Micro-XRF-inferred depositional history of the Orakei maar lake sediment sequence, Auckland, New Zealand

Abstract Lake sediment records offer insights into past climate and environmental changes. There are, however, few continuous lake from the Southern Hemisphere mid-latitudes that span last glacial interval (LGI) have requisite chronological control sampling resolution. Orakei maar paleolake in Auckland Volcanic Field, New Zealand, is an exception, as it contains a high-resolution record of lacustrine sedimentation its formative phreatomagmatic eruption ~ 130 ka, until post-glacial sea-level rise breached crater tuff rim connected to sea 9 ka. We used micro-XRF core scanning, dry bulk density, loss-on-ignition visual facies descriptions investigate depositional history response regional global drivers change, erosional events catchment. The was divided six phases: (I) Early warming with frequent in-wash events, followed by fluctuations coeval marine isotope stages (MIS) 5e mid-5c, (II) Warm, quiescent conditions during mid-MIS 5c 5a, (III) A colder, windier MIS 4, (IV) Warmer dominantly autochthonous 3, (V) Cold slow temperature increase onset late 2, (VI) Warm culminated formation peat unit at top sequence, which terminated influx massive muds basin 9.75 Comparison inferred evolution inferences benthic LGI shows general agreement, though changes consistently occur earlier than MIS. also agreement other records, but more detailed comparison requires additional proxy data such pollen, organic geochemistry biomarkers, better understand discrepancies between some records. This study demonstrated great potential for paleoclimate inference applicability scanning addressing questions about paleoenvironment. It highlighted intervals require further study.