# Interaction between diagenesis and faulting in sandstone reservoirs: Inferences from the Groningen gas field

Job P.B. Arts, Dallyn Rodrigues, Fadi H Nader, Martyn R Drury, Liviu C

Matenco, Ernst Willingshofer, André R Niemeijer

► To cite this version:

Job P.B. Arts, Dallyn Rodrigues, Fadi H Nader, Martyn R Drury, Liviu C Matenco, et al. Interaction between diagenesis and faulting in sandstone reservoirs: Inferences from the Groningen gas field. Journal of Structural Geology, 2025, 201, pp.105554. 10.1016/j.jsg.2025.105554. hal-05410158

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Invited Research Article

# Interaction between diagenesis and faulting in sandstone reservoirs: Inferences from the Groningen gas field

<figure><img src="image_2.png" /></figure>

Job P.B. Arts<sup>a,∗</sup>, Dallyn Rodrigues<sup>a,†</sup>, Fadi H. Nader<sup>a,b</sup>, Martyn R. Drury<sup>a</sup>, Liviu C. Matenco<sup>a</sup>, Ernst Willingshofer<sup>a</sup>, André R. Niemeijer<sup>a,‡</sup>

## ARTICLE INFO

Keywords:

Structural diagenesis

Fault zone

Cementation

Groningen

Rotliegend

## ABSTRACT

We investigated the progressive diagenetic evolution of fault zones in the Rotliegend reservoir of the Groningen gas field (NE Netherlands) through microstructural and petrological analysis of cataclastic bands and the only retrieved fault gouge from the reservoir. Our observations show that authigenic quartz, ferroan dolomite, siderite and anhydrite are spatially associated with the presence of faults in the reservoir.

The uneven distribution of syntaxaxial quartz overgrowths in the host rock suggests that silica was readily available in the reservoir, but that quartz precipitation was inhibited by coatings and slow-growing euhedral faces. Quartz cementation was preferentially concentrated in cataclastic bands, where fresh fracture surfaces provided favourable nucleation sites.

Anhydrite and siderite cements are concentrated in dilatant fractures in cataclastic bands or in the host rock adjacent to it. Based on their association with dilatant fractures and the required sources for sulphates and reducing fluids, respectively, we interpret that they were introduced by extrinsic, fault associated fluids, during a late stage of the diagenetic history.

The preferential quartz cementation in cataclastic zones suggests that many Groningen faults experienced cementation-related strengthening, while this process was inhibited in the clay-rich fault cores as observed in the BIR-01 well, implying that fault reactivation is most likely to occur within the weak fault core.

## 1. Introduction

Subsurface exploitation of reservoirs for conventional or sustainable georesources and storage can induce various hazards, including compaction and seismicity (Foulger et al., 2018; Muntendam-Bos et al., 2022; van Thienen-Visser and Breunese, 2015). In particular, the reactivation of fault systems at the reservoir level or within its underlying and overlying strata remains poorly understood. This is due to the large variability in the differential pressure, composition, organization, and internal geometry of faults, related to differences in their tectonic and diagenetic histories (Fan et al., 2016; Foulger et al., 2018; Hennings et al., 2019; Keranen and Weingarten, 2018; Laubach et al., 2010; Zoback, 2007).

Faults are typically described as complex zones in the subsurface with a fault core, where most slip is accommodated, and an enveloping, less deformed damage zone (Caine et al., 1996; Faulkner et al., 2010; Torabi et al., 2020; Wibberley et al., 2008). The fault zone may comprise

breccias, cataclasites, fault gouges and clay smears, as well as rigid lenses (e.g. Caine et al., 1996; Collettini et al., 2009; Faulkner et al., 2003). The distribution of these various types of deformed rocks within the fault core and damage zone depends on host rock lithologies and their tectonic evolution (Torabi et al., 2020; Wibberley et al., 2008), as well as diagenetic processes that occurred before, during, and after fault activity (Knipe, 1993; Laubach et al., 2010, 2014).

Diagenesis refers to all the chemical, physical, and biological processes affecting sediments after their initial deposition, during burial and before low-grade metamorphism (Burley et al., 1985). Such processes are typically divided into diagenetic regimes or realms that are characterized by their physico-chemical conditions (Worden and Burley, 2003). These regimes are generally separated in eogenesis (or early diagenesis), controlled by depositional environment, mesogenesis, related to burial, and telogenesis or uplift-related diagenesis (Choquette and Lloyd, 1970; Worden and Burley, 2003).

In recent years, increasing attention has been given to the coupling

<footnote><sup>a</sup> Utrecht University, Department of Earth Sciences, Utrecht, the Netherlands</footnote>

<footnote><sup>b</sup> IFP Energies Nouvelles, Rueil-Malmaison, France</footnote>

<footnote>* Corresponding author.</footnote>

<footnote>E-mail address: j.p.b.arts@uu.nl (J.P.B. Arts).</footnote>
between deformation and diagenetic processes in sedimentary basins, referred to as structural diagenesis (e.g. Laubach et al., 2010). Previous studies have demonstrated that the interaction between diagenetic processes and fault rock formation plays an important role in controlling fault rock properties (Bense et al., 2013; Fisher and Knipe, 2001; Knipe, 1993; Laubach et al., 2009, 2010, 2014; Philit et al., 2015; Salomon et al., 2020). This interaction strongly depends on the host rock properties such as grain size, porosity, and mineralogy and affects the distribution of fluid flow pathways as well as the mechanical strength of the fault zone (Laubach et al., 2014). Due to possible differences with the surrounding host rock, a fault associated diagenetic realm may be defined in which the physico-chemical conditions are controlled by the presence of faults (Nader et al., 2024). Establishing a fault associated

diagenetic realm, enables a more accurate prediction of the intrinsic properties and mechanical behaviour of fault rocks at the basin scale (Nader et al., 2024).

Understanding the interaction between diagenetic processes and faulting is especially relevant for anthropogenic subsurface activities in faulted reservoirs. An important example of such a reservoir is the Groningen gas field in the northeastern Netherlands. The anthropogenic gas production from this reservoir caused induced seismicity on faults within the Rotliegend reservoir and the immediately adjacent lithologies (Dost et al., 2020; Smith et al., 2020; Spetzler and Dost, 2017; Willacy et al., 2019). This fault network of predominantly normal faults was created during various Paleozoic to Early Cenozoic tectonic phases, followed by a relative tectonic quiescence until the 1990s, thirty years

<figure><img src="image_3.png" /><figcaption>**Fig. 1.** – Geological setting of the Groningen gas field. a) Structural map with the distribution of the Permian Rotliegend Group in the area of the Netherlands (modified from Gast et al., 2010). Structural domains are indicated by abbreviations: TSB = Terschelling Basin, ALB = Ameland Block, LT = Lauwerszee Through, GP = Groningen Platform, EMSL = Ems Low, NS = Netherlands Swell, CNB = Central Netherlands Basin, WNB = West Netherlands Basin, RVG = Roer Valley Graben, LSB = Lower Saxony Basin. Black rectangle is the location of Fig. 1b; b) Structural map of the Groningen field with the depth of the Top Slochteren Formation (ROSL) and the associated fault polygons cross cutting this formation. The outline of the Groningen gas field is indicated by the white solid line. Locations of wells with sample material used in this study are shown by white triangles: BIR-01 = Bierum-01, EKL-12 = Eemskanaal-12, KPD-01 = Kooipolder-01, EKR-01 = De Eeker-01, ANV-01 = Annerveen-Veendam-01. Transect A-A' shows the location of the cross section in Fig. 1c. c) Seismic interpretation for SW-NE cross section through the Groningen Rotliegend reservoir and overlying and underlying formations (section displayed with 4x vertical exaggeration).</figcaption></figure>
after the gas production started (de Jager and Visser, 2017). Despite the advanced state of knowledge in terms of depositional facies, host rock diagenesis, and fault distribution in the Groningen gas field (de Jager and Visser, 2017; Gaupp and Okkerman, 2010; Grötsch et al., 2011; Kortekaas and Jaarsma, 2017; Van Ojik et al., 2012), little is known about the diagenetic processes and facies affecting the fault rock composition, its relationship with the tectonic history and the possible role of fluid-rock interactions in the millions of years of tectonic quiescence. Knowledge on the diagenetic alteration of the fault rocks in the reservoir is required to predict fault strength (Bos and Spiers, 2002; Cox, 2017; Hunfeld et al., 2020; Jeppson et al., 2023; van den Ende and Niemeijer, 2019) and the associated risk on human-induced seismicity (Li et al., 2023; van den Ende and Niemeijer, 2019). This knowledge is furthermore relevant for any other geological reservoirs, as diagenetic healing processes may affect the fault strength and its reactivation.

We characterize the fault rock composition and diagenesis in key samples of the Groningen gas reservoir including cataclastic bands, and the only fault gouge retrieved from the entire reservoir. We focus on the differences in diagenetic alterations between the host rocks and the deformed rocks and we use observations on dissolution and precipitation textures/relations to define the relative timing of diagenetic and faulting events. We show that authigenic quartz, ferroan dolomite, siderite and anhydrite are influenced by the presence of faults. Quartz cementation patterns can be explained by substrate availability between host rock and cataclasite and do not require extrinsic fluids, whereas iron-bearing carbonate and anhydrite distribution along faults is best explained by fault associated fluid circulation.

# 2. Geological evolution of the Groningen reservoir

## 2.1. Structural domains and tectonic history

The Groningen gas field is situated in a structural high (the Groningen platform) bounded by the Lauwerszee Trough to the west and the Eems Low to the east (Fig. 1; Doornenbal and Stevenson, 2010; Grötsch et al., 2011; Kombrink et al., 2012; Kortekaas and Jaarsma, 2017). The gas is hosted in the Permian Upper Rotliegend Slochteren sandstones at current depths between 2.5 and 3.2 km and reservoir temperatures of 95–110 °C (de Jager, 2007). The structural geometry is dominated by NNW-SSE striking normal faults with the largest offsets (up to 600 m) observed at the level of the Permian Rotliegend (Fig. 1b; Buijze et al., 2017; de Jager and Visser, 2017; de Keijzer and van Elk, 2008). The NNW-SSE striking faults are rooted into Carboniferous rocks, and may terminate at or align with the Dinantian carbonate platforms, which occur at depths of 5–6 km (Fig. 1c; Kombrink, 2008; Kortekaas et al., 2021; Kortekaas and Jaarsma, 2017). Some NNW-SSE faults are reverse faults or show an along-strike transition from normal to reverse offsets, attributed to a phase of inversion (de Jager, 2007; Kortekaas and Jaarsma, 2017). Reflection seismic observations also show the presence of E-W and N-S striking normal faults at the reservoir level, which are shorter (generally <10 km) than the NNW-SSE striking faults (Fig. 1b) and have offsets ranging between 25 and 250 m (Buijze et al., 2017). The northern sector of the gas field shows a lower density of faults with offsets generally smaller than 50 m (with exception of the NNW-SSE striking faults; Fig. 1).

Current interpretations generally assume that the NNW-SSE-oriented structural grain is a legacy of the Caledonian orogeny that sutured the Avalonia and Baltica continents (Smit et al., 2016 and references therein). Starting with the Late Triassic and continuing into the Jurassic and Early Cretaceous, northwestern Europe experienced a period of gradual rifting (Grötsch et al., 2011). Many of the fault systems at Rotliegend depth in the Groningen area are thought to have formed during this rifting period, creating the observed network of NNW-SSE, N-S, and E-W striking faults. Most of the observed normal fault offsets probably formed during the Late Jurassic - Early Cretaceous, coeval with the opening of the Central Atlantic (de Jager and Visser, 2017). This

deformation has created uplift of the Groningen Platform with respect to the Eems Low and Lower Saxony Basin to the east and the Lauwerszee Through to the west (Grötsch et al., 2011). The last significant deformation took place during the Late Cretaceous – Early Paleogene, when inversion took place in NW Europe due to collision in the Alps (e.g., Ziegler et al., 1995). This inversion is observed in the Groningen Field by several pulses of N-S oriented shortening inverting some of the NW-SE and E-W oriented faults (de Jager and Visser, 2017; Grötsch et al., 2011). The Groningen area remained tectonically quiescent since Early Paleogene times.

## 2.2. Lithostratigraphy and diagenetic history of the reservoir rocks

The reservoir rocks of the Groningen gas field consist of the Slochteren Sandstone Formation, that is made up of a sequence of aeolian and fluvial deposits (Fig. 2; de Jager, 2007; Van Ojik et al., 2012). In the southern part of the gas field and towards the base of the Slochteren Formation, coarser sandstones and conglomerates are encountered. The Rotliegend transitions into the clay-rich Silverpit Formation, with the Ten Boer claystone overlying most of the Slochteren Formation (Bouroullec and Geel, 2025; Van Ojik et al., 2012). Another clay-rich layer, the Ameland Claystone Member, separates the Slochteren Formation into a lower and an upper member only in the northern part of the Groningen field. The transition from conglomerates in the south, high-quality sandstones in the central region, and more clay-rich lithofacies in the north represents a proximal-distal relationship with a sediment input source located in the south (de Jager and Visser, 2017). The thickness of the Slochteren sandstone reservoir varies between 100 m in the south and 250 m in the north (Fig. 2; Buijze et al., 2017; de Jager and Visser, 2017). The thickness of the Ten Boer claystone member ranges between 20 m in the south and 80 m in the north (Fig. 2; Buijze et al., 2017; de Jager and Visser, 2017).

