The Seismic Club

Bidding System by John Jones, Rob Forster, and a few others.

What is the Seismic Club?

The Seismic Club is a relay-club bidding systems with very light openings. The 1 bid shows 16 or more points, and transfer-oriented responses begin a relay sequence . The goals are to rightside the contract, find the best strain, and find distribution slams or grand slams. Very light openings allow for greater preemption of the opponents, while the limited nature of the natural openings allows for adequate safety, as neither partner will expect too much.

The opening bids for Seismic Club are as follows (here is a chart of probabilities of these openings):

1: This shows any 16⁺-point hand. The 1 response is negative, showing 0-7 points. All other bids are transfer oriented and game forcing. The continuations after 1 are here. Since some obnoxious opponents like to disrupt our 1 methods, we have methods for dealing with interference.

1 (NV): When non-vulnerable, 1 shows 8-15 HCP and at least 2. This bid should be announced as "could be short." To show a 13-15 balanced hand NV, open 1 and then rebid 1NT (note that this 1NT is alertable).

1 (Vul): When vulnerable, 1 still shows 8-15 HCP, but now promises at least 4.

1/: Opening 1 of a major shows 8-15 HCP and at least 5 of the suit bid. The continuations over 1 of a major are here.

1NT (NV): A non-vulnerable (in 1^st- 3^rd seat) 1NT opening shows 10-12 HCP and a balanced hand. The responses to the weak 1NT are here.

1NT (Vul): When vulnerable, or in 4th seat, a 1NT opening shows 12⁺-15 ("good 12 to 15") HCP and a balanced hand. Over the "strong" 1NT, you can play whatever systems you normally play over a strong 1NT.

2: The 2 bid is natural, showing 10-15 points and either 6⁺ clubs or 5⁺ clubs and a 4-card major. A 6/5 two-suiter in /major is also possible. When alerted, this is easily summarized as "10-15 points and at least 5 clubs. If exactly 5 clubs, shows a 4-card major." Responses to 2 can be found here.

2: The 2 bid shows 10-15 points and a 3-suited hand short in . Possible shapes are 4414 ,(4/3)15, 4405. This can be summarized by: "10-15 points, at most 1, at most 5, no 5-card major.". Responses to 2 can be found here.

2/: These bids are preemptive and show 6⁺ cards in the suit bid and 3-8 points. You can use whatever response structure you want, I play that all non-raises are forcing and 2NT is Ogust. Since these hands could be very weak, it may be advisable to use an Ogust variation, such as an advance of 3 over the 3 response to ask "is your hand really that bad?"

2NT: This is a minor preempt showing 5-10 points and at least 5/5 in the minors. All responses through 4 are to play. A 4NT response is "vanilla" Blackwood, and 5NT asks opener to pick a minor slam.

3///: All of the 3-level bids are preemptive and natural. This should show a 7⁺-card suit and about 3-8 points.

3NT: This is a 4-level preempt in either minor with a broken suit. This can be passed, and 4 is pass-or-correct. With a hand that wants to play game if the minor is clubs responder bids 4, which is also pass-or-correct.

4/: The bids are Namyats, showing a strong major preempt. These bids show 8⁺-card suits in / (respectively) with at most 5 losers.

4/: These bids are weaker 8-card preempts and natural.