Introduction

For a long time, plate drift has been regarded as a major driving force in Earth’s geological history. For example, plate drift governs the opening and closing of ocean basins1,2, the breakup and assembly of supercontinents3,4,5, the evolution of climate6,7, the formation of various sedimentary basins8,9, and the development of hydrocarbon source rocks10,11,12. As a key parameter for quantifying plate drift effects, plate drift velocity has become an important topic in interdisciplinary research because of its controlling influence on significant global geological events. A series of geological, geophysical, and experimental observations have shown that plate drift velocity not only affects the geometry of slabs13 but also controls the timing of large igneous province volcanism14,15 and alters the chemical properties of oceanic rocks16. Despite the significant academic value and innovation these studies offer, our understanding of whether plate drift velocity directly influences the development of global hydrocarbon resources remains limited, with relatively few studies addressing this issue.

Hydrocarbon source rocks play a fundamental role in the exploration of underground oil and gas resources, as the abundance of organic matter directly determines their hydrocarbon generation potential. Generally, a higher organic matter content in rocks is associated with enhanced hydrocarbon generation capacity, thus increasing the potential for oil and gas resources17,18. For example, the Bakken shale in the Williston Basin of the United States typically has total organic carbon (TOC) contents exceeding 10%, making it a primary hydrocarbon source rock since the middle 20th century, with more than 20,400 horizontal wells drilled19 and contributing to the formation of large oil fields, such as the Elkhorn Ranch Field. Additionally, the Vaca Muerta shale in Argentina has TOC contents reaching 12%, providing abundant resources for the country’s first large-scale extraction project and marking a key milestone in Argentina’s energy revival20.

The Palaeozoic era was a critical period for both plate drift velocity changes and hydrocarbon source rock development. During this period, globally, plates underwent the convergence of Gondwana and Laurentia5,21,22,23, and numerous significant oil and gas fields were formed. Notable examples include the Ghawar field in Saudi Arabia, which is the world’s largest oil field24,25; the Elm Coulee field in the United States26; and the Tazhong and Fuman fields in Xinjiang, China27,28. Therefore, the Palaeozoic era serves as an ideal context for investigating the relationship between variations in plate drift velocities and the development of hydrocarbon source rocks.

In this study, we aim to accurately calculate the drift velocities of global plates during the Palaeozoic era on the basis of the latest plate reconstruction results23. Additionally, we conduct a statistical analysis of the C&C Reservoirs Database (2024), the S&P Global (formerly IHS Markit) EDIN Database (2024), and recently published literature on global Palaeozoic hydrocarbon source rocks. By establishing the relationship between plate drift velocities and levels of hydrocarbon source rock development, we aim to advance the frontiers of petroleum geology from a fresh perspective and offer a scientific basis for new global oil and gas discoveries.

Global plate drift velocities during the Palaeozoic

Accurate palaeogeographic reconstructions are essential for computing plate drift velocities. In recent decades, numerous scholars have conducted studies on the global reconstruction of plates during the Palaeozoic era5,29,30,31. Although the positions of some large plates in the global framework have essentially been confirmed3,21,32, significant uncertainties remain regarding the palaeogeographic positions of small plates3,5,21,33, such as the North China, South China, and Tarim Plates in central and western China. These uncertainties are due primarily to the effects of multiple episodes of magmatic activity and weathering, which often cause the remagnetisation of rocks, leading to a scarcity of reliable palaeomagnetic data. To address these challenges, our team collected palaeomagnetic core samples with minimal remagnetisation from these small plates and conducted systematic laboratory analyses23. Additionally, we integrated global palaeomagnetic databases, major geological events, and previous reconstruction models as constraints and references. Using GPlates software (www.gplates.org), we reconstructed the palaeogeographic positions of 29 major plates globally from the early Cambrian to the middle Permian (535–262 Ma)23 (Fig. 1). Based on these reconstructions, we further utilized the “Kinematics Tool” in GPlates to quantitatively calculate the plate drift velocities of plates globally at 1 Ma intervals. The results indicate that, except for the Kazakhstan Plate, which lacks reliable palaeomagnetic data, the plate drift velocities of the remaining 28 major plates during the Palaeozoic ranged from 0.10 to 25.76 cm/yr (Supplementary Dataset S1).