The Slochteren Formation unconformably overlies the Carboniferous shales of the Limburg Group, which consists of fine-grained siliciclastic sediments, shales, and intercalations of coal seams (Gast et al., 2010; Kombrink, 2008). The Ten Boer claystone is overlain by a 0.5- to 1 m thick shale layer known as the Coppershale Member and a sequence of anhydrites and carbonates referred to as the basal anhydrite (Bouroullec and Geel, 2025; Buijze et al., 2017). A thick sequence of Zechstein salt (primarily halite) overlies the basal anhydrites and rheologically decouples the deformation in the salt underburden from the deformation in the overburden (Fig. 1c; de Jager and Visser, 2017).

The diagenesis of the Slochteren Formation in the Groningen region has been linked to different environments with specific diagenetic products or phases (Amthor and Okkerman, 1998; Gaupp and Okkerman, 2010; Grötsch et al., 2011). An early shallow eogenetic, diagenetic phase includes many authigenic minerals whose distributions are largely controlled by pre-existing sedimentary facies (Gaupp and Okkerman, 2010; Grötsch et al., 2011; Morad et al., 2000; Worden and Burley, 2003). The mineral assemblage includes grain-coating illite, smectite and chlorite, as well as syntaxial quartz overgrowths and, to a lesser extent, feldspar overgrowths (Fig. 3; Clelland et al., 1987; Gaupp and Okkerman, 2010; Grötsch et al., 2011). The precipitation of pore filling cements including calcite, dolomite, and anhydrite with meteoric influence has also been associated with early diagenesis (Amthor and Okkerman, 1998; Gaupp and Okkerman, 2010; Grötsch et al., 2011; Miocic et al., 2020; Purvis, 1992).

Burial-related (mesogenetic) mineral phases include authigenic kaolinite, chlorite, illite and quartz cement (Gaupp and Okkerman, 2010; Grötsch et al., 2011; Morad et al., 2000; Worden and Burley, 2003). Carbonate cementation is believed to include a transition from predominantly dolomite to ferroan dolomite, and subsequently siderite (Fig. 3; Clelland et al., 1987; Vincent et al., 2018; Worden and Burley, 2003). Feldspar dissolution and mechanical compaction are also mesogenetic processes (Grötsch et al., 2011; Worden and Burley, 2003). The burial depth of the Rotliegend reservoir at the end of the first Late
<figure><img src="image_4.png" /><figcaption>**Fig. 2.** – Lithostratigraphic correlation of studied wells in the Groningen and Annerveen gas fields in the drilled Rotliegend and Carboniferous sections based on interpretation of geophysical well logs correlated with cores and samples (available in individual well reports at www.nlog.nl). Gamma ray measurements (GR) are shown by thin grey lines (NAM, 2022). Depths of samples are indicated by red arrows. Stratigraphic units: DC = Limburg Group (Carboniferous), ROSLL = Lower Slochteren Member (Slochteren Formation), ROCLA = Ameland Member (Silverpit Formation, ROSLU = Upper Slochteren Member (Slochteren Formation), ROCLT = Ten Boer Member (Silverpit Formation). Note that the Ameland Member (ROCLA) is present only in BIR-01 well, where a distinction between the Lower Slochteren and Upper Slochteren members is available (see also NAM, 2022).</figcaption></figure>

<figure><img src="image_5.png" /><figcaption>**Fig. 3.** – Burial plot with isotherms for the Rotliegend in the Groningen area. The burial curve and the temperature evolution are compiled from Amthor and Okkerman (1998) and Amberg et al. (2022). Dashed lines indicate the 50 °C and 100 °C depth-temperature isotherms. Diagenetic events in relation to the burial curve based on Clelland et al. (1987).</figcaption></figure>

Jurassic phase was more than 2.5 km (Amberg et al., 2022; Amthor and Okkerman, 1998). Quartz cementation occurred as silica became available through feldspar dissolution and pressure solution by gradual burial at higher temperatures and pressures (Giles et al., 2000; Worden and Burley, 2003; Worden and Morad, 2000).

The Late Jurassic – Early Cretaceous uplift resulted in erosion and removal of Lower Jurassic to upper Triassic units (de Jager and Visser, 2017). Uplift-related diagenetic (telogenesis) processes may include feldspar dissolution and oxidation of ferroan iron-bearing mineral phases (Gaupp and Okkerman, 2010 and references therein). Anhydrite cement precipitation in fractures is believed to be related to fault activity during this phase of uplift (Fig. 3; Clelland et al., 1987). Gas inclusions observed within the anhydrite suggest that precipitation occurred at the same time as the gas migrated into the Rotliegend reservoir (Speksnijder et al., 1988).

A second phase of burial occurred after the Jurassic – Early Cretaceous, when local gas emplacement likely hampered diagenetic

processes (Amthor and Okkerman, 1998; de Jager and Visser, 2017). Minor grain dissolution, illitization and quartz precipitation may have continued after gas emplacement, possibly supported by thin fluid films (Fig. 3; Clelland et al., 1987; Gaupp and Okkerman, 2010). Fracture-related cementation possibly also occurred during this phase (Gaupp and Okkerman, 2010).

### 3. Material and methods

We performed a petrographic and microstructural analysis on faulted and deformed samples from the Groningen gas field. The cross cutting and textural relations within and directly adjacent to faults are used to define the sequence of cementation and deformation processes (paragenetic sequence). This paragenetic sequence together with the available burial history of the Groningen reservoir (Amberg et al., 2022; Amthor and Okkerman, 1998) is then placed in the broader context of diagenetic realms in the reservoir to discuss relative relationships
between fault activity, fluid evolution, and diagenesis.

Sample material was retrieved from five wells in the Groningen and Annerveen gas fields (Figs. 1 and 2 and Table 1). Wells were selected based on proximity to major faults, previously interpreted in the Groningen field (NAM, 2020). Subsequently, well intervals were selected based on the presence of faults, fractures, or deformation bands visible in available core photographs (NAM, 2022). Samples from the Annerveen-Veendam-01 (ANV-01) well comprise pebbly sandstones and siltstones of the Slochteren Formation representative for most depth intervals in the south of the field (Fig. 2). Samples from de Eeker-01 (EKR-01) well represent (pebbly) sandstones found at the base of the Slochteren Formation (Fig. 2). Samples from the Kooipolder-01 (KPD-01) well and Eemskanaal-12 (EKL-12) well are derived from sandstone intervals at intermediate reservoir depths and represent the high permeability sandstones of the Slochteren Formation in aeolian/fluviatile depositional facies (Fig. 2). Finally, samples from the Bierum-01 (BIR-01) well are obtained from the more clay-rich Ameland Member of the Silverpit Formation, which shows an alternation between sandstone and claystone intervals. The BIR-01 samples are derived from sandstone intervals although clay-rich material is present within the shear zones and in the host rock material less than 1 m above and below our samples.

Samples retrieved from the ANV-01, EKL-12, KPD-01, and EKR-01 wells comprise small-offset (cm-scale) deformation bands within the Slochteren sandstone, representative for the damage zones of large-offset (>10 m) faults observed in reflection seismics. The BIR-01 samples comprise the only fault core material retrieved in the entire Groningen and Annerveen gas fields.

Based on sample macroscopic visual inspection, regions of interest were selected, and cross sections were cut perpendicular to the strike of faults and deformation bands for thin section preparation. Standard size, 30 µm thick, thin sections were stained for K-feldspar identification with Alizarin-red and Potassium Ferricyanide to differentiate between iron and non-iron bearing dolomites in optical microscopy using a Zeiss Primotech light microscope and Zeiss Axioscanner at Utrecht University.

Regions of interest were selected for high resolution scanning electron microscopy (SEM), using the Zeiss EVO 15 SEM and Zeiss Gemini 450 SEM at Utrecht University. Thin sections coated with a thin platinum or carbon coating, to prevent charging were analysed using backscatter electron (BSE-SEM) imaging in combination with electron dispersive X-ray spectroscopy (SEM-EDX) to identify detrital and authigenic mineralogy (typical beam settings; 5–15 kV and 0.3–1.0 nA). Colour-filtered cathodoluminescence (SEM-CL) images were recorded using a Delmic SPARC CL-system (integrated with the Zeiss Gemini SEM) to distinguish between detrital quartz grains and fragments from quartz cements in cataclastic zones (typical beam settings; 10 kV, 1.0 nA, 30 µs dwell time per pixel). Three filtered images (650, 550, and 450 nm) were combined to obtain RGB images, using the RGB plugin in the Odemis CL control software.

We qualitatively assessed grain size and sorting of the host rocks by visual inspection of the thin sections and using grain size and sorting charts (Supporting material S2; Folk, 1980; Wentworth, 1922). We quantitatively assessed the bulk rock mineralogy of faults and deformation bands as well as the host rock in the same thin section (Supporting S1). We performed point counting on optical images (1 plane-polarized image and 6 cross-polarized images), using JMicroVision software (Roduit, n.d., Version 1.2.4). For the deformed regions of interest, we additionally used the SEM-BSE and CL images as well as SEM-EDX point measurements. For point counting, we used a random grid with 300 points per region of interest. The statistical uncertainty in modal proportions from point counting was evaluated using Howarth (1998). For 300 points, the 95 % confidence interval for a measured mineral proportion of 5 % ranges between 3.11 and 7.59 %. For a measured mineral proportion of 50 %, it ranges between 45.10 and 54.90 %. We distinguished between intergranular porosity and dissolution porosity and between intergranular cements and replace

cements to obtain values for intergranular volume (IGV) (Paxton et al., 2002), compaction porosity loss (COPL), and cementation porosity loss (CEPL) (Lundegard, 1992; Makowitz and Milliken, 2003).

# 4. Results

## 4.1. Core samples

The sandstone intervals in the Slochteren Formation show steeply dipping (50–90°) narrow zones (tens of millimetres) of reduced grain size and porosity with respect to the host rock (Fig. 4a–b). These narrow zones typically show millimetre to centimetre-scale offsets and are interpreted as cataclastic deformation bands. The cataclastic bands occur as conjugate sets or as closely spaced (millimetres to a few centimetres) clusters with roughly the same orientation, enveloped by the undeformed host rock (Fig. 4a–b). These clusters of deformation bands show anastomosing patterns with occasional slip planes near their boundaries (Fig. 4a). Cataclastic zones in the ANV-01, EKR-01, and KPD-01 cores have a lighter colour appearance compared to the surrounding host rock, caused by cataclasis and the presence of diagenetic cements. Anhydrite cement is observed along deformation bands in the ANV-01 well and in filled fractures of the EKR-01 well (Fig. 4a–b).

The BIR-01 well intersects a 50 cm wide zone of deformed rocks including a 10 cm wide zone of ultracataclasites and clay-rich foliated fault gouges, interpreted as a fault core. The host rock at the sampled depth interval comprises fine to medium sandstones. We interpret that the clay-rich fault gouges are derived from claystone intervals in the Ameland member. A brecciated sandstone fragment is embedded in the clay-rich gouge, which we interpret as a host rock lens, incorporated in the fault core. The surrounding damage zone is characterized by a dense network of cataclastic deformation bands composed of fine-grained dark material (Fig. 4c). These bands include both steeply dipping (60–80°) synthetic and shallowly dipping (20–40°) antithetic structures. The band density of steeply dipping cataclastic bands is measured perpendicular to dipping direction and varies between 1.3 and 2.4 bands per centimetre. The total offset along the fault zone cannot be directly quantified from the well data, but the presence of a gouge-filled fault core and dense network of cataclastic bands in the surrounding damage zone are consistent with a metre-scale offset fault.

## 4.2. Host rock composition and diagenesis

The ANV-01 host rocks contain 50–60 % detrital quartz, and smaller amounts of detrital feldspar (<6 %) and lithic fragments (<11 %) and are classified as sublitharenites with medium sand grains that are moderately to poorly sorted (Table 1). The sandstone intervals of the EKL-12 and KPD-01 wells are composed of 53–60 % detrital quartz, 1–5 % detrital feldspar and 4–6 % lithics, and are classified as sublitharenites, showing fine-to medium grained textures with moderate sorting (Table S2). The EKR-01 sample contains 64 % quartz, 1 % feldspar, and 6 % lithics and is classified as sublitharenite with coarse sand texture and moderate sorting. The BIR-01 samples, located in sandstone intervals of the Ameland Member, have a host rock composition of 38–69 % detrital quartz, 0–7 % feldspar, and 1–6 % lithics, and are classified as quartzarenites, sublitharenites, and subarkose, with a fine-to medium grained texture and moderate to well sorting (Table 1). Detrital clays in the BIR-01 samples are difficult to distinguish from authigenic clays, due to compaction. Most detrital quartz grains in all lithofacies show concave-convex or indented grain boundaries (Fig. 5a). Furthermore, sutured grain boundaries (Fig. 5b) and stylolites (Fig. 5c) are observed. The detrital feldspar and lithic grains show irregular embayed margins, intragranular voids, and/or partial replacement by fine-grained material (Fig. 5d–f). These textures are consistent with alteration to clays and partial dissolution.

The total porosity (including intergranular and secondary porosity) ranges between 6 and 14 % for the ANV-01 pebbly sandstones, between
<caption>**Table 1**</caption>

Quantitative point counting results (volume %) for fault zone samples from the Groningen gas field. Sample ID and region of interest for point counting refer to the regions of interest shown in Supporting material S1. Host rocks are classified as quartzarenites (QA), sublitharenites (SLA), and subarkose (SA) based on detrital content (D). Fault rocks are classified as cataclastic bands (CB), fault gouge, and clay smear. Authigenic minerals are indicated with (A). We distinguish between intergranular porosity (IG) and dissolution porosity (DS). Intergranular volumes (IGV) are shown for the host rocks. Compaction porosity loss (COPL) and cementation porosity loss (CEPL) were calculated using the method of Lundegard (1992) assuming a depositional porosity of 40 % (Paxton et al., 2002).

