Folarin Kolawole

Columbia University | CU · Department of Earth and Environmental Sciences

Recent widespread seismicity in Oklahoma is attributed to the reactivation of pre-existing, critically stressed and seismically unstable faults due to decades of wastewater injection. However, the structure and properties of the reactivated faults remain concealed by the sedimentary cover. Here, we explore the major ingredients needed to induce ear...

A continental rift is a nascent plate boundary where the lithosphere is thinned by tectonic activity. Some continental rifts undergo extension to the point that they generate a new ocean basin, whereas others can cease activity altogether. However, the mechanisms that determine rift success or failure remain debated. In this Review, we discuss fund...

Tectonic forces alone cannot drive rifting in old and thick continental lithosphere. Geodynamic models suggest that thermal weakening is critical for lithospheric extension, yet many active rifts lack volcanism, seeming to preclude this process. We focus on one such rift, the Tanganyika-Rukwa segment of the East African Rift System, where we analyz...

Continental rifts are thought to transition from a power-law fault length distribution during the juvenile stages of extension, to an exponential distribution during break-up and oceanic spreading. However, fault scaling relationships have rarely been quantified in natural incipient rifts, particularly in the absence of magmatic influence. We addre...

The heat budget of sedimentary basins is determined by heat transfer across the lithosphere-asthenosphere boundary and lithospheric heat sources, such that the tectonic evolution of their host continental and oceanic lithosphere ultimately impact the present-day heat flow and average geothermal gradients. Recent increase in availability of publicly...

In cratonic interiors, long-lived brittle shear zones host records of polyphase deformation, representing inherited structures that can host damaging earthquakes. Here, we explore the internal structure of the Kgomodikae Shear Zone (KSZ), signifying the western continuation of the ∼800-km long Precambrian Kgomodikae-Thabazimbi-Murchinson Fault Syst...

Continental rifting is an essential part of the tectonic cycle and is vital for understanding the Earth's evolution. However, knowledge gaps on lithospheric deformation processes that may initiate break-up remain. Here, we conduct a comparative multiscale study of the East African Rift System's magma-poor and magma-rich rift branches using one of t...

The understanding of the factors influencing the coalescence of intrarift fault segments in actively extending continental lithosphere is limited. The 2009 Mw6.0 Karonga earthquake occurred in the westernmost portion of the Northern Malawi Rift, which hosts clustered intrarift faulting. The 2009 event ruptured the strongly coalesced southern segmen...

Intraplate regions commonly host energetic earthquakes on less-prominent fault zones, raising questions on how fault structure may influence intraplate seismogenesis. Here, we investigate the causative fault of the strongly-felt April 5, 2024 Mw4.8 New Jersey Earthquake which occurred near the misoriented 300-km long Ramapo Fault. Field mapping of...

Continental rifts normally initiate within previously deformed lithosphere and thus their evolution and architecture can be largely controlled by inherited weak zones in the pre-rift crust. Here, we quantify the role of the strength and obliquity of pre-existing crustal-scale weak zones in the evolution of continental rift systems. We use a 3D nume...

Normal fault systems may grow by the lateral propagation of segments, yet little is known about the timescales over which this may occur and the implications for rift propagation. Footwall bedrock river networks provide a means to delineate the recent fault displacement patterns since erosional landscapes are sensitive recorders of rock uplift hist...

We investigate the upper-crustal structure of the Rukwa–Tanganyika rift zone in East Africa, where the Tanganyika rift interacts with the Rukwa and Mweru-Wantipa rift tips, evidenced by prominent fault scarps and seismicity across the rift interaction zones. We invert earthquake P-wave and S-wave travel times to produce 3D upper-crustal velocity mo...

West Africa continues to host a growing number of low and intermediate-magnitude earthquakes (M2-5) along its passive margins, and its continental interior. Earthquake activity in these regions raises the need to comprehend the causes and the tectonic controls of the seismicity. Unfortunately, such studies are rare. Here, we apply single-station in...