On the basis of exploration data, thirteen of the twenty-eight major plates, including those of Laurentia, Arabia, and Tarim Plates, developed hydrocarbon source rocks during the Palaeozoic period (535–262 Ma) (Supplementary Dataset S2). To quantify their characteristics of drift during hydrocarbon source rock formation, we applied the root mean square (RMS) velocity method34 to calculate the time-dependent plate drift velocities for these thirteen plates throughout the periods of hydrocarbon source rock development, referred to as RMS plate velocities. The RMS plate velocities are defined as.

$${v_{rms}}=\sqrt {\frac{{{v_1}^{2}+v{{_{2}^{{}}}^2}+{v_3}^{2}+ \cdot \cdot \cdot +{v_n}^{2}}}{n}}$$
(1)

where v is the velocity at a sampling node and n is the number of velocity sampling nodes during the periods of hydrocarbon source rock development.

The results indicate that the RMS plate velocities for these thirteen plates ranged from 0.97 to 12.76 cm/yr, with a clear division into three distinct intervals. The velocities in the first interval ranged from 0.97 to 5.00 cm/yr, and this interval contained 159 data points, accounting for 78% of the total; the velocities in the second interval ranged from 5.00 to 10.00 cm/yr, and this interval contained 43 data points, or 21% of the total; and the velocities in the third interval ranged from 10.00 to 12.76 cm/yr, with only 2 data points in the interval, representing 1% of the total. On the basis of this distribution, we classified the RMS plate velocities into three categories: low plate velocities (0.97–5.00 cm/yr), medium plate velocities (5.00–10.00 cm/yr), and high plate velocities (10.00–12.76 cm/yr) (Supplementary Dataset S2).

Fig. 1
figure 1

Evolution of the palaeogeographic position of major plates globally during the Palaeozoic, modified after Yang et al.23.

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Characteristics of global hydrocarbon source rock development in the Palaeozoic

Through systematic investigation and statistical analysis of Palaeozoic hydrocarbon source rock data from the C&C Reservoirs database (2024), the S&P Global EDIN database (2024), and previously published literature, this study provides a detailed overview of the number, regional distribution, basin distribution, stratigraphic distribution, palaeolatitude, rock type, and TOC content of hydrocarbon source rocks within the 13 studied plates (Supplementary Dataset S2). The results show that during the Palaeozoic period (from the early Cambrian to the middle Permian), a total of 204 hydrocarbon source rock units developed, distributed across 56 basins within the latitudinal range of 0° to 90°N/S.

In terms of regional distribution, Palaeozoic hydrocarbon source rocks were mainly concentrated within the basins of the Laurentia, Baltic, North China, South China, and Tarim Plates. Specifically, 65 units of hydrocarbon source rocks were present within twenty-one basins on the Laurentian Plate, accounting for approximately 32% of the total. The Baltic Plate contained 43 units within seven basins, accounting for approximately 21% of the total units. Although hydrocarbon source rocks were present in only three basins across the North China, South China, and Tarim Plates, they collectively accounted for 21% of the total, with 43 units.

In terms of stratigraphic distribution, although hydrocarbon source rocks were found in all the Palaeozoic strata, they were concentrated primarily in the Ordovician, Silurian, upper Devonian–lower Carboniferous, and upper Carboniferous–lower to middle Permian strata. The numbers of hydrocarbon source rocks in these strata were 34, 25, 62, and 48 units, respectively. Notably, the hydrocarbon source rocks of the Silurian, upper Devonian–lower Carboniferous, and upper Carboniferous–lower to middle Permian strata contributed approximately 25% of the global oil and gas reserves and are considered the primary hydrocarbon source rocks of the Palaeozoic35.