<table><thead><tr><th>Sample + ROI</th><th>Type</th><th>Quartz (D)</th><th>Felspar (D)</th><th>Lithics (D)</th><th>Quartz (A)</th><th>Clays (A + D)</th><th>Dolomite (A)</th><th>Fe-Dolomite (A)</th><th>Siderite (A)</th><th>Anhydrite (A)</th><th>Kaolinite (A)</th><th>Porosity (IG)</th><th>Porosity (DS)</th><th>IGV</th><th>COPL</th><th>CEPL</th></tr></thead><tbody><tr><td>ANV-01_3072.5_1</td><td>Host SLA</td><td>51.3</td><td>6.0</td><td>10.0</td><td>0.7</td><td>5.3</td><td>4.7</td><td>1.3</td><td>5.0</td><td>0.7</td><td>1.0</td><td>10.0</td><td>4.0</td><td>26.0</td><td>18.9</td><td>13.0</td></tr><tr><td>ANV-01_3072.5_F1</td><td>Fault CB</td><td>62.3</td><td>2.7</td><td>0.0</td><td>27.0</td><td>2.7</td><td>0.0</td><td>0.0</td><td>0.0</td><td>1.3</td><td>1.0</td><td>3.0</td><td>0.0</td><td>-</td><td>-</td><td>-</td></tr><tr><td>ANV-01_3072.5_F2</td><td>Fault CB</td><td>34.3</td><td>0.7</td><td>0.7</td><td>0.3</td><td>0.0</td><td>1.0</td><td>0.0</td><td>1.7</td><td>58.7</td><td>0.7</td><td>0.7</td><td>1.3</td><td>-</td><td>-</td><td>-</td></tr><tr><td>ANV-01_3072.75_H1</td><td>Host SLA</td><td>60.0</td><td>6.0</td><td>6.3</td><td>0.3</td><td>6.3</td><td>2.3</td><td>1.0</td><td>4.3</td><td>2.7</td><td>4.3</td><td>5.0</td><td>1.3</td><td>25.7</td><td>19.3</td><td>16.7</td></tr><tr><td>EKL-12_2970_H1</td><td>Host SLA</td><td>54.3</td><td>1.7</td><td>5.7</td><td>0.3</td><td>8.3</td><td>7.7</td><td>3.0</td><td>5.7</td><td>0.0</td><td>2.3</td><td>6.7</td><td>4.3</td><td>32.3</td><td>11.3</td><td>22.8</td></tr><tr><td>EKL-12_2970_F1</td><td>Fault CB</td><td>59.3</td><td>0.0</td><td>3.0</td><td>18.3</td><td>1.7</td><td>7.3</td><td>2.0</td><td>6.0</td><td>0.0</td><td>0.0</td><td>2.3</td><td>0.0</td><td>-</td><td>-</td><td>-</td></tr><tr><td>EKR-01_2736.1_H1</td><td>Host SLA</td><td>63.7</td><td>1.3</td><td>6.0</td><td>5.3</td><td>6.3</td><td>6.0</td><td>1.3</td><td>2.7</td><td>0.0</td><td>1.0</td><td>5.0</td><td>1.3</td><td>25.3</td><td>19.6</td><td>16.3</td></tr><tr><td>KPD-01_2749.5_1_H1</td><td>Host SLA</td><td>60.3</td><td>2.7</td><td>4.7</td><td>0.7</td><td>8.3</td><td>3.0</td><td>1.0</td><td>3.0</td><td>0.0</td><td>4.3</td><td>9.3</td><td>2.7</td><td>27.3</td><td>17.4</td><td>14.9</td></tr><tr><td>KPD-01_2749.5_2_H1</td><td>Host SLA</td><td>53.7</td><td>3.7</td><td>5.7</td><td>1.7</td><td>8.7</td><td>1.7</td><td>0.3</td><td>6.0</td><td>0.0</td><td>8.0</td><td>7.0</td><td>3.7</td><td>30.0</td><td>14.3</td><td>19.7</td></tr><tr><td>KPD-01_2750.5_1_H1</td><td>Host SLA</td><td>60.3</td><td>5.3</td><td>5.3</td><td>2.0</td><td>11.0</td><td>0.7</td><td>0.0</td><td>0.7</td><td>0.0</td><td>2.3</td><td>6.0</td><td>6.3</td><td>21.0</td><td>24.1</td><td>11.4</td></tr><tr><td>KPD-01_2750.5_2_H1</td><td>Host SLA</td><td>60.3</td><td>1.3</td><td>4.3</td><td>1.0</td><td>7.7</td><td>0.0</td><td>0.7</td><td>4.0</td><td>0.0</td><td>5.7</td><td>7.7</td><td>7.3</td><td>24.0</td><td>21.1</td><td>12.9</td></tr><tr><td>BIR-01_2924.7_2_H1</td><td>Host SLA</td><td>57.0</td><td>5.0</td><td>5.0</td><td>0.3</td><td>20.0</td><td>2.0</td><td>1.3</td><td>2.7</td><td>0.0</td><td>0.0</td><td>2.7</td><td>4.0</td><td>22.7</td><td>22.4</td><td>15.5</td></tr><tr><td>BIR-01_2924.8_1_H1</td><td>Host SLA</td><td>66.8</td><td>1.6</td><td>2.6</td><td>0.3</td><td>18.8</td><td>0.0</td><td>0.3</td><td>0.3</td><td>0.0</td><td>3.6</td><td>0.7</td><td>4.9</td><td>19.1</td><td>25.9</td><td>13.7</td></tr><tr><td>BIR-01_2925.1_1_H1</td><td>Host QA</td><td>64.8</td><td>0.0</td><td>0.3</td><td>0.0</td><td>20.6</td><td>6.6</td><td>1.3</td><td>4.0</td><td>0.3</td><td>1.3</td><td>0.3</td><td>0.3</td><td>-</td><td>-</td><td>-</td></tr><tr><td>BIR-01_2925.1_1_F1</td><td>Fault gouge</td><td>60.3</td><td>3.3</td><td>0.0</td><td>2.3</td><td>24.0</td><td>0.0</td><td>0.0</td><td>0.0</td><td>0.0</td><td>0.0</td><td>10.0</td><td>0.0</td><td>-</td><td>-</td><td>-</td></tr><tr><td>BIR-01_2925.1_1_F2</td><td>Clay smear</td><td>38.0</td><td>0.0</td><td>1.0</td><td>0.3</td><td>54.0</td><td>2.3</td><td>1.0</td><td>0.3</td><td>0.0</td><td>2.0</td><td>0.0</td><td>1.0</td><td>-</td><td>-</td><td>-</td></tr><tr><td>BIR-01_2925.1_2_H1</td><td>Host QA</td><td>60.3</td><td>1.3</td><td>0.7</td><td>0.0</td><td>20.0</td><td>3.7</td><td>2.0</td><td>5.0</td><td>1.3</td><td>0.7</td><td>0.3</td><td>4.7</td><td>30.0</td><td>14.3</td><td>25.4</td></tr><tr><td>BIR-01_2925.2A_1_H1</td><td>Host QA</td><td>58.3</td><td>1.7</td><td>1.0</td><td>0.3</td><td>29.3</td><td>4.7</td><td>0.7</td><td>0.0</td><td>0.0</td><td>0.0</td><td>2.0</td><td>2.0</td><td>34.0</td><td>9.1</td><td>29.1</td></tr><tr><td>BIR-01_2925.2B_1_H1</td><td>Host SLA</td><td>38.7</td><td>3.7</td><td>4.7</td><td>0.0</td><td>1.7</td><td>25.7</td><td>16.3</td><td>4.7</td><td>0.0</td><td>0.0</td><td>2.7</td><td>2.0</td><td>48.3</td><td>-</td><td>-</td></tr><tr><td>BIR-01_2925.2B_2_H1</td><td>Host SLA</td><td>41.7</td><td>2.0</td><td>4.3</td><td>1.0</td><td>6.0</td><td>14.0</td><td>12.3</td><td>13.7</td><td>0.0</td><td>0.7</td><td>2.3</td><td>2.0</td><td>45.0</td><td>-</td><td>-</td></tr><tr><td>BIR-01_2925.6A_1_H1</td><td>Host SA</td><td>65.7</td><td>7.0</td><td>3.3</td><td>0.0</td><td>14.7</td><td>0.0</td><td>0.0</td><td>0.7</td><td>0.0</td><td>0.0</td><td>5.3</td><td>3.3</td><td>17.0</td><td>27.7</td><td>8.4</td></tr><tr><td>BIR-01_2925.6A_F1</td><td>Fault CB</td><td>73.7</td><td>1.7</td><td>0.0</td><td>15.7</td><td>4.3</td><td>0.0</td><td>0.0</td><td>0.3</td><td>0.0</td><td>0.0</td><td>4.0</td><td>0.3</td><td>-</td><td>-</td><td>-</td></tr><tr><td>BIR-01_2925.6B_1_H1</td><td>Host QA</td><td>68.7</td><td>2.3</td><td>1.7</td><td>0.7</td><td>18.3</td><td>0.0</td><td>0.0</td><td>0.7</td><td>0.0</td><td>0.0</td><td>3.3</td><td>3.3</td><td>18.3</td><td>26.5</td><td>11.0</td></tr><tr><td>BIR-01_2925.6B_2_H1</td><td>Host SLA</td><td>57.7</td><td>5.3</td><td>6.3</td><td>0.7</td><td>20.3</td><td>0.0</td><td>0.0</td><td>1.0</td><td>0.0</td><td>0.0</td><td>6.3</td><td>2.3</td><td>23.7</td><td>21.4</td><td>13.6</td></tr></tbody></table>
<figure><img src="image_6.png" /><figcaption>**Fig. 4.** Macroscopic observations on faults, fractures, and deformation bands in the core-slabs from the Groningen and Annerveen fields. (a) Well ANV-01, depth ~3072.5 m. The section shows different generations of cataclastic deformation bands in the upper part. The lower part shows anastomosing clastic deformation bands. (b) Well EKR-01, depth of ~2735 m. The section shows steep cataclastic bands with normal offsets (0.5–5 cm). Fractures have been cemented by anhydrite cement. Small offset (1–5 mm), less steep cataclastic bands are observed in the upper part of the slab. (c) Fault zone observed in core-slabs from the BIR-01 well in the Groningen field at a depth of ~2924.7 m. The top of the section shows complex anastomosing cataclastic deformation bands that are steeply dipping shear zones and breccias. The bottom of the section shows ultracataclasites, clay-rich foliated fault gouge, and a lens of brecciated material. These deformation features are interpreted as a fault core and the adjacent damage zone.</figcaption></figure>

6 and 15 % for the EKL-12, EKR-01 and KPD-01 sandstones, and less than 11 % for the BIR-01 sandstones intervals within the clay-rich Ameland Member (Table 1). The ANV-01 host rock samples have current intergranular volumes (IGV) around 26 % and between 16 and 21 % pore filling cement (Table 1; Table S2). Assuming an initial intergranular volume of 40 % (Paxton et al., 2002), the compactional porosity loss (COPL) is around 19 % and the cementation porosity loss (CEPL) is between 13 and 17 % (Table 1). The EKL host rock sample has a current IGV of 32 % and has 26 % pore filling cement. This sample has a COPL of 11 % and a CEPL of 23 %, showing that cementation contributes more to the porosity loss (Table 1). The EKR sample has an IGV of 25 % and 20 % pore filling cement. The COPL and the CEPL are 20 % and 16 %, respectively. Intergranular volumes for the KPD-01 samples range between 21 % and 30 %, with corresponding COPL values between 17 % and 24 %, and CEPL values between 11 % and 20 % (Table 1). The high current IGV values in these samples correspond to high percentages of pore filling (carbonate) cement (Table 1). The BIR-01 samples show a wide distribution in IGV values, ranging between 17 and 48 % (Table 1). The large clay content of these samples may comprise detrital clays which were difficult to distinguish from authigenic clays in the low porosity samples. For IGV below 26 % the COPL is larger than the CEPL. The porosity loss (COPL vs CEPL) was not determined for samples with intergranular volumes exceeding 40 %. These sample have a carbonate cement-supported fabric (Fig. 5j; Table 1).

**Authigenic quartz** is abundant in the sandstone facies of the EKR-01 sample (5 %) and varies between 0 and 2 % in the bulk rock of the BIR-01, EKL-12, KPD-01, and ANV-01 samples. It predominantly occurs as syntaxial overgrowths on detrital quartz grains (Fig. 6). Many detrital quartz grains show that grain-coating rims are preserved, which highlight the detrital grain boundaries (Fig. 6c–d). Overgrowths have an irregular distribution (Fig. 6a) and are often in contact with other detrital grain surfaces (Fig. 6a–d). Occasionally, small prismatic growths are observed on detrital quartz surfaces (Fig. 6a), regions with abundant

quartz cement do not show concave-convex grain boundaries (Fig. 6c–d).

