The Spongtang Massif is a remnant of Neotethyan ocean crust emplaced onto the Indian passive margin along the Indus-Yarlung-Tsangpo Suture in the NW Himalayan region of Ladakh. The age, tectonic evolution and timing of ophiolite obduction are critical to our understanding of the mechanisms via which entire oceans are formed, consumed and partly preserved before the onset of terminal continentcontinent collisions. Geochemistry of the gabbro and basaltic units suggest the presence of both MORBtype and primitive arc-related mafic rocks. Zircons extracted from the Spongtang Massif gabbros yield U-Pb (SHRIMP) ages of 136-133 Ma with initial εHfvalues of +14 to +16, indicating Early Cretaceous juvenile, depleted mantle sources devoid of contamination by older continental crust. Previously, Middle Jurassic (~177 Ma) zircon ages were obtained from gabbro and we suggest these represent MORB-type Neotethyan oceanic crust through which a younger intra-oceanic island-arc (Spong arc) developed in response to subduction initiation during the Early Cretaceous (~136 Ma). Our zircon ages are consistent with Early Cretaceous ages obtained for radiolarian cherts within the Spong Arc complex. Subduction beneath the Spong Arc continued until its collision with the northern Indian continental margin during the early Eocene. We suggest that the Spongtang Massif is equivalent to the nearby Dras island arc terrane. Intra-oceanic subduction beneath this system was possibly initiated along NNE-SSW trending transform faults in the Neotethyan Ocean, along which different ages of ocean crust was juxtaposed, thereby development of the Early Cretaceous Spong Arc is superimposed on the older Jurassic Spongtang N-MORB crust. The juvenile ɛHfsignature indicates the subduction system that spawned the Spong island arc was not related to the coeval Trans-Himalayan (Ladakh-Gangdese) arc that developed along the southern margin of Eurasia. The age, composition and nature of geological relationships with the underlying Indian rocks indicate the Spong Arc was a juvenile, intra-oceanic terrane that first collided with India before the onset of final continent-continent collision. Therefore, final late Eocene Neotethys closure was between the Kohistan-Ladakh (Eurasian) continental arc and the already inactive Indian + Spongtang margin.

The Dras Arc in NW India Himalaya is a belt of basaltic‐andesites intercalated with arkose‐dominated volcaniclastic rocks of the Nindam Formation situated along the Indus Suture between India and Eurasia. Debates exist as to whether these rocks developed in a forearc basin to the Eurasian margin or as part of an intraoceanic island arc system that collided with either India or Eurasia before final continental collision. Detrital zircons from the Nindam Formation yield U‐Pb age spectra with dominant youngest age populations of ~84–125 Ma, corresponding with arc magmatism. Sandstone provenance analysis from the Nindam Formation indicates that the Dras Arc evolved from an undissected arc to dissected arc over a period of ~41 Myr. Slightly older, smaller populations occur at ~135–185 Ma, corresponding with reported ages of Neotethyan ophiolites (e.g., Spongtang). The basal section of the Nindam Formation reveals the presence of arc‐derived basaltic‐andesite and tonalite clasts, plus ophiolitic components sourced from an adjacent accretionary complex. There is a distinct absence of quartz or felsic granitic clasts, suggesting that the Nindam Formation did not develop as a forearc basin to the Ladakh Batholith of southern Eurasia but rather as separate intraoceanic island arc. A distinct “Gondwanan” signature occurs in all samples, with zircon age peaks at ~514–988, ~1000–1588, ~1627–2444, and ~2500 Ma. We suggest that the Dras and Spong arcs are the same intraoceanic island arc system that developed as a result of subduction initiation along NNE‐SSW transform faults perpendicular to the Indian and Eurasia continents.

The Dras Arc is an island arc terrane located along the Indus Suture within the Ladakh Himalaya. To the north it is juxtaposed against the Eurasian Ladakh Batholith and to the south thrust over the Lamayuru Complex and Indian passive margin. Establishing the timing of inception and final collision of the Dras Arc is imperative to reconstructions of Neotethyan Ocean and timing of arc-continent collisions, prior to the terminal India-Asia continental collision. We describe and date felsic tuffs and adakitic felsic volcanic rock interbedded within the dominantly basaltic-andesitic Dras volcanic complex. These felsic volcanic units yield Upper Jurassic zircon U-Pb ages of 161 ± 1 and 152 ± 1 Ma respectively, making these the oldest reported units within the Dras Arc. We also report zircon U-Pb geochronologic and whole rock geochemical results for the Kargil Intrusive Suite which intrude the volcanic complex. Ages for the intrusives have been reproduced (102 ± 1 Ma and 101 ± 1 Ma), and a second, much younger phase (79 ± 1 Ma) has been identified as one of the youngest igneous phases within the Dras Arc. The presence of felsic, adakitic volcanism early in the evolution of the Dras Arc is consistent with the adolescent stages of island arc systems, in which dehydration melting of underplated arc or subducted oceanic crust generates small volumes of felsic magmas. Thus, the intraoceanic Dras Arc initiated in the Neotethyan Ocean during the Upper Jurassic, much earlier than previously reported, and possibly right up to collision during the late Paleocene between 60-50 Ma. It is likely that the Dras Arc developed together with the Spongtang Ophiolite-Spong Arc complex and the intraoceanic Zedong terrane of Tibet, first before colliding and accreting onto the passive margin of India prior to the terminal India-Asia continental collision.

Background: Intimate partner violence (IPV) is a major public health problem with harmful consequences. In Australia, there is no national standard screening tool and screening practice is variable across states. The objectives of this study were to assess in the antenatal healthcare setting: i) the validity of a new IPV brief screening tool and ii) women’s preference for screening response format, screening frequency and comfort level.Methods: 1,067 antenatal patients in a major metropolitan Victorian hospital in Australia completed a paper-based, self-administered survey. The survey included four screening items about whether they were Afraid/Controlled/Threatened/ Slapped or physically hurt (ACTS) by a partner or ex-partner in the last 12 months; and the Composite Abuse Scale (reference standard). The ACTS screen was presented firstly with a binary yes/no response format and then with a five-point ordinal frequency format from ‘never’ (0) to ‘very frequently’ (4). The main outcome measures were test statistics of the four-item ACTS screening tool (sensitivity, specificity, predictive values, and area under the curve) against the reference standard and women’s screening preferences.Results: Twelve-month IPV prevalence varied depending on the ACTS response format with 8% (83) positive on ACTS yes/no format, 12.8% (133) positive on ACTS ordinal frequency format and 10.5% (108) on the reference Composite Abuse Scale. Overall, the ACTS screening tool demonstrated clinical utility for the ordinal frequency format (AUC, 0.80; 95% CI = 0.76 to 0.85) and the binary yes/no format (AUC, 0.74, 95% CI = 0.69 to 0.79). The frequency scale (66%) had greater sensitivity than the yes/no scale (51%). The positive and negative predictive values were 56% and 96% for the frequency scale and 68% and 95% for the yes/no scale. Specificity was high regardless of screening question response options. Half (53%) of the women categorised as abused preferred the yes/no scale. Around half of the women (48%, 472) thought health care providers should ask pregnant women about IPV at every visit.Conclusions: The four-item ACTS tool (using the frequency scale and a cut-off of one on any item) is recommended for written self-administered screening of women to identify those experiencing IPV to enable first-line response and follow-up.

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