alves, Ivone Jiménez-Munt, Joao Carvalho, Conxi Ayala, Elsa C. Ramalho, Angela M. Gómez, Hugo Matias, Hanneke Heida, Abraham Balaguera, José Luis García-Lobón, and Jaume Vergés https://doi.org/10.20350/digitalCSIC/16277
Viewed
| HTML | XML | Total | Supplement | BibTeX | EndNote | |
|---|---|---|---|---|---|---|
| 540 | 98 | 20 | 658 | 31 | 17 | 18 |
- HTML: 540
- PDF: 98
- XML: 20
- Total: 658
- Supplement: 31
- BibTeX: 17
- EndNote: 18
Viewed (geographical distribution)
| Country | # | Views | % |
|---|
| Total: | 0 |
| HTML: | 0 |
| PDF: | 0 |
| XML: | 0 |
- 1