**Dolomite** is the most abundant authigenic mineral phase (up to 26 % dolomite and 16.3 % ferroan dolomite) in the sandstone intervals of the Ameland Member (BIR-01), although there is a large variability in the studied samples. Authigenic dolomite is less abundant in the (pebbly) sandstones of the ANV-01, KPD-01, and EKL-12 wells (up to 8 % dolomite and 3 % ferroan dolomite). It occurs in two main forms: 1) non-planar (anhedral) cement with a mosaic texture, difficult to distinguish from the (partly) recrystallized early dolomite matrix (Fig. 5j); and 2) planar (euhedral rhombic) pore filling crystals (Fig. 5l–o). Occasionally, these crystals grow within the secondary pore space of leached grains (Fig. 5f). This type of authigenic dolomite commonly shows zoning or alternations between ferroan and non-ferroan dolomite (Fig. 5l–m). Although several alternations were observed, a general trend towards higher iron concentrations from core to rim of the crystals appears to be present (Fig. 5m). **Siderite** envelopes both dolomite and ferroan dolomite and forms a non-planar (anhedral), pore-filling cement (Fig. 5n) and shows a large variability in its occurrence; 0–14 % within the BIR-01 sandstone samples of the clay-rich Ameland Member, 0–6 % in the sandstone facies (EKL-12 and KPD-01) and 4–5 % in the pebbly sandstones (ANV-01).

**Clay mineral** cements are present as detrital grain coatings (Fig. 5d–g and i), detrital grain replacing clays (Fig. 5d–e), and pore-filling clays (Fig. 5h and m-o). In the point-counted data, we only distinguish between kaolinite and other clays (including illite, smectite, and chlorite) as the latter are often mixed and difficult to distinguish in optical microscopy. The pebbly sandstones (ANV-01) contain 1–4 % kaolinite and 5–6 % other clays. The sandstones (EKR-01, EKL-12 and KPD-01) contain 1–8 % kaolinite and 6–11 % other clays. The sandstones from the clay-rich Ameland Member contain less than 4 % kaolinite and other clays up to 29 %. Other clays in the BIR-01 well likely comprise detrital grains which were difficult to distinguish from authigenic clays in
<figure><img src="image_7.png" /><figcaption>**Fig. 5.** –Summary of main diagenetic features observed in thin-sections in the host rocks of fault samples from the Groningen reservoir, in the vicinity but outside faults cores and damage zones. a) Back-scattered image showing concave-convex detrital quartz (Q) grain boundaries (yellow triangles); b) Back-scattered image showing sutured grain boundaries between detrital quartz grains (yellow triangles); c) Stylolites between detrital quartz grains (black triangles); d) Back-scattered image of partly leached plagioclase feldspar (Fsp) grain and preserved grain rimming clays (cl); e) Back-scattered image of illite (i) replacing plagioclase feldspar (Fsp) grain. Two types of grain-rimming clays are observed: dark grey, tangential clays (likely illite; i) and bright fibrous grains (likely chlorite; cl). f) Optical microscopy image in plain-polarized light of partly leached lithic grain (Lg) and (partly) euhedral dolomite: g) Back-scattered image of perpendicular illite clay coatings (i) on detrital quartz (Q) and feldspar (Fsp) grains; h) Back-scattered image showing two generations of morphologically distinct kaolinite (k) booklets, one generation of pore filling, densely packed booklets and a second generation of loosely packed booklets; i) Optical microscopy image in plain-polarized light showing pore filling densely packed kaolinite booklets (k); j) Optical microscopy image in cross-polarized light showing dolomite cement (d) supported fabric; k) Optical microscopy image in cross-polarized light showing anhydrite cement (anh) supported fabric. l) Optical microscopy image in plain-polarized light of euhedral dolomite (d) grains and ferroan dolomite overgrowths (Fe-d; blue-stained); m) Back-scattered image showing kaolinite (k) booklets and rhombic ferroan dolomite (Fe-d) grain filling the remaining pore space. Zonation indicates variations in iron-enrichment of dolomite (bright = iron-rich); n) Back-scattered image showing one (ferroan) dolomite (Fe-d) grain pre-dating pore-filling siderite (s) cement. Note the bright disperse fibrous clays (cl), likely chlorite; Back-scattered image showing (ferroan) dolomite (Fe-d) rhombs and pore filling fibrous chlorite (cl) and kaolinite (k) booklets. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)</figcaption></figure>
<figure><img src="image_8.png" /><figcaption>**Fig. 6.** – Optical microscopy images of quartz cements in the host rock (left; plane polarized, right; cross polarized). a-b) Uneven distribution of syntaxial quartz (q) overgrowths on detrital grains (Q) in the KPD-01_2749.5 sample. Also see the small prismatic overgrowth to the top (qA). c-d) Quartz overgrowths (q) in contact with clay coats on other detrital grains and in contact with other overgrowths (sample EKR-01_2736.1). e-f) Quartz cement (qA and qB) filling the pore space between detrital grains (qA and qB) and ferroan dolomite (Fe-d) in sample EKR-01_2736.1. g-h) uneven distribution of syntaxial quartz overgrowths (q) and quartz cement (qA) filling the pore space between detrital quartz (qA) and ferroan dolomite (Fe-d) in sample EKR-01_2736.1.</figcaption></figure>

optical microscopy. *Authigenic kaolinite* occurs as pore filling clusters and appears in distinct morphologies: densely packed blocky agglomerates, loosely packed blocky agglomerates (Fig. 5i), and vermicular (worm-shaped) agglomerates (Fig. 5o). In some instances, (ferroan) dolomite crystals abut against or enclose kaolinite crystals (Fig. 5m), whereas in other instances both kaolinite and illite grow within the remaining pore space between (Fe-)dolomite crystals (Fig. 5o). *Illite/smectite* is observed as fibrous clay coatings (less than 5 µm) tangential (Fig. 5d-e) and perpendicular (Fig. 5g) to detrital surfaces of quartz and feldspar grains, although absent or very narrow at detrital grain contacts. Illite is also present in (partly) leached feldspar grains and forms a replacing phase (Fig. 5e). Iron-rich *chlorite* occurs as well defined coarse fibrous laths, forming overgrowths over pre-existing illite coatings (Fig. 5d-e). Occasionally chlorite forms dispersed pore-filling and grain bridging aggregates (Fig. 5n-o).

*Anhydrite* is only observed in the pebbly sandstone facies of the ANV-01 well (1–3 %) and the sandstones of the BIR-01 well within the Ameland Member (0–1 %). In the host rock, it occurs as dispersed pore-filling cement without preferred orientation of the crystal lattice (Fig. 5k).

### 4.3. Fault cements

*Quartz cement* is extensive in cataclastic deformation bands within the (pebbly) sandstones of the ANV-01, EKL-12, KPD-01 and EKR-01 wells (Figs. 7 and 8), ranging from 15 to 27 percent (Table 1). These cataclastic bands comprise large, fractured grains, embedded in a matrix of small fragments. The quartz cement is concentrated within intragranular fractures, leaving traces of fluid inclusions (Fig. 7d-f and 8b) and between the fresh surfaces of quartz fragments (Fig. 7d-f). Quartz cement is especially abundant where fracture aperture and distances between cataclastic fragments are small. Quartz amalgamates at the contact points between large quartz grains and small cataclastic fragments (Fig. 8b). Locally, cataclasites appear to be cement-supported and in contrast to the host rock, grain indentations are lacking (Fig. 7d-f). The false-colour cathodoluminescence images show a single dark blue emission signal for both intragranular and intergranular quartz cement (Fig. 7d-f). We found no evidence of fractures cutting the blue CL quartz. Clusters of deformation bands within the sandstones of the clay-rich Ameland Member (well BIR-01) similarly show dark blue CL quartz cement, concentrated within intragranular fractures or between cataclastic fragments and no evidence of fractures cutting the dark blue CL quartz (Fig. 9d). Grain boundaries of individual clasts can often still be observed in BSE images although quartz grains have locally well-developed, non-porous contacts resulting in amalgamation (Fig. 9c). Small scale grain indentations and interpenetrations are observed throughout the cataclastic zone (Fig. 9c-d).

The fault core of the BIR-01 well (Ameland Member) comprises two distinct domains: a clay-rich fault gouge with embedded quartz grains (Fig. 10a and g) and a grain-supported quartzofeldspathic gouge (i.e. ultracataclasite) with a fine-grained clay-rich matrix (Fig. 10b-d). The clay-rich gouge does not show any evidence of cementation by authigenic quartz and has a clay content of more than 50 %, exceeding that of the surrounding host rock (Table 1). Most of the quartzofeldspathic gouge is also uncemented, except for the regions close to the boundary of the domain (Fig. 10b-d). Small-scale grain indentations are present throughout the ultracataclasite, leading to amalgamation of grains (Fig. 10c).

*Anhydrite cement* is only observed in the pebbly sandstone facies of the ANV-01 well and in the sandstones of the clay-rich Ameland Member in the BIR-01 well. In the ANV-01 well, it occurs as pore filling cement (Fig. 7c) or as large poikilitic laths growing within fractures, with a preferred orientation of the longest axis parallel to the fracture walls (Fig. 7b). These poikilitic laths encapsulate detrital grains but also authigenic dolomite and siderite and appear to grow after removal of pre-existing fine-grained phases. In the BIR-01 well, poikilitic anhydrite is observed in open fractures within the host rock in the vicinity of the gouge (Fig. 10e). Notably, these dilatant fractures are almost perpendicular to the orientation of the clay-rich fault. Anhydrite laths encapsulate detrital grains and (ferroan) dolomite (Fig. 10e). The laths show corroded margins where in contact with the fracture pore space. Anhydrite is also observed as dispersed patches within the clay-rich gouge (Fig. 10f) and as pore-filling cement within sandstone clasts that are incorporated into the clay-rich fault gouge. These clasts typically show a cement-supported structure with predominantly dolomite and dispersed anhydrite cement (Fig. 10g).

Dispersed *authigenic siderite* is common in the bulk rock of all samples, whereas zones of more abundant siderite cementation are observed in the vicinity of quartz cemented cataclastic deformation bands (Fig. 11a and b) and open fractures in the Ameland Member (Fig. 11c). Siderite cement is concentrated in a narrow (~500 µm wide) zone on one side of the cataclastic band and has a dark brown appearance in plane-polarized images. The same sample also shows the presence of ferroan dolomite and kaolinite cements within the cataclastic zone and fractures (Fig. 11b-d).
<figure><img src="image_9.png" /></figure>

**Fig. 7.** Fault cementation in the sublitharenites of the ANV-01_3072.5 sample. a) Optical microscopy image in plain-polarized light showing sub-horizontal lamina of alternating (very) fine sand and coarse sand. Lamina have been displaced by conjugate steep, normal offset cataclastic bands (Cb); b) Poikilitic anhydrite (anh) cement localized within deformation band, partly replacing cataclastic grains. c) Back-scattered image showing quartz cemented cataclastic band (Cb). Anhydrite (anh) and siderite (s) cement are present in the pore space of the surrounding host rock; d-f) False SEM colour cathodoluminescent images (450, 550, and 650 nm monochromatic images) of the cataclastic band, comprising large (>50 µm) fractured detrital quartz (Q) grains surrounded by a matrix of predominantly angular quartz fragments and quartz cement (q). The quartz cement has a dark blue luminescence and is present concentrated between the fresh surfaces of cataclastic fragments within intragranular fractures. Detrital quartz (Q) shows a red, blue or purple luminescence. The pore space appears as yellow luminescence resulting from the epoxy resin. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

<figure><img src="image_10.png" /></figure>

**Fig. 8.** Cemented cataclastic band (Cb) in sublitharenite of the KPD-01_2749.5 sample. a) Back-scattered image showing that quartz cementation is concentrated within the cataclastic band; b) Grain amalgamation (q) between small (<10 µm) quartz fragments (Q) and large (>50 µm) fractured quartz grains (yellow arrows). Quartz cement (q) is also present within intragranular fractures in detrital quartz (Q) grains leaving traces of inclusions. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)
<figure><img src="image_11.png" /><figcaption>**Fig. 9.** Anastomosing cataclastic deformation bands within the damage zone of the BIR-01 well in a sample of sandstone intercalated in the Ameland Member clays. a) Optical microscopy image in plain-polarized light showing variations in porosity and grain size within the cataclastic zone); b) Back-scattered image showing a section within the anastomosing cataclastic deformation band. c) High magnification back-scattered image showing local grain amalgamation ('q' annotated yellow arrows) as well as grain indentations (yellow triangles) within the cataclastic band. d) False colour SEM cathodoluminescent image (450, 550, and 650 nm monochromatic images) showing that quartz cement (q) is concentrated in intragranular fractures and between small quartz fragments. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)</figcaption></figure>

# 5. Discussion

## 5.1. Paragenetic sequence based on fault zone diagenesis

We propose a sequence of mineral precipitation (paragenetic sequence), based on crosscutting microstructural relationships within fault zones in the Groningen Rotliegend gas field (Fig. 12). The paragenetic sequence in general agrees with previous diagenetic inferences in the Groningen area (Amthor and Okkerman, 1998; Gaupp and Okkerman, 2010; Miocic et al., 2020; Purvis, 1992; Vincent et al., 2018; Visser et al., 2016).

Mechanical compaction of sediments started directly after deposition. The preserved clay coatings between indented grain contacts (Fig. 5j) show that grain coatings probably were already present during deposition or that the precipitation of clays on detrital grains started before mechanical compaction was completed. In the sandstones of the clay-rich Ameland Member, anhedral dolomite cement precipitated locally before mechanical compaction started. The dolomite supported fabric prevented these samples from mechanical compaction resulting in the observed large IGV values (Table 1). Similarly, anhydrite cementation in the Ameland Member occurred during early burial, prior to mechanical compaction resulting in the anhydrite supported fabric (Fig. 5k).

Leaching of lithic fragments and detrital feldspar grains likely started during eogenesis due to the instability of these grains at surface conditions (e.g. Worden and Morad, 2000). The preserved clay coating rims in our samples (Fig. 5f) indicate that leaching of detrital feldspar and lithics postdated clay-rim formation with lithic fragments being replaced by vermicular kaolinite.

