Anne-Morwenn Pastier

Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ | GFZ · Division of Earth Surface Process Modelling

Understanding past sea-level variations is essential to constrain future patterns of sea-level rise in response to warmer climate conditions. Due to good preservation and the possibility to use various geochemical methods to date fossil sea-level index points, the Last Interglacial (Marine Isotope Stage (MIS) 5e; 130-116 ka ago) is often regarded a...

The morphology of coastal sequences provides fundamental observations to unravel past sea level (SL) variations. For that purpose, converting morphometric observations into a SL datum requires understanding their morphogenesis. The long‐lasting sequence of coral reef terraces (CRTs) at Cape Laundi (Sumba Island, Indonesia) could serve as a benchmar...

The southeastern tip of Cuba Island is limited to the south by the N‐Caribbean boundary. By revisiting the impressive sequences of coastal terraces of this region, we decipher the Quaternary deformation pattern of this plate boundary. We present a detailed mapping of coastal terraces uplifted over a hundred kilometers of coastline, and U/Th dating....

Presented at the INQUA conference 2023 (Rome, Italy)

The morphology of coastal sequences provides fundamental observations to unravel past sea level (SL) variations. For that purpose, converting morphometric observations into a SL datum requires understanding their morphogenesis. The long-lasting sequence of coral reef terraces (CRTs) at Cape Laundi (Sumba Island, Indonesia) could serve as a benchmar...

We present an analysis of ground deformation induced by large-scale seasonal rainfall in Southern Africa, based on GPS and GRACE time series and on simulations of elastic flexural response to hydrological loading. This large-scale study including South Zambia, South Angola, North Namibia and North Botswana displays a latitudinal precipitation gradi...

The history of sea level across the Quaternary is essential for assessing past and future climate. Global sea-level reconstructions are typically derived from oxygen isotope curves, but require calibration with geological constraints that are scarce prior to the last glacial cycle (>130 thousand years ago). Here we show that the coral reef terrace...

The morphology of fossil coral reef (FCR) sequences provides fundamental observations to unravel past sea levels (SL), including the possible intra-Last Interglacial (LIG) SL oscillations, and thus to anticipate future variations. For that purpose, converting morphometric observations into SL datum requires understanding the FCRs morphogenesis. The...

The morphology of coral reef sequences (CRTs) provides fundamental observations to unravel past sea levels, including the possible intra-Last Interglacial (LIG) sea level oscillations. For that purpose, converting morphometric observations into sea level datum requires understanding the CRTs morphogenesis. The canonical sequence of CRTs at Cape Lau...

The history of sea level across the Quaternary is essential for assessing past and future climate and geodynamics. Global sea-level reconstructions are typically derived from oxygen isotope curves, but require calibration with geological constraints that are particularly scarce prior to the last glacial cycle (>130 ka). The exceptionally well-prese...

The emerged coral reef terrace sequence at Cape Laundi, on the north coast of Sumba Island (Indonesia), with at least 18 successive strandlines, remains poorly dated in spite of numerous previous data. The age discrepancies within these coral reef terraces (CRTs) were previously explained by their polycyclic nature, triggered by marine erosion and...

Sequences of coral reef terraces result from the interplay between biogenic and clastic sedimentary production, relative sea level (RSL) variations, wave erosion and tectonic forcing. Reefal sequences are gold standard proxies for paleo-sea level and tectonic reconstructions, but their contribution is usually restricted to a bijective approach, cor...

The variety of coral reefs morphologies highlights their sensitivities to several forcings; fossil reefs stack in sequences that are accordingly diverse. In order to understand their genesis and architectures, we devised a numerical approach, accounting for Quaternary sea level oscillations, vertical land motion, initial slope, wave erosion, and re...

Sundaland is the currently partially drowned continental landmass that encompasses Borneo, Sumatra, Java, and the Malay Peninsula. It has episodically been reclaimed by the sea during successive Quaternary glaciations, and is commonly thought to be vertically stable. Combining geomorphological observations with numerical simulations of coral reef g...

Many islands of the eastern Indonesian Archipelago exhibit Late Cenozoic sequences of coral reef terraces. In SE Sulawesi, on the Tukang Besi and Buton archipelagos, we identified 23 islands bearing such sequences. Remote sensing imagery and field mapping combined to U/Th and 14C dating enable to establish a chronologic framework of the reef terrac...

Global variations in reef productivity during the Quaternary depend on external parameters that may alter the global chemical balance in the oceans and atmosphere. We designed a numerical model that simulates reef growth, erosion and sedimentation on coastlines undergoing sea‐level oscillations, and uplift or subsidence. We further develop a probab...

The Okavango Delta is an endorheic system forming an alluvial fan in the Kalahari depression. The local ecosystem is paced by the annual flood coming from the Angolan highlands, blocked downstream by the normal faults scarps of the Okavango graben. This annual regime is highly variable, with the spatial distribution of the flood differing every yea...