The tectonic interaction, linkage, and coalescence of propagating continental rift segments eventually create a through-going axial rift floor without which a break-up axis cannot develop. However, prior to linkage, interacting rifts are separated by a topographic basement-high (rift interaction zone, RIZ) which is progressively dismembered and dow...

Rifted continental margins record distinct phases of tectonic extension that include a stretching phase, necking phase, in some cases, hyperextension, and finally break-up. The necking phase is critical for the success of a divergent plate boundary, and the conventional paradigm suggests a cessation of faulting in the proximal domain as tectonic st...

West Africa continues to host a growing number of low and intermediate-magnitude earth- quakes (M2-5) along its passive margins, and its continental interior. Earthquake activity in these regions raises the need to comprehend the causes and the tectonic controls of the seismicity. Unfortunately, such studies are rare. Here, we apply single-station...

Active or man-made seismic sources are often used to delineate subsurface geologic structures via seismic imaging techniques. Although conventional controlled seismic sources have provided high-resolution subsurface images, the high cost of data acquisition necessitates improved use of cheaper alternative seismic sources for subsurface imaging, suc...

The oldest structures in a rift basin define incipient rift architecture, and commonly modulate the patterns of landscape evolution, sedimentation, and associated hazards in subsequent phases of rift development. However, due to deep burial beneath younger, thick syn‐rift sequences, and limited resolution of seismic imaging, critical early‐rift pro...

Study Region: Mkonga village, ∼35 km southwest of the capital city of Lilongwe on the central plains in Malawi, Africa, located at the crest of a local topographic-high characterized by crystalline basement. Study Focus: Groundwater aquifer systems in the shallow buried crystalline basement are geologically complex reservoir targets with historical...

Active fault data are commonly used in seismic hazard assessments, but there are challenges in deriving the slip rate, geometry, and frequency of earthquakes along active faults. Herein, we present the open-access geospatial Malawi Seismogenic Source Model (MSSM; 10.5281/zenodo.5599616), which describes the seismogenic properties of faults that for...

The onshore continental margins of western Central Africa have been hosting potentially damaging earthquake events for decades; yet, the links between the seismicity, the contemporary stress field, and pre-existing faults are not well understood. Here, we analyze the regional stress fields offshore and onshore along the coastal margin, and in the i...

The Northern Western Branch of the East African Rift System (EARS) serves as an ideal natural laboratory to investigate the influence of early-stage continental rifting on the reorganization of fluvial networks. The Albertine rift basin, NW branch of the EARS, exhibits a full graben geometry that is ~60 km wide, bounded by dominantly NE-striking la...

The major controls on the localization of deep crustal intraplate earthquakes remain enigmatic due to their deep hypocentral depths and rarity of coseismic surface ruptures. Here, we investigate the 3-D crustal density structure of the 2017 Mw 6.5 Botswana earthquake epicentral region, a widely felt lower-crustal (~24 - 29 km) event which is suspec...

We investigate the spatiotemporal patterns of strain accommodation during multiphase rift evolution in the Shire Rift Zone (SRZ), East Africa. The NW-trending SRZ records a transition from magma-rich rifting phases (Permian-Early Jurassic: Rift-Phase 1 (RP1), and Late Jurassic-Cretaceous: Rift-Phase 2 (RP2)) to a magma-poor phase in the Cenozoic (o...

We integrate new high-resolution aeromagnetic data with seismic reflection data, well logs, satellite remote sensing, and field observations to provide a regional view of buried and exposed structures in the Southern Oklahoma Aulacogen and to assess their potential for future seismicity. Trends ranging from NW−SE to ∼E−W, peaking at 330° ± 4.5° and...

Tectonic and paleo‐environmental reconstructions of rift evolution typically rely on the interpretation of sedimentary sequences, but this is rarely possible in early‐stage rifts where sediment volumes are low. To overcome this challenge, we use geomorphology to investigate landscape evolution and the role of different forcing mechanisms during bas...