The leaching of feldspar grains and replacement by mixed illite and chlorite as well as kaolinite continued after mechanical compaction, during burial (mesogenesis), resulting in the observed intact (partly) leached mouldic pores (Fig. 5d and f). The precipitation of euhedral (ferroan) dolomite rhombs within these pores (Fig. 5f) indicates that dolomite precipitation continued after leaching of feldspars was initiated. During the first deep burial phase (mesogenesis, Fig. 12), mechanical compaction was followed by chemical compaction, producing

the concave-convex quartz grain contacts and sutured grain boundaries as a result of pressure dissolution (Fig. 5a–b). The compaction by pressure solution in the BIR-01 and KPD-01 wells is supported by IGV values below 26–30 % (Table 1; Paxton et al., 2002). Samples with large volumes of early dolomite cements did not further compact as shown by the high IGV values (Table 1).

Euhedral dolomite precipitated in the pore space after mechanical compaction. The zonation in rhombic (ferroan) dolomite shows that conditions changed with increasing burial and infiltration of reducing fluids (Fig. 5l–m). Encapsulation textures imply that siderite postdates ferroan and non-ferroan dolomite (Fig. 5n).

In our host rock samples the precipitation of authigenic quartz as syntaxial overgrowths is limited. The quartz cement supported fabric in the EKR-01 sample (Fig. 6c–d) however suggests that locally, silica was available before chemical compaction was dominant. The IGV value of 26.3 indeed suggests that chemical compaction was limited (Table 1). There is evidence for (ferroan) dolomite precipitation pre-dating quartz cementation (Fig. 6e–f).

The deformation by cataclasis in the Slochteren and Ameland sandstones (Figs. 7–9) suggests that these samples had obtained some degree of lithification prior to faulting. Hence, cataclastic deformation most likely occurred at depths of more than 1 km after the onset of lithification through compaction, cementation and dissolution (Fossen et al., 2018). The extensive quartz cementation of deformation bands postdates cataclasis as no fracturing of the blue CL quartz cement was observed (Figs. 7–9), while dolomite precipitation continued after the first phase of deformation (Fig. 10). The large concentration of siderite cement along the quartz cemented cataclastic band in the BIR-01 well (Fig. 11) suggests that cataclastic deformation and quartz cementation occurred prior to siderite cementation. However, quartz cementation may have persisted beyond the stage of siderite cementation. In plain-polarized light the dark brown appearance of siderite cements suggests that subsequent oxidation occurred, probably during uplift and the establishment of oxidizing conditions (telogenesis).

Anhydrite precipitation along deformation bands and within the fault gouge and open fractures (Fig. 7b–c and 10e–f) overlaps and postdates the initial cataclastic deformation, and encapsulation of
<figure><img src="image_12.png" /><figcaption>**Fig. 10.** Cementation within fault core of the BIR-01_2925.1 sample. a) Optical image in plain-polarized light showing a clay-rich fault gouge with sandstone clasts and grains embedded in a matrix of fine-grained clay. The gouge is bounded by anhydrite (anh) cemented and less deformed sandstone in the upper part and a brecciated lens in the lower part of the section. A narrow zone of quartzofeldspathic gouge (i.e. ultracataclasite) separates the clay-rich gouge from the brecciated lens; b) High magnification back-scattered image of the quartzofeldspathic ultracataclasite, exhibiting a quartz (Q) and feldspar (Fsp) clast supported fabric. Towards the boundary with the brecciated lens, localized quartz cementation (q) and grain amalgamation is observed. c) High magnification back-scattered image of a quartzofeldspathic gouge showing quartz grain indentations and a matrix consisting of fine-grained (submicron) clays and quartz; d) Back-scattered image showing quartz cementation (q) at the boundary of the quartzofeldspathic gouge; e) Back-scattered image showing poikilitic anhydrite laths (anh) in open fracture within the host rock. Inclusions of detrital quartz and dolomite (d) are present within the anhydrite crystals; f) Optical image in cross-polarized light showing anhydrite cement (anh) within the clay-rich gouge and surrounding host rock; g) Optical image in cross-polarized light showing a dolomite and anhydrite cemented sandstone clast embedded within clay-rich fault gouge.</figcaption></figure>

dolomite and ferroan dolomite shows that this is the latest phase (Fig. 12).

5.2. *Quartz cementation in fault zones*

The sources, transport, and precipitation of silica in diagenetic en-
vironments are a topic of abiding interest for host rock (McBride, 1989;
Taylor et al., 2022; Worden and Morad, 2000) and fracture properties
(Lander and Laubach, 2015; Laubach et al., 2014; Williams et al., 2015).
Quartz cementation under diagenetic conditions comprises three serial
steps: release of silica from source silicate minerals into the pore fluid,
silica transportation, and quartz cement precipitation. The slowest of
these steps controls or limits the abundance of quartz cements in natural
sandstones (Lasaga and Kirkpatrick, 1981; Taylor et al., 2022; Worden
and Morad, 2000). The precipitation step is widely considered to be rate
limiting in sedimentary basins with stagnant fluids and is controlled by
the surface area available for nucleation, temperature, and the grain size
of the detrital material (Lander et al., 2008; Lander and Walderhaug,
1999; Walderhaug, 1994). In contrast, when fluid advection is fast, for
example in permeable fault zones, fluid transport governs quartz accu-
mulation (Burley et al., 1989; Williams and Fagereng, 2022).

In our samples, the presence of clay coatings on detrital grains in the
host rock possibly decrease the surface area available for quartz nucle-
ation. The uneven distributions of quartz cement along detrital grain
boundaries with the presence of clays (Fig. 6a–d) and the large occur-
rence of detrital surfaces in contact with overgrowths from adjacent
grains (Fig. 6a–d) supports the influence of coatings on quartz cemen-
tation (Heald and Larese, 1974). Furthermore, the high abundance of
dolomite cement in some samples, further reduces the available nucle-
ation surface in the host rock. Although, syntaxial overgrowths in the
host rock of the EKR-01 sample are abundant, an intergranular porosity
of more than 6 % persists (Table 1). The preservation of porosity despite
the readily availability of silica may be attributed to the formation of
slow-growing euhedral terminations (Lander et al., 2008; Lander and
Laubach, 2015).

Preferred quartz cementation within intragranular fractures and on the fresh surfaces of cataclastic fragments in our samples suggests that precipitation on these nucleation sites is favourable. We attribute the enhancement of quartz precipitation in cataclastic bands to the formation of cataclastic fragments with fresh fracture surfaces. Previous studies suggested that these coating free surfaces are better nucleation sites with respect to the clay coated detrital grains (Fisher et al., 2000;
<figure><img src="image_13.png" /><figcaption>**Fig. 11.** Cataclastic deformation band within the damage zone of the BIR-01 well. a) Back-scattered image showing a cataclastic band, cemented by quartz and dolomite. Siderite cement is concentrated but not restricted to a zone adjacent to the cataclastic band; b) High magnification back-scattered image showing the sharp boundary between the quartz cemented cataclastic band and the siderite cemented host rock; c) Optical image in plain-polarized light showing euhedral siderite in an open fracture; d) Optical image in plain-polarized light showing (ferroan) dolomite in a dilated fracture.</figcaption></figure>

Fisher and Knipe, 1998, 2001; Lander et al., 2008; Milliken et al., 2005). More recent studies also showed that regardless of the presence of detrital grain coatings, quartz cementation rates strongly exceed those of the detrital grain boundaries (Williams et al., 2015). Faster quartz precipitation in these zones was attributed to the small aperture or spacing between cataclastic fragments preventing slow-growing euhedral terminations to form (Lander and Laubach, 2015; Williams et al., 2015). The preferred quartz cementation in small aperture fractures and between closely spaced cataclastic fragments in our samples agrees with this interpretation (Fig. 7f). The widely reported occurrence of syntaxial quartz overgrowths for the reservoir host rock in the Groningen gas field suggests that silica was readily available throughout the reservoir (Amthor and Okkerman, 1998; Clelland et al., 1987; Gaupp and Okkerman, 2010; Visser et al., 2016) and that an internal source for silica was also likely for the observed quartz cement in the cataclastic bands of our samples. Possible internal sources for silica include the observed feldspar dissolution and replacement by illite or kaolinite, illitization and chloritization of grain rimming smectite, and the chemical compaction of quartz by pressure solution (Fig. 5a–i; e.g. Worden and Burley, 2003).

The limited amount of quartz cement in the quartzofeldspathic fault gouges (with respect to the cataclastic bands in the damage zones) may be attributed to the reduction of available quartz nucleation surface due to pore filling and grain rimming clay minerals (Fig. 10c-d). Furthermore, the small grain size of the fault gouge possibly also promotes more rapid development of slow-growing euhedral crystal forms, inhibiting precipitation (Lander et al., 2008; Lander and Laubach, 2015). Finally, silica supply from the host rock to the fault gouge may be inhibited. The latter is supported by the observed clay-rich fault gouges directly adjacent to the quartzofeldspathic gouge in the BIR-01 well, which are possibly sealing (Fig. 10a–b).

The large abundance of the clays in the fault core (54 % versus 20–24 % in the adjacent host rock; Table 1) suggests that these clays are detrital in origin and were derived from claystone layers in the Ameland Member and mechanically smeared along the fault. At the same time, some of the clays in the BIR-01 host rock samples may also be detrital, explaining the overall higher background clay content of these samples

compared to other wells (Table 1).

### 5.3. Carbonate and anhydrite cementation in fault zones

Previous studies showed that late, post kinematic carbonate minerals are widespread in fractured sandstones (Laubach, 2003; Vincent et al., 2018; Weisenberger et al., 2019). The early pore filling dolomite in our samples does not show higher concentrations in association with faults and the spatial distribution shows a strong link with the presence of clay-rich intervals (Fig. 2 and Table 1) and suggests that the depositional environment had a large control. In contrast, ferroan dolomite and siderite show increased concentrations near cataclastic deformation bands and in open fractures (Fig. 11c and d). This relationship suggests that carbonate-saturated fluids possibly percolated along high permeability zones in the fault. The transition from dolomite to ferroan dolomite and siderite as shown by the enveloping relationships (Fig. 5m–n) suggests the availability of $Fe^{2+}$-rich, carbonate-saturated fluids and an evolution in pore fluid chemistry towards Ca and Mg depletion (see Worden and Burley, 2003). We interpret that the alternating zoning in ferroan dolomite in our samples (Fig. 5m) can be explained by repetitive episodic fluid migration along fault zones.

Fracture filling anhydrite cement has previously been observed in other Rotliegend sandstone reservoirs in the North Sea (e.g. Ligtenberg et al., 2011; Sullivan et al., 1994). We show that anhydrite cementation also occurred in fractures and fault gouges in the Groningen gas field. Based on the dispersed anhydrite patches within the clay-rich gouge of the BIR-01 well (Fig. 10f), we interpret that precipitation took place after faulting. The high concentration of anhydrite in and near the core suggests that sulphate-rich brines percolated through the fault zone, which at least temporarily acted as a conduit for fluids.

The relationship between anhydrite cement and the presence of cataclastic zones in the ANV-01 well is complex as evidenced by the different cementation patterns along the same band, replacing cataclasites within the deformed zone or precipitating anhydrite adjacent to the cataclastic band (Fig. 7b and c), indicating preferential flow along these zones. The focused fluid flow and anhydrite precipitation within the deformation band requires opening or dilatation of this low porosity
<figure><img src="image_14.png" /><figcaption>**Fig. 12.** – Interpretation of the diagenetic history (paragenetic sequence) for fault zones in the Groningen field, differentiated between host rock (blue), damage zone (orange) and fault core (red). Corresponding diagenetic realms and diagenetic facies tracts are indicated: MDFT = meteoric diagenetic facies tract, BDFT = basinal diagenetic facies tract, CDFT = compactional diagenetic facies tract, and FADFT = fault associated diagenetic facies tract. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)</figcaption></figure>

zone. The presence of fault roughness or dilatational bends may cause shear-induced dilatancy (Eichhubl et al., 2009; Knipe, 1992, 1993; Williams et al., 2015). However, there is no evidence for shearing after quartz cementation as observed by the lack of fractures in the dark blue CL quartz cement (Fig. 7d–f). Hence, we interpret that dilatation occurred in opening mode fractures along the cataclastic band. Strongly quartz cemented sections of the cataclastic band possibly did not dilate due to their increased strength with respect to the host rock. In these sections of the cataclastic zone, anhydrite precipitation occurred in the adjacent host rock (Fig. 7c).

## 5.4. Diagenetic facies tracts and cement distribution

The paragenetic sequence and interpretations of fault-related cements together with the available burial history of the Groningen reservoir (Amberg et al., 2022; Amthor and Okkerman, 1998) are implemented in a framework of diagenetic realms that reflect the interplay between evolving fluids and the presence of fault zones in the Groningen gas field. Such a framework provides a process-based categorization of the diagenetic products and can help to understand the spatial relationships between diagenesis and fault zones in the Groningen reservoir.

We adapt the conceptual framework of diagenetic facies tracts by Nader et al. (2024) in which four distinct diagenetic realms are defined: The basinal diagenetic facies tract (BDFT) comprises all diagenetic products formed from evolved seawater, infiltrating in and interacting with the sediments. The meteoric diagenetic facies tract (MDFT) groups

together all diagenetic products created by the interaction of meteoric fluids infiltrating in the sediments. The compaction diagenetic facies tract (CDFT) comprises diagenetic products resulting from temperature and pressure changes with burial. Specifically, for the CDFT, these diagenetic products precipitate from formation waters that have been saturated by mineral species, derived from an intrinsic or local source (e. g. by pressure solution or dissolution of detrital grains). Compaction fluids may be circulating through the reservoir or may be stagnant when compaction rates are low (e.g. during chemical compaction). Finally, the fault-associated diagenetic facies tract (FADFT) contains the diagenetic products that are influenced by extrinsic fluid migration along faults. The spatial-process framework of (Nader et al., 2024) relies on decades of work that show how host rock composition and texture together with burial and thermal history may influence diagenetic products and shows overlap with the temporal-burial framework (eogenesis, mesogenesis, and telogenesis; Choquette and Lloyd, 1970; Worden and Burley, 2003).