In terms of palaeolatitudinal distribution, hydrocarbon source rocks were concentrated predominantly in low-latitude regions (0–30° N/S), accounting for approximately 85% of the total. Specifically, 74 units (36% of the total) were located within 0–15°N/S, whereas 100 units (49%) were found within 15–30°N/S. In contrast, hydrocarbon source rocks were far less abundant in middle- and high-latitude regions (30–90° N/S), with only 30 units (15%) recorded. Among these units, 20 units (10%) were found within 30–45° N/S, 8 units (4%) within 45–60° N/S, and only 2 units (1%) within 60–90° N/S.

With respect to rock types, hydrocarbon source rocks were composed of predominantly claystone and carbonate source rocks, with smaller contributions from interbedded mixed and coal-bearing source rocks. Claystone source rocks, including mudstone and shale, were the most abundant, totalling 141 units (69%). Carbonate source rocks, consisting of limestone, muddy limestone, marl, and biogenic limestone, accounted for 39 units (19%). Interbedded mixed source rocks, comprising both claystone and carbonate components, represented 17 units (8%). Coal-bearing source rocks, including coal, carbonaceous mudstone, and mudstone, were the least common, with only 7 units (3%).

In terms of the TOC content, significant variations were observed among the different rock types. The claystone source rocks exhibited TOC contents ranged from 0.00 to 43.00%, with average TOC contents between 0.25% and 15.00%. The carbonate source rocks had TOC contents ranged from 0.00 to 14.00%, with average TOC contents ranged from 0.06 to 5.00%. The mixed interbedded source rocks presented TOC contents ranged from 0.00 to 27.00%, with average TOC contents ranged from 0.61 to 5.40%. The coal-bearing source rocks presented the highest TOC variations, with contents ranged from 0.52 to 85.00% and average TOC contents between 0.80% and 28.00% (Supplementary Dataset S2).

Analysis of the relationships between RMS plate velocities and levels of hydrocarbon source rock development

Relationships among RMS plate velocities, hydrocarbon source rock quantities, and TOC contents

1) Results of the RMS plate velocity analysis

A comparative analysis between the RMS plate velocities calculated via Eq. (1) and the quantity of hydrocarbon source rocks, as well as their TOC contents, revealed consistent trends across different rock types.

Among the 141 units of claystone source rocks, 109 units developed within plates with low velocities (0.97–5.00 cm/yr), accounting for approximately 77% of the total claystone source rocks. Their TOC contents ranged from 0.00 to 26.00%, with average TOC contents ranged from 0.25 to 15.00%. Thirty units (21%) developed within plates with medium velocities (5.00–10.00 cm/yr), with TOC contents ranged from 0.00 to 43.00% and average TOC contents ranged from 0.38 to 8.00%. Additionally, only two units developed within plates with high velocities (10.00–12.76 cm/yr), comprising 1% of the total claystone source rocks. The TOC contents of these samples ranged from 0.00 to 2.70%, with average TOC contents ranged from 0.90 to 1.00% (Fig. 2, Supplementary Dataset S2).

Among the 39 units of carbonate source rocks, 28 units developed within plates with low velocities (0.97–5.00 cm/yr), accounting for approximately 72% of the total carbonate source rocks. Their TOC contents ranged from 0.00 to 11.70%, with average TOC contents ranged from 0.06 to 5.00%. The remaining 11 units were associated with plates with medium velocities (5.00–10.00 cm/yr), comprising 28% of the total carbonate source rocks, with TOC contents ranged from 0.00 to 14.00% and average TOC contents ranged from 0.23 to 4.00%. Notably, no carbonate source rocks were identified within plates with high velocities (Fig. 3, Supplementary Dataset S2).

Seventeen units of interbedded mixed source rocks and seven units of coal-bearing source rocks displayed similar patterns. However, owing to their limited number, these categories are not discussed in detail here.

Fig. 2
figure 2

Comparative relationship between the RMS plate velocities and TOC contents of Palaeozoic claystone source rocks. (Detailed data can be found in Supplementary Dataset S2.).

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Fig. 3
figure 3

Comparative relationship between the RMS plate velocities and TOC contents of Palaeozoic carbonate source rocks. (Detailed data can be found in Supplementary Dataset S2.).

