![]() First, the multi-branch feature extraction network of DenseNet121 is used to extract the respective features from the target scene and the contextual geological scene. ![]() Therefore, this study proposes a multimodal, deep-learning landform recognition framework based on a joint contextual geological and channel attention module (GCMENET). However, current genetic landform classification methods do not consider regional geological context, which can more accurately reflect the formation and evolution mechanism of geomorphic landforms than local ones. The observed spread in zircon (U-Th)/He dates likely reflects partial resetting associated with late mafic volcanism and/or hydrothermal activity within this dynamic rift environment.ĭeep learning networks have facilitated the automated scene recognition of landforms based on geomorphogenesis. Some (U-Th)/He dates are even younger than the depositional age of the sedimentary sample from which it was collected. A subset of zircons from both sites has concordant ²⁰⁶Pb/²³⁸U and (U-Th)/He dates, indicating a short duration between zircon crystallization and eruption of the host volcanic rock, but the majority of zircon (U-Th)/He dates are significantly younger than the ²⁰⁶Pb/²³⁸U dates for the same zircon. Despite being recorders of predominantly silicic activity, the detrital zircon U/Pb dates from both drill sites track the established timing of major volcanic phases in the EARS. ![]() The WTK sample yielded many zircons with Cenozoic ²⁰⁶Pb/²³⁸U dates similar to those from the NA core, but the WTK sample also sources a small population of Neoproterozoic zircons associated with rocks from the Mozambique Belt and reworked sedimentary deposits. ![]() NA zircon ²⁰⁶Pb/²³⁸U dates imply a sedimentary source from the western Afar margin, with a transition to more localized sediment reworking within the Afar Depression after a major regional tectonic reorganization and formation of a disconformity at ∼2.9 Ma. Most of these samples lack zircon ²⁰⁶Pb/²³⁸U dates from ∼22–13 Ma, due to a decrease in silicic volcanism and a watershed configuration limiting delivery of silicic source materials to the sample site. Analyses of four NA samples yielded zircon ²⁰⁶Pb/²³⁸U dates younger than ∼45 Ma, consistent with derivation from silicic volcanic rocks associated with EARS activity. We performed (U-Th)/He and U/Pb analyses on detrital zircons using single crystal laser ablation double dating (LADD) techniques. We sampled from drill cores collected by the Hominin Sites and Paleolakes Drilling Project (HSPDP) in Ethiopia and Kenya to study the detrital mineral records of the Northern Awash (NA 3.3–2.9 Ma) and West Turkana (WTK 1.9–1.4 Ma) drill cores. The identified Mesozoic sediment formation underlies a thick volcanic cover of 2.5 km which might be a suitable geologic setting for the growth of hydrocarbon reserves in the area and could probably be the source of CO2 degassing.ĭetrital zircons from two major rift basins within the East African Rift System (EARS) provide a means to evaluate not only sediment provenance and landscape dynamics in sedimentary basins, but also the timing of the silicic volcano-tectonic evolution of the rift system. In addition to the topography/thickness of each layers, this study for the first time identified a new Mesozoic horizon laying between a Tertiary ignimbrite layer and the crystalline basement at depths between -2499 m and -3060 m and having estimated maximum thickness of 561 m. The iteration process converges successively for each layer in each structural inversion and the result is validated against a priori information. Successive structural inversions are performed on three layers with their corresponding acceptable mean misfits’ errors. The model utilizes observed residual gravity anomaly and generates the structural relief maps of the respective layers with their corresponding gravity anomaly responses and the associated errors. These stacked grids represent major geological boundaries where density contrast exists. Stacked horizons with depth to tops of density contrast are obtained from well log data and previous geophysical studies. This study thus targets on mapping layers relief of shallow earth origin. The previous studies in the region focused on mapping crustal structures and Moho depths and least is known about the shallow earth. The inversion is carried out in wave number domain using Parker-Oldenburg algorithm and is constrained with initial model information. Multi layer 3D gravity inversion for layered structures and density interfaces are performed in the Central Main Ethiopian rift bounded between 38⁰00’-39⁰30’ E and 7⁰00’- 8⁰30’ N.
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