Based on the observed quartz cements in the EKR-01 host rock and the widely reported quartz cements in other studies on the Permian Rotliegend in the Netherlands and in the North Sea (Amthor and Okkerman, 1998; Gaupp and Okkerman, 2010), we interpret that silica was readily available throughout the reservoir. Silica enrichment and widespread quartz cementation from stagnant pore fluids typically only occurs in reservoirs that reside long enough within the so-called “silica mobility window” at temperatures above 90 °C (Giles et al., 2000; McBride, 1989). At these temperatures (and associated pressures) pressure solution, feldspar dissolution and clay mineral reactions contribute significantly to silica-enrichment of the pore fluids (Bjorkum
and Gjelsvik, 1988; Wilkinson et al., 2001; Worden and Burley, 2003; Worden and Morad, 2000).

Basin modelling studies show that the Groningen reservoir experienced burial temperatures above 90 °C during the Triassic-Jurassic and Paleogene (Fig. 12; Amberg et al., 2022; Amthor and Okkerman, 1998). During these periods, the sandstone reservoir was covered by a thick sequence of Zechstein rock salt and infiltration of surface derived waters was likely minimal. Based on the interpreted burial related local source, we ascribe the silica enrichment of pore fluids and quartz cementation in the reservoir to the compaction diagenetic facies tract (CDFT; Fig. 13).

The preferred quartz cementation in cataclastic bands in the damage zones of faults can be explained by textural and substrate differences with respect to the host rock (Lander et al., 2008; Lander and Laubach, 2015; Williams et al., 2015). Therefore, no extrinsic fluids are required to explain the cementation patterns in the fault zone, and we attribute quartz cementation in the fault zone to the compaction diagenetic facies tract (CDFT; Fig. 13a-b). Based on basin modelling studies (Amberg

et al., 2022; Amthor and Okkerman, 1998) and our observations on preferred quartz cementation in cataclastic bands, we expect that most cataclastic zones in the Groningen gas field will show similar cementation patterns.

Dolomite cementation has previously been attributed to early cementation from meteoric fluids (Amthor and Okkerman, 1998; Gaupp and Okkerman, 2010; Molenaar and Felder, 2019; Purvis, 1992), or carbonate and magnesium enriched compaction fluid expulsion from mudstone layers within the Rotliegend reservoir (Miocic et al., 2020). We attribute the dolomite supported fabric to early cementation from meteoric fluids and basinal fluids (MDFT and BDFT; Fig. 13a). The spatial distribution of dolomite in our samples shows a strong link with the presence of clay-rich intervals (Fig. 2 and Table 1) and suggests that the depositional environment had a large control. No fault-associated fluids are required to explain the dolomite cement distribution.

In contrast, we attribute the high concentration of ferroan dolomite and siderite near cataclastic bands and in fractures to fault associated

<figure><img src="image_15.png" /><figcaption>**Fig. 13.** – Conceptual model for diagenetic facies tracts (sensu Nader et al., 2024) for Rotliegend reservoirs widely distributed in Europe. a) Meteoric, basinal and compactional diagenetic facies tracts (DFTs) associated with early diagenesis in the absence of faults at the reservoir level; b) Interaction between the presence of fault zones and the compaction diagenetic facies tract associated with preferred quartz cementation in cataclastic bands. Silica is derived from the adjacent host rock, where compaction related pressure dissolution of quartz and feldspar dissolution release silica into the pore fluid. The lack of fresh substrate inhibits quartz cementation in the host rock; c) Fault associated diagenetic facies tract, associated with anhydrite and siderite cementation in cataclastic bands, derived from extrinsic fluids.</figcaption></figure>
fluids percolating through the fault zone (FADFT; Fig. 13c). Based on
stable carbon isotope analysis and radiogenic strontium isotope analysis,
previous studies interpreted that ferroan dolomite and siderite in
Permian Rotliegend reservoirs in the North Sea were derived from fluids
sourced from the organic-rich Carboniferous shales (Purvis, 1992; Vin-
cent et al., 2018). We interpret that the alternating zoning in ferroan
dolomite in our samples (Fig. 5m) can be explained by repetitive
episodic fluid migration along fault zones with fluids derived from the
Carboniferous shales. Repetitive zoning in ferroan dolomite is also
observed in the Rotliegend sandstones distant from faults (Gaupp and
Okkerman, 2010; Purvis, 1992). This is possibly explained by mixing of
cross-formational fluids that percolated along the fault into the reservoir
(Gawthorpe, 2003; Vincent et al., 2018; Worden and Burley, 2003).

Similarly, we interpret that the anhydrite cementation was derived
from fault associated fluids (FADFT; Fig. 13c) due to the large abun-
dance in and near faults and cataclastic bands. Previously, anhydrite
cements in Rotliegend reservoirs were attributed to the percolation of
alkaline brines derived from the Zechstein overburden based on sulphur
and oxygen isotopes (Gluyas et al., 1997; Speksnijder et al., 1988; Sul-
livan et al., 1994). Based on temperature constraints from oxygen iso-
topes, a Late-Jurassic – Early Cretaceous timing of anhydrite
cementation was derived and interpreted as a short-lived, tectonic
inversion induced event (Sullivan et al., 1994). Furthermore, gas in-
clusions within the anhydrite suggest its precipitation coeval with gas
emplacement in the Groningen reservoir (de Jager and Geluk, 2007;
Grötsch et al., 2011; Speksnijder et al., 1988).

Alternatively, the anhydrite may be derived from the remobilization
of pre-existing early anhydrite cements present within the reservoir.
Such early cements have been attributed to shallow groundwater related
diagenesis in damp sand and mud flat environments and have sulphur
isotopes consistent with meteoric fluids (Amthor and Okkerman, 1998).
For the ANV-01 well, such an intrinsic source is unlikely due to the lack
of claystones in the vicinity, and we adopt the interpretation of
Zechstein-derived, fault associated fluids. However, an intrinsic source
for anhydrite cannot be ruled out for the BIR-01 well, where the fault
core is located in a clay-rich facies, interpreted as sand and mud flat
deposits (Amthor and Okkerman, 1998).

In contrast to the preferred quartz cementation in the cataclastic
bands of all studied wells, ferroan dolomite, siderite and anhydrite only
showed precipitation in the cataclastic bands and fractures of some wells
(Table 1). Fault associated diagenetic products require the presence of
permeability pathways for extrinsic fluids to percolate along the fault
(Nader et al., 2024). Our data show that not all fault zones in the Gro-
ningen field acted as permeability pathways and the distribution of the
fault associated diagenetic products throughout the reservoir is difficult
to predict. Such a prediction still requires a better understanding of
changing fluid migration pathways in relation to stress changes in and
around the reservoir (Knipe, 1992, 1993) and in relation to diagenetic
alterations (Laubach et al., 2010).

5.5. Implications for fault strength and reactivation in the Groningen reservoir

Fault zone diagenesis can influence fault strength and fault slip
behaviour upon reactivation (Knipe, 1993; Laubach et al., 2010, 2014;
Williams and Fagereng, 2022). Especially for tectonically inactive res-
ervoirs like the Groningen gas field diagenetic processes could take place
during the millions of years of tectonic quiescence, effectively modifying
fault zone properties.

Our data shows that preferential quartz cementation in cataclastic
zones is expected throughout the Groningen sandstone reservoir, rein-
forcing these zones, leading to its strength increase with respect to the
surrounding host rock. Our interpretation agrees with experiments on
healed cataclastic zones under similar reservoir conditions showing a
strength increase in cemented faults when compared with the adjacent
host rock (Dewhurst et al., 2005; Dewhurst and Jones, 2002, 2003).

The lack of quartz cementation in the quartzofeldspathic fault gouge
in the Ameland member of the BIR-01 well suggests a larger potential for
fault re-activation in the fault core and for damage accumulation outside
the pre-existing damage zone altogether. This interpretation agrees with
the generally observed relationship between increased damage zone
width with fault offset (Fossen et al., 2018; Torabi et al., 2020). We
speculate that quartzofeldspathic gouges derived from Slochteren
sandstone intervals contain less (detrital) clay minerals and have a
larger substrate available for quartz cementation with respect to the
BIR-01 samples. Consequently, Slochteren Sandstone gouges possibly
show more quartz cementation. However, the Slochteren Sandstone
derived gouges are possibly less cemented than the observed cataclastic
bands in the ANV, EKL, EKR, and KPD wells, due to their fine-grained
nature, associated with slower quartz accumulation rates (Lander
et al., 2008; Lander and Laubach, 2015).

Extrinsically derived post kinematic anhydrite cement surrounds
cataclastic fragments and prevent or impede quartz cementation.
However, anhydrite cement possible contributes more to fault re-
strengthening than quartz as shown by its higher frictional strength
(Hunfeld et al., 2017; Pluymakers et al., 2016) and intact rock strength
(Hangx et al., 2010). Friction experiments furthermore suggest
increased seismogenic potential for anhydrite-derived gouges (Hunfeld
et al., 2017). Dedicated experiments are required to confirm the effects
of anhydrite cementation in sandstone derived cataclasites. Previous
experimental studies on fault slip of Slochteren sandstone and Ten Boer
claystone derived gouges (Arts et al., 2024; Hunfeld et al., 2017, 2020,
2021; Hung et al., 2025) did not take into account the potential
contribution of cementation to cohesion and fault strength, which is
relevant for the seismogenic behaviour of natural fault zones as
demonstrated by numerical and experimental simulations (Fisher et al.,
2019; Hooker and Fisher, 2021; van den Ende and Niemeijer, 2019).
Based on our observations, we suggest that the regeneration of cohesive
strength in cataclastic fault zones should be considered in future ex-
periments. These experiments should systematically assess the strength
of the Slochteren sandstone host rock, strength of the quartz, carbonate,
and anhydrite cemented damage zone, and finally, strength of the
uncemented fault gouge.

6. Conclusions

Through microstructural analysis, we identified the progressive
diagenetic interactions that affected the composition of fault zones from
samples obtained from the Rotliegend reservoir of the Groningen gas
field in NE Netherlands. Although a range of authigenic phases is present
in the host and fault rock, our microstructural observations highlight the
close relationship between quartz, anhydrite, ferroan dolomite and
siderite cementation with the presence of cataclastic fault zones.

Preferential accumulation of quartz cements in cataclastic bands is
attributed to the availability of microfracture surfaces free of nucleation
discontinuities such as clay coatings and early cements. Uneven syn-
taxial quartz overgrowths and small prismatic overgrowths in the host
rock suggest that such coatings as well as slow-growing euhedral crystal
faces limited quartz precipitation in the host rock but that silica was
readily available in the reservoir, possibly derived from the adjacent
host rock. Quartz cementation in the quartzofeldspathic gouge of the
BIR-01 well was inhibited by pore-filling and grain rimming clay min-
erals and possibly also by slow-growing euhedral terminations, which
form more rapidly on fine-grained quartz. Furthermore, silica supply
was possibly hampered by the low permeability clay smears in the fault
core.

Anhydrite cements concentrated in dilatant fractures in and adjacent
to cataclastic bands reflect precipitation from extrinsic, fault associated
fluids during a late stage of the diagenetic history. Similarly, episodic
migration of reducing iron-rich fluids along dilatant fractures can
explain the large concentration of ferroan dolomite and siderite within
the fault zones that acted as permeability pathways.
From a fault-mechanics perspective, the preferential quartz and anhydrite cementation in cataclastic fault damage zones implies that many faults within the Groningen reservoir have restrengthened by diagenetic alterations. Such restrengthening is possibly inhibited in clay-rich fault cores.

### CRediT authorship contribution statement

**Job P.B. Arts:** Writing – review & editing, Writing – original draft, Visualization, Validation, Resources, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. **Dallyn Rodrigues:** Writing – review & editing, Visualization, Validation, Resources, Methodology, Investigation, Formal analysis, Conceptualization. **Fadi H. Nader:** Writing – review & editing, Validation, Supervision, Methodology, Conceptualization. **Martyn R. Drury:** Writing – review & editing, Supervision, Methodology, Conceptualization. **Liviu C. Matenco:** Writing – review & editing, Supervision, Methodology, Conceptualization. **Ernst Willingshofer:** Writing – review & editing, Supervision, Project administration, Funding acquisition, Conceptualization. **André R. Niemeijer:** Writing – review & editing, Validation, Supervision, Conceptualization.

### Declaration of competing interest

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:

Job Arts reports financial support was provided by Dutch Research Council. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

### Acknowledgements

This study is part of research programme DeepNL, financed by the Netherlands Research Council (NWO), grant number: DEEP. NL.2020.012. We thank Leonard Bik, Erik Hellebrand, Richard Wessels, Maartje Hamers and Tilly Bouten (Utrecht University) for thin section preparation and support on the SEM work. The SEM data were obtained with equipment developed in the context of the EPOS-NL project (www.EPOS-NL.nl).

### Appendix A. Supplementary data

Supplementary data to this article can be found online at https://doi.org/10.1016/j.jsg.2025.105554.

### Data availability

The data used in for this manuscript is available via YODA (data repository Utrecht University): https://doi.org/10.24416/UU01-9R3193 Faulted samples from the Groningen gas field, the Netherlands (Original data) (Yoda Utrecht University).