We present the Malawi Active Fault Database (MAFD), an open‐access (https://doi.org/10.5281/zenodo.5507190) geospatial database of 113 fault traces in Malawi and neighboring Tanzania and Mozambique. Malawi is located within the East African Rift's (EAR) Western Branch where active fault identification is challenging because chronostratigraphic data...

One of the fundamental problems in continental rift segmentation and propagation is how strain is accommodated along large rift-bounding faults (border faults) since the segmentation of propagating border faults control the expression of rift zones, syn-rift depo-centers, and long-term basin evolution. In the Southern Malawi Rift, where previous st...

A rift is a nascent plate boundary where the continental lithosphere is extended and possibly broken. In this review, we focus on fundamental rift processes and how they evolve through time. We aim at providing a modular overview of the driving forces, resisting factors, and weakening processes as well as how their interaction generates the large v...

The paper is about earthquakes in Central Africa

We investigate the spatiotemporal patterns of strain accommodation during multiphase rift evolution in the Shire Rift Zone (SRZ), East Africa. The NW-trending SRZ records a transition from magma-rich rifting phases (Permian-Early Jurassic: Rift-Phase 1 (RP1), and Late Jurassic-Cretaceous: Rift-Phase 2 (RP2)) to a magma-poor phase in the Cenozoic (o...

Active fault data are commonly used in seismic hazard assessments, but there are challenges in deriving the slip rate, geometry, and frequency of earthquakes along active faults. Herein, we present the open-access geospatial Malawi Seismogenic Source Database (MSSD), which describes the seismogenic properties of faults that have formed during East...

On September 5–7, 2018, a series of tremors were reported in Nigeria’s capital city, Abuja. These events followed a growing list of tremors felt in the stable intraplate region, where earthquakes are not expected. Here, we review available seismological, geological, and geodetic data that may shed light on the origin of these tremors. First, we inv...

Little is known about rift kinematics and strain distribution during the earliest phase of extension due to the deep burial of the pre-rift and earliest rift structures beneath younger, rift-related deposits. Yet, this exact phase of basin development ultimately sets the stage for the location of continental plate divergence and breakup. Here, we i...

Although much is known about the interaction of faulting and sedimentation within the basins of active segmented continental rift systems, little is known about these processes within the interaction zones of varying geometries that separate the young interacting segments. We address this problem by exploring the non‐volcanic rift interaction zones...

Due to a decade of wastewater injection-triggered seismicity, the crystalline basement of northern Oklahoma has become the subject of intensive research, almost all of which has relied upon remote sensing or analog models and materials due to a near total absence of outcrops. This study reports relevant characteristics of material in drill cores fr...

On September 5-7, 2018, a series of tremors were reported in Nigeria's capital city, Abuja. These events followed a growing list of tremors felt in the stable intra-plate region, where earthquakes are not expected. Here, we review available seismological, geological, and geodetic data that may shed light on the origin of these tremors. First, we in...

We present the Malawi Active Fault Database (MAFD), a geospatial database of 114 active fault traces in Malawi, and in neighboring Tanzania and Mozambique. The MAFD has been developed from a multidisciplinary dataset: high resolution digital elevation models, field observations, aeromagnetic and gravity data, and seismic reflection surveys from off...

Little is known about rift kinematics and strain distribution during the earliest phase of extension due to the deep burial of the pre-rift and earliest rift structures beneath younger, rift-related deposits. Yet, this exact phase of basin development ultimately sets the stage for the location of continental plate divergence and breakup. Here, we i...

Abstract Oil and gas operations in sedimentary basins have revealed the occurrence of significant temperature anomalies at depth, raising the possibility of major geothermal resource potential in the sedimentary sequences. The efficient development of such a resource may require enhancement by hydraulic stimulation. However, effective stimulation r...

Although much is known about the interaction of faulting and sedimentation within the basins of active segmented continental rift systems, little is known about these processes within the interaction zones of varying geometries that separate the young interacting segments. We address this problem in the humid, magma-poor juvenile western branch of...