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2) Results of the trimmed mean TOC analysis

The trimmed mean is a statistical method used to compute the average of a dataset after extreme values are moved. In this approach, a portion of the dataset’s extreme values, typically the maximum and minimum values, are eliminated before the mean is calculated. By mitigating the influence of outliers, the trimmed mean enhances the accuracy and stability of the calculated average36,37,38.

By employing the trimmed mean statistical method, we calculated the average TOC contents of hydrocarbon source rocks, and the resulting value is termed the “trimmed mean TOC”. The relationship between the trimmed mean TOC content of hydrocarbon source rocks and the RMS plate velocity is delineated as follows: for the claystone source rocks, the trimmed mean TOC content was 3.36% for low plate velocities (0.97–5.00 cm/yr), decreased to 2.43% for medium plate velocities (5.00–10.00 cm/yr), and further decreased to 0.95% for high plate velocities (10.00–12.76 cm/yr) (Fig. 4, Supplementary Dataset S2). Similarly, for the carbonate source rocks, the trimmed mean TOC content was 1.32% for low plate velocities (0.97–5.00 cm/yr) and decreased to 1.11% for medium plate velocities (5.00–10.00 cm/yr) (Fig. 4, Supplementary Dataset S2). Overall, the trimmed mean TOC contents of both the claystone and carbonate source rocks tended to decrease with increasing RMS plate velocity, suggesting a negative correlation.

These findings indicate that the plate drift velocity plays a key role in controlling the development of hydrocarbon source rocks. Specifically, whether claystone or carbonate source rocks were considered, both the quantity and the trimmed mean TOC content of hydrocarbon source rocks were significantly greater during periods of low plate drift velocities (0.97–5.00 cm/yr) than during periods of medium or high plate velocities. Similarly, during periods of medium plate velocities (5.00–10.00 cm/yr), the quantity and trimmed mean TOC content of hydrocarbon source rocks remained higher than those associated with high plate velocities.

Fig. 4
figure 4

Relationships between the RMS plate velocity ranges and the trimmed mean TOC contents of the claystone and carbonate source rocks. (The detailed data used for calculations can be found in Supplementary Dataset S2.).

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Impact of various latitudinal ranges and plate stability on the level of hydrocarbon source rock development at uniform plate velocities

1) Impact of various latitudinal ranges on the level of hydrocarbon source rock development at uniform plate velocities

Owing to the limited number of interbedded mixed and coal-bearing source rocks, this section focuses primarily on the characteristics of development of claystone and carbonate source rocks. Statistical analysis of the number of source rocks and their trimmed mean TOC contents under the same range of plate velocity but varying palaeolatitudes reveals that both claystone and carbonate source rocks were significantly influenced by latitudinal variations in terms of their levels of development (Table 1; Fig. 5).

For example, during periods of low plate velocities (0.97–5.00 cm/yr), the maximum number of both claystone and carbonate source rocks occurs between 15°N/S and 30°N/S, followed by 0–15°N/S. A further decline was observed between 30°N/S and 45°N/S, followed by 45–60°N/S. In terms of the trimmed mean TOC content, the second optimal latitudinal range for claystone source rocks shifted to 30–45°N/S, whereas the trend for carbonate source rocks remained consistent with the pattern of latitudinal distribution of their quantity.

Under medium plate velocities (5.00–10.00 cm/yr), the distribution of claystone source rocks development remained aligned with the low plate velocity scenario, with the 15–30° N/S latitude range being the most favourable, followed by 0–15°N/S and then 30–45°N/S. However, carbonate source rocks exhibited a shift, with the 0–15° N/S latitude range becoming the most favourable, followed by the 15–30°N/S range. For the trimmed mean TOC content, the claystone source rocks presented the highest contents between 30°N/S and 45°N/S, followed by those at 15–30°N/S and then those at 0–15°N/S. The TOC trend for carbonate source rocks continued to mirror the distribution of their quantity.

During periods of high plate velocities (10.00–12.76 cm/yr), the number of developed source rocks was too limited to provide representative data. Therefore, no further detailed analysis was conducted.