### References

Amberg, S., Back, S., Sachse, V., Littke, R., 2022. Numerical 3D modeling of burial and temperature history, source rock maturity, and hydrocarbon generation in the onshore northeastern Netherlands. Int. J. Earth Sci. 111, 1033–1055. https://doi.org/10.1007/s00531-022-02168-3.

Amthor, J., Okkerman, 1998. Influence of early diagenesis on reservoir quality of Rotliegend sandstones, Northern Netherlands. Bulletin 82. https://doi.org/10.1306/00AA7F04-1730-11D7-8645000102C1865D, 1998.

Arts, J.P.B., Niemeijer, A.R., Drury, M.R., Willingshofer, E., Matenco, L.C., 2024. The frictional strength and stability of spatially heterogeneous fault gouges. Earth Planet Sci. Lett. 628, 118586. https://doi.org/10.1016/j.epsl.2024.118586.

Bense, V.F., Gleeson, T., Loveless, S.E., Bour, O., Scibek, J., 2013. Fault zone hydrogeology. Earth Sci. Rev. 127, 171–192. https://doi.org/10.1016/j.earscirev.2013.09.008.

Bjorkum, P.A., Gjelsvik, N., 1988. An Isochemical Model for Formation of Authigenic Kaolinite. K-Feldspar and Illite in Sediments.

Bos, B., Spiers, C.J., 2002. Fluid-assisted healing processes in gouge-bearing faults: insights from experiments on a rock analogue system. Pure Appl. Geophys. 159, 2537–2566. https://doi.org/10.1007/s00024-002-8747-2.

Bouroullec, R., Geel, C.R., 2025. Permian, In: Geology of the Netherlands. Amsterdam University Press, Amsterdam.

Buijze, L., van den Bogert, P.A.J., Wassing, B.B.T., Orlic, B., ten Veen, J., 2017. Fault reactivation mechanisms and dynamic rupture modelling of depletion-induced seismic events in a Rotliegend gas reservoir. Neth. J. Geosci. 96, s131–s148. https://doi.org/10.1017/njg.2017.27.

Burley, S.D., Kantorowicz, J.D., Waugh, B., 1985. Clastic diagenesis 18, 189–226.

Burley, S.D., Mullis, J., Matter, A., 1989. Timing diagenesis in the tartan reservoir (UK North Sea): constraints from combined cathodoluminescence microscopy and fluid inclusion studies. Mar. Petrol. Geol. 6, 98–120. https://doi.org/10.1016/0264-8172(89)90014-7.

Caine, J.S., Evans, J.P., Forster, C.B., 1996. Fault zone architecture and permeability structure. Geol. 24, 1025. https://doi.org/10.1130/0091-7613(1996)024<1025: FZAAPS-2.3.CO;2.

Choquette, P.W., Lloyd, C.P., 1970. Geologic nomenclature and classification of porosity in sedimentary carbonates. Bulletin 54. https://doi.org/10.1306/5D25C98B-16C1-11D7-8645000102C1865D.

Clelland, W.D., Kantorowicz, J.D., Nicholls, C.A., de Weerd, J., de Gier, F.A.M., 1987. Pilot study into the diagenesis of the northern Groningen wells: Stedum-1, Uithuizermeeden-1 and Delfzijl-1, onshore Netherlands. In: (Technical Service Report RKTR.87.282). Shell Research B.V., Rijswijk, The Netherland.

Colletti, C., Niemeijer, A., Viti, C., Marone, C., 2009. Fault zone fabric and fault weakness. Nature 462, 907–910. https://doi.org/10.1038/nature08585.

Cox, S.F., 2017. Rupture nucleation and fault slip: fracture versus friction. Geology 45, 861–862. https://doi.org/10.1130/focus0920172.1.

de Jager, J., 2007. Geological development. In: Geology of the Netherlands. Royal Netherlands Academy of Arts and Sciences, Amsterdam, pp. 5–26.

de Jager, J., Geluk, M.C., 2007. Petroleum geology. In: Geology of the Netherlands.

de Jager, J., Visser, C., 2017. Geology of the Groningen field – an overview. Neth. J. Geosci. 96, s3–s15. https://doi.org/10.1017/njg.2017.22.

de Keijzer, M., van Elk, J., 2008. Structural Evolution of the Groningen West-Periphery.

Dewhurst, D.N., Boult, P.J., Jones, R.M., Barclay, S.A., 2005. Fault healing and fault sealing in impure sandstones. In: Evaluating Fault and Cap Rock Seals. AAPG Hedberg Series, pp. 37–56.

Dewhurst, D.N., Jones, R.M., 2003. Influence of physical and diagenetic processes on fault geomechanics and reactivation. J. Geochem. Explor. 78–79, 153–157. https://doi.org/10.1016/S0375-6742(03)00124-9.

Dewhurst, D.N., Jones, R.M., 2002. Geomechanical, microstructural, and petrophysical evolution in experimentally reactivated catalASSES: applications to fault seal prediction. Bulletin 86. https://doi.org/10.1306/61EEDCA6-173E-11D7-8645000102C1865D.

Doornenbal, J.C., Stevenson, A.G., 2010. Petroleum Geological Atlas of the Southern Permian Basin Area. EAGE Publications b.v.

Dost, B., van Stiphout, A., Kühn, D., Kortekaas, M., Ruigrok, E., Heimann, S., 2020. Probabilistic moment tensor inversion for hydrocarbon-induced seismicity in the Groningen gas field, the Netherlands, part 2: application. Bull. Seismol. Soc. Am. 110, 2112–2123. https://doi.org/10.1785/0120200076.

Eichhubl, P., Davatzes, N.C., Becker, S.P., 2009. Structural and diagenetic control of fluid migration and cementation along the Moab fault, Utah. Bulletin 93, 653–681. https://doi.org/10.1306/02180908080.

Fan, Z., Eichhubl, P., Gale, J.F.W., 2016. Geomechanical analysis of fluid injection and seismic fault slip for the M<sub>w</sub> 4.8 Timpson, Texas, earthquake sequence. JGR Solid Earth 121, 2798–2812. https://doi.org/10.1002/2016JB012821.

Faulkner, D.R., Jackson, C.A.L., Lunn, R.J., Schlische, R.W., Shipton, Z.K., Wibberley, C. A.J., Withjack, M.O., 2010. A review of recent developments concerning the structure, mechanics and fluid flow properties of fault zones. J. Struct. Geol. 32, 1557–1575. https://doi.org/10.1016/j.jsg.2010.06.009.

Faulkner, D.R., Lewis, A.C., Rutter, E.H., 2003. On the internal structure and mechanics of large strike-slip fault zones: field observations of the carboneras fault in southeastern Spain. Tectonophysics 367, 235–251. https://doi.org/10.1016/S0040-1951(03)00134-3.

Fisher, D.M., Hooker, J.N., Oakley, D.O.S., 2019. Numerical models for slip on the subduction interface motivated by field observations. Lithosphere 11, 322–332. https://doi.org/10.1130/L1008.1.

Fisher, Q.J., Knipe, R.J., 2001. The permeability of faults within siliciclastic petroleum reservoirs of the North Sea and Norwegian Continental Shelf. Mar. Petrol. Geol. 18, 1063–1081. https://doi.org/10.1016/S0264-8172(01)00042-3.

Fisher, Q.J., Knipe, R.J., 1998. Fault Sealing Processes in Siliciclastic Sediments. 147. Special Publications, pp. 117–134. https://doi.org/10.1144/GSL SP.1998.147.01.08.

Fisher, Q.J., Knipe, R.J., Worden, R.H., 2000. Microstructures of deformed and non-deformed sandstones from the North Sea: implications for the origins of quartz cement in sandstones. In: Worden, Richard H., Morad, S. (Eds.), Quartz Cementation in Sandstones. Wiley, pp. 129–146. https://doi.org/10.1002/9781444304237.ch10.

Folk, R.L., 1980. Petrology of Sedimentary Rocks. Hemphill publishing company.

Fossen, H., Soliva, R., Ballas, G., Trzaskos, B., Cavalcante, C., Schultz, R.A., 2018. A Review of Deformation Bands in Reservoir Sandstones: Geometries, Mechanisms and Distribution, 459. Special Publications, pp. 9–33. https://doi.org/10.1144/SP459, 4.
Foulger, G.R., Wilson, M.P., Gluyas, J.G., Julian, B.R., Davies, R.J., 2018. Global review of human- induced earthquakes. Earth Sci. Rev. 178, 438–514. https://doi.org/10.1016/j.earscirev.2017.07.008.

Gast, R.E., Dusar, M., Breitkreuz, C., Gaupp, R., Schneider, J.W., Stemmerik, L., Geluc, M.C., Geißler, M., Kiersnowski, H., Glenn, K.W., Kabel, S., Jones, N.S., 2010. Rotliegend. In: Petroleum Geological Atlas of the Southern Permian Basin Area. EAGE Publications b.v., Houten, pp. 101–121.

Gaupp, R., Okkerman, J., 2010. Diagenesis and reservoir quality of Rotliegend sandstones in the northern Netherlands—A Review. In: The Permian Rotliegend of the Netherlands. SEPM Special Publications, pp. 193–226.

Gawthorpe, R.L., 2003. Burial dolomitization and porosity development in a mixed carbonate-clastic sequence: an example from the bowland Basin, Northern England. In: Burley, S.D., Worden, R.H. (Eds.), Sandstone Diagenesis. Wiley, pp. 413–438. https://doi.org/10.1002/9781444304459.ch24.

Giles, M.R., Indrelid, S.L., Beynon, G.V., Amthor, J., 2000. The origin of large-scale quartz cementation: evidence from large data sets and coupled heat–fluid mass transport modelling. In: Worden, R.H., Morad, S. (Eds.), Quartz Cementation in Sandstones. Wiley, pp. 21–38. https://doi.org/10.1002/9781444304237.ch2.

Gluyas, J., Jolley, L., Primmer, T., 1997. Element mobility during diagenesis: sulphate cementation of Rotliegend sandstones, Southern North Sea. Mar. Petrol. Geol. 14, 1001–1011. https://doi.org/10.1016/S0264-8172(97)00038-X.

Grötsch, J., Sluijk, A., Ojik, K. van, De Keijzer, M., Graaf, J., Steenbrink, J., 2011. The Groningen gas field: fifty years of exploration and gas production from a Permian dryland reservoir. In: The Permian Rotliegend of the Netherlands, pp. 11–33.

Hangx, S.J.T., Spiers, C.J., Peach, C.J., 2010. Mechanical behavior of anhydrite caprock and implications for CO₂ sealing capacity. J. Geophys. Res. 115, 2009JB006954. https://doi.org/10.1029/2009JB006954.

Heald, M.T., Larese, R.E., 1974. Influence of coatings on quartz cementation. J. Sediment. Petrol. 44, 1269–1274. https://doi.org/10.1306/212F6C94-2B24-11D7-8648000102C1865D.

Hennings, P.H., Lund Snee, J., Osmond, J.L., DeShon, H.R., Dommisse, R., Horne, E., Lemons, C., Zoback, M.D., 2019. Injection-Induced seismicity and fault-slip potential in the Fort Worth Basin, Texas. Bull. Seismol. Soc. Am. 109, 1615–1634. https://doi.org/10.1785/0120190017.

Hooker, J.N., Fisher, D.M., 2021. How cementation and fluid flow influence slip behavior at the subduction interface. Geology 49, 1074–1078. https://doi.org/10.1130/G48741.1.

Howarth, R.J., 1998. Improved estimators of uncertainty in proportions, point-counting, and pass-fail test results. Am. J. Sci. 298, 594–607. https://doi.org/10.2475/ajs.298.7.594.

Hunfeld, L.B., Chen, J., Hol, S., Niemeijer, A.R., Spiers, C.J., 2020. Healing behavior of simulated fault gouges from the Groningen gas field and implications for induced fault reactivation. J. Geophys. Res. Solid Earth 125. https://doi.org/10.1029/2019JB018790.

Hunfeld, L.B., Chen, J., Niemeijer, A.R., Ma, S., Spiers, C.J., 2021. Seismic slip-pulse experiments simulate induced earthquake rupture in the Groningen gas field. Geophys. Res. Lett. 48. https://doi.org/10.1029/2021GL092417.

Hunfeld, L.B., Niemeijer, A.R., Spiers, C.J., 2017. Frictional properties of simulated fault gouges from the seismogenic Groningen fault field under in situ P - t-Chemical conditions: friction of Groningen fault gouges. J. Geophys. Res. Solid Earth 122, 8969–8989. https://doi.org/10.1002/2017JB014876.

Hung, C.-C., Niemeijer, A., Aretusini, S., Spagnuolo, E., Chen, J., Hamers, M., 2025. Dynamic weakening in sandstone-derived fault gouges during simulated small-magnitude earthquakes under variable loading and environmental conditions. Geophys. J. Int. 241, 1009–1028. https://doi.org/10.1093/gji/gga077.

Jepsson, T., Lockner, D., Beeler, N., Hickman, S., 2023. Strength recovery in quartzite is controlled by changes in friction in experiments at hydrothermal conditions up to 200°C. JGR Solid Earth 128, e2022JB025663. https://doi.org/10.1029/2022JB025663.

Keranen, K.M., Weingarten, M., 2018. Induced seismicity. Annu. Rev. Earth Planet Sci. 149–174. https://doi.org/10.1146/annurev-earth-082517-010054.

Knipe, R.J., 1993. The Influence of Fault Zone Processes and Diagenesis on Fluid Flow.

Knipe, R.J., 1992. Faulting processes and fault seal. In: Structural and Tectonic Modelling and its Application to Petroleum Geology. Elsevier, pp. 325–342. https://doi.org/10.1016/B978-0-444-88607-1.50027-9.