Substantial increase in the occurrence of injection-induced seismicity across Central and Eastern United States in the past decade, has highlighted a need for novel approaches to geophysical subsurface imaging of potentially seismogenic faults. Active clusters of seismicity illuminate linear fault segments within the sedimentary cover and crystalli...

Patterns of recent seismogenic fault reactivation in the granitic basement of north-central Oklahoma necessitates an understanding of the structural characteristics of the inherited basement-rooted faults. One area is the Nemaha Uplift and Fault Zone (NFZ) in north-central Oklahoma. We have analyzed the top-basement and intrabasement structures in...

Structures rooted in the crystalline basement frequently control the deformation of the host bedrock and the overlying sedimentary sequences. Here, we elucidate the structure of the c. 2‐km deep Precambrian granitic basement in the Anadarko Shelf, Oklahoma, and how the propagation of basement faults deformed the sedimentary cover. Although the basi...

There remains a limited understanding of the controls of pre‐existing structures on the architecture of deep‐water progradational sequences. In the Northern Taranaki Basin (NTB), New Zealand, Pliocene post‐extensional sedimentary sequences overlie Miocene back‐arc volcaniclastic units. We utilize seismic reflection datasets to investigate the relat...

Oil and gas operations in sedimentary basins have revealed significant temperatures at depth, raising the possibility of major geothermal resource potential in the sedimentary sequences. The efficient development of such a resource may require enhancement by hydraulic stimulation. However, effective stimulation relies on an initial assessment of in...

The 3 April 2017 Moiyabana intra-plate earthquake in central Botswana occurred in a region that, until then, had been assumed to be seismically quiet. Its location away from the East African Rift system in a Proterozoic mobile belt between Archean Cratons has raised questions on the triggering mechanism and sparked various studies investigating the...

Structures rooted in the crystalline basement frequently control the deformation of the host bedrock and the overlying sedimentary sequences. Here, we elucidate the structure of the ~ 2 km‐deep Precambrian granitic basement in the Anadarko Shelf, Oklahoma, and how the propagation of basement faults deformed the sedimentary cover. Although the basin...

Fault location and geometry are critical considerations in the reactivation of preexisting faults. Here, we combine relocated earthquake catalogs and focal mechanisms to delineate seismogenic faults in Oklahoma and southern Kansas and analyze their stress state. We first identify and map seismogenic faults based on earthquake clustering. We then ob...

Our understanding of how magma‐poor rifts accommodate strain remains limited largely due to sparse geophysical observations from these rift systems. To better understand the magma‐poor rifting processes, we investigate the lithospheric structure of the Malawi Rift, a segment of the magma‐poor western branch of the East African Rift System. We analy...

The Rukwa and North Malawi Rift Segments (RNMRS) both define a major rift‐oblique segment of the East African Rift System and are often regarded as discrete rifts due to the presence of the uplifted Mbozi block between them. Here we investigate the influence of basement fabrics on the coupling and linkage of border faults across an interrift transf...

https://explorer.aapg.org/story/articleid/52148/the-intra-basement-reflectors-in-the-stack-area-of-oklahoma

We explore the role of Coulomb stress transfer in the fault reactivation in Woodward, Oklahoma – a wastewater injection area. We address this issue by first defining fault segments from earthquake spatiotemporal clustering, then parameterizing the geometries of each segment by combining seismicity and focal mechanisms. Finally, we calculate Coulomb...

The Rukwa Rift and North Malawi Rift Segments (RNMRS) both define a major rift-oblique segment of the East African Rift System (EARS), and although the two young rifts show colinear approaching geometries, they are often regarded as discrete rifts due to the presence of the intervening Mbozi Block uplift located in-between. This problem has been co...

Our understanding of how magma poor rifts accommodate strain remains limited largely due to sparse geophysical data from these rift systems. In order to understand the rifting processes of magma poor rifts, we investigate the lithospheric structure of the Malawi Rift, which is part of the East African Rift System. We analyzed satellite gravity data...

Fault interpretation is an important step in seismic structural interpretation and has a bearing on the quantitative interpretation that may