Table 1 Impact of various latitudinal ranges on the levels of claystone and carbonate source rock development at uniform plate velocities.
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Fig. 5
figure 5

Comparative relationship of quantities and trimmed mean TOC contents of hydrocarbon source rocks across different latitudinal ranges at the same RMS plate velocity ranges. The bar graphs illustrate source rock quantities. The dashed line connects the trimmed mean TOC contents for cases with only one source rock, and this value is not representative. (The detailed data used for calculations can be found in Supplementary Dataset S2.).

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2) Impact of plate stability on the level of hydrocarbon source rock development at the same plate velocities and latitudinal ranges

Plate stability refers to a condition in which an entire plate or specific regions undergo minimal influence by peripheral tectonic activity and experience limited structural deformation. At the same plate velocities and latitudinal ranges, plate stability significantly affects the development of hydrocarbon source rocks. To examine this development, we analysed two distinct scenarios. In scenario A, the effects of plate size on hydrocarbon source rock development under identical geological periods, plate velocities, latitudinal ranges, and similar basin locations were analysed. In scenario B, the impact of different locations within the same plate on hydrocarbon source rock development under uniform geological periods, plate velocities, and latitudinal ranges was investigated.

In Scenario A, statistical analysis revealed that hydrocarbon source rocks on larger plates had significantly higher TOC contents than those on smaller plates. For example, hydrocarbon source rocks from the larger Baltic Plate presented notably higher TOC contents than those from the smaller Arabian Plate did, with an average TOC difference of 3.35%39 (see Supplementary Dataset S3). Similarly, within the larger Laurentia Plate, the Williston Basin had notably higher TOC levels in its hydrocarbon source rocks than those in the Tarim Basin on the smaller Tarim Plate, with an average TOC difference of 6.54% 40 (see Supplementary Dataset S3).

Scenario B comprised 19 datasets (see Supplementary Dataset S3), of which 16 datasets (84%) indicated that, regardless of plate size, hydrocarbon source rocks located closer to the central regions of plates exhibited significantly better development than those at the plate boundaries. The differences in the average TOC content ranged from 0.50 to 8.40%. For example, within the large Laurentia Plate, the hydrocarbon source rocks in the Michigan Basin (located in the central part of the plate) had a significantly higher average TOC content than those in the Black Warrior Basin (located at the southeastern edge of the plate), with a difference of 8.40% (see Supplementary Dataset S3). Similarly, within the medium-sized Arabian Plate, the hydrocarbon source rocks in the Mesopotamian and Central Arabian Basins (located in the central part of the plate) had significantly higher average TOC contents (5.30–6.00%) than those in the Western Arabian Basin, Zagros Basin (located at the northern edge of the plate), and Oman Basin (located at the southern edge of the plate), where the average TOC contents ranged from 0.50 to 3.00%41 (see Supplementary Dataset S3).

Collectively, these findings from both scenarios underscore the critical role of plate stability in controlling hydrocarbon source rock development.

Discussion and analysis of causation

Causal analysis of the influence of the RMS plate velocity on the quantity and TOC contents of hydrocarbon source rocks

To investigate how the RMS plate velocity affects the quantity and TOC contents of hydrocarbon source rocks, we propose that this influence results from the combined effects of organic matter accumulation, deposition rates, and anoxic conditions (Figs. 6 and 7).

1) Organic matter accumulation

The RMS plate velocity determines the time in which a plate remains in favourable climatic environments or advantageous geographic regions, which subsequently influences the development of hydrocarbon source rocks and the accumulation of organic matter. Specifically, plates with low velocities reside longer in favourable environments, providing sufficient time for original material and organic matter to accumulate, which promotes the formation of high-abundance hydrocarbon source rocks. In contrast, plates with high velocities spend less time in such environments, limiting organic matter accumulation and hydrocarbon source rock development.