Kombrink, H., 2008. The Carboniferous of the Netherlands and Surrounding Areas; a Basin Analysis. Utrecht University.

Kombrink, H., Doornenbal, J.C., Duin, E.J.T., Den Dulk, M., Ten Veen, J.H., Witmans, N., 2012. New insights into the geological structure of the Netherlands; results of a detailed mapping project. Neth. J. Geosci. 91, 419–446. https://doi.org/10.1017/S0016774600000329.

Kortekaa, M., Hettema, M., Spetzler, J., Wentinck, R., 2021. Groningen deep-seated fault systems and fault characteristics at seismic event locations. In: 82nd EAGE Annual Conference & Exhibition. Presented at the 82nd EAGE Annual Conference & Exhibition. European Association of Geoscientists & Engineers, Amsterdam, The Netherlands, pp. 1–5. https://doi.org/10.3997/2214-4609.202011530.

Kortekaa, M., Jaarsma, B., 2017. Improved definition of faults in the Groningen field using seismic attributes. Neth. J. Geosci. 96, s71–s85. https://doi.org/10.1017/jng.2017.24.

Lander, R.H., Larese, R.E., Bonnell, L.M., 2008. Toward more accurate quartz cement models: the importance of euhedral versus noneuhedral growth rates. Bulletin 92, 1537–1563. https://doi.org/10.1306/07160808037.

Lander, R.H., Laubach, S.E., 2015. Insights into rates of fracture growth and sealing from a model for quartz cementation in fractured sandstones. Geol. Soc. Am. Bull. 127, 516–538. https://doi.org/10.1130/b31092, 1.

Lander, R.H., Walderhaug, O., 1999. Predicting porosity through simulating sandstone compaction and quartz cementation. Bulletin 83. https://doi.org/10.1306/00AA9B4C-1730-11D7-8645000102C1865D, 1999.

Lasaga, A.C., Kirkpatrick, J., 1981. Kinetics of geochemical processes. In: Reviews in Mineralogy. Mineralogical Society of America, Washington, D.C.

Laubach, S.E., 2003. Practical approaches to identifying sealed and open fractures. Bulletin 87, 561–579. https://doi.org/10.1306/11060201106.

Laubach, S.E., Eichhubl, P., Hargrove, P., Ellis, M.A., Hooker, J.N., 2014. Fault core and damage zone fracture attributes vary along strike owing to interaction of fracture growth, quartz accumulation, and differing sandstone composition. J. Struct. Geol. 68, 207–226. https://doi.org/10.1016/j.jsg.2014.08.007.

Laubach, S.E., Eichhubl, P., Hilgers, C., Lander, R.H., 2010. Structural diagenesis. J. Struct. Geol. 32, 1866–1872. https://doi.org/10.1016/j.jsg.2010.10.001.

Laubach, S.E., Olson, J.E., Gross, M.R., 2009. Mechanical and fracture stratigraphy. Bulletin 93, 1413–1426. https://doi.org/10.1306/07270909094.

Li, M., Niemeijer, A., Dinther, Y.V., 2023. Why induced earthquakes occur on conventionally stable faults: frictional healing explains. https://doi.org/10.21203/rs.3-ss317840/v1.

Ligtenberg, H., Okkerman, J., De Keijzer, M., 2011. Fractures in the Dutch rotliegend - an overview. In: The Permian Rotliegend of the Netherlands. SEPM Special Publication, pp. 229–244.

Lundegard, P.D., 1992. Sandstone porosity loss; a "big picture" view of the importance of compaction. J. Sediment. Res. 62, 250–260. https://doi.org/10.1306/D42678D4-2B26-11D7-8648000102C1865D.

Makowitz, A., Milliken, K.L., 2003. Quantification of brittle deformation in burial compaction, frio and mount simon formation sandstones. J. Sediment. Res. 73, 1007–1021. https://doi.org/10.1306/051003731007.

McBride, E.F., 1989. Quartz cement in sandstones: a review. Earth Sci. Rev. 26, 69–112. https://doi.org/10.1016/0012-8252(89)90019-6.

Milliken, K.L., Reed, R.M., Laubach, S.E., 2005. Quantifying compaction and cementation in deformation bands in porous sandstones. In: Faults, Fluid Flow, and Petroleum Traps, pp. 237–249.

Miocic, J.M., Girard, J.-P., Schöner, R., Gaupp, R., 2020. Mudstone/sandstone ratio control on carbonate cementation and reservoir quality in Upper Permian rotliegend sandstones, offshore the Netherlands. Mar. Petrol. Geol. 115, 104293. https://doi.org/10.1016/j.marpetgeo.2020.104293.

Molenaar, N., Felder, M., 2019. Origin and distribution of dolomite in Permian Rotliegend siliciclastic sandstones (Dutch Southern Permian Basin). J. Sediment. Res. 89, 1055–1073. https://doi.org/10.2110/jsr.2019.58.

Morad, S., Ketzer, J.M., De Ros, L.F., 2000. Spatial and temporal distribution of diagenetic alterations in siliciclastic rocks: implications for mass transfer in sedimentary basins. Sedimentology 47, 95–120. https://doi.org/10.1046/j.1365-3091.200000007.x.

Muntendam-Bos, A.G., Hoedeman, G., Polychronopoulou, K., Draganov, D., Weemstra, C., Van Der Zee, W., Bakker, R.R., Roest, H., 2022. An overview of induced seismicity in the Netherlands. Neth. J. Geosci. 101, e1. https://doi.org/10.1017/njg.2021.14.

Nader, F.H., Matenco, L.C., Haq, B.U., 2024. Conceptualizing fluid-rock interaction diagenetic models with focus on tectonic settings. Earth Sci. Rev. 258, 104951. https://doi.org/10.1016/j.earscirev.2024.104951.

NAM, 2022. Core photographs of the Rotliegend reservoir of the Groningen gas field and surrounding areas. https://public.yoda.uu.nl/geo/UU01/6JHXY9.html.

NAM, 2020. Petrel geological model of the Groningen gas field, the Netherlands. https://doi.org/10.24416/UU01-1QH0MW.

Paxton, S.T., Szabo, J.O., Ajdukiewicz, J.M., Klimentidis, R.E., 2002. Construction of an intergranular volume compaction curve for evaluating and predicting compaction and porosity loss in rigid-grain sandstone reservoirs. Bulletin 86. https://doi.org/10.1306/61EEDDFA-173E-11D7-8645000102C1865D.

Philit, S., Soliva, R., Labaume, P., Gout, C., Wibberman, C., 2015. Relations between shallow cataclastic faulting and cementation in porous sandstones: first insight from a groundwater environmental context. J. Struct. Geol. 81, 89–105. https://doi.org/10.1016/j.jsg.2015.10.001.

Pluymakers, A.M.H., Niemeijer, A.R., Spiers, C.J., 2016. Frictional properties of simulated anhydrite-dolomite fault gouge and implications for seismogenic potential. J. Struct. Geol. 84, 31–46. https://doi.org/10.1016/j.jsg.2015.11.008.

Purvis, K., 1992. Lower permian rotliegend sandstones, southern north sea: a case study of sandstone diagenesis in evaporite-associated sequences. Sediment. Geol. 77, 155–171. https://doi.org/10.1016/0037-0738(92)90123-9.

Roduit, N., n.d. Microvision: Image Analysis Toolbox for Measuring and Quantifying Components of high-definition Images.

Salomon, E., Rotevatn, A., Kristensen, T.B., Grundvåg, S.-A., Henstra, G.A., Meckler, A. N., Albert, R., Gerdes, A., 2020. Fault-controlled fluid circulation and diagenesis along basin-bounding fault systems in rifts – insights from the East Greenland rift system. Solid Earth 11, 1987–2013. https://doi.org/10.5194/se-11-1987-2020.

Smit, J., Wees, J.-D.V., Cloetingh, S., 2016. The Thor suture zone: from subduction to intraplate basin setting. Geology 44, 707–710. https://doi.org/10.1130/G37958.1.

Smith, J.D., White, R.S., Avouac, J.-P., Bourne, S., 2020. Probabilistic earthquake locations of induced seismicity in the Groningen region, the Netherlands. Geophys. J. Int. 222, 507–516. https://doi.org/10.1093/gji/gga179.

Speksnijder, A., Kantorowicz, J.D., Clelland, W.D., de Gier, F.A.M., 1988. Pilot Study into Mechanical and Diagenetic Fault Sealing in the Groningen and Annerveen Gas Fields. NAM, onshore Netherlands.

Spetzler, J., Dost, B., 2017. Hypocenter estimation of induced earthquakes in Groningen. Geophys. J. Int. ggx020. https://doi.org/10.1093/gji/ggx020.

Sullivan, M.D., Haszeldine, R.S., Boyce, A.J., Rogers, G., Fallick, A.E., 1994. Late anhydrite cements mark basin inversion: isotopic and formation water evidence,
Rotliegend sandstone, North Sea. Mar. Petrol. Geol. 11, 46–54. https://doi.org/10.1016/0264-8172(94)90008-6.

Taylor, T.R., Lander, R.H., Bonnell, L.M., 2022. Chapter 10: origin of cements and replacements. In: Sandstone Petrography, Petrology, and Modeling. SEPM Society for Sedimentary Geology, pp. 224–274. https://doi.org/10.2110/sepmcsp.13.10.

Torabi, A., Ellingsen, T.S.S., Johannessen, M.U., Alaei, B., Rotevatn, A., Chiarella, D., 2020. Fault Zone Architecture and its Scaling Laws: where does the Damage Zone Start and Stop?, 496. Special Publications, pp. 99–124. https://doi.org/10.1144/SP496-2018-151.

van den Ende, M.P.A., Niemeijer, A.R., 2019. An investigation into the role of time-dependent cohesion in interseismic fault restrengthening. Sci. Rep. 9, 9894. https://doi.org/10.1038/s41598-019-46241-5.

Van Ojik, K., Böhm, A., Cremer, H., Geluk, M., De Jong, M., Mijnlieff, H., Nio, S.D., 2012. The rationale for an integrated stratigraphic framework of the upper Rotliegend II depositional system in the Netherlands. In: The Permian Rotliegend of the Netherlands. SEPM (Society for Sedimentary Geology), pp. 37–48.

van Thienen-Visser, K., Breunese, J.N., 2015. Induced seismicity of the Groningen gas field: history and recent developments. Lead. Edge 34, 664–671. https://doi.org/10.1190/tle34060664.1.

Vincent, B., Waters, J., Witkowski, F., Daniau, G., Oxtoby, N., Crowley, S., Ellam, R., 2018. Diagenesis of Rotliegend sandstone reservoirs (offshore Netherlands): the origin and impact of dolomite cements. Sediment. Geol. 373, 272–291. https://doi.org/10.1016/j.sedgeo.2018.06.012.

Visser, C., van Elk, J., Doornhof, D., 2016. Petrographic Study of Well Zeerijp-3A (ZRP-3A).

Walderhaug, O., 1994. Precipitation rates for quartz cement in sandstones determined by fluid-inclusion microthermometry and temperature-history modeling. J. Sediment. Res. 64, 324–333. https://doi.org/10.2110/jsr.64.324.

Weisenberger, T.B., Eichhubl, P., Laubach, S.E., Fall, A., 2019. Degradation of fracture porosity in sandstone by carbonate cement. Piceance Basin, Colorado, USA. Pet. Geosci. 25, 354–370. https://doi.org/10.1144/petgeo2018-162.

Wentworth, C.K., 1922. A Scale of grade and class terms for clastic sediments. J. Geol. 30, 377–392. https://doi.org/10.1086/622910.

Wibberley, C.A.J., Yielding, G., Di Toro, G., 2008. Recent Advances in the Understanding of Fault Zone Internal Structure: a Review, 299. Special Publications, pp. 5–33. https://doi.org/10.1144/SP299.2.

Wilkinson, M., Milliken, K.L., Haszeldine, R.S., 2001. Systematic destruction of K-feldspar in deeply buried rift and passive margin sandstones. J. Geol. Soc. 158, 675–683. https://doi.org/10.1144/jgs.158.4.675.

Willacy, C., van Dedem, E., Minisini, S., Li, J., Blokland, J.-W., Das, I., Droujinine, A., 2019. Full-waveform event location and moment tensor inversion for induced seismicity. Geophysics 84, KS39-KS57. https://doi.org/10.1190/geo2018-0212.1.

Williams, R.T., Fagereng, Å., 2022. The role of quartz cementation in the seismic cycle: a critical review. Rev. Geophys. 60, e2021RG000768. https://doi.org/10.1029/2021RG000768.

Williams, R.T., Farver, J.R., Onasch, C.M., Winslow, D.F., 2015. An experimental investigation of the role of microfracture surfaces in controlling quartz precipitation rate: applications to fault zone diagenesis. J. Struct. Geol. 74, 24–30. https://doi.org/10.1016/j.jsg.2015.02.011.

Worden, R.H., Burley, S.D., 2003. Sandstone diagenesis: the evolution of sand to stone. In: Burley, Stuart D., Worden, Richard H. (Eds.), Sandstone Diagenesis. Wiley, pp. 1–44. https://doi.org/10.1002/9781444304459.ch1.

Worden, R.H., Morad, S., 2000. Quartz cementation in oil field sandstones: a review of the key controversies. In: Worden, Richard H., Morad, Sadoon (Eds.), Quartz Cementation in Sandstones. Wiley, pp. 1–20. https://doi.org/10.1002/9781444304237.ch1.

Zoback, M.D., 2007. Reservoir Geomechanics. Cambridge University Press, Cambridge.