subducting slabs - 2026 ACF Nationals

Packet 4: Tossup 14

Recycling of these objects is a proposed source of the HIMU (“high-mu”) source, which mixes with FOZO to contribute radiogenic lead to OIBs. These objects mix into a high-pressure melange that forms high strontium-87 melts due to contributions from AOC and sediment. These objects appear as high-V anomalies that stagnate at the transition zone before forming a “graveyard” in the D-double-prime layer, where (10[1])they may be one origin of (-5[1])LLSVPs. (-5[1])Arc (-5[1])volcanism is fueled (-5[1])by diapirs of melt (10[1])rising from these objects. (-5[2])The namesake “pull” of these objects exerts (10[1])force in the same direction as ridge push. (10[1])The typical 45-degree (10[2])dip of these (10[1])objects (10[1])produces the shape of Wadati–Benioff (10[1])zones (-5[2])as they descend into the mantle. (10[3])For 10 points, (10[1])name these objects pushed beneath continental plates at a namesake (-5[1])type of convergent boundary. ■END■ (10[7]0[5])

ANSWER: subducting slabs [or subducting plates or subduction plates; prompt on oceanic crust or oceanic plates or tectonic plates by asking “undergoing what process?”; prompt on subduction zones by asking “what part?”]

<Editors, Other Science> | M. Playoffs 4 (Editors 4)

= Average correct buzzpoint

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Buzzes

Player	Team	Opponent	Buzzpoint	Value
Owen Mimno	NYU A	Indiana	61	10
John Marvin	Chicago A	Toronto A	67	-5
Karthik Jayaram	UCLA	Toronto B	68	-5
Jason Lee	Rutgers	NYU B	69	-5
Matthew He	Texas	Cambridge	72	-5
Truman Hill	Vanderbilt	Georgia Tech C	76	10
Camden Walker	WashU	Minnesota	80	-5
Mason Yu	Brown	Waterloo	80	-5
Jason Qin	Columbia A	Maryland A	87	10
Shiva Tegulla	UCF	Cornell	95	10
Ved Muthusamy	Northwestern B	Illinois B	98	10
Tanay Bodducherla	UC Berkeley B	Northwestern A	98	10
Liam Rojas	Virginia	Ohio State	101	10
William Houston	Chicago B	Purdue	102	10
Brandon Weiss	Columbia B	Johns Hopkins	107	10
Jonathan Huang	MIT	Illinois A	108	-5
Rohan Ganeshan	Harvard	UC Berkeley A	108	-5
Arunn Sankar	Georgia Tech B	Georgia Tech A	114	10
Orion Keller	Virginia Tech	Stanford A	114	10
Yashwanth Bajji	Michigan	Stanford B	114	10
Jim Fan	North Carolina	Swarthmore	117	10
Matthew Wang	British Columbia	Pittsburgh	127	-5
Travis Johnson	Pittsburgh	British Columbia	132	0
Jack Lewis	Bruin	Penn State	132	10
Brendan Bethlehem	Cambridge	Texas	132	10
Benjamin Chapman	Toronto A	Chicago A	132	10
Andrew Wang	Illinois A	MIT	132	0
August Vanskike	Maryland B	Georgetown	132	0
Vayun Krishna	Georgetown	Maryland B	132	0
Jacob Hardin-Bernhardt	NYU B	Rutgers	132	10
Joey Sun	Toronto B	UCLA	132	10
Swapnil Garg	UC Berkeley A	Harvard	132	10
Puna Ekka	Minnesota	WashU	132	0
Michael Du	Waterloo	Brown	132	10

Summary

Tournament	Edition	Match	Heard	Conv. %	Neg %	Avg. Buzz
Main Site	2026-04-17	✓	24	83%	38%	110.40