This process can be vividly illustrated by the “bulldozer dynamic model” depicted in Fig. 6a. In this model, the bulldozer velocity represents the RMS plate velocity, whereas the soil mass collected in its shovel represents the organic matter required for hydrocarbon source rock development. At low plate velocities, the bulldozer moves slowly, allowing more time and opportunity for the shovel to accumulate a large amount of organic matter from favourable environments. This process promotes hydrocarbon source rock development, resulting in higher quantities and TOC contents within hydrocarbon source rocks (Fig. 6b). Similarly, at medium plate velocities, organic matter accumulation is moderate, leading to intermediate hydrocarbon source rock quantities and TOC contents (Fig. 6b). Conversely, at high plate velocities, rapid movement limits organic matter accumulation, resulting in the lowest quantities and TOC contents in hydrocarbon source rocks (Fig. 6b).

2) Deposition rate

Using data on the Palaeozoic global plate deposition rates reconstructed by Hay et al. (2006)42, in which the deposition rates ranged from 1.875 to 6.816 × 10¹⁸ kg/my, with an average rate of 3.22 × 10¹⁸ kg/my (Fig. 7a), we calculated the average deposition rates for different RMS plate velocity ranges. The results indicate that during periods of low plate velocities (0.97–5.00 cm/yr), the average deposition rate was moderate, at 3.051 × 10¹⁸ kg/my. Under medium plate velocities (5.00–10.00 cm/yr), the average deposition rate was relatively high, at 3.500 × 10¹⁸ kg/my. In contrast, during periods of high plate velocities (10.00–12.76 cm/yr), the average deposition rate decreased to a lower value, at 2.911 × 10¹⁸ kg/my (Fig. 6c).

The analysis suggested that a moderate deposition rate (approximately 3.051 × 10¹⁸ kg/my) associated with low plate velocities was the most favourable for hydrocarbon source rock development and organic matter preservation43,44,45. A moderate deposition rate facilitated the effective accumulation of sediments and the rapid burial of organic matter, thereby minimizing oxidation and decomposition, which ultimately enhanced the formation of high-abundance hydrocarbon source rocks. In contrast, high deposition rates (5.000–6.816 × 10¹⁸ kg/my) may have led to excessive dilution of organic matter, whereas low deposition rates (1.875–3.000 × 10¹⁸ kg/my) likely prolonged organic matter exposure to oxidizing environments, thereby increasing the risk of decomposition.

3) Global oceanic anoxic events (OAEs)

Studies have shown that during the Palaeozoic, the Earth experienced two glaciation events, three major mass extinction events, several large igneous provinces (LIPs) and oceanic anoxic events (OAEs). Previous research has suggested a significant correlation between these major geological events and the development of hydrocarbon source rocks with high organic carbon contents, as well as the occurrence of major oil and gas discoveries35.

By analysing shifts in inorganic carbon isotope composition (δ¹³C)46 and the global average plate drift velocity during the Palaeozoic, we found a strong isochronous correlation between periods of low plate velocities and one of the major global geological events—oceanic anoxic events (OAEs) (Fig. 7). Specifically, during periods of low plate velocities (0.97–5.00 cm/yr), 18 global OAEs occurred, including the ZHUCE event in the early Cambrian, the MDICE event in the middle Ordovician, and the Klonk event in the early Devonian. During periods of medium plate velocities (5.00–10.00 cm/yr), only six global OAEs occurred, such as the SPICE event in the late Cambrian and the Kanura event in the middle Permian (Fig. 7b). However, no corresponding OAEs were observed during periods of high plate velocities (10.00–12.76 cm/yr). The strong correlation between low plate velocities and global OAEs has two implications. On the one hand, low plate velocities tend to coincide with mass extinction events of animals and eukaryotes, providing a foundation of material for the large-scale burial of organic carbon47. On the other hand, anoxic conditions created favourable environments for the preservation of hydrocarbon source rocks. Together, these factors synergistically contributed to the development of high-abundance hydrocarbon source rocks.

Fig. 6
figure 6

Comprehensive evaluation of the impact of RMS plate velocities on source rock development levels. (a) Bulldozer dynamics model. (b) Comparative relationship of quantities and trimmed mean TOC contents of hydrocarbon source rocks across different latitudinal ranges under varying RMS plate velocity ranges. (c) Global plate average deposition rates for plates under different RMS plate velocity ranges. (d) Palaeoclimatic characteristics of different palaeolatitude intervals during the Palaeozoic under varying RMS plate velocity ranges. (e) Relationship between plate stability and levels of hydrocarbon source rock development under varying ranges of RMS plate velocities.

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Fig. 7
figure 7

Comparison of the global average plate drift velocity, deposition rate42, and global oceanic anoxic events (OAEs)46. (a) Correlation between the average Palaeozoic global plate drift velocity and global plate deposition rate. (b) Major carbon isotope excursions and global oceanic anoxic events (OAEs) during the Palaeozoic.

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Causal analysis of the influence of the latitudinal range and plate stability on the level of hydrocarbon source rock development at uniform plate velocities

1) Latitudinal range

The development of high-quality hydrocarbon source rocks relies on favourable palaeoclimatic and palaeoenvironmental conditions. Palaeolatitude variations influence hydrocarbon source rock development within the same RMS plate velocity range, likely because of the latitudinal distributions of Palaeozoic palaeoclimates, CO₂ levels, and precipitation.

Previous studies have shown that the Earth’s climatic zones, although not as regular and symmetrical as they are today due to the influence of monoglacial ice sheets and palaeocontinental configurations, still exhibited a basic latitudinal pattern during the Palaeozoic era. For example, the latitudinal range of 0–15°N/S was dominated by arid and tropical climates, that of 15–30°N/S was dominated by arid and warm temperate climates, that of 30–45°N/S was dominated by temperate climates, that of 45–60°N/S was dominated by temperate and cold climates, and regions above 60°N/S were dominated by polar climates (Fig. 6d)6,7.

Variations in CO₂ levels further influenced climate patterns across different latitudinal zones. For example, during the Ordovician, declining atmospheric CO₂ triggered global cooling48,49,50,51, with stronger effects in polar regions than in tropical regions52. This led to significantly higher palaeotemperatures between 0° and 15°N/S than at other latitudes (Fig. 6d)6,7,53. Additionally, precipitation followed a latitudinal pattern. Heavy rainfall was concentrated in the intertropical convergence zone (ITCZ) within 0–15°N/S, affecting the preservation of organic matter54,55,56 (Fig. 6d).

During periods of low plate velocities, hydrocarbon source rocks were formed predominantly in the late Palaeozoic (see Supplementary Table S1). During this time, warm palaeoclimatic conditions between 0° and 30° N/S were more favourable for biological activity and organic matter deposition than the cooler climates between 30°N/S and 60°N/S53,57,58,59. Within this range, moderate rainfall within 15–30°N/S promoted vertical water circulation within basins, mixing surface waters with nutrient-rich deep waters. This upwelling of nutrient-rich deep water enhanced primary productivity in surface waters, providing a more enriched material basis for hydrocarbon source rock formation. In contrast, arid conditions between 0° and 15° N/S limited biological productivity due to insufficient rainfall, whereas excessive leaching from heavy rainfall within the ITCZ potentially resulted in significant organic matter loss56. Therefore, the palaeoclimatic conditions within 15–30°N/S were the most favourable conditions for hydrocarbon source rock development (Fig. 6d).

During periods of medium plate velocities, hydrocarbon source rocks were formed primarily in the Ordovician strata (accounting for 60% of the total claystone source rocks and 73% of the total carbonate source rocks) (Supplementary Table S1). During this period, the global cooling event had a significant effect on the distribution of hydrocarbon source rocks. Since carbonate source rocks typically formed in warm shallow-marine environments, their primary distribution shifted from 15–30°N/S to 0–15°N/S. In contrast, claystone source rocks were less sensitive to temperature changes, and thus, their predominant distribution was maintained within the 15–30°N/S range.

Notably, an exception occurred from 30–45°N/S, where claystone source rocks presented higher TOC values than expected during periods of low and medium plate velocities (Figs. 5 and 6b). This anomaly likely resulted from large-scale marine transgressions, including postglacial transgression following the Late Ordovician Ice Age and tectonically driven transgressions (Fig. 6d). Previous studies have suggested that transgressions facilitated the influx of nutrient-rich deep water into basins, promoting surface-water eutrophication and leading to bottom water anoxia60,61. Thus, transgressions may have played a more significant role in organic matter accumulation than palaeoclimate and precipitation did.

2) Plate stability

Under the same RMS plate velocity and latitudinal conditions, plate stability plays a crucial role in the development of high-quality hydrocarbon source rocks. Plate size is a key factor influencing stability, as larger plates typically possess a thicker lithosphere and greater resistance to deformation. Furthermore, tectonic stress is more widely distributed across large plates, reducing localized tectonic disturbances62. These stable conditions promote organic matter accumulation and preservation, thereby enhancing hydrocarbon source rock development.

Plate stability is not uniform but varies significantly across different regions within the same plate. Areas near the plate centre experience minimal disruption from peripheral tectonic activities, resulting in greater stability, which favours hydrocarbon source rock development and promotes the accumulation and preservation of organic matter. In contrast, hydrocarbon source rocks near plate margins are often affected by oceanic subduction, plate collisions, and other tectonic activities, leading to unstable depositional environments. These conditions hinder organic matter accumulation and preservation, ultimately limiting the development of hydrocarbon source rocks.

For example, the Williston Basin is located at the centre of the large Laurentia Plate, where tectonic compression had a minimal impact. Its high stability ensured that sedimentation was controlled primarily by sea-level changes, resulting in an average TOC content of 7.21% in its hydrocarbon source rocks (see Supplementary Dataset S3). In comparison, although the Tarim Basin is centrally located within the Tarim Plate, its smaller size makes it more susceptible to intense compression from surrounding oceanic subduction and plate collisions. As a result, the Tarim Basin experienced significant tectonic uplift events, which decreased its stability and negatively affected organic matter accumulation and preservation, leading to an average TOC content of only 0.67% in its hydrocarbon source rocks40 (Fig. 6e).

In summary, low plate velocity played a crucial role in hydrocarbon source rock development by promoting organic matter accumulation and maintaining moderate deposition rates and anoxic conditions. Furthermore, under low plate velocity conditions, the combination of plate stability and latitudinal positioning between 15°N/S and 30°N/S further promoted the formation of high-abundance hydrocarbon source rocks.

Conclusion

Using the latest Palaeozoic (535–262 Ma) plate reconstructions, we calculated the plate drift velocities of twenty-eight major plates globally and conducted a statistical analysis of the abundance and TOC content of hydrocarbon source rocks within thirteen of these plates. Comparative analysis of the relationships between plate drift velocity and hydrocarbon source rock development revealed that low plate velocities (0.97–5.00 cm/yr) were most conducive to hydrocarbon source rock development, with average TOC contents generally exceeding 3%. This stage was followed by medium plate velocities (5.00–10.00 cm/yr), which still supported hydrocarbon source rock formation to a certain extent, with average TOC contents of approximately 2%. In contrast, high plate velocities (10.00–12.76 cm/yr) were relatively unfavourable for hydrocarbon source rock development, with average TOC contents of approximately 1%.

At the same plate velocity, the abundance of hydrocarbon source rocks was also influenced by palaeolatitude and plate stability. In terms of palaeolatitude, the region between 15°N/S and 30°N/S was the most favourable for the development of high-abundance source rocks, followed by 0–15°N/S, 30–45°N/S, and 45–60°N/S. The region between 60°N/S and 90°N/S was generally unfavourable for hydrocarbon source rock development. With respect to plate stability, large plates or locations near the plate centre were more conducive to the formation of high-abundance source rocks.

Genetic analysis suggests that the plate drift velocity determines the required organic matter accumulation, deposition rate, and frequency of anoxic conditions necessary for hydrocarbon source rock development. Moreover, at the same plate velocity range, variations in palaeolatitude and plate stability further regulate palaeoclimatic and depositional environments, exerting an additional influence on hydrocarbon